query: will SARS-CoV2 infected people develop immunity? Is cross protection possible?

positive: Prevention and treatment of COVID-19 disease by controlled modulation of innate immunity The recent outbreak of coronavirus disease 2019 (COVID-19), triggered by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) poses an enormous threat to global public health and economies. Human coronaviruses normally cause no or mild respiratory disease but in the past two decades, potentially fatal coronavirus infections have emerged, causing respiratory tract illnesses such as pneumonia and bronchitis. These include severe acute respiratory syndrome coronavirus (SARS-CoV), followed by the Middle East respiratory syndrome coronavirus (MERS-CoV), and recently the SARS-CoV-2 coronavirus outbreak that emerged in Wuhan, China, in December 2019. Currently, most COVID-19 patients receive traditional supportive care including breathing assistance. To halt the ongoing spread of the pandemic SARS-CoV-2 coronavirus and rescue individual patients, established drugs and new therapies are under evaluation. Since it will be some time until a safe and effective vaccine will be available, the immediate priority is to harness innate immunity to accelerate early antiviral immune responses. Second, since excessive inflammation is a major cause of pathology, targeted anti-inflammatory responses are being evaluated to reduce inflammation-induced damage to the respiratory tract and cytokine storms. Here, we highlight prominent immunotherapies at various stages of development that aim for augmented anti-coronavirus immunity and reduction of pathological inflammation.

positive: Serodiagnostics for Severe Acute Respiratory Syndrome-Related Coronavirus-2: A Narrative Review Accurate serologic tests to detect host antibodies to severe acute respiratory syndrome-related coronavirus-2 (SARS-CoV-2) will be critical for the public health response to the coronavirus disease 2019 pandemic. Many use cases are envisaged, including complementing molecular methods for diagnosis of active disease and estimating immunity for individuals. At the population level, carefully designed seroepidemiologic studies will aid in the characterization of transmission dynamics and refinement of disease burden estimates and will provide insight into the kinetics of humoral immunity. Yet, despite an explosion in the number and availability of serologic assays to test for antibodies against SARS-CoV-2, most have undergone minimal external validation to date. This hinders assay selection and implementation, as well as interpretation of study results. In addition, critical knowledge gaps remain regarding serologic correlates of protection from infection or disease, and the degree to which these assays cross-react with antibodies against related coronaviruses. This article discusses key use cases for SARS-CoV-2 antibody detection tests and their application to serologic studies, reviews currently available assays, highlights key areas of ongoing research, and proposes potential strategies for test implementation.

positive: Cross-immunity between respiratory coronaviruses may limit COVID-19 fatalities Of the seven coronaviruses associated with disease in humans, SARS-CoV, MERS-CoV and SARS-CoV-2 cause considerable mortality but also share significant sequence homology, and potentially antigenic epitopes capable of inducing an immune response. The degree of similarity is such that perhaps prior exposure to one virus could confer partial immunity to another. Indeed, data suggests a considerable amount of cross-reactivity and recognition by the hosts immune response between different coronavirus infections. While the ongoing COVID-19 outbreak rapidly overwhelmed medical facilities of particularly Europe and North America, accounting for 78% of global deaths, only 8% of deaths have occurred in Asia where the outbreak originated. Interestingly, Asia and the Middle East have previously experienced multiple rounds of coronavirus infections, perhaps suggesting buildup of acquired immunity to the causative SARS-CoV-2 that underlies COVID-19. This article hypothesizes that a causative factor underlying such low morbidity in these regions is perhaps (at least in part) due to acquired immunity from multiple rounds of coronavirus infections and discusses the mechanisms and recent evidence to support such assertions. Further investigations of such phenomenon would allow us to examine strategies to confer protective immunity, perhaps aiding vaccine development.

positive: Coronavirus and PARP expression dysregulate the NAD Metabolome: a potentially actionable component of innate immunity SARS-CoV-2 is a coronavirus (CoV) and cause of COVID-19, which is much more lethal in older people and those with comorbid conditions for unknown reasons. Innate immune responses to CoVs are initiated by recognition of double-stranded RNA and induction of interferon, which turns on a gene expression program that inhibits viral replication. Here we show that SARS-CoV-2 infection of cells, ferrets and a person strikingly dysregulates the NAD gene set by inducing a set of PARP family members that includes enzymes required for the innate immune response to CoVs. CoV infection also induces a severe attack on host cell NAD. Overexpression of one induced enzyme, PARP10, is sufficient to depress host NAD. Gene expression and pharmacological data suggest that boosting NAD through the nicotinamide and nicotinamide riboside kinase pathways may restore antiviral PARP functions to support innate immunity to CoVs, whereas PARP1,2 inhibition does not restore PARP10 activity.

positive: Design of a Novel Multi Epitope-Based Vaccine for Pandemic Coronavirus Disease (COVID-19) by Vaccinomics and Probable Prevention Strategy against Avenging Zoonotics The emergence and rapid expansion of the coronavirus disease (COVID-19) require the development of effective countermeasures especially a vaccine to provide active acquired immunity against the virus. This study presented a comprehensive vaccinomics approach applied to the complete protein data published so far in the National Center for Biotechnological Information (NCBI) coronavirus data hub. We identified non-structural protein 8 (Nsp8), 3C-like proteinase, and spike glycoprotein as potential targets for immune responses to COVID-19. Epitopes prediction illustrated both B-cell and T-cell epitopes associated with the mentioned proteins. The shared B and T-cell epitopes: DRDAAMQRK and QARSEDKRA of Nsp8, EDMLNPNYEDL and EFTPFDVVR of 3C-like proteinase, and VNNSYECDIPI of the spike glycoprotein are regions of high potential interest and have a high likelihood of being recognized by the human immune system. The vaccine construct of the epitopes shows stimulation of robust primary immune responses and high level of interferon gamma. Also, the construct has the best conformation with respect to the tested innate immune receptors involving vigorous molecular mechanics and solvation energy. Designing of vaccination strategies that target immune response focusing on these conserved epitopes could generate immunity that not only provide cross protection across Betacoronaviruses but additionally resistant to virus evolution.

positive: Different pattern of pre-existing SARS-COV-2 specific T cell immunity in SARS-recovered and uninfected individuals Memory T cells induced by previous infections can influence the course of new viral infections. Little is known about the pattern of SARS-CoV-2 specific pre-existing memory T cells in human. Here, we first studied T cell responses to structural (nucleocapsid protein, NP) and non-structural (NSP-7 and NSP13 of ORF1) regions of SARS-CoV-2 in convalescent from COVID-19 (n=24). In all of them we demonstrated the presence of CD4 and CD8 T cells recognizing multiple regions of the NP protein. We then show that SARS-recovered patients (n=23), 17 years after the 2003 outbreak, still possess long-lasting memory T cells reactive to SARS-NP, which displayed robust cross-reactivity to SARS-CoV-2 NP. Surprisingly, we observed a differential pattern of SARS-CoV-2 specific T cell immunodominance in individuals with no history of SARS, COVID-19 or contact with SARS/COVID-19 patients (n=18). Half of them (9/18) possess T cells targeting the ORF-1 coded proteins NSP7 and 13, which were rarely detected in COVID-19- and SARS-recovered patients. Epitope characterization of NSP7-specific T cells showed recognition of protein fragments with low homology to “common cold” human coronaviruses but conserved among animal betacoranaviruses. Thus, infection with betacoronaviruses induces strong and long-lasting T cell immunity to the structural protein NP. Understanding how pre-existing ORF-1-specific T cells present in the general population impact susceptibility and pathogenesis of SARS-CoV-2 infection is of paramount importance for the management of the current COVID-19 pandemic.

positive: Prevalence of IgG antibodies to SARS-CoV-2 in Wuhan -implications for the ability to produce long-lasting protective antibodies against SARS-CoV-2 Background It is to be determined whether people infected with SARS-CoV-2 will develop long-term immunity against SARS-CoV-2 and retain long-lasting protective antibodies after the infection is resolved. This study was to explore to explore the outcomes of IgG antibodies to SARS-CoV-2 in four groups of individuals in Wuhan, China. Methods We included the following four groups of individuals who received both COVID-19 IgM/IgG tests and RT-PCR tests for SARS-CoV-2 from February 29, 2020 to April 29, 2020: 1470 hospitalized patients with COVID-19 from Leishenshan Hospital, Zhongnan Hospital of Wuhan University, and Wuhan No. 7 Hospital, 3832 healthcare providers without COVID-19 diagnosis, 19555 general workers, and 1616 other patients to be admitted to the hospital (N=26473). COVID-19 patients who received IgM/IgG tests <21 days after symptom onset were excluded. Results IgG prevalence was 89.8% (95% CI 88.2-91.3%) in COVID-19 patients, 4.0% (95% CI 3.4-4.7%) in healthcare providers, 4.6 (95% CI 4.3-4.9 %) in general workers, and 1.0% in other patients (p all <0.001 for comparisons with COVID-19 patients). IgG prevalence increased significantly by age among healthcare workers and general workers. Prevalence of IgM antibodies to SARS-CoV-2 was 31.4% in COVID-19 patients, 1.5% in healthcare providers, 1.3% in general workers, and 0.2% in other patients. Conclusions Very few healthcare providers had IgG antibodies to SARS-CoV-2, though a significant proportion of them had been infected with the virus. After SARS-CoV-2 infection, people are unlikely to produce long-lasting protective antibodies against this virus.

positive: Complete protection against severe acute respiratory syndrome coronavirus-mediated lethal respiratory disease in aged mice by immunization with a mouse-adapted virus lacking E protein. Zoonotic coronaviruses, including the one that caused severe acute respiratory syndrome (SARS), cause significant morbidity and mortality in humans. No specific therapy for any human coronavirus is available, making vaccine development critical for protection against these viruses. We previously showed that recombinant SARS coronavirus (SARS-CoV) (Urbani strain based) lacking envelope (E) protein expression (rU-ΔE) provided good but not perfect protection in young mice against challenge with virulent mouse-adapted SARS-CoV (MA15). To improve vaccine efficacy, we developed a second set of E-deleted vaccine candidates on an MA15 background (rMA15-ΔE). rMA15-ΔE is safe, causing no disease in 6-week-, 12-month-, or 18-month-old BALB/c mice. Immunization with this virus completely protected mice of three ages from lethal disease and effected more-rapid virus clearance. Compared to rU-ΔE, rMA15-ΔE immunization resulted in significantly greater neutralizing antibody and SARS-CoV-specific CD4 and CD8 T cell responses. After challenge, inflammatory cell infiltration, edema, and lung destruction were decreased in the lungs of rMA15-ΔE-immunized mice compared to those in rU-ΔE-immunized 12-month-old mice. Collectively, these results show that immunization with a species-adapted attenuated coronavirus lacking E protein expression is safe and provides optimal immunogenicity and long-term protection against challenge with lethal virus. This approach will be generally useful for development of vaccines protective against human coronaviruses as well as against coronaviruses that cause disease in domestic and companion animals.

positive: Immunoinformatic analysis of the SARS-CoV-2 Envelope protein as a strategy to assess cross-protection against COVID-19 Envelope protein of coronaviruses is a structural protein existing in both monomeric and homo-pentameric form. It has been related to a multitude of roles including virus infection, replication, dissemination and immune response stimulation. In the present study, we employed an immunoinformatic approach to investigate the major immunogenic domains of the SARS-CoV-2 envelope protein and map them among the homologue proteins of coronaviruses with tropism for animal species that are closely inter-related with the human beings population all over the world. Also, when not available, we predicted the envelope protein structural folding and mapped SARS-CoV-2 epitopes. Envelope sequences alignment provides evidence of high sequence homology for some of the investigated virus specimens; while the structural mapping of epitopes resulted in the interesting maintenance of the structural folding and epitope sequence localization also in the envelope proteins scoring a lower alignment score. In line with the One-Health approach, our evidences provide a molecular structural rationale for a potential role of taxonomically related coronaviruses in conferring protection from SARS-CoV-2 infection and identifying potential candidates for the development of diagnostic tools and prophylactic-oriented strategies.

positive: Particulate multivalent presentation of the receptor binding domain induces protective immune responses against MERS-CoV Middle East respiratory syndrome coronavirus (MERS-CoV) is a WHO priority pathogen for which vaccines are urgently needed. Using an immune-focusing approach, we created self-assembling particles multivalently displaying critical regions of the MERS-CoV spike protein âfusion peptide, heptad repeat 2, and receptor binding domain (RBD) â and tested their immunogenicity and protective capacity in rabbits. Using a "plug-and-display" SpyTag/SpyCatcher system, we coupled RBD to lumazine synthase (LS) particles producing multimeric RBD-presenting particles (RBD-LS). RBD-LS vaccination induced antibody responses of high magnitude and quality (avidity, MERS-CoV neutralizing capacity, and mucosal immunity) with cross-clade neutralization. The antibody responses were associated with blocking viral replication and upper and lower respiratory tract protection against MERS-CoV infection in rabbits. This arrayed multivalent presentation of the viral RBD using the antigen-SpyTag/LS-SpyCatcher is a promising MERS-CoV vaccine candidate and this platform may be applied for the rapid development of vaccines against other emerging viruses such as SARS-CoV-2.

positive: Longitudinal Change of Severe Acute Respiratory Syndrome Coronavirus 2 Antibodies in Patients with Coronavirus Disease 2019 BACKGROUND: A novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has recently emerged and caused the rapid spread of coronavirus disease 2019 (COVID-19) worldwide. METHODS: We did a retrospective study and included COVID-19 patients admitted to Renmin Hospital of Wuhan University between 1 February and 29 February 2020. Antibody assay was conducted to detect COVID-19 envelope protein E and nucleocapsid protein N antigen. RESULTS: One hundred twelve patients were recruited with symptoms of fever, cough, fatigue, myalgia, and diarrhea. All patients underwent antibody tests. Fifty-eight (51.79%) were positive for both immunoglobulin M (IgM) and immunoglobulin G (IgG), 7 (6.25%) were negative for both antibodies, 1 (0.89%) was positive for only IgM, and 46 (41.07%) were positive for only IgG. IgM antibody appeared within a week post-disease onset, lasted for 1 month, and gradually decreased, whereas IgG antibody was produced 10 days after infection and lasted for a longer time. However, no significant difference in levels of IgM and IgG antibodies between positive and negative patients of nucleic acid test after treatment was found. CONCLUSIONS: Our results indicate that serological tests could be a powerful approach for the early diagnosis of COVID-19.

positive: A Guide to COVID‐19: a global pandemic caused by the novel coronavirus SARS‐CoV‐2 The emergence of the SARS‐CoV‐2 strain of the human coronavirus has thrown the world into the midst of a new pandemic. In the human body, the virus causes COVID‐19, a disease characterized by shortness of breath, fever, and pneumonia, which can be fatal in vulnerable individuals. SARS‐CoV‐2 has characteristics of past human coronaviruses, with close genomic similarities to SARS‐CoV, the virus that causes the disease SARS. Like these related coronaviruses, SARS‐CoV‐2 is transmitted through the inhalation of droplets and interaction with contaminated surfaces. Across the world, laboratories are developing candidate vaccines for the virus – with vaccine trials underway in the US and the United Kingdom ‐ and considering various drugs for possible treatments and prophylaxis. Here, we provide an overview of SARS‐CoV‐2 by analyzing its virology, epidemiology, and modes of transmission while examining the current progress of testing procedures and possible treatments through drugs and vaccines.

positive: Serological differentiation between COVID-19 and SARS infections. In response to the coronavirus disease 2019 (COVID-19) outbreak, caused by the SARS-CoV-2 virus, multiple diagnostic tests are required globally for acute disease diagnosis, contact tracing, monitoring of asymptomatic infection rates and assessing herd immunity. While PCR remains the frontline test of choice in the acute diagnostic setting, serological tests are urgently needed to fulfil the other requirements. Unlike PCR tests which are highly specific for each virus, cross-reactivity could potentially be a major challenge for COVID-19 antibody tests considering there are six other coronaviruses known to infect humans. Among the human pathogens, SARS-CoV is genetically most related to SARS-CoV-2 sharing approximately 80% sequence identity and both belong to the species SARS related coronavirus (SARSr-CoV) in the genus Betacoronavirus of family Coronaviridae. In this study, we developed and compared the performance of four different serological tests to comprehensively assess the cross-reactivity between COVID-19 and SARS patient sera. Our results indicate that there is a significant cross-reactivity when N protein of either SARS-CoV or SARS-CoV-2 is used. The S1 or RBD derived the spike (S) protein offers better specificity. Amongst the different platforms, capture ELISA performed best. Finally, we found that SARS survivors all have significant level of antibodies remaining in their blood 17 years after infection. We discovered that anti-N antibodies waned more than anti-RBD antibodies, and the latter is known to play a more important role in providing protective immunity.

positive: Structural features of coronavirus SARS-CoV-2 spike protein: Targets for vaccination Various human pathogenic viruses employ envelope glycoproteins for host cell receptor recognition and binding, membrane fusion and viral entry. The spike (S) glycoprotein of betacoronavirus SARS-CoV-2 is a homotrimeric class I fusion protein that exists in a metastable conformation for cleavage by host cell proteases furin and TMPRSS2, thereby undergoing substantial structural rearrangement for ACE2 host cell receptor binding and subsequent viral entry by membrane fusion. The S protein is densely decorated with N-linked glycans protruding from the trimer surface that affect S protein folding, processing by host cell proteases and the elicitation of humoral immune response. Deep insight into the sophisticated structure of SARS-CoV-2 S protein may provide a blueprint for vaccination strategies, as reviewed herein.

positive: Perspectives of Immune Therapy in Coronavirus Disease 2019 The global fight against coronavirus disease 2019 (COVID-19) is largely based on strategies to boost immune responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and prevent its severe course and complications. The human defence may include antibodies which interact with SARS-CoV-2 and neutralize its aggressive actions on multiple organ systems. Protective cross-reactivity of antibodies against measles and other known viral infections has been postulated, primarily as a result of the initial observations of asymptomatic and mild COVID-19 in children. Uncontrolled case series have demonstrated virus-neutralizing effect of convalescent plasma, supporting its efficiency at early stages of contracting SARS-CoV-2. Given the variability of the virus structure, the utility of convalescent plasma is limited to the geographic area of its preparation, and for a short period of time. Intravenous immunoglobulin may also be protective in view of its nonspecific antiviral and immunomodulatory effects. Finally, human monoclonal antibodies may interact with some SARS-CoV-2 proteins, inhibiting the virus-receptor interaction and prevent tissue injury. The improved understanding of the host antiviral responses may help develop safe and effective immunotherapeutic strategies against COVID-19 in the foreseeable future.

positive: Genetic diversity and evolution of SARS-CoV-2 Abstract COVID-19 is a viral respiratory illness caused by a new coronavirus called SARS-CoV-2. The World Health Organization declared the SARS-CoV-2 outbreak a global public health emergency. We performed genetic analyses of eighty-six complete or near-complete genomes of SARS-CoV-2 and revealed many mutations and deletions on coding and non-coding regions. These observations provided evidence of the genetic diversity and rapid evolution of this novel coronavirus.

positive: Towards effective COVID-19 vaccines: Updates, perspectives and challenges (Review) In the current context of the pandemic triggered by SARS-COV-2, the immunization of the population through vaccination is recognized as a public health priority. In the case of SARS-COV-2, the genetic sequencing was done quickly, in one month. Since then, worldwide research has focused on obtaining a vaccine. This has a major economic impact because new technological platforms and advanced genetic engineering procedures are required to obtain a COVID-19 vaccine. The most difficult scientific challenge for this future vaccine obtained in the laboratory is the proof of clinical safety and efficacy. The biggest challenge of manufacturing is the construction and validation of production platforms capable of making the vaccine on a large scale.

positive: Diagnostic techniques for COVID-19 and new developments COVID-19 pandemic is a serious global health issue today due to the rapid human to human transmission of SARS-CoV-2, a new type of coronavirus that causes fatal pneumonia. SARS -CoV-2 has a faster rate of transmission than other coronaviruses such as SARS and MERS and until now there are no approved specific drugs or vaccines for treatment. Thus, early diagnosis is crucial to prevent the extensive spread of the disease. The reverse transcription-polymerase chain reaction (RT-PCR) is the most routinely used method until now to detect SARS-CoV-2 infections. However, several other faster and accurate assays are being developed for the diagnosis of COVID-19 aiming to control the spread of infection through the identification of patients and immediate isolation. In this review, we will discuss the various detection methods of the SARS-CoV-2 virus including the recent developments in immunological assays, amplification techniques as well as biosensors.

positive: A double epidemic model for the SARS propagation BACKGROUND: An epidemic of a Severe Acute Respiratory Syndrome (SARS) caused by a new coronavirus has spread from the Guangdong province to the rest of China and to the world, with a puzzling contagion behavior. It is important both for predicting the future of the present outbreak and for implementing effective prophylactic measures, to identify the causes of this behavior. RESULTS: In this report, we show first that the standard Susceptible-Infected-Removed (SIR) model cannot account for the patterns observed in various regions where the disease spread. We develop a model involving two superimposed epidemics to study the recent spread of the SARS in Hong Kong and in the region. We explore the situation where these epidemics may be caused either by a virus and one or several mutants that changed its tropism, or by two unrelated viruses. This has important consequences for the future: the innocuous epidemic might still be there and generate, from time to time, variants that would have properties similar to those of SARS. CONCLUSION: We find that, in order to reconcile the existing data and the spread of the disease, it is convenient to suggest that a first milder outbreak protected against the SARS. Regions that had not seen the first epidemic, or that were affected simultaneously with the SARS suffered much more, with a very high percentage of persons affected. We also find regions where the data appear to be inconsistent, suggesting that they are incomplete or do not reflect an appropriate identification of SARS patients. Finally, we could, within the framework of the model, fix limits to the future development of the epidemic, allowing us to identify landmarks that may be useful to set up a monitoring system to follow the evolution of the epidemic. The model also suggests that there might exist a SARS precursor in a large reservoir, prompting for implementation of precautionary measures when the weather cools down.

positive: Detection of SARS-CoV-2-specific humoral and cellular immunity in COVID-19 convalescent individuals Summary The World Health Organization has declared SARS-CoV-2 virus outbreak a world-wide pandemic. However, there is very limited understanding on the immune responses, especially adaptive immune responses to SARS-CoV-2 infection. Here, we collected blood from COVID-19 patients who have recently become virus-free and therefore were discharged, and detected SARS-CoV-2-specific humoral and cellular immunity in 8 newly discharged patients. Follow-up analysis on another cohort of 6 patients 2 weeks post discharge also revealed high titers of IgG antibodies. In all 14 patients tested, 13 displayed serum neutralizing activities in a pseudotype entry assay. Notably, there was a strong correlation between neutralization antibody titers and the numbers of virus-specific T cells. Our work provides a basis for further analysis of protective immunity to SARS-CoV-2, and understanding the pathogenesis of COVID-19, especially in the severe cases. It has also implications in developing an effective vaccine to SARS-CoV-2 infection.

positive: Serological differentiation between COVID-19 and SARS infections In response to the coronavirus disease 2019 (COVID-19) outbreak, caused by the SARS-CoV-2 virus, multiple diagnostic tests are required globally for acute disease diagnosis, contact tracing, monitoring of asymptomatic infection rates and assessing herd immunity. While PCR remains the frontline test of choice in the acute diagnostic setting, serological tests are urgently needed to fulfil the other requirements. Unlike PCR tests which are highly specific for each virus, cross-reactivity could potentially be a major challenge for COVID-19 antibody tests considering there are six other coronaviruses known to infect humans. Among the human pathogens, SARS-CoV is genetically most related to SARS-CoV-2 sharing approximately 80% sequence identity and both belong to the species SARS related coronavirus (SARSr-CoV) in the genus Betacoronavirus of family Coronaviridae. In this study, we developed and compared the performance of four different serological tests to comprehensively assess the cross-reactivity between COVID-19 and SARS patient sera. Our results indicate that there is a significant cross-reactivity when N protein of either SARS-CoV or SARS-CoV-2 is used. The S1 or RBD derived the spike (S) protein offers better specificity. Amongst the different platforms, capture ELISA performed best. Finally, we found that SARS survivors all have significant level of antibodies remaining in their blood 17 years after infection. We discovered that anti-N antibodies waned more than anti-RBD antibodies, and the latter is known to play a more important role in providing protective immunity.

positive: Epitope-based chimeric peptide vaccine design against S, M and E proteins of SARS-CoV-2 etiologic agent of global pandemic COVID-19: an in silico approach Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause of the ongoing pandemic of coronavirus disease 2019 (COVID-19), a public health emergency of international concern declared by the World Health Organization (WHO). An immuno-informatics approach along with comparative genomic was applied to design a multi-epitope-based peptide vaccine against SARS-CoV-2 combining the antigenic epitopes of the S, M and E proteins. The tertiary structure was predicted, refined and validated using advanced bioinformatics tools. The candidate vaccine showed an average of ≥ 90.0% world population coverage for different ethnic groups. Molecular docking of the chimeric vaccine peptide with the immune receptors (TLR3 and TLR4) predicted efficient binding. Immune simulation predicted significant primary immune response with increased IgM and secondary immune response with high levels of both IgG1 and IgG2. It also increased the proliferation of T-helper cells and cytotoxic T-cells along with the increased INF-γ and IL-2 cytokines. The codon optimization and mRNA secondary structure prediction revealed the chimera is suitable for high-level expression and cloning. Overall, the constructed recombinant chimeric vaccine candidate demonstrated significant potential and can be considered for clinical validation to fight against this global threat, COVID-19.

positive: Estimating excess 1- year mortality from COVID-19 according to underlying conditions and age in England: a rapid analysis using NHS health records in 3.8 million adults RAPID COMMUNICATION 22 March 2020 Estimating excess 1- year mortality from COVID-19 according to underlying conditions and age in England: a rapid analysis using NHS health records in 3.8 million adults Background: The medical, health service, societal and economic impact of the COVID-19 emergency has unknown effects on overall population mortality. Previous models of population mortality are based on death over days among infected people, nearly all of whom (to date at least) have underlying conditions. Models have not incorporated information on high risk conditions or their longer term background (pre-COVID-19) mortality. We estimated the excess number of deaths over 1 year under different COVID-19 incidence rates and differing mortality impacts. Methods: Using population based linked primary and secondary care electronic health records in England (HDR UK - CALIBER), we report the prevalence of underlying conditions defined by UK Public Health England COVID-19 guidelines (16 March 2020) in 3,862,012 individuals aged ≥30 years from 1997-2017. We used previously validated phenotypes, openly available (https://caliberresearch.org/portal), for each condition using ICD-10 diagnosis, Read, procedure and medication codes. We estimated the 1-year mortality in each condition, and developed simple models of excess COVID-19-related deaths assuming relative risk (RR) of the impact of the emergency (compared to background mortality) of 1.2, 1.5 and 2.0. Findings: 20.0% of the population are at risk according to current PHE guidelines, of which; 13.7% were age>70 years and 6.3% aged ≤70 years with ≥1 underlying condition (cardiovascular disease (2.3%), diabetes (2.2%), steroid therapy (1.9%), severe obesity (0.9%), chronic kidney disease (0.6%) and chronic obstructive pulmonary disease, COPD (0.5%). Multimorbidity (co-occurrence of ≥2 conditions in an individual) was common (10.1%). The 1-year mortality in the at-risk population was 4.46%, and age and underlying conditions combine to influence background risk, varying markedly across conditions (5.9% in age>70 years, 8.6% for COPD and 13.1% in those with ≥3 or more conditions). In a suppression scenario (at SARS CoV2 rates of 0.001% of the UK population), there would be minimal excess deaths (3 and 7 excess deaths at relative risk, RR, 1.5 and 2.0 respectively). At SARS CoV2 rates of 10% of the UK population (mitigation) the model estimates the numbers of excess deaths as: 13791, 34479 and 68957 (at RR 1.2, 1.5 and 2.0 respectively). At SARS CoV2 rates of 80% in the UK population (do-nothing), the model estimates the number of excess deaths as 110332, 275,830 and 551,659 (at RR 1.2, 1.5 and 2.0) respectively. Interpretation: We provide the public, researchers and policy makers a simple model to estimate the excess mortality over 1 year from COVID-19, based on underlying conditions at different ages. If the relative mortality impact of COVID-19 were to be about 20% (similar magnitude as the established winter vs summer mortality excess), then the excess deaths would be 0 when 1 in 100 000 (suppression), 13791 when 1 in 10 (mitigation) and 110332 when 8 in 10 are infected (do nothing) scenario. However, the relative impact of COVID-19 is unknown. If the emergency were to double the mortality risk, then we estimate 7, 68957 and 551,659 excess deaths in the same scenarios. These results may inform the need for more stringent suppression measures as well as efforts to target those at highest risk for a range of preventive interventions.

positive: Long-term Co-existence of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) with Antibody Response in Non-severe Coronavirus Disease 2019 (COVID-19) Patients Severe acute respiratory syndrome coronavirus 2 infection causing coronavirus disease 2019 has spread worldwide. Whether antibodies are important for the adaptive immune responses against SARS-CoV-2 infection needs to be determined. Here, 26 cases of COVID-19 in Jinan, China, were examined and shown to be mild or with common clinical symptoms and no cases of severe symptoms were found among these patients. A striking feature of some patients is that SARS-CoV-2 could exist in patients who have virus-specific IgG antibodies for a very long period, with one case for up to 36 days. One COVID-19 patient who did not produce any SARS-CoV-2-bound IgG successfully cleared SARS-CoV-2 after 46 days of illness, revealing that without antibody-mediated adaptive immunity, innate immunity may still be powerful enough to eliminate SARS-CoV-2. Overall, this report may provide a basis for further analysis of both innate and adaptive immunity in SARS-CoV-2 clearance, especially in non-severe cases. This study also has implications for understanding the pathogenesis and treatment of SARS-CoV-2.

positive: The Innate Immune System: Fighting on the Front Lines or Fanning the Flames of COVID-19? The coronavirus disease 2019 (COVID-19) pandemic caused by SARS-CoV-2 has had devastating global impacts and will continue to have dramatic effects on public health for years to come. A better understanding of the immune response to SARS-CoV-2 will be critical for the application and development of therapeutics. The degree to which the innate immune response confers protection or induces pathogenesis through a dysregulated immune response remains unclear. In this review, we discuss what is known about the role of the innate immune system during SARS-CoV-2 infection, suggest directions for future studies, and evaluate proposed COVID-19 immunomodulating therapeutics.

positive: Presence of SARS-CoV-2 reactive T cells in COVID-19 patients and healthy donors The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a rapidly unfolding pandemic, overwhelming health care systems worldwide1. Clinical manifestations of Corona-virus-disease 2019 (COVID-19) vary broadly, ranging from asymptomatic infection to acute respiratory failure and death2, yet the underlying physiological conditions and mechanisms for this high variability are still unknown. Also, the role of host immune responses in viral clearance and its involvement in pathogenesis remains unresolved. For SARS-CoV (2002/03), however, CD4+ T cell responses are generally associated with positive outcomes3,4, while cellular immune responses to SARS-CoV-2 have not yet been investigated. Here we describe an assay that allows direct detection and characterization of SARS-CoV-2 spike glycoprotein (S)-reactive CD4+ T cells in peripheral blood. We demonstrate the presence of S-reactive CD4+ T cells in 83% of COVID-19 patients, as well as in 34% of SARS-CoV-2 seronegative healthy donors, albeit at lower frequencies. Strikingly, in COVID-19 patients S-reactive CD4+ T cells equally targeted both N-terminal and C-terminal parts of S whereas in healthy donors S-reactive CD4+ T cells reacted almost exclusively to the Cterminal part that is a) characterized by higher homology to spike glycoprotein of human endemic "common cold" coronaviruses, and b) contains the S2 subunit of S with the cytoplasmic peptide (CP), the fusion peptide (FP), and the transmembrane domain (TM) but not the receptor-binding domain (RBD). S-reactive CD4+ T cells from COVID-19 patients were further distinct to those from healthy donors as they co-expressed higher levels of CD38 and HLA-DR, indicating their recent in vivo activation. Our study is the first to directly measure SARS-CoV-2-reactive T cell responses providing critical tools for large scale testing, in depth epitope mapping and characterization of potential cross-reactive cellular immunity to SARS-CoV-2. The presence of pre-existing SARS-CoV-2-reactive T cells in healthy donors is of high interest but larger scale prospective cohort studies are needed to assess whether their presence is a correlate of protection or pathology. Results of such studies will be key for a mechanistic understanding of the SARS-CoV-2 pandemic, adaptation of containment methods and to support vaccine development.

positive: The laboratory tests and host immunity of COVID-19 patients with different severity of illness BACKGROUNDThe coronavirus disease 2019 (COVID-19), infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has caused a severe outbreak throughout the world. The host immunity of COVID-19 patients is unknown.METHODSThe routine laboratory tests and host immunity in COVID-19 patients with different severity of illness were compared after patient admission.RESULTSA total of 65 SARS-CoV-2-positive patients were classified as having mild (n = 30), severe (n = 20), and extremely severe (n = 15) illness. Many routine laboratory tests, such as ferritin, lactate dehydrogenase, and D-dimer, were increased in severe and extremely severe patients. The absolute numbers of CD4+ T cells, CD8+ T cells, and B cells were gradually decreased with increased severity of illness. The activation markers such as HLA-DR and CD45RO expressed on CD4+ and CD8+ T cells were increased in severe and extremely severe patients compared with mild patients. The costimulatory molecule CD28 had opposite results. The percentage of natural Tregs was decreased in extremely severe patients. The percentage of IFN-Î³-producing CD8+ T cells was increased in both severe and extremely severe patients compared with mild patients. The percentage of IFN-Î³-producing CD4+ T cells was increased in extremely severe patients. IL-2R, IL-6, and IL-10 were all increased in extremely severe patients. The activation of DC and B cells was decreased in extremely severe patients.CONCLUSIONThe number and function of T cells are inconsistent in COVID-19 patients. The hyperfunction of CD4+ and CD8+ T cells is associated with the pathogenesis of extremely severe SARS-CoV-2 infection.FUNDINGThis work was funded by the National Mega Project on Major Infectious Disease Prevention (2017ZX10103005-007) and the Fundamental Research Funds for the Central Universities (2019kfyRCPY098).

positive: Antibody responses to SARS-CoV2 are distinct in children with MIS-C compared to adults with COVID-19 Clinical manifestations of COVID-19 caused by the novel coronavirus SARS-CoV-2 are associated with age. While children are largely spared from severe respiratory disease, they can present with a SARS-CoV-2-associated multisystem inflammatory syndrome (MIS-C) similar to Kawasaki's disease. Here, we show distinct antibody (Ab) responses in children with MIS-C compared to adults with severe COVID-19 causing acute respiratory distress syndrome (ARDS), and those who recovered from mild disease. There was a reduced breadth and specificity of anti-SARS-CoV-2-specific antibodies in MIS-C patients compared to the COVID patient groups; MIS-C predominantly generated IgG Abs specific for the Spike (S) protein but not for the nucleocapsid (N) protein, while both COVID-19 cohorts had anti-S IgG, IgM and IgA Abs, as well as anti-N IgG Abs. Moreover, MIS-C patients had reduced neutralizing activity compared to COVID-19 cohorts, indicating a reduced protective serological response. These results suggest a distinct infection course and immune response in children and adults who develop severe disease, with implications for optimizing treatments based on symptom and age.

positive: Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2): An overview of viral structure and host response Abstract Background and aim As a result of its rapid spread in various countries around the world, on March 11, 2020, WHO issued an announcement of the change in coronavirus disease 2019 status from epidemic to pandemic disease. The virus that causes this disease is indicated originating from animals traded in a live animal market in Wuhan, China. Severe Acute Respiratory Syndrome Coronavirus 2 can attack lung cells because there are many conserved receptor entries, namely Angiotensin Converting Enzyme-2. The presence of this virus in host cells will initiate various protective responses leading to pneumonia and Acute Respiratory Distress Syndrome. This review aimed to provide an overview related to this virus and examine the body's responses and possible therapies. Method We searched PubMed databases for Severe Acute Respiratory Syndrome Coronavirus-2, Middle East respiratory syndrome-related coronavirus and Severe Acute Respiratory Syndrome Coronavirus. Full texts were retrieved, analyzed and developed into an easy-to-understand review. Results We provide a complete review related to structure, origin, and how the body responds to this virus infection and explain the possibility of an immune system over-reaction or cytokine storm. We also include an explanation of how this virus creates modes of avoidance to evade immune system attacks. We further explain the therapeutic approaches that can be taken in the treatment and prevention of this viral infection. Conclusion In summary, based on the structural and immune-evasion system of coronavirus, we suggest several approaches to treat the disease.

positive: Induction of protective immunity against coronavirus‐induced encephalomyelitis: Evidence for an important role of CD8(+) T cells in vivo Coronavirus MHV‐JHM infections of rats provide useful models to study the pathogenesis of virus‐induced central nervous system disease. To analyze the role of the immune response against defined MHV‐JHM antigens, we tested the protective efficacy of vaccinia virus (VV) recombinants expressing either the nucleocapsid (N) or the spike (S) protein. A strong protection was mediated in animals by immunization with recombinant VV encoding a wild‐type S protein (VV‐S(Wildtype)), whereas VV recombinant expressing a mutant S(354CR) protein (VV‐S(354CR)) had no protective effect. Recombinant VV encoding N protein (VV‐N) induces a humoral and a CD4(+) T cell response, but did not prevent acute disease regardless of the immunization protocol. In these experiments, challenge with an otherwise lethal dose of MHV‐JHM was performed prior to the induction of virus‐neutralizing antibodies and studies with the anti‐CD8(+) monoclonal antibody, MRC OX8 showed that elimination of the CD8(+) subset of T cells abrogates the protective effect. This result indicates that CD8(+) T cells primed by recombinant VV expressing wild‐type S protein are a primary mechanism of immunological defense against MHV‐JHM infection in rats.

positive: A possible role for B cells in COVID-19?: Lesson from patients with Agammaglobulinemia Summary COVID-19 had a mild clinical course in patients with Agammaglobulinemia lacking B lymphocytes, whereas it developed aggressively in Common Variable Immune Deficiency. Our data offer mechanisms for possible therapeutic targets.

positive: Disruption of Adaptive Immunity Enhances Disease in SARS-CoV-2 Infected Syrian Hamsters Animal models recapitulating human COVID-19 disease, especially with severe disease, are urgently needed to understand pathogenesis and evaluate candidate vaccines and therapeutics. Here, we develop novel severe disease animal models for COVID-19 involving disruption of adaptive immunity in Syrian hamsters. Cyclophosphamide (CyP) immunosuppressed or RAG2 knockout (KO) hamsters were exposed to SARS-CoV-2 by the respiratory route. Both the CyP-treated and RAG2 KO hamsters developed clinical signs of disease that were more severe than in immunocompetent hamsters, notably weight loss, viral loads, and fatality (RAG2 KO only). Disease was prolonged in transiently immunosuppressed hamsters and uniformly lethal in RAG2 KO hamsters. We evaluated the protective efficacy of a neutralizing monoclonal antibody and found that pretreatment, even in immunosuppressed animals, limited infection. Our results suggest that functional B and/or T cells are not only important for the clearance of SARS-CoV-2, but also play an early role in protection from acute disease. One Sentence Summary An antibody targeting the spike protein of SARS-CoV-2 limits infection in immunosuppressed Syrian hamster models.

positive: The SARS-CoV-2 T-cell immunity is directed against the spike, membrane, and nucleocapsid protein and associated with COVID 19 severity Identification of immunogenic targets of SARS-CoV-2 is crucial for monitoring of antiviral immunity and vaccine design. Currently, mainly anti-spike (S)-protein adaptive immunity is investigated. However, also the nucleocapsid (N)- and membrane (M)-proteins should be considered as diagnostic and prophylactic targets. The aim of our study was to explore and compare the immunogenicity of SARS-CoV-2 S-, M- and N-proteins in context of different COVID-19 manifestations. Analyzing a cohort of COVID-19 patients with moderate, severe, and critical disease severity, we show that overlapping peptide pools (OPP) of all three proteins can activate SARS-CoV-2-reactive T-cells with a stronger response of CD4+ compared to CD8+ T-cells. Although interindividual variations for the three proteins were observed, M protein induced the highest frequencies of CD4+ T-cells, suggesting its relevance as diagnostic and vaccination target. Importantly, patients with critical COVID-19 demonstrated the strongest T-cell response, including the highest frequencies of cytokine-producing bi- and trifunctional T-cells, for all three proteins. Although the higher magnitude and superior functionality of SARS-CoV-2-reactive T-cells in critical patients can also be a result of a stronger immunogenicity provided by severe infection, it disproves the hypothesis of insufficient SARS-CoV-2-reactive immunity in critical COVID-19. To this end, activation of effector T-cells with differentiated memory phenotype found in our study could cause hyper-reactive response in critical cases leading to immunopathogenesis. Conclusively, since the S-, M-, and N-proteins induce T-cell responses with individual differences, all three proteins should be evaluated for diagnostics and therapeutic strategies to avoid underestimation of cellular immunity and to deepen our understanding of COVID-19 immunity.

positive: In silico veritas? Potential limitations for SARS-CoV-2 vaccine development based on T-cell epitope prediction

positive: Contributions of the structural proteins of severe acute respiratory syndrome coronavirus to protective immunity. We investigated the contributions of the structural proteins of severe acute respiratory syndrome (SARS) coronavirus (CoV) to protective immunity by expressing them individually and in combinations from a recombinant parainfluenza virus (PIV) type 3 vector called BHPIV3. This vector provided direct immunization of the respiratory tract, the major site of SARS transmission, replication, and disease. The BHPIV3/SARS recombinants were evaluated for immunogenicity and protective efficacy in hamsters, which support a high level of pulmonary SARS-CoV replication. A single intranasal administration of BHPIV3 expressing the SARS-CoV spike protein (S) induced a high titer of SARS-CoV-neutralizing serum antibodies, only 2-fold less than that induced by SARS-CoV infection. The expression of S with the two other putative virion envelope proteins, the matrix M and small envelope E proteins, did not augment the neutralizing antibody response. In absence of S, expression of M and E or the nucleocapsid protein N did not induce a detectable serum SARS-CoV-neutralizing antibody response. Immunization with BHPIV3 expressing S provided complete protection against SARS-CoV challenge in the lower respiratory tract and partial protection in the upper respiratory tract. This was augmented slightly by coexpression with M and E. Expression of M, E, or N in the absence of S did not confer detectable protection. These results identify S among the structural proteins as the only significant SARS-CoV neutralization antigen and protective antigen and show that a single mucosal immunization is highly protective in an experimental animal that supports efficient replication of SARS-CoV.

positive: Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2): An overview of viral structure and host response BACKGROUND AND AIM: As a result of its rapid spread in various countries around the world, on March 11, 2020, WHO issued an announcement of the change in coronavirus disease 2019 status from epidemic to pandemic disease. The virus that causes this disease is indicated originating from animals traded in a live animal market in Wuhan, China. Severe Acute Respiratory Syndrome Coronavirus 2 can attack lung cells because there are many conserved receptor entries, namely Angiotensin Converting Enzyme-2. The presence of this virus in host cells will initiate various protective responses leading to pneumonia and Acute Respiratory Distress Syndrome. This review aimed to provide an overview related to this virus and examine the body's responses and possible therapies. METHOD: We searched PubMed databases for Severe Acute Respiratory Syndrome Coronavirus-2, Middle East respiratory syndrome-related coronavirus and Severe Acute Respiratory Syndrome Coronavirus. Full texts were retrieved, analyzed and developed into an easy-to-understand review. RESULTS: We provide a complete review related to structure, origin, and how the body responds to this virus infection and explain the possibility of an immune system over-reaction or cytokine storm. We also include an explanation of how this virus creates modes of avoidance to evade immune system attacks. We further explain the therapeutic approaches that can be taken in the treatment and prevention of this viral infection. CONCLUSION: In summary, based on the structural and immune-evasion system of coronavirus, we suggest several approaches to treat the disease.

positive: The immunity induced by recombinant spike proteins of SARS coronavirus in Balb/c mice The immune effect of two recombinant protein fragments of spike protein in severe acute respiratory syndrome coronavirus (SARS CoV) was investigated in Balb/c mice. Two partial spike gene fragments S1 (322 1464 bp) and S2 (2170 2814 bp) of SARS coronavirus were amplified by RT-PCR, and cloned into pET-23a prokaryotic expression vector, then transformed into competent Escherichia E. coli BL21 (DE3)(pLysS) respectively. Recombinant proteins were expressed and purified by Ni(2+) immobilized metal ion affinity chromatography. The purified proteins mixed with complete Freund adjuvant were injected into Balb/c mice three times at a two-week interval. High titer antibody was detected in the serum of immunized Balb/c mice, and mice immunized with S1 protein produced high titer IgG1, IgG2a, IgG2b and IgG3, while those immunized with S2 protein produced high titer IgG1, IgG2a, but lower titer IgG2b and IgG3. Serum IFN-concentration was increased significantly but the concentrations of Il-2, IL-4 and IL-10 had no significant change. And a marked increase was observed in the number of spleen CD8+ T cells. The results showed that recombinant proteins of SARS coronavirus spike protein induced hormonal and cellular immune response in Balb/c mice.

positive: SARS-CoV-2 mRNA Vaccine Development Enabled by Prototype Pathogen Preparedness A SARS-CoV-2 vaccine is needed to control the global COVID-19 public health crisis. Atomic-level structures directed the application of prefusion-stabilizing mutations that improved expression and immunogenicity of betacoronavirus spike proteins. Using this established immunogen design, the release of SARS-CoV-2 sequences triggered immediate rapid manufacturing of an mRNA vaccine expressing the prefusion-stabilized SARS-CoV-2 spike trimer (mRNA-1273). Here, we show that mRNA-1273 induces both potent neutralizing antibody and CD8 T cell responses and protects against SARS-CoV-2 infection in lungs and noses of mice without evidence of immunopathology. mRNA-1273 is currently in a Phase 2 clinical trial with a trajectory towards Phase 3 efficacy evaluation.

positive: Yeast-Expressed SARS-CoV Recombinant Receptor-Binding Domain (RBD219-N1) Formulated with Alum Induces Protective Immunity and Reduces Immune Enhancement We developed a severe acute respiratory syndrome (SARS) subunit recombinant protein vaccine candidate based on a highyielding, yeast- engineered, receptor-binding domain (RBD219-N1) of the SARS beta-coronavirus (SARS-CoV) spike (S) protein. When formulated with Alhydrogel®, RBD219-N1 induced high-level neutralizing antibodies against both pseudotyped virus and a clinical (mouse-adapted) isolate of SARS-CoV. Here, we report that mice immunized with RBD219N1/Alhydrogel® were fully protected from lethal SARS-CoV challenge (0% mortality), compared to ~ 30% mortality in mice when immunized with the SARS S protein formulated with Alhydrogel®, and 100% mortality in negative controls. An RBD219-N1 formulation Alhydrogel® was also superior to the S protein, unadjuvanted RBD, and AddaVax (MF59-like adjuvant)-formulated RBD in inducing specific antibodies and preventing cellular infiltrates in the lungs upon SARS-CoV challenge. Specifically, a formulation with a 1:25 ratio of RBD219-N1 to Alhydrogel® provided high neutralizing antibody titers, 100% protection with non-detectable viral loads with minimal or no eosinophilic pulmonary infiltrates. As a result, this vaccine formulation is under consideration for further development against SARS-CoV and other emerging and re-emerging beta-CoVs such as SARS-CoV-2.

positive: Human CD4+ memory T-lymphocyte responses to SARS coronavirus infection Abstract Little is known about CD4+ T-cell immunity to the severe acute respiratory syndrome (SARS) coronavirus. In two SARS patients, we examined the memory CD4+ T-cell responses to peptides derived from SARS coronavirus structural proteins. We generated CD4+ T-cell lines to 3 peptides from the spike (S) protein and defined their HLA restriction. In one patient, the predominant memory CD4+ T-cell response was directed against an epitope outside the S protein receptor-binding domain. In both patients, the frequency of CD4+ memory T-cells to virus structural proteins and anti-SARS coronavirus IgG levels were low by 12 months after infection. This report expands our understanding of the specificity and duration of anti-SARS coronavirus CD4+ T-cell immune responses.

positive: Immune response to SARS-CoV-2 and mechanisms of immunopathological changes in COVID-19 As a zoonotic disease that has already spread globally to several million human beings and possibly to domestic and wild animals, eradication of coronavirus disease 2019 (COVID-19) appears practically impossible. There is a pressing need to improve our understanding of the immunology of this disease to contain the pandemic by developing vaccines and medicines for the prevention and treatment of patients. In this review, we aim to improve our understanding on the immune response and immunopathological changes in patients linked to deteriorating clinical conditions such as cytokine storm, acute respiratory distress syndrome, autopsy findings and changes in acute-phase reactants, and serum biochemistry in COVID-19. Similar to many other viral infections, asymptomatic disease is present in a significant but currently unknown fraction of the affected individuals. In the majority of the patients, a 1-week, self-limiting viral respiratory disease typically occurs, which ends with the development of neutralizing antiviral T cell and antibody immunity. The IgM-, IgA-, and IgG-type virus-specific antibodies levels are important measurements to predict population immunity against this disease and whether cross-reactivity with other coronaviruses is taking place. High viral load during the first infection and repeated exposure to virus especially in healthcare workers can be an important factor for severity of disease. It should be noted that many aspects of severe patients are unique to COVID-19 and are rarely observed in other respiratory viral infections, such as severe lymphopenia and eosinopenia, extensive pneumonia and lung tissue damage, a cytokine storm leading to acute respiratory distress syndrome, and multiorgan failure. Lymphopenia causes a defect in antiviral and immune regulatory immunity. At the same time, a cytokine storm starts with extensive activation of cytokine-secreting cells with innate and adaptive immune mechanisms both of which contribute to a poor prognosis. Elevated levels of acute-phase reactants and lymphopenia are early predictors of high disease severity. Prevention of development to severe disease, cytokine storm, acute respiratory distress syndrome, and novel approaches to prevent their development will be main routes for future research areas. As we learn to live amidst the virus, understanding the immunology of the disease can assist in containing the pandemic and in developing vaccines and medicines to prevent and treat individual patients.

positive: Dysregulation of the immune system as a driver of the critical course of the novel coronavirus disease 2019. Novel coronavirus disease-2019 (COVID-19) is a highly contagious respiratory-related disease induced by the newly emerged virus SARS-CoV-2. Given that inflammatory immune cells may induce severe lung injury, the involvement of immune factors in the pathogenesis of the disease cannot be overestimated. It has been demonstrated that coronaviruses (CoVs) have developed mechanisms of immune evasion, making them invisible to the immune system at an early stage of infection. The mechanism relies on inhibition of the anti-viral response of type I interferons (IFNs), which supports uncontrolled viral replication in epithelial cells. There is growing body of evidence that the fatal hyperinflammation ('cytokine storm') responsible for the severe course of COVID-19 is a consequence of massive SARS-CoV-2 replication rather than inappropriate hyperresponsiveness of the immune system. Therefore, a dampened innate anti-viral immune response seems to be the primary cause of the delayed critical cascade of uncontrolled immune events leading to fulminating systemic inflammation. The occurrence of virus transmission even in asymptomatic subjects infected with SARS-CoV-2 clearly strengthens the evidence for a key role of sufficient immune control of viral replication in a subset of cases (e.g. in children, a population with highly effective innate immune responses). Although administration of immunomodulatory therapeutics is recommended under certain conditions in the guidelines of COVID-19 management, controversies regarding treatment protocols in immunocompromised patients infected with SARS-CoV-2 still exist. Extended knowledge of clinicians on the dysregulated immune response, which is a driver of the COVID-19 outcome, may improve both therapeutic protocols and the prognosis of SARS-CoV-2 infected patients.

positive: Pathogenicity and Viral Shedding of MERS-CoV in Immunocompromised Rhesus Macaques Middle East respiratory syndrome coronavirus (MERS-CoV) has recently emerged in the Middle East. Since 2012, there have been approximately 2,100 confirmed cases, with a 35% case fatality rate. Disease severity has been linked to patient health status, as people with chronic diseases or an immunocompromised status fare worse, although the mechanisms of disease have yet to be elucidated. We used the rhesus macaque model of mild MERS to investigate whether the immune response plays a role in the pathogenicity in relation to MERS-CoV shedding. Immunosuppressed macaques were inoculated with MERS-CoV and sampled daily for 6 days to assess their immune statues and to measure viral shedding and replication. Immunosuppressed macaques supported significantly higher levels of MERS-CoV replication in respiratory tissues and shed more virus, and virus disseminated to tissues outside of the respiratory tract, whereas viral RNA was confined to respiratory tissues in non-immunosuppressed animals. Despite increased viral replication, pathology in the lungs was significantly lower in immunosuppressed animals. The observation that the virus was less pathogenic in these animals suggests that disease has an immunopathogenic component and shows that inflammatory responses elicited by the virus contribute to disease.

positive: Have deaths from COVID-19 in Europe plateaued due to herd immunity?

positive: Priming with rAAV encoding RBD of SARS-CoV S protein and boosting with RBD-specific peptides for T cell epitopes increase T cell responses and provide protection against SRAS-CoV infection Development of vaccines against severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV) is crucial in the prevention of SARS reemergence. The receptor-binding domain (RBD) of SARS-CoV spike (S) protein is an important target in developing safe and effective SARS vaccines. Our previous study has demonstrated that vaccination with adeno-associated virus encoding RBD (RBD-rAAV) induces high titer of neutralizing antibodies. In this study, we further assessed the immune responses and protective effect of the immunization with RBD-rAAV prime/RBD-specific T cell peptide boost, as compared to those of vaccinations with RBD-rAAV and RBD-peptides alone. Our results indicated that RBD-rAAV prime/RBD-peptide boost induced similar Th1 and neutralizing antibody responses, but stronger Th2 and CTL responses than RBD-rAAV prime/boost. The resulting immune responses protected the vaccinated mice from subsequent SARS-CoV challenge, which was evidenced by lower level of viral replication in mouse lung tissues. However, no significant immune responses and protective effect were detected in mice vaccinated with RBD-peptides or blank AAV alone. Since T cell epitopes are highly conserved and boosting with peptides may induce the production of effector memory T cells, our results suggest that the vaccination protocol used may be ideal for providing effective, universal and long-term protection against SARS-CoV infection.

positive: Identification of potential cross-protective epitope between a new type of coronavirus (2019-nCoV) and severe acute respiratory syndrome virus

positive: SARS-CoV-2 seroconversion in health care workers Background The correlates of protection against SARS-CoV-2 and their longevity remain unclear. Studies in severely ill individuals have identified robust cellular and humoral immune responses against the virus. Asymptomatic infection with SARS-CoV-2 has also been described, but it is unknown whether this is sufficient to produce antibody responses. Methods We performed a cross-sectional study recruiting 554 health care workers from University Hospitals Birmingham NHS Foundation Trust who were at work and asymptomatic. Participants were tested for current infection with SARS-CoV-2 by nasopharyngeal swab for real-time polymerase chain reaction and for seroconversion by the measurement of anti-SARS-CoV-2 spike glycoprotein antibodies by enzyme linked immunosorbent assay. Results were interpreted in the context of previous, self-reported symptoms of illness consistent with COVID-19. Results The point prevalence of infection with SARS-CoV-2, determined by the detection of SARS-CoV-2 RNA on nasopharnygeal swab was 2.39% (n=13/544). Serum was available on 516 participants. The overall rate of seroconversion in the cohort was 24.4% (n=126/516). Individuals who had previously experienced a symptomatic illness consistent with COVID-19 had significantly greater seroconversion rates than those who had remained asymptomatic (37.5% vs 17.1%, {chi}2 =21.1034, p<0.0001). In the week preceding peak COVID-19-related mortality at UHBFT, seroconversion rates amongst those who were suffering from symptomatic illnesses peaked at 77.8%. Prior symptomatic illness generated quantitatively higher antibody responses than asymptomatic seroconversion. Seroconversion rates were highest amongst those working in housekeeping (34.5%), acute medicine (33.3%) and general internal medicine (30.3%) with lower rates observed in participants working in intensive care (14.8%) and emergency medicine (13.3%). Conclusions In a large cross-sectional seroprevalence study of health-care workers, we demonstrate that asymptomatic seroconversion occurs, however prior symptomatic illness is associated with quantitatively higher antibody responses. The identification that the potential for seroconversion in health-care workers can associate differentially with certain hospital departments may inform future infection control and occupational health practices.

positive: Could BCG Vaccination Induce Protective Trained Immunity for SARS-CoV-2? Trained immunity is a type of non-specific memory-like immune response induced by some pathogens and vaccines, such as BCG, which can confer antigen-independent protection against a wide variety of pathogens. The BCG vaccine has been extensively used to protect against tuberculosis for almost a 100 years. Interestingly, this vaccine reduces children's mortality caused by infections unrelated to Mycobacterium tuberculosis infection, a phenomenon thought to be due to the induction of trained immunity. The SARS-CoV-2 pandemic has infected, as of April 22, 2020, 2,623,231 people globally, causing a major public health problem worldwide. Currently, no vaccine or treatment is available to control this pandemic. We analyzed the number of positive cases and deaths in different countries and correlated them with the inclusion of BCG vaccination at birth in their national vaccination programs. Interestingly, those countries where BCG vaccination is given at birth have shown a lower contagion rate and fewer COVID-19-related deaths, suggesting that this vaccine may induce trained immunity that could confer some protection for SARS-CoV-2.

positive: Duration of challenge immunity to coronavirus JHM in mice The duration of challenge resistance in mice immunized with mouse hepatitis virus (MHV) strain JHM was examined as a model of immunity to corona-virus infection. Genetically susceptible BALB/cByJ mice were immunized by intranasal (i.n.) or per os (p.o.) inoculation with MHV-JHM or sterile tissue culture fluid (sham) then challenged i.n. with MHV-JHM or sterile tissue culture fluid 1, 6, or 12 months later. Four days after challenge, virus in nasal turbinates and liver was quantified, and prevalance of microscopic lesions in liver and gut-associated lymphoid tissue was tabulated as indices of challenge resistance. MHV-immunized and challenged groups were compared to sham-immunized and challenged groups. Mice immunized by i.n. inoculation were strongly resistant to challenge at 1, 6, and 12 months. Mice immunized by p.o. inoculation were resistant at 1 month, but became partially susceptible to reinfection at 6 and 12 months, based upon all indices. These data indicate that, depending upon route of immunization, mice can become susceptible to reinfection with the same coronavirus strain over time.

positive: Can a herd immunity strategy become a viable option against COVID-19? A model-based analysis on social acceptability and feasibility This paper studies the social acceptability and feasibility of "herd immunity" strategies against coronavirus disease 2019 (COVID-19). To this end, we propose a control scheme that aims to develop herd immunity while satisfying the following two basic requirements for a viable policy option. The first requirement is social acceptability: the overall deaths should be minimized for social acceptance. The second is feasibility: the healthcare system should not be overwhelmed to avoid diverse adverse effects. Exploiting the fact that the severity of the disease increases considerably with age, the proposed control scheme protects high-risk individuals that mainly consist of the elderly. The protection of high-risk individuals reduces the average severity of the disease in the unprotected population, thereby substantially reducing mortality and avoiding the collapse of the healthcare system. Social acceptability (in terms of the resulting mortality) and feasibility (in terms of the healthcare system capacity) of the proposed herd immunity strategy are summarized into two respective, easily computable conditions by building on a simple susceptible--infected--recovered (SIR) model. For its parsimony, the proposed framework can provide a rule of thumb that applies to various populations for studying the viability of herd immunity strategies against COVID-19. For Japan, herd immunity may be developed by the considered control scheme if R0 [≤] 2.0 and the severity rates of the disease are 1/10 times smaller than the previously reported value, although as high mortality as seasonal influenza is expected.

positive: Humoral and cellular immune responses induced by 3a DNA vaccines against severe acute respiratory syndrome (SARS) or SARS-like coronavirus in mice. Vaccine development for severe acute respiratory syndrome coronavirus (SARS-CoV) has mainly focused on the spike (S) protein. However, the variation of the S gene between viruses may affect the efficacy of a vaccine, particularly for cross-protection against SARS-like CoV (SL-CoV). Recently, a more conserved group-specific open reading frame (ORF), the 3a gene, was found in both SARS-CoV and SL-CoV. Here, we studied the immunogenicity of human SARS-CoV 3a and bat SL-CoV 3a DNA vaccines in mice through electroporation immunization followed by enzyme-linked immunosorbent, enzyme-linked immunospot, and flow cytometry assays. Our results showed that high levels of specific humoral responses were induced by SARS-CoV 3a and SL-CoV 3a DNA vaccines. Furthermore, a strong Th1-based cellular immune response was stimulated by both DNA vaccines. The vaccines stimulated gamma interferon production mainly by CD8(+) T cells and interleukin-2 (IL-2) mainly by CD4(+) T cells. Of interest, the frequency of IL-2-positive cells elicited by the SARS-CoV 3a DNA vaccine was significantly higher than that elicited by the SL-CoV 3a DNA vaccine. In summary, our study provides a reference for designing cross-protective DNA vaccines based on the group-specific ORFs of CoVs.

positive: Novel decoy cellular vaccine strategy utilizing transgenic antigen-expressing cells as immune presenter and adjuvant in vaccine prototype against SARS-CoV-2 virus Abstract A novel approach modifying cells to express viral markers to elicit protective immunity responses (decoy cellular vaccination) in the prevention of COVID-19 disease is currently being explored. Our approach entails utilizing SARS-CoV-2 Spike antigen-expressing, non-replicating cells as carriers and presenters of immunogenic antigens, so called “I-cells”. By using irradiated cells as presenting vehicles of SARS-CoV-2 viral antigens(s) in a cellular context, these presented viral proteins can be recognized by the host immune system, thus, an efficient protective immune response might be elicited. Another advantage of this strategy is that the manufacturing process is scalable and yields uniform cell products allowing for “off-the-shelf” frozen supply availability. To prevent engraftment and proliferation of the cells after administration, the cells will be irradiated post-harvesting abolishing in vivo replication potential. Specifically, immunoreactive Spike-1 proteins from SARS-CoV-2 are expressed on the surface of irradiated target I-cells. Utilizing this innovative strategy, these viral antigen-displaying decoy cells will be developed as a vaccine to protect against COVID-19 disease.

positive: Duration of Antibody Responses after Severe Acute Respiratory Syndrome Among 176 patients who had had severe acute respiratory syndrome (SARS), SARS-specific antibodies were maintained for an average of 2 years, and significant reduction of immunoglobulin G–positive percentage and titers occurred in the third year. Thus, SARS patients might be susceptible to reinfection >3 years after initial exposure.

positive: COVID-19 and the immune system. A close interaction between the virus SARS-CoV-2 and the immune system of an individual results in a diverse clinical manifestation of the COVID-19 disease. While adaptive immune responses are essential for SARS-CoV-2 virus clearance, the innate immune cells, such as macrophages, may contribute, in some cases, to the disease progression. Macrophages have shown a significant production of IL-6 suggesting they may contribute to the excessive inflammation in COVID-19 disease. Macrophage Activation Syndrome may further explain the high serum levels of CRP, which are normally lacking in viral infections. In adaptive immune responses, it has been revealed that cytotoxic CD8+ T cells exhibit functional exhaustion patterns, such as the expression of NKG2A, PD-1, and TIM-3. Since SARS-CoV-2 restrains antigen presentation by downregulating MHC class I and II molecules and, therefore, inhibits the T cell-mediated immune responses, humoral immune responses also play a substantial role. Specific IgA response appears to be stronger and more persistent than IgM response. Moreover, IgM and IgG antibodies show similar dynamics in COVID-19 disease.

positive: Blood single cell immune profiling reveals the interferon-MAPK pathway mediated adaptive immune response for COVID-19 The coronavirus disease 2019 (COVID-19) outbreak is an ongoing global health emergence, but the pathogenesis remains unclear. We revealed blood cell immune response profiles using 5' mRNA, TCR and BCR V(D)J transcriptome analysis with single-cell resolution. Data from 134,620 PBMCs and 83,387 TCR and 12,601 BCR clones was obtained, and 56 blood cell subtypes and 23 new cell marker genes were identified from 16 participants. The number of specific subtypes of immune cells changed significantly when compared patients with controls. Activation of the interferon-MAPK pathway is the major defense mechanism, but MAPK transcription signaling is inhibited in cured patients. TCR and BCR V(D)J recombination is highly diverse in generating different antibodies against SARS-CoV-2. Therefore, the interferon-MAPK pathway and TCR- and BCR-produced antibodies play important roles in the COVID-19 immune response. Immune deficiency or immune over-response may result in the condition of patients with COVID-19 becoming critical or severe.

positive: Highly pathogenic coronaviruses: thrusting vaccine development in the spotlight Coronaviruses (CoVs) are a large family of viruses that cause illness ranging from the common cold to more severe diseases such as Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS). Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) disease (COVID-19) has caused major public health crises. There have been more than 4,400,000 reported cases of COVID-2019 and more than 300,000 reported deaths to date (16/05/2020). SARS-CoV, MERS-CoV and SARS-CoV-2 have attracted widespread global attention due to their high infectivity and pathogenicity. To date, there is no specific treatment proven effective against these viral infectious diseases. Vaccination is considered one of the most effective strategies to prevent viral infections. Therefore, the development of effective vaccines against highly pathogenic coronaviruses is essential. In this review, we will briefly describe coronavirus vaccine design targets, summarize recent advances in the development of coronavirus vaccines, and highlight current adjuvants for improving the efficacy of coronavirus vaccines.

positive: Clinical sequelae of the novel coronavirus: does COVID-19 infection predispose patients to cancer? As cancer patients are clinically known to be predisposed to COVID-19 infection, a corollary question of whether COVID-19 infection predisposes to cancer is explored. This article seeks to establish an association between novel coronavirus sequelae and cancer. A literature review on COVID-19 mechanisms of action, molecular responses it elicits upon infection and tumorigenesis pathways is conducted to establish this association. Major signaling pathways implicated in aberrant cellular growth are activated, the ensuing cytokine storm weakens the immune system response to tumors, and patients may develop cancer as a result of superimposed mutagenic and/or carcinogenic events. Future work needs to be performed to support this hypothesis, both in in vitro models and preclinical studies. COVID-19 patients may need to be monitored post-infection for developing cancer.

positive: Type I and Type III IFN Restrict SARS-CoV-2 Infection of Human Airway Epithelial Cultures The newly emerged human coronavirus, SARS-CoV-2, has caused a pandemic of respiratory illness. The innate immune response is critical for protection against Coronaviruses. However, little is known about the interplay between the innate immune system and SARS-CoV-2. Here, we modeled SARS-CoV-2 infection using primary human airway epithelial (pHAE) cultures, which are maintained in an air-liquid interface. We found that SARS-CoV-2 infects and replicates in pHAE cultures and is directionally released on the apical, but not basolateral surface. Transcriptional profiling studies found that infected pHAE cultures had a molecular signature dominated by pro-inflammatory cytokines and chemokine induction, including IL-6, TNFα, CXCL8. We also identified NF-κB and ATF4 transcription factors as key drivers of this pro-inflammatory cytokine response. Surprisingly, we observed a complete lack of a type I or III IFN induction during SARS-CoV-2 infection. Pre-treatment or post-treatment with type I and III IFNs dramatically reduced virus replication in pHAE cultures and this corresponded with an upregulation of antiviral effector genes. Our findings demonstrate that SARS-CoV-2 induces a strong pro-inflammatory cytokine response yet blocks the production of type I and III IFNs. Further, SARS-CoV-2 is sensitive to the effects of type I and III IFNs, demonstrating their potential utility as therapeutic options to treat COVID-19 patients. IMPORTANCE The current pandemic of respiratory illness, COVID-19, is caused by a recently emerged coronavirus named SARS-CoV-2. This virus infects airway and lung cells causing fever, dry cough, and shortness of breath. Severe cases of COVID-19 can result in lung damage, low blood oxygen levels, and even death. As there are currently no vaccines or antivirals approved for use in humans, studies of the mechanisms of SARS-CoV-2 infection are urgently needed. SARS-CoV-2 infection of primary human airway epithelial cultures induces a strong pro-inflammatory cytokine response yet blocks the production of type I and III IFNs. Further, SARS-CoV-2 is sensitive to the effects of type I and III IFNs, demonstrating their potential utility as therapeutic options to treat COVID-19 patients.

positive: Duration of serum neutralizing antibodies for SARS-CoV-2: Lessons from SARS-CoV infection

positive: IFITM-Family Proteins: The Cell's First Line of Antiviral Defense. Animal cells use a wide variety of mechanisms to slow or prevent replication of viruses. These mechanisms are usually mediated by antiviral proteins whose expression and activities can be constitutive but are frequently amplified by interferon induction. Among these interferon-stimulated proteins, members of the IFITM (interferon-induced transmembrane) family are unique because they prevent infection before a virus can traverse the lipid bilayer of the cell. At least three human IFITM proteins-IFITM1, IFITM2, and IFITM3-have antiviral activities. These activities limit infection in cultured cells by many viruses, including dengue virus, Ebola virus, influenza A virus, severe acute respiratory syndrome coronavirus, and West Nile virus. Murine Ifitm3 controls influenza A virus infection in vivo, and polymorphisms in human IFITM3 correlate with the severity of both seasonal and highly pathogenic avian influenza virus. Here we review the discovery and characterization of the IFITM proteins, describe the spectrum of their antiviral activities, and discuss potential mechanisms underlying these effects.

positive: Preliminary Identification of Potential Vaccine Targets for the COVID-19 Coronavirus (SARS-CoV-2) Based on SARS-CoV Immunological Studies The beginning of 2020 has seen the emergence of COVID-19 outbreak caused by a novel coronavirus, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). There is an imminent need to better understand this new virus and to develop ways to control its spread. In this study, we sought to gain insights for vaccine design against SARS-CoV-2 by considering the high genetic similarity between SARS-CoV-2 and SARS-CoV, which caused the outbreak in 2003, and leveraging existing immunological studies of SARS-CoV. By screening the experimentally-determined SARS-CoV-derived B cell and T cell epitopes in the immunogenic structural proteins of SARS-CoV, we identified a set of B cell and T cell epitopes derived from the spike (S) and nucleocapsid (N) proteins that map identically to SARS-CoV-2 proteins. As no mutation has been observed in these identified epitopes among the 120 available SARS-CoV-2 sequences (as of 21 February 2020), immune targeting of these epitopes may potentially offer protection against this novel virus. For the T cell epitopes, we performed a population coverage analysis of the associated MHC alleles and proposed a set of epitopes that is estimated to provide broad coverage globally, as well as in China. Our findings provide a screened set of epitopes that can help guide experimental efforts towards the development of vaccines against SARS-CoV-2.

positive: Immune responses and pathogenesis in persistently PCR‐positive patients with SARS‐CoV‐2 infection Coronavirus disease (COVID‐19) caused by SARS‐CoV‐2 emerged in China in December 2019 and then rapidly spread worldwide. Why COVID‐19 patients with the same clinical condition have different outcomes remains unclear. This study aimed to examine the differences in the phenotype and functions of major populations of immune cells between COVID‐19 patients with same severity but different outcomes. Four common type adult inpatients with laboratory confirmed COVID‐19 from Beijing YouAn Hospital, Capital Medical University were included in this study. The patients were divided into two groups based on whether or not COVID‐19 PCR‐negative conversion occurred within three weeks. Peripheral blood samples were collected to compare the differences in the phenotype and functions of major populations of immune cells between the two groups of patients. The result shows that the proportions of CD3(+)CD8(+)CD38(+)HLA‐DR(+)CD27(‐) effector T killer cells generally declined, whereas that of CD3(+)CD4(+)CD8(+) double‐positive T cells (DPTs) increased in the persistently PCR‐positive patients. In summary, considering the imbalance between effector T killer cells/ CD3+CD4+CD8+ DPTs was a possible key factor for PCR‐negative conversion in COVID‐19 patients. This article is protected by copyright. All rights reserved.

positive: Nucleocapsid protein from porcine epidemic diarrhea virus isolates can antagonize interferon-λ production by blocking the nuclear factor-κB nuclear translocation Porcine epidemic diarrhea virus (PEDV) is a highly infectious pathogen that can cause severe diseases in pigs and result in enormous economic losses in the worldwide swine industry. Previous studies revealed that PEDV exhibits an obvious capacity for modulating interferon (IFN) signaling or expression. The newly discovered type III IFN, which plays a crucial role in antiviral immunity, has strong antiviral activity against PEDV proliferation in IPEC-J2 cells. In this study, we aimed to investigate the effect of PEDV nucleocapsid (N) protein on type III IFN-λ. We found that the N proteins of ten PEDV strains isolated between 2013 and 2017 from different local farms shared high nucleotide identities, while the N protein of the CV777 vaccine strain formed a monophyletic branch in the phylogenetic tree. The N protein of the epidemic strain could antagonize type III IFN, but not type I or type II IFN expression induced by polyinosinic-polycytidylic acid (poly(I:C)) in IPEC-J2 cells. Subsequently, we demonstrated that the inhibition of poly(I:C)- induced IFN-λ3 production by PEDV N protein was dependent on the blocking of nuclear factor-κB (NF-κB) nuclear translocation. These findings might help increase understanding of the pathogenesis of PEDV and its mechanisms for evading the host immune response.

positive: Rapid generation of neutralizing antibody responses in COVID-19 patients SARS-CoV-2 is currently causing a devastating pandemic and there is a pressing need to understand the dynamics, specificity, and neutralizing potency of the humoral immune response during acute infection. Herein, we report the dynamics of antibody responses to the receptor-binding domain (RBD) of the spike protein and virus neutralization activity in 44 COVID-19 patients. RBD-specific IgG responses were detectable in all patients 6 days after PCR confirmation. Using a clinical isolate of SARS-CoV-2, neutralizing antibody titers were also detectable in all patients 6 days after PCR confirmation. The magnitude of RBD-specific IgG binding titers correlated strongly with viral neutralization. In a clinical setting, the initial analysis of the dynamics of RBD-specific IgG titers was corroborated in a larger cohort of PCR-confirmed patients (n=231). These findings have important implications for our understanding of protective immunity against SARS-CoV-2, the use of immune plasma as a therapy, and the development of much-needed vaccines.

positive: New IgM seroconversion and positive RT‐PCR test after exposure to the virus in recovered COVID‐19 patient To date, understanding whether acquired immunity and presence of anti SARS‐Cov2 antibodies protects against reinfection is one the most important focus of the scientific community [1‐2]. Several studies suggest that acquired immunity may protect upon further exposure to SARS‐COV2 [3‐6]. Contrary to this picture, we describe a case of a patient recovered from COVID‐19 pneumonia with positive serology, followed up by 6 negative nasopharyngeal swab‐PCR tests performed along 1 month, who later on, after exposure to the virus, presented another positive RT‐PCR test and a second IgM seroconversion. This report opens up several possible interpretations. This article is protected by copyright. All rights reserved.

positive: Antibody Tests in Detecting SARS-CoV-2 Infection: A Meta-Analysis The emergence of Coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 made imperative the need for diagnostic tests that can identify the infection. Although Nucleic Acid Test (NAT) is considered to be the gold standard, serological tests based on antibodies could be very helpful. However, individual studies are usually inconclusive, thus, a comparison of different tests is needed. We performed a systematic review and meta-analysis in PubMed, medRxiv and bioRxiv. We used the bivariate method for meta-analysis of diagnostic tests pooling sensitivities and specificities. We evaluated IgM and IgG tests based on Enzyme-linked immunosorbent assay (ELISA), Chemiluminescence Enzyme Immunoassays (CLIA), Fluorescence Immunoassays (FIA), and the Lateral Flow Immunoassays (LFIA). We identified 38 studies containing data from 7848 individuals. Tests using the S antigen are more sensitive than N antigen-based tests. IgG tests perform better compared to IgM ones and show better sensitivity when the samples were taken longer after the onset of symptoms. Moreover, a combined IgG/IgM test seems to be a better choice in terms of sensitivity than measuring either antibody alone. All methods yield high specificity with some of them (ELISA and LFIA) reaching levels around 99%. ELISA- and CLIA-based methods perform better in terms of sensitivity (90%–94%) followed by LFIA and FIA with sensitivities ranging from 80% to 89%. ELISA tests could be a safer choice at this stage of the pandemic. LFIA tests are more attractive for large seroprevalence studies but show lower sensitivity, and this should be taken into account when designing and performing seroprevalence studies.

positive: Antibody-Dependent Cellular Phagocytosis in Antiviral Immune Responses Antiviral activities of antibodies may either be dependent only on interactions between the antibody and cognate antigen, as in binding and neutralization of an infectious virion, or instead may require interactions between antibody–antigen immune complexes and immunoproteins or Fc receptor expressing immune effector cells. These Fc receptor-dependent antibody functions provide a direct link between the innate and adaptive immune systems by combining the potent antiviral activity of innate effector cells with the diversity and specificity of the adaptive humoral response. The Fc receptor-dependent function of antibody-dependent cellular phagocytosis (ADCP) provides mechanisms for clearance of virus and virus-infected cells, as well as for stimulation of downstream adaptive immune responses by facilitating antigen presentation, or by stimulating the secretion of inflammatory mediators. In this review, we discuss the properties of Fc receptors, antibodies, and effector cells that influence ADCP. We also provide and interpret evidence from studies that support a potential role for ADCP in either inhibiting or enhancing viral infection. Finally, we describe current approaches used to measure antiviral ADCP and discuss considerations for the translation of studies performed in animal models. We propose that additional investigation into the role of ADCP in protective viral responses, the specific virus epitopes targeted by ADCP antibodies, and the types of phagocytes and Fc receptors involved in ADCP at sites of virus infection will provide insight into strategies to successfully leverage this important immune response for improved antiviral immunity through rational vaccine design.

positive: Temporal Dynamics of Co-circulating Lineages of Porcine Reproductive and Respiratory Syndrome Virus Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) is the most important endemic pathogen in the U.S. swine industry. Despite control efforts involving improved biosecurity and different vaccination protocols, the virus continues to circulate and evolve. One of the foremost challenges in its control is high levels of genetic and antigenic diversity. Here, we quantify the co-circulation, emergence and sequential turnover of multiple PRRSV lineages in a single swine-producing region in the United States over a span of 9 years (2009–2017). By classifying over 4,000 PRRSV sequences (open-reading frame 5) into phylogenetic lineages and sub-lineages, we document the ongoing diversification and temporal dynamics of the PRRSV population, including the rapid emergence of a novel sub-lineage that appeared to be absent globally pre-2008. In addition, lineage 9 was the most prevalent lineage from 2009 to 2010, but its occurrence fell to 0.5% of all sequences identified per year after 2014, coinciding with the emergence or re-emergence of lineage 1 as the dominant lineage. The sequential dominance of different lineages, as well as three different sub-lineages within lineage 1, is consistent with the immune-mediated selection hypothesis for the sequential turnover in the dominant lineage. As host populations build immunity through natural infection or vaccination toward the most common variant, this dominant (sub-) lineage may be replaced by an emerging variant to which the population is more susceptible. An analysis of patterns of non- synonymous and synonymous mutations revealed evidence of positive selection on immunologically important regions of the genome, further supporting the potential that immune-mediated selection shapes the evolutionary and epidemiological dynamics for this virus. This has important implications for patterns of emergence and re-emergence of genetic variants of PRRSV that have negative impacts on the swine industry. Constant surveillance on PRRSV occurrence is crucial to a better understanding of the epidemiological and evolutionary dynamics of co-circulating viral lineages. Further studies utilizing whole genome sequencing and exploring the extent of cross-immunity between heterologous PRRS viruses could shed further light on PRRSV immunological response and aid in developing strategies that might be able to diminish disease impact.

positive: Potent binding of 2019 novel coronavirus spike protein by a SARS coronavirus-specific human monoclonal antibody The newly identified 2019 novel coronavirus (2019-nCoV) has caused more than 11,900 laboratory-confirmed human infections, including 259 deaths, posing a serious threat to human health. Currently, however, there is no specific antiviral treatment or vaccine. Considering the relatively high identity of receptor-binding domain (RBD) in 2019-nCoV and SARS-CoV, it is urgent to assess the cross-reactivity of anti-SARS CoV antibodies with 2019-nCoV spike protein, which could have important implications for rapid development of vaccines and therapeutic antibodies against 2019-nCoV. Here, we report for the first time that a SARS-CoV-specific human monoclonal antibody, CR3022, could bind potently with 2019-nCoV RBD (KD of 6.3 nM). The epitope of CR3022 does not overlap with the ACE2 binding site within 2019-nCoV RBD. These results suggest that CR3022 may have the potential to be developed as candidate therapeutics, alone or in combination with other neutralizing antibodies, for the prevention and treatment of 2019-nCoV infections. Interestingly, some of the most potent SARS-CoV-specific neutralizing antibodies (e.g. m396, CR3014) that target the ACE2 binding site of SARS-CoV failed to bind 2019-nCoV spike protein, implying that the difference in the RBD of SARS-CoV and 2019-nCoV has a critical impact for the cross-reactivity of neutralizing antibodies, and that it is still necessary to develop novel monoclonal antibodies that could bind specifically to 2019-nCoV RBD.

positive: COVID-19: Pathogenesis, cytokine storm and therapeutic potential of interferons ABSTRACT The outbreak of the novel SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) responsible for coronavirus disease 2019 (COVID-19) has developed into a major health hazard across the globe. The rapid escalation of the COVID-19 and the considerable associated illness leading to death has transformed it into a critical global public health issue. The current clinical investigation in patients with COVID-19 has showed strong upregulation of cytokine and interferon production after critical infection with SARS-CoV2- induced pneumonia. The current research suggests that few groups of patients with COVID-19 might have a cytokine storm syndrome. Thus, identification and treatment of hyperinflammation using existing, approved therapies with proven safety profiles to address the immediate need to reduce the rising mortality. To date, no specific therapeutic drug or vaccine has been discovered to treat this COVID-19. Intensive research is in progress to identify a promising drug therapy. Hence, several options were proposed to control this fast-emerging pandemic, including antiviral drugs, vaccines, small-molecules, monoclonal antibodies, oligonucleotides, peptides, and interferons (IFNs).

positive: Could Coronavirus Disease 2019 (COVID-19) Render Natural Immunity to Re-infections? A Spotlight on the Therapeutic Pipeline

positive: The COVID-19 Serology Studies Workshop: Recommendations and Challenges Summary The development, validation and appropriate application of serological assays to detect antibodies to SARS-CoV-2 are essential to determining seroprevalence of this virus in the United States and globally and in guiding government leadership and the private sector on back-to-work policies. An interagency working group of the U.S. Department of Health and Human Services convened a virtual workshop to identify knowledge gaps and key outstanding scientific issues and to develop strategies to fill them. Key outcomes of the Workshop included recommendations for: 1) advancing serology assays as a tool to better understand SARS-CoV-2 infection; and 2) conducting crucial serology field studies to advance an understanding of immunity to SARS-CoV-2 leading to protection and duration of protection, including the correlation between serological test results and risk of reinfection.

positive: Immunoinformatic analysis of the SARS-CoV-2 envelope protein as a strategy to assess cross-protection against COVID-19 Envelope protein of coronaviruses is a structural protein existing in both monomeric and homo-pentameric form. It has been related to a multitude of roles including virus infection, replication, dissemination and immune response stimulation. In the present study, we employed an immunoinformatic approach to investigate the major immunogenic domains of the SARS-CoV-2 envelope protein and map them among the homologue proteins of coronaviruses with tropism for animal species that are closely inter-related with the human beings population all over the world. Also, when not available, we predicted the envelope protein structural folding and mapped SARS-CoV-2 epitopes. Envelope sequences alignment provides evidence of high sequence homology for some of the investigated virus specimens; while the structural mapping of epitopes resulted in the interesting maintenance of the structural folding and epitope sequence localization also in the envelope proteins scoring a lower alignment score. In line with the One-Health approach, our evidences provide a molecular structural rationale for a potential role of taxonomically related coronaviruses in conferring protection from SARS-CoV-2 infection and identifying potential candidates for the development of diagnostic tools and prophylactic-oriented strategies.

positive: Immune responses and pathogenesis of SARS-CoV-2 during an outbreak in Iran: Comparison with SARS and MERS The beginning of 2020 has seen the emergence of COVID-19, an outbreak caused by a novel coronavirus, SARS-CoV-2, an important pathogen for humans. There is an urgent need to better understand this new virus and to develop ways to control its spread. In Iran, the first case of the COVID-19 was reported after spread from China and other countries. Fever, cough, and fatigue were the most common symptoms of this virus. In worldwide, the incubation period of COVID-19 was 3 to 7 days and approximately 80% of infections are mild or asymptomatic, 15% are severe, requiring oxygen, and 5% are critical infections, requiring ventilation. To mount an antiviral response, the innate immune system recognizes molecular structures that are produced by the invasion of the virus. COVID-19 infection induces IgG antibodies against N protein that can be detected by serum as early as day 4 after the onset of disease and with most patients seroconverting by day 14. Laboratory evidence of clinical patients showed that a specific T-cell response against SARS-CoV-2 is important for the recognition and killing of infected cells, particularly in the lungs of infected individuals. At present, there is no specific antiviral therapy for COVID-19 and the main treatments are supportive. In this review, we investigated the innate and acquired immune responses in patients who recovered from COVID-19, which could inform the design of prophylactic vaccines and immunotherapy for the future.

positive: Introduction of neutralizing immunogenicity index to the rational design of MERS coronavirus subunit vaccines Viral subunit vaccines often contain immunodominant non-neutralizing epitopes that divert host immune responses. These epitopes should be eliminated in vaccine design, but there is no reliable method for evaluating an epitope's capacity to elicit neutralizing immune responses. Here we introduce a new concept ‘neutralizing immunogenicity index' (NII) to evaluate an epitope's neutralizing immunogenicity. To determine the NII, we mask the epitope with a glycan probe and then assess the epitope's contribution to the vaccine's overall neutralizing immunogenicity. As proof-of-concept, we measure the NII for different epitopes on an immunogen comprised of the receptor-binding domain from MERS coronavirus (MERS-CoV). Further, we design a variant form of this vaccine by masking an epitope that has a negative NII score. This engineered vaccine demonstrates significantly enhanced efficacy in protecting transgenic mice from lethal MERS-CoV challenge. Our study may guide the rational design of highly effective subunit vaccines to combat MERS-CoV and other life-threatening viruses.

positive: Single-cell landscape of bronchoalveolar immune cells in patients with COVID-19 Respiratory immune characteristics associated with Coronavirus Disease 2019 (COVID-19) severity are currently unclear. We characterized bronchoalveolar lavage fluid immune cells from patients with varying severity of COVID-19 and from healthy people by using single-cell RNA sequencing. Proinflammatory monocyte-derived macrophages were abundant in the bronchoalveolar lavage fluid from patients with severe COVID-9. Moderate cases were characterized by the presence of highly clonally expanded CD8+ T cells. This atlas of the bronchoalveolar immune microenvironment suggests potential mechanisms underlying pathogenesis and recovery in COVID-19.

positive: SARS-CoV-2 IgG Antibody Responses in New York City Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is a strain of coronavirus that causes coronavirus disease 2019 (Covid-19) and has been declared a global pandemic by the World Health Organization. Total cases of SARS-CoV-2 worldwide exceed 4.8 million, with over 320,000 deaths recorded. Little is known about the body's immune response to SARS-CoV-2 infection. In this paper, we describe SARS-CoV-2 IgG antibody responses in 11,092 patients from the New York City metropolitan area and report a SARS-CoV-2 IgG positivity rate of nearly 50%, indicating the widespread nature of the pandemic in the city and state of New York. Additionally, we report on the correlation between SARS-CoV-2 patient symptom severity and level of SARS-CoV-2 IgG antibody found in the patient sample.

positive: Validation of a SARS-CoV-2 spike protein ELISA for use in contact investigations and sero-surveillance Since emergence of SARS-CoV-2 in late 2019, there has been a critical need to understand prevalence, transmission patterns, to calculate the burden of disease and case fatality rates. Molecular diagnostics, the gold standard for identifying viremic cases, are not ideal for determining true case counts and rates of asymptomatic infection. Serological detection of SARS-CoV-2 specific antibodies can contribute to filling these knowledge gaps. In this study, we describe optimization and validation of a SARS-CoV-2-specific-enzyme linked immunosorbent assay (ELISA) using the prefusion-stabilized form of the spike protein [1]. We performed receiver operator characteristic (ROC) analyses to define the specificities and sensitivities of the optimized assay and examined cross reactivity with immune sera from persons confirmed to have had infections with other coronaviruses. These assays will be used to perform contact investigations and to conduct large-scale, cross sectional surveillance to define disease burden in the population.

positive: SARS-CoV-2: virus dynamics and host response

positive: Herd immunity – estimating the level required to halt the COVID-19 epidemics in affected countries

positive: Persistent viral RNA positivity during recovery period of a patient with SARS‐CoV‐2 infection As an emerging infectious disease, the clinical course and virological course of SARS‐CoV‐2 infection remain to be further investigated. In this case report, we described a case of SARS‐CoV‐2 infection with clinical course more than two months. This patient had recovered from the pneumonia after treatment. The viral RNA of throat swabs became negative and the viral specific antibodies were produced during recovery period. However, the viral RNA reappeared and additionally persisted in throat swabs for more than 40 days. In addition, the viral RNA was detected in multiple types of specimens with extremely high titers in the saliva. In conclusion, these findings indicate that SARS‐CoV‐2 can cause a long clinical course. The coexistence of viral RNA and viral specific antibodies may imply an immune evasion of SARAS‐CoV‐2 from host's immune system. This article is protected by copyright. All rights reserved.

positive: The spike protein of SARS-CoV — a target for vaccine and therapeutic development Severe acute respiratory syndrome (SARS) is a newly emerging infectious disease caused by a novel coronavirus, SARS-coronavirus (SARS-CoV). The SARS-CoV spike (S) protein is composed of two subunits; the S1 subunit contains a receptor-binding domain that engages with the host cell receptor angiotensin-converting enzyme 2 and the S2 subunit mediates fusion between the viral and host cell membranes. The S protein plays key parts in the induction of neutralizing-antibody and T-cell responses, as well as protective immunity, during infection with SARS-CoV. In this Review, we highlight recent advances in the development of vaccines and therapeutics based on the S protein.

positive: Prior infection by seasonal coronaviruses does not prevent SARS-CoV-2 infection and associated Multisystem Inflammatory Syndrome in children Background: Children have a lower rate of COVID-19, potentially related to cross-protective immunity conferred by seasonal coronaviruses (HCoVs). We tested if prior infections with seasonal coronaviruses impacted SARS-CoV-2 infections and related Multisystem Inflammatory Syndrome (MIS). Methods: This cross-sectional observational study in Paris hospitals enrolled 739 pauci or asymptomatic children (HOS group) plus 36 children with suspected MIS (MIS group). Prevalence, antigen specificity and neutralizing capability of SARS-CoV-2 antibodies were tested. Antibody frequency and titres against Nucleocapsid (N) and Spike (S) of the four seasonal coronaviruses (NL63, HKU1, 229E, OC43) were measured in a subset of seropositive patients (54 SARS-CoV-2 (HOS-P subgroup) and 15 MIS (MIS-P subgroup)), and in 118 matched SARS-CoV-2 seronegative patients (CTL subgroup). Findings: SARS-CoV-2 mean prevalence rate in HOSP children was 11.7% from April 1 to June 1. Neutralizing antibodies were found in 55.6% of seropositive children, and their relative frequency increased with time (up to 100 % by mid-May). A majority of MIS children (25/36) were SARS-CoV-2 seropositive, of which all tested (n=15) had neutralizing antibodies. On average, seropositive MIS children had higher N and S1 SARS-CoV-2 titres as compared to HOS children. Patients from HOS-P, MIS-P, and CTL subgroups had a similar prevalence of antibodies against the four seasonal HCoVs (66.9 -100%). The level of anti-SARS-CoV-2 antibodies was not significantly different in children who had prior seasonal coronavirus infection. Interpretation: Prior infection with HCoVs does not prevent SARS-CoV-2 infection and related MIS in children. Children develop neutralizing antibodies after SARS-CoV-2 infection.

positive: Longitudinal high-throughput TCR repertoire profiling reveals the dynamics of T cell memory formation after mild COVID-19 infection COVID-19 is a global pandemic caused by the SARS-CoV-2 coronavirus. The T cell response is a critical part of both individual and herd immunity to SARS-CoV-2 and the efficacy of developed vaccines. However neither the dynamics and cross-reactivity of the SARS-CoV-2-specific T cell response nor the diversity of resulting immune memory are well understood. In this study we use longitudinal high-throughput T cell receptor sequencing to track changes in the T cell repertoire following two mild cases of COVID-19 infection. In both donors we identified SARS-CoV-2-responding CD4+ and CD8+ T cell clones. We describe characteristic motifs in TCR sequences of COVID-19-reactive clones, suggesting the existence of immunodominant epitopes. We show that in both donors the majority of infection-reactive clonotypes acquire memory phenotypes. Certain CD4+ clones were detected in the memory fraction at the pre-infection timepoint, suggesting participation of pre-existing cross-reactive memory T cells in the immune response to SARS-CoV-2.

positive: Respiratory virus-induced heterologous immunity: Part of the problem or part of the solution? PURPOSE: To provide current knowledge on respiratory virus-induced heterologous immunity (HI) with a focus on humoral and cellular cross-reactivity. Adaptive heterologous immune responses have broad implications on infection, autoimmunity, allergy and transplant immunology. A better understanding of the mechanisms involved might ultimately open up possibilities for disease prevention, for example by vaccination. METHODS: A structured literature search was performed using Medline and PubMed to provide an overview of the current knowledge on respiratory-virus induced adaptive HI. RESULTS: In HI the immune response towards one antigen results in an alteration of the immune response towards a second antigen. We provide an overview of respiratory virus-induced HI, including viruses such as respiratory syncytial virus (RSV), rhinovirus (RV), coronavirus (CoV) and influenza virus (IV). We discuss T cell receptor (TCR) and humoral cross-reactivity as mechanisms of HI involving those respiratory viruses. Topics covered include HI between respiratory viruses as well as between respiratory viruses and other pathogens. Newly developed vaccines which have the potential to provide protection against multiple virus strains are also discussed. Furthermore, respiratory viruses have been implicated in the development of autoimmune diseases, such as narcolepsy, Guillain–Barré syndrome, type 1 diabetes or myocarditis. Finally, we discuss the role of respiratory viruses in asthma and the hygiene hypothesis, and review our recent findings on HI between IV and allergens, which leads to protection from experimental asthma. CONCLUSION: Respiratory-virus induced HI may have protective but also detrimental effects on the host. Respiratory viral infections contribute to asthma or autoimmune disease development, but on the other hand, a lack of microbial encounter is associated with an increasing number of allergic as well as autoimmune diseases. Future research might help identify the elements which determine a protective or detrimental outcome in HI-based mechanisms.

positive: Proposal for vaccination against SARS coronavirus using avian infectious bronchitis virus strain H from The Netherlands

positive: SARS coronavirus pathogenesis: host innate immune responses and viral antagonism of interferon SARS-CoV is a pathogenic coronavirus that emerged from a zoonotic reservoir, leading to global dissemination of the virus. The association SARS-CoV with aberrant cytokine, chemokine, and Interferon Stimulated Gene (ISG) responses in patients provided evidence that SARS-CoV pathogenesis is at least partially controlled by innate immune signaling. Utilizing models for SARS-CoV infection, key components of innate immune signaling pathways have been identified as protective factors against SARS-CoV disease, including STAT1 and MyD88. Gene transcription signatures unique to SARS-CoV disease states have been identified, but host factors that regulate exacerbated disease phenotypes still remain largely undetermined. SARS-CoV encodes several proteins that modulate innate immune signaling through the antagonism of the induction of Interferon and by avoidance of ISG effector functions.

positive: Progress and Challenges toward the Development of Vaccines against Avian Infectious Bronchitis Avian infectious bronchitis (IB) is a widely distributed poultry disease that has huge economic impact on poultry industry. The continuous emergence of new IBV genotypes and lack of cross protection among different IBV genotypes have been an important challenge. Although live attenuated IB vaccines remarkably induce potent immune response, the potential risk of reversion to virulence, neutralization by the maternal antibodies, and recombination and mutation events are important concern on their usage. On the other hand, inactivated vaccines induce a weaker immune response and may require multiple dosing and/or the use of adjuvants that probably have potential safety risks and increased economic burdens. Consequently, alternative IB vaccines are widely sought. Recent advances in recombinant DNA technology have resulted in experimental IB vaccines that show promise in antibody and T-cells responses, comparable to live attenuated vaccines. Recombinant DNA vaccines have also been enhanced to target multiple serotypes and their efficacy has been improved using delivery vectors, nanoadjuvants, and in ovo vaccination approaches. Although most recombinant IB DNA vaccines are yet to be licensed, it is expected that these types of vaccines may hold sway as future vaccines for inducing a cross protection against multiple IBV serotypes.

positive: COVID-19 herd immunity strategies: walking an elusive and dangerous tightrope The rapid growth in cases of COVID-19 has threatened to overwhelm healthcare systems in multiple countries. In response, severely affected countries have had to consider a range of public health strategies achieved by implementing non-pharmaceutical interventions. Broadly, these strategies have fallen into two categories: i) “mitigation”, which aims to achieve herd immunity by allowing the SARS-CoV-2 virus to spread through the population while mitigating disease burden, and ii) “suppression”, aiming to drastically reduce SARS-CoV-2 transmission rates and halt endogenous transmission in the target population. Using an age-structured transmission model, parameterised to simulate SARS-CoV-2 transmission in the UK, we assessed the prospects of success using both of these approaches. We simulated a range of different non-pharmaceutical intervention scenarios incorporating social distancing applied to differing age groups. We found that it is possible to suppress SARS-CoV-2 transmission if social distancing measures are sustained at a sufficient level for a period of months. Our modelling did not support achieving herd immunity as a practical objective, requiring an unlikely balancing of multiple poorly-defined forces. Specifically, we found that: i) social distancing must initially reduce the transmission rate to within a narrow range, ii) to compensate for susceptible depletion, the extent of social distancing must be vary over time in a precise but unfeasible way, and iii) social distancing must be maintained for a long duration (over 6 months).

positive: Manipulation of Intestinal Antiviral Innate Immunity and Immune Evasion Strategies of Porcine Epidemic Diarrhea Virus Porcine epidemic diarrhea virus (PEDV) infection causes watery diarrhea, dehydration, and high mortality in neonatal pigs, due to its clinical pathogenesis of the intestinal mucosal barrier dysfunction. The host's innate immune system is the first line of defence upon virus invasion of the small intestinal epithelial cells. In turn, the virus has evolved to modulate the host's innate immunity during infection, resulting in pathogen virulence, survival, and the establishment of successful infection. In this review, we gather current knowledge concerning the interplay between PEDV and components of host innate immunity, focusing on the role of cytokines and interferons in intestinal antiviral innate immunity, and the mechanisms underlying the immune evasion strategies of PEDV invasion. Finally, we provide some perspectives on the potential prevention and treatment for PEDV infection.

positive: SARS-CoV-2-A Tough Opponent for the Immune System Coronaviruses recently returned with a new one, SARS-CoV-2, related to a potentially severe respiratory disease-called the coronavirus disease (COVID-19). Research shows that the SARS-CoV-2 can be clustered with the Bat SARS-like coronavirus. Bats possess an additional, innate ability for antiviral defense, and, on the other hand, the potential to go hand-in-hand with the virus to generate variability. Besides the high potential of the novel coronavirus in compromising the respiratory system, its rapid transmission and ability to engage many hosts in severe forms of infections or immunopathological complications make it a tough opponent for the immune system. The interactions between SARS-CoV2 and the host immune system result in unleashing tremendous amounts of cytokines, and these cytokines make a storm that would determine the outcome (recovery or death) of the lungs of the patient.

positive: MERS-CoV: Understanding the Latest Human Coronavirus Threat Human coronaviruses cause both upper and lower respiratory tract infections in humans. In 2012, a sixth human coronavirus (hCoV) was isolated from a patient presenting with severe respiratory illness. The 60-year-old man died as a result of renal and respiratory failure after admission to a hospital in Jeddah, Saudi Arabia. The aetiological agent was eventually identified as a coronavirus and designated Middle East respiratory syndrome coronavirus (MERS-CoV). MERS-CoV has now been reported in more than 27 countries across the Middle East, Europe, North Africa and Asia. As of July 2017, 2040 MERS-CoV laboratory confirmed cases, resulting in 712 deaths, were reported globally, with a majority of these cases from the Arabian Peninsula. This review summarises the current understanding of MERS-CoV, with special reference to the (i) genome structure; (ii) clinical features; (iii) diagnosis of infection; and (iv) treatment and vaccine development.

positive: Increased litter survival rates, reduced clinical illness and better lactogenic immunity against TGEV in gilts that were primed as neonates with porcine respiratory coronavirus (PRCV) Abstract Establishing immunological memory in female piglets at a young age with PRCV was effective in inducing a secondary immune response to a limiting dose of virulent TGEV given orally 13–18 days prior to farrowing. Subsequently, because of passive antibody transfer, the offspring of these primed gilts were more efficient in surviving a lethal TGEV challenge. An average survival rate of 89% occurred in 6 litters of piglets from primed gilts that were boosted with 2.8×106 plaque forming units (PFU) of TGEV whereas 76% of the piglets survived in three litters that suckled primed gilts boosted with 3.0×105 PFU of TGEV. Non-primed gilts given identical pre-farrowing doses of TGEV had litter survival rates of 63 and 55%, respectively. Moreover, both groups of litters from primed gilts suffered less clinical illness (as measured by the extent of weight loss post-challenge) than control litters. Priming of the piglets as neonates and boosting the pregnant gilts produced an anamnestic systemic immune response and correspondingly higher milk titers in the primed gilts compared to control animals. Thus, priming piglets with PRCV was beneficial in providing resistance to TGEV and could be incorporated into a vaccine strategy that yields better protection against TGEV.

positive: Two-Year Prospective Study of the Humoral Immune Response of Patients with Severe Acute Respiratory Syndrome In a cohort study of 56 convalescent patients with severe acute respiratory syndrome (SARS), titers of immunoglobulin G (IgG) antibodies and neutralizing antibodies (NAbs) against SARS-associated coronavirus were assessed at regular intervals (at 1, 4, 7, 10, 16, and 24 months after the onset of disease) by use of enzyme-linked immunosorbent assay and neutralization assay. IgG antibody and NAb titers were highly correlated, peaking at month 4 after the onset of disease and decreasing thereafter. IgG antibodies remained detectable in all patients until month 16, and they became undetectable in 11.8% of patients at month 24. The finding that NAbs remained detectable throughout follow-up is reassuring in terms of protection provided against reinfection; however, NAb titers decreased markedly after month 16

positive: DNA Vaccine Encoding Middle East Respiratory Syndrome Coronavirus S1 Protein Induces Protective Immune Responses in Mice The Middle East respiratory syndrome coronavirus (MERS-CoV), is an emerging pathogen that continues to cause outbreaks in the Arabian peninsula and in travelers from this region, raising the concern that a global pandemic could occur. Here, we show that a DNA vaccine encoding the first 725 amino acids (S1) of MERS-CoV spike (S) protein induces antigen-specific humoral and cellular immune responses in mice. With three immunizations, high titers of neutralizing antibodies (up to 1: 10(4)) were generated without adjuvant. DNA vaccination with the MERS-CoV S1 gene markedly increased the frequencies of antigen-specific CD4(+) and CD8(+) T cells secreting IFN-γ and other cytokines. Both pcDNA3.1-S1 DNA vaccine immunization and passive transfer of immune serum from pcDNA3.1-S1 vaccinated mice protected Ad5-hDPP4-transduced mice from MERS-CoV challenge. These results demonstrate that a DNA vaccine encoding MERS-CoV S1 protein induces strong protective immune responses against MERS-CoV infection.

positive: COVID-19: Immunology and treatment options The novel coronavirus SARS-CoV2 causes COVID-19, a pandemic threatening millions. As protective immunity does not exist in humans and the virus is capable of escaping innate immune responses, it can proliferate, unhindered, in primarily infected tissues. Subsequent cell death results in the release of virus particles and intracellular components to the extracellular space, which result in immune cell recruitment, the generation of immune complexes and associated damage. Infection of monocytes/macrophages and/or recruitment of uninfected immune cells can result in massive inflammatory responses later in the disease. Uncontrolled production of pro-inflammatory mediators contributes to ARDS and cytokine storm syndrome. Antiviral agents and immune modulating treatments are currently being trialled. Understanding immune evasion strategies of SARS-CoV2 and the resulting delayed massive immune response will result in the identification of biomarkers that predict outcomes as well as phenotype and disease stage specific treatments that will likely include both antiviral and immune modulating agents.

positive: Detection of SARS-CoV-2-Specific Humoral and Cellular Immunity in COVID-19 Convalescent Individuals The World Health Organization has declared SARS-CoV-2 virus outbreak a worldwide pandemic. However, there is very limited understanding on the immune responses, especially adaptive immune responses to SARS-CoV-2 infection. Here, we collected blood from COVID-19 patients who have recently become virus-free, and therefore were discharged, and detected SARS-CoV-2-specific humoral and cellular immunity in eight newly discharged patients. Follow-up analysis on another cohort of six patients 2 weeks post discharge also revealed high titers of immunoglobulin G (IgG) antibodies. In all 14 patients tested, 13 displayed serum-neutralizing activities in a pseudotype entry assay. Notably, there was a strong correlation between neutralization antibody titers and the numbers of virus-specific T cells. Our work provides a basis for further analysis of protective immunity to SARS-CoV-2, and understanding the pathogenesis of COVID-19, especially in the severe cases. It also has implications in developing an effective vaccine to SARS-CoV-2 infection.

positive: Sequence-based prediction of vaccine targets for inducing T cell responses to SARS-CoV-2 utilizing the bioinformatics predictor RECON Background The ongoing COVID-19 pandemic has created an urgency to identify novel vaccine targets for protective immunity against SARS-CoV-2. Consistent with observations for SARS-CoV, a closely related coronavirus responsible for the 2003 SARS outbreak, early reports identify a protective role for both humoral and cell-mediated immunity for SARS CoV-2. Methods In this study, we leveraged HLA-I and HLA-II T cell epitope prediction tools from RECON® (Real-time Epitope Computation for ONcology), our bioinformatic pipeline that was developed using proteomic profiling of individual HLA-I and HLA-II alleles to predict rules for peptide binding to a diverse set of such alleles. We applied these binding predictors to viral genomes from the Coronaviridae family, and specifically to identify SARS-CoV-2 T cell epitopes. Results To test the suitability of these tools to identify viral T cell epitopes, we first validated HLA-I and HLA-II predictions on Coronaviridae family epitopes deposited in the Virus Pathogen Database and Analysis Resource (ViPR) database. We then use our HLA-I and HLA-II predictors to identify 11,776 HLA-I and 7,991 HLA-II candidate binding peptides across all 12 open reading frames (ORFs) of SARS-CoV-2. This extensive list of identified candidate peptides is driven by the length of the ORFs and the significant number of HLA-I and HLA-II alleles that we are able to predict (74 and 83, respectively), providing over 99% coverage for the US, European and Asian populations, for both HLA-I and HLA-II. From our SARS-CoV-2 predicted peptide-HLA-I allele pairs, 368 pairs identically matched previously reported pairs in the ViPR database, originating from other forms of coronaviruses. 320 of these pairs (89.1%) had a positive MHC-binding assay result. This analysis reinforces the validity our predictions. Conclusions Using this bioinformatic platform, we identify multiple putative epitopes for CD4+ and CD8+ T cells whose HLA binding properties cover nearly the entire population and thus may be effective when included in prophylactic vaccines against SARS-CoV-2 to induce broad cellular immunity.

positive: Private specificities of CD8 T cell responses control patterns of heterologous immunity CD8 T cell cross-reactivity between viruses can play roles in protective heterologous immunity and damaging immunopathology. This cross-reactivity is sometimes predictable, such as between lymphocytic choriomeningitis virus (LCMV) and Pichinde virus, where cross-reactive epitopes share six out of eight amino acids. Here, however, we demonstrate more subtle and less predictable cross-reactivity between LCMV and the unrelated vaccinia virus (VV). Epitope-specific T cell receptor usage differed between individual LCMV-infected C57BL/6 mice, even though the mice had similar epitope-specific T cell hierarchies. LCMV-immune mice challenged with VV showed variations, albeit in a distinct hierarchy, in proliferative expansions of and down-regulation of IL-7Rα by T cells specific to different LCMV epitopes. T cell responses to a VV-encoded epitope that is cross-reactive with LCMV fluctuated greatly in VV-infected LCMV-immune mice. Adoptive transfers of splenocytes from individual LCMV-immune donors resulted in nearly identical VV-induced responses in each of several recipients, but responses differed depending on the donor. This indicates that the specificities of T cell responses that are not shared between individuals may influence cross-reactivity with other antigens and play roles in heterologous immunity upon encounter with another pathogen. This variability in cross-reactive T cell expansion that is unique to the individual may underlie variation in the pathogenesis of infectious diseases.

positive: Measuring SARS-CoV-2 neutralizing antibody activity using pseudotyped and chimeric viruses The emergence of SARS-CoV-2 and the ensuing explosive epidemic of COVID19 disease has generated a need for assays to rapidly and conveniently measure the antiviral activity of SARSCoV-2-specific antibodies. Here, we describe a collection of approaches based on SARS-CoV-2 spike-pseudotyped, single-cycle, replication-defective human immunodeficiency virus type-1 (HIV-1) and vesicular stomatitis virus (VSV), as well as a replication-competent VSV/SARS-CoV-2 chimeric virus. While each surrogate virus exhibited subtle differences in the sensitivity with which neutralizing activity was detected, the neutralizing activity of both convalescent plasma and human monoclonal antibodies measured using each virus correlated quantitatively with neutralizing activity measured using an authentic SARS-CoV-2 neutralization assay. The assays described herein are adaptable to high throughput and are useful tools in the evaluation of serologic immunity conferred by vaccination or prior SARS-CoV-2 infection, as well as the potency of convalescent plasma or human monoclonal antibodies.

positive: RNA‐virus proteases counteracting host innate immunity Virus invasion triggers host immune responses, in particular, innate immune responses. Pathogen‐associated molecular patterns of viruses (such as dsRNA, ssRNA, or viral proteins) released during virus replication are detected by the corresponding pattern‐recognition receptors of the host, and innate immune responses are induced. Through production of type‐I and type‐III interferons as well as various other cytokines, the host innate immune system forms the frontline to protect host cells and inhibit virus infection. Not surprisingly, viruses have evolved diverse strategies to counter this antiviral system. In this review, we discuss the multiple strategies used by proteases of positive‐sense single‐stranded RNA viruses of the families Picornaviridae, Coronaviridae, and Flaviviridae, when counteracting host innate immune responses.

positive: Role of China in the Quest to Define and Control Severe Acute Respiratory Syndrome China holds the key to solving many questions crucial to global control of severe acute respiratory syndrome (SARS). The disease appears to have originated in Guangdong Province, and the causative agent, SARS coronavirus, is likely to have originated from an animal host, perhaps sold in public markets. Epidemiologic findings, integral to defining an animal-human linkage, may then be confirmed by laboratory studies; once animal host(s) are confirmed, interventions may be needed to prevent further animal-to-human transmission. Community seroprevalence studies may help determine the basis for the decline in disease incidence in Guangdong Province after February 2002. China will also be able to contribute key data about how the causative agent is transmitted and how it is evolving, as well as identifying pivotal factors influencing disease outcome. There must be support for systematically addressing these fundamental questions in China and rapidly disseminating results.

positive: The early antibody response to SARS-Cov-2 infection.

positive: Dysregulation of the immune system as a driver of the critical course of the novel coronavirus disease 2019 Novel coronavirus disease-2019 (COVID-19) is a highly contagious respiratory-related disease induced by the newly emerged virus SARS-CoV-2. Given that inflammatory immune cells may induce severe lung injury, the involvement of immune factors in the pathogenesis of the disease cannot be overestimated. It has been demonstrated that coronaviruses (CoVs) have developed mechanisms of immune evasion, making them invisible to the immune system at an early stage of infection. The mechanism relies on inhibition of the anti-viral response of type I interferons (IFNs), which supports uncontrolled viral replication in epithelial cells. There is growing body of evidence that the fatal hyperinflammation ('cytokine storm') responsible for the severe course of COVID-19 is a consequence of massive SARS-CoV-2 replication rather than inappropriate hyperresponsiveness of the immune system. Therefore, a dampened innate anti-viral immune response seems to be the primary cause of the delayed critical cascade of uncontrolled immune events leading to fulminating systemic inflammation. The occurrence of virus transmission even in asymptomatic subjects infected with SARS-CoV-2 clearly strengthens the evidence for a key role of sufficient immune control of viral replication in a subset of cases (e.g. in children, a population with highly effective innate immune responses). Although administration of immunomodulatory therapeutics is recommended under certain conditions in the guidelines of COVID-19 management, controversies regarding treatment protocols in immunocompromised patients infected with SARS-CoV-2 still exist. Extended knowledge of clinicians on the dysregulated immune response, which is a driver of the COVID-19 outcome, may improve both therapeutic protocols and the prognosis of SARS-CoV-2 infected patients.

positive: Humoral and circulating follicular helper T cell responses in recovered patients with COVID-19 The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has dramatically expedited global vaccine development efforts1–3, most targeting the viral ‘spike’ glycoprotein (S) S localizes on the virion surface and mediates recognition of cellular receptor angiotensin-converting enzyme 2 (ACE2)4–6 Eliciting neutralizing antibodies that block S–ACE2 interaction7–9, or indirectly prevent membrane fusion10, constitute an attractive modality for vaccine-elicited protection11 However, although prototypic S-based vaccines show promise in animal models12–14, the immunogenic properties of S in humans are poorly resolved In this study, we characterized humoral and circulating follicular helper T cell (cTFH) immunity against spike in recovered patients with coronavirus disease 2019 (COVID-19) We found that S-specific antibodies, memory B cells and cTFH are consistently elicited after SARS-CoV-2 infection, demarking robust humoral immunity and positively associated with plasma neutralizing activity Comparatively low frequencies of B cells or cTFH specific for the receptor binding domain of S were elicited Notably, the phenotype of S-specific cTFH differentiated subjects with potent neutralizing responses, providing a potential biomarker of potency for S-based vaccines entering the clinic Overall, although patients who recovered from COVID-19 displayed multiple hallmarks of effective immune recognition of S, the wide spectrum of neutralizing activity observed suggests that vaccines might require strategies to selectively target the most potent neutralizing epitopes

positive: SARS-coronavirus replication in human peripheral monocytes/macrophages Abstract A novel coronavirus (CoV) has been described in association with cases of severe acute respiratory syndrome (SARS). The virus, SARS-CoV, differs from the previously described human coronaviruses, 229E and OC43. 229E was previously shown to productively infect human monocytes/macrophages, whereas OC43 poorly infected the cells. In this study, we examined whether SARS-CoV could productively infect purified monocytes/macrophages (PM) derived from human donor cells. Unlike 229E-infected cells, which produced viral titers of 103.5 to 106 TCID50/ml, SARS-CoV replicated poorly in PM, producing titers of 101.75 to 102 TCID50/ml. This finding was similar to results reported for OC43-infected cells, with titers ranging from 101.2 to 102.7 TCID50/ml. Of interest, SARS-CoV proteins were detected only in PM that did not produce significant amounts of interferon (IFN)-α, and in one such case, preliminary electron microscope studies demonstrated that SARS-CoV-like particles could enter the cells, possibly via phagocytosis. These results suggest that SARS-CoV, like human CoV OC43, poorly infects human PM, and production of IFN-α by these cells further limits the infection. Given the importance of monocytes/macrophages to the immune response, it is possible that their infection by SARS-CoV and alteration of this infection by IFN-α may be important to the course of the infection in humans.

positive: The phenotypic changes of Î³Î´ T cells in COVID-19 patients A novel pneumonia-associated respiratory syndrome named coronavirus disease-2019 (COVID-19), which caused by SARS-CoV-2 and broken in Wuhan, China in the end of 2019. Unfortunately, there is no specific antiviral agent or vaccine available to treat SARS-CoV-2 infections. Also, information regarding the immunological characteristics in COVID-19 patients remains limited. Here we collected the blood samples from 18 healthy donors (HD) and 38 COVID-19 patients to analyze changes in {gamma}{delta} T cells. In comparison to HD, the {gamma}{delta} T cells percentage was decreased. {gamma}{delta} T cells are able to immediately respond to SARS-CoV-2 infection and upregulate the activation marker CD25. In addition, the increased expression of CD4 in {gamma}{delta} T cells may serve as a biomarker for the assessment of SARS-CoV-2 infection.

positive: The potential role of Th17 immune responses in coronavirus immunopathology and vaccine-induced immune enhancement Increasing evidence points to host Th17 inflammatory responses as contributing to the severe lung pathology and mortality of lower respiratory tract infections from coronaviruses. This includes host inflammatory and cytokine responses to COVID-19 caused by the SARS-2 coronavirus (SARS CoV2). From studies conducted in laboratory animals, there are additional concerns about immune enhancement and the role of potential host immunopathology resulting from experimental human COVID-19 vaccines. Here we summarize evidence suggesting there may be partial overlap between the underlying immunopathologic processes linked to both coronavirus infection and vaccination, and a role for Th17 in immune enhancement and eosinophilic pulmonary immunopathology. Such findings help explain the link between viral-vectored coronavirus vaccines and immune enhancement and its reduction through alum adjuvants. Additional research may also clarify links between COVID-19 pulmonary immunopathology and heart disease.

positive: Host Immune Responses to SARS Coronavirus in Humans The severe acute respiratory syndrome (SARS) is a newly identified infectious disease caused by a novel zoonotic coronavirus (SARS-CoV) with unknown animal reservoirs. The risk of SARS reemergence in humans remains high due to the large animal reservoirs of SARS-CoV-like coronavirus and the genome instability of RNA coronaviruses. An epidemic in 2003 affected more than 8,000 patients in 29 countries, with 10% mortality. SARS infection is transmitted by air droplets. Clinical and laboratory manifestations include fever, chills, rigor, myalgia, malaise, diarrhea, cough, dyspnoea, pneumonia, lymphopenia, neutrophilia, thrombocytopenia, and elevated serum lactate dehydrogenase, alanine aminotransferase, and creatine kinase activities. Health care workers are a high-risk group, and advanced age is strongly associated with disease severity. Treatment has been empirical, and there is no licensed SARS vaccine for humans so far. However, presence of long-lived neutralizing antibodies and memory T- and B-lymphocytes in convalescent SARS patients raises hope for active immunization. Furthermore, results from preclinical SARS vaccines expressing spike protein to elicit neutralizing antibodies and cellular responses that are protective in mouse and nonhuman primate models are encouraging. Very little is known of the early events in viral clearance and the onset of innate and inflammatory responses during the SARS infection. Regulation of the innate immune response is associated with the development of adaptive immunity and disease severity in SARS infection. Notably, SARS-CoV has evolved evasive strategies to suppress antiviral type I interferon responses in infected cells. In addition, inflammatory responses are characterized by upregulation of proinflammatory cytokines/chemokines such as IL-6, IP-10, and MCP-1 in tissues and serum, and massive infiltrations of inflammatory cells such as macrophages in infected tissues. Due to the lack of animal models that mimic the clinical manifestations of human SARS infection for mechanistic study and vaccine evaluation, development of a safe prophylactic SARS vaccine for human use remains a huge challenge. This chapter is written to summarize and highlight the latest clinical, serological, and immunological parameters relevant to the pathogenesis and protective immunity of SARS infection in humans.

positive: Understanding the T cell immune response in SARS coronavirus infection The severe acute respiratory syndrome (SARS) epidemic started in late 2002 and swiftly spread across 5 continents with a mortality rate of around 10%. Although the epidemic was eventually controlled through the implementation of strict quarantine measures, there continues a need to investigate the SARS coronavirus (SARS-CoV) and develop interventions should it re-emerge. Numerous studies have shown that neutralizing antibodies against the virus can be found in patients infected with SARS-CoV within days upon the onset of illness and lasting up to several months. In contrast, there is little data on the kinetics of T cell responses during SARS-CoV infection and little is known about their role in the recovery process. However, recent studies in mice suggest the importance of T cells in viral clearance during SARS-CoV infection. Moreover, a growing number of studies have investigated the memory T cell responses in recovered SARS patients. This review covers the available literature on the emerging importance of T cell responses in SARS-CoV infection, particularly on the mapping of cytotoxic T lymphocyte (CTL) epitopes, longevity, polyfunctionality and human leukocyte antigen (HLA) association as well as their potential implications on treatment and vaccine development.

positive: Distinct Inductions of and Responses to Type I and Type III Interferons Promote Infections in Two SARS-CoV-2 Isolates The recent emerging coronavirus, SARS-CoV-2, has been rapidly and widely spread and causing an ongoing viral pneumonia outbreak worldwide. It has been observed that SARS-CoV-2 patients show a rather long and asymptomatic incubation time. We characterized the abilities to induce and to response to IFNβ/IFNλ1 of two or our clinical isolates, SARS-CoV-2/NTU01/TWN/human/2020 and SARS-CoV-2/NTU02/TWN/human/2020, which exhibit only two amino acid differences over the ∼30kb viral genome. We found that both isolates may infect Huh7, A549 and Calu-3 cells, yet the RIG-I-like receptor-dependent antiviral signaling was poorly induced in these cells in the early infections. Unexpectedly, we found that the intracellular vRNA levels of these isolates were sustained upon to type I/III IFN treatments, and this phenotype was more pronounced in the Taiwan/NTU01/2020 isolate. The type I/III IFN responses are antiviral but partially proviral in the case of SARS-CoV-2 infections. Poor induction and response to innate immunity may contribute to destitute neutralization index of the antibody produced, and indeed we found that the patient serum could not efficiently neutralize SARS-CoV-2 virions. With better understandings of the interplay between SARS-CoV-2 and the host antiviral innate immunity, our report may provide new insights for the regimen of therapies for SARS-CoV-2 infected patients.

positive: Antiviral Innate Immunity: Introduction ☆ Abstract The concept of “innate immunity” includes all sorts of measures that exclude, inhibit, or slow down infections with little specificity and without much adaptation or generation of a long-lasting memory. The mammalian innate immune defenses described in this article comprise defensins, the complement system, nonspecific phagocytic and cytolytic leukocytes, and cytokines such as the antivirally active interferons. Since the type I (IFN-α/β) and type III interferon (IFN-λ) systems are our primary defense against viral infections, special attention will be paid to the virus-triggered induction of IFN transcription, the signaling activated by IFNs, and the antiviral factors expressed as a consequence.

positive: Strategies for vaccine design for corona virus using Immunoinformatics techniques The cutting-edge technology vaccinomics is the combination of two topics immunogenetics and immunogenomics with the knowledge of systems biology and immune profiling for designing vaccine against infectious disease. In our present study, an epitope-based peptide vaccine against nonstructural protein 4 of beta coronavirus, using a combination of B cell and T cell epitope predictions, followed by molecular docking methods are performed. Here, protein sequences of homologous nonstructural protein 4 of beta coronavirus are collected and conserved regions present in them are investigated via phylogenetic study to determine the most immunogenic part of protein. From the identified region of the target protein, the peptide sequence IRNTTNPSAR from the region ranging from 38-47 and the sequence PTDTYTSVYLGKFRG from the positions of 76-90 are considered as the most potential B cell and T cell epitopes respectively. Furthermore, this predicted T cell epitopes PTDTYTSVY and PTDTYTSVYLGKFRG interacted with MHC allelic proteins HLA-A*01:01 and HLA-DRB5*01:01 respectively with the low IC50 values. These epitopes are perfectly fitted into the epitope binding grooves of alpha helix of MHC I molecule and MHC II molecule with binding energy scores −725.0 Kcal/mole and −786.0 Kcal/mole respectively, showing stability in MHC molecules binding. This MHC restricted epitope PTDTYTSVY also showed a good conservancy of 50.16% in world population coverage. This MHC I HLA-A*01:01 allele is present among 58.87% of Chinese population also. Therefore, the epitopes IRNTTNPSAR and PTDTYTSVYLGKFRG may be considered as potential peptides for peptide-based vaccine for coronavirus after further experimental study.

positive: Receptor-binding domain of SARS-CoV spike protein induces long-term protective immunity in an animal model Development of effective vaccines against severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV) is still a priority in prevention of re-emergence of SARS. Our previous studies have shown that the receptor-binding domain (RBD) of SARS-CoV spike (S) protein elicits highly potent neutralizing antibody responses in the immunized animals. But it is unknown whether RBD can also induce protective immunity in an animal model, a key aspect for vaccine development. In this study, BALB/c mice were vaccinated intramuscularly (i.m.) with 10 μg of RBD-Fc (RBD fused with human IgG1 Fc) and boosted twice at 3-week intervals and one more time at 12th month. Humoral immune responses of vaccinated mice were investigated for up to 12 months at a 1-month interval and the neutralizing titers of produced antibodies were reported at months 0, 3, 6 and 12 post-vaccination. Mice were challenged with the homologous strain of SARS-CoV 5 days after the last boost, and sacrificed 5 days after the challenge. Mouse lung tissues were collected for detection of viral load, virus replication and histopathological effects. Our results showed that RBD-Fc vaccination induced high titer of S-specific antibodies with long-term and potent SARS-CoV neutralizing activity. Four of five vaccinated mice were protected from subsequent SARS-CoV challenge because no significant virus replication, and no obvious histopathological changes were found in the lung tissues of the vaccinated mice challenged with SARS-CoV. Only one vaccinated mouse had mild alveolar damage in the lung tissues. In contrast, high copies of SARS-CoV RNA and virus replication were detected, and pathological changes were observed in the lung tissues of the control mice. In conclusion, our findings suggest that RBD, which can induce protective antibodies to SARS-CoV, may be further developed as a safe and effective SARS subunit vaccine.

positive: Immune phenotyping based on neutrophil-to-lymphocyte ratio and IgG predicts disease severity and outcome for patients with COVID-19 Background: A recently emerging respiratory disease named coronavirus disease 2019 (COVID-19) has quickly spread across the world. This disease is initiated by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and uncontrolled cytokine storm, but it remains unknown as to whether a robust antibody response is related to clinical deterioration and poor outcome in laboratory-confirmed COVID-19 patients. Methods: Anti-SARS-CoV-2 IgG and IgM antibodies were determined by chemiluminescence analysis (CLIA) in COVID-19 patients from a single center in Wuhan. Median IgG and IgM levels in acute and convalescent-phase sera (within 35 days) for all included patients were calculated and compared among severe and nonsevere patients. Immune response phenotyping based on late IgG levels and neutrophil-to-lymphocyte ratio (NLR) was characterized to stratify patients with different disease severities and outcome. Laboratory parameters in patients with different immune response phenotypes and disease severities were analyzed. Findings: A total of 222 patients were included in this study. IgG was first detected on day 4 of illness, and its peak levels occurred in the fourth week. Severe cases were more frequently found in patients with high IgG levels, compared to those who with low IgG levels (51.8% versus 32.3%; p=0.008). Severity rates for patients with NLRhiIgGhi, NLRhiIgGlo, NLRloIgGhi, and NLRloIgGlo phenotype was 72.3%, 48.5%, 33.3%, and 15.6%, respectively (p<0.0001). Furthermore, severe patients with NLRhiIgGhi, NLRhiIgGlo had higher proinflammatory cytokines levels including IL-2, IL-6 and IL-10, and decreased CD4+ T cell count compared to those with NLRloIgGlo phenotype (p<0.05). Recovery rate for severe patients with NLRhiIgGhi, NLRhiIgGlo, NLRloIgGhi, and NLRloIgGlo phenotype was 58.8% (20/34), 68.8% (11/16), 80.0% (4/5), and 100% (12/12), respectively (p=0.0592). Dead cases only occurred in NLRhiIgGhi and NLRhiIgGlo phenotypes. Interpretation: COVID-19 severity is associated with increased IgG response, and an immune response phenotyping based on late IgG response and NLR could act as a simple complementary tool to discriminate between severe and nonsevere COVID-19 patients, and further predict their clinical outcome.

positive: The Role of T Cell Epitopes in Coronavirus Infection Multiple MHV-specific CD4 and CD8 T cell epitopes have been identified in C57Bl/6 and BALB/c mice. In particular, at least two CD8 T cell epitopes are recognized in C57Bl/6 mice. In one model of MHV persistence, mutations are detected in the immunodominant CD8 T cell epitope recognized in this strain. These mutations contribute to virus persistence and to the development of more severe clinical disease.

positive: COVID-19, an emerging coronavirus infection: advances and prospects in designing and developing vaccines, immunotherapeutics, and therapeutics The novel coronavirus infection (COVID-19 or Coronavirus disease 2019) that emerged from Wuhan, Hubei province of China has spread to many countries worldwide. Efforts have been made to develop vaccines against human coronavirus (CoV) infections such as MERS and SARS in the past decades. However, to date, no licensed antiviral treatment or vaccine exists for MERS and SARS. Most of the efforts for developing CoV vaccines and drugs target the spike glycoprotein or S protein, the major inducer of neutralizing antibodies. Although a few candidates have shown efficacy in in vitro studies, not many have progressed to randomized animal or human trials, hence may have limited use to counter COVID-19 infection. This article highlights ongoing advances in designing vaccines and therapeutics to counter COVID-19 while also focusing on such experiences and advances as made with earlier SARS- and MERS-CoVs, which together could enable efforts to halt this emerging virus infection.

positive: Severe acute respiratory syndrome (SARS) coronavirus: application of monoclonal antibodies and development of an effective vaccine SARS‐CoV is a new type of human coronavirus identified as a causative agent of severe acute respiratory syndrome (SARS). On the occasion of the SARS outbreak, various monoclonal antibodies (mAbs) against SARS‐CoV have been developed and applied for diagnosis, clinical management and basic research. In this review, we overview the biochemical and functional properties and applications of these SARS‐CoV mAbs. We also focus on a variety of vaccines currently under development and discuss the immune response elicited by these vaccines in animal models, hopefully to better understand what we need to do next to fight against newly emerging pathogens in the future. Copyright © 2006 John Wiley & Sons, Ltd.

positive: Influence of maternal immunity on the outcome of mutine coronavirus JHM infection in suckling mice Adult C3H mice are resistant to intraperitoneal infection with murine coronavirus JHM, whereas suckling offspring of non-immune females are susceptible. Resistance can be conferred on suckling C3H mice by postnatal transmission of maternal immunity, if transfer preceeds infection. Suckling mice succumb to infection even when they receive maternal antibodies within 1 day after infection. Prenatal transmission alone without subsequent postnatal transmission of maternal immunity is not sufficient to provide resistance. Persistence of virus without clinical consequences was observed when the supply of breast milk anti-JHMV antibodies was terminated 5 days before infection. Immune reactions restricted by histocompatibility antigens do not play a crucial role in bestowing resistance. As neutralizing anti-JHM serum antibody titers of adult mice only rise sharply 5 to 7 days after infection, these results indicate that infection of adults can be arrested by immunological means but that, in addition, the rate of virus dissemination must be limited by other non-immunological mechanisms.

positive: Cytokine Storm in COVID-19 patients transforms to a Cytokine Super Cyclone in patients with risk factors The seventh human coronavirus SARS-CoV2 belongs to the cluster of extremely pathogenic coronaviruses like SARS-CoV and MERS-CoV, which are established to cause lower respiratory tract infection. The viral infection can be fatal as the disease advances to pneumonia followed by acute respiratory distress syndrome (ARDS). Increasingly higher cytokine concentration on account of over-stimulated immune response against the virus, or the ‘cytokine storm’, is the reason behind the manifestation of lethal clinical symptoms. In this article, we discuss the immune pathogenesis of cytokine storm and its relation with SARS-CoV2/COVID-19 risk factors. People with underlying risk factors are more susceptible to fatal complications of COVID-19 infection leading to poor clinical outcome. The increased pro-inflammatory immune status in patients with risk factors (diabetes, hypertension, cardiovascular disease, COPD) exacerbates the Cytokine-storm of COVID-19 to a Cytokine Super Cyclone. We also overviewed antiviral immune response provided by BCG vaccine involving the IL-1β, IL-6 and TNF-α secretion via ‘trained monocytes’, which confers early protection against SARS-CoV2.

positive: A global effort to define the human genetics of protective immunity to SARS-CoV-2 infection Abstract SARS-CoV-2 infection displays immense inter-individual clinical variability, ranging from silent infection to lethal disease. The role of human genetics in determining clinical response to the virus remains unclear. Studies of outliers – individuals remaining uninfected despite viral exposure and healthy young patients with life-threatening disease – presents a unique opportunity to reveal human genetic determinants of infection and disease.

positive: Two X-linked agammaglobulinemia patients develop pneumonia as COVID-19 manifestation but recover BACKGROUND: The recent SARS-CoV-2 pandemic, which has recently affected Italy since February 21, constitutes a threat to normal subjects, as the coronavirus disease-19 (COVID-19) can manifest with a broad spectrum of clinical phenotypes ranging from asymptomatic cases to pneumonia or even death. There is evidence that older age and several comorbidities can affect the risk to develop severe pneumonia and possibly the need of mechanic ventilation in subjects infected with SARS-CoV-2. Therefore, we evaluated the outcome of SARS-CoV-2 infection in patients with inborn errors of immunity (IEI) such as X-linked agammaglobulinemia (XLA). METHODS: When the SARS-CoV-2 epidemic has reached Italy, we have activated a surveillance protocol of patients with IEI, to perform SARS-CoV-2 search by nasopharyngeal swab in patients presenting with symptoms that could be a manifestation of COVID-19, such as fever, cough, diarrhea, or vomiting. RESULTS: We describe two patients with X-linked agammaglobulinemia (XLA) aged 34 and 26 years with complete absence of B cells from peripheral blood who developed COVID-19, as diagnosed by SARS-CoV-2 detection by nasopharyngeal swab, while receiving immunoglobulin infusions. Both patients developed interstitial pneumonia characterized by fever, cough, and anorexia and associated with elevation of CRP and ferritin, but have never required oxygen ventilation or intensive care. CONCLUSION: Our report suggests that XLA patients might present with high risk to develop pneumonia after SARS-CoV-2 infection, but can recover from infection, suggesting that B-cell response might be important, but is not strictly required to overcome the disease. However, there is a need for larger observational studies to extend these conclusions to other patients with similar genetic immune defects.

positive: Sublingual immunization with recombinant adenovirus encoding SARS-CoV spike protein induces systemic and mucosal immunity without redirection of the virus to the brain BACKGROUND: Sublingual (s.l.) administration of soluble protein antigens, inactivated viruses, or virus-like particles has been shown to induce broad immune responses in mucosal and extra-mucosal tissues. Recombinant replication-defective adenovirus vectors (rADVs) infect mucosa surface and therefore can serve as a mucosal antigen delivery vehicle. In this study we examined whether s.l. immunization with rADV encoding spike protein (S) (rADV-S) of severe acute respiratory syndrome-associated coronavirus (SARS-CoV) induces protective immunity against SARS-CoV and could serve as a safe mucosal route for delivery of rADV. RESULTS: Here, we show that s.l. administration of rADV-S induced serum SARS-CoV neutralizing and airway IgA antibodies in mice. These antibody responses are comparable to those induced by intranasal (i.n.) administration. In addition, s.l. immunization induced antigen-specific CD8(+) T cell responses in the lungs that are superior to those induced by intramuscular immunization. Importantly, unlike i.n. administration, s.l. immunization with rADV did not redirect the rADV vector to the olfactory bulb. CONCLUSION: Our study indicates that s.l. immunization with rADV-S is safe and effective in induction of a broad spectrum of immune responses and presumably protection against infection with SARS-CoV.

positive: The role of immunity in susceptibility to respiratory infection in the aging lung Abstract Respiratory tract infections, particularly pneumonia, are a leading cause of death in persons 65 years or older in both developed and developing countries. Because many attributes of immunity wane with advancing age, the elderly may be more susceptible to respiratory infections, even if they appear to be in good health. A decline in the ability of lymphoid tissues to mount an antigen-specific response (adaptive immunity) to specific microorganisms such as influenza virus or Streptococcus pneumoniae is thought to be an important factor in increasing susceptibility to respiratory tract infection with advancing age. However, abnormalities in innate immunity may also contribute to increased susceptibility to respiratory infections and have been poorly characterized in the elderly. Although changes in immune parameters such as T cell subsets and immunoglobulin concentrations have been observed in respiratory secretions from older healthy individuals compared to younger subjects, the significance of these changes for protective immunity in the lung is unknown. The incidence of pneumonia may be lessened by measures such as optimizing treatment of comorbid conditions, optimizing nutrition, and addressing swallowing disorders. The use of vaccines directed against the influenza virus and S. pneumoniae appears to have made an impact on the degree of morbidity and mortality, and perhaps, the incidence, of community-acquired pneumonia. However, better stimulation of specific immune responses with improved vaccines and more widespread use of these vaccines for protection of elderly individuals are needed.

positive: Long-term and herd immunity against SARS-CoV-2: implications from current and past knowledge Effective herd immunity against SARS-CoV-2 will be determined on many factors: the percentage of the immune population, the length and effectiveness of the immune response and the stability of the viral epitopes. The required percentage of immune individuals has been estimated to be 50–66% of the population which, given the current infection rates, will take long to be achieved. Furthermore, data from SARS-CoV suggest that the duration of immunity may not be sufficiently significant, while the immunity response against SARS-CoV-2 may not be efficiently effective in all patients, as relapses have already been reported. In addition, the development of mutant strains, which has already been documented, can cause the reemergence of the epidemic. In conclusion, the development of an effective vaccine is an urgent necessity, as long-term natural immunity to SARS-CoV-2 may not be sufficient for the control of the current and future outbreaks.

positive: Safety and immunogenicity of a candidate Middle East respiratory syndrome coronavirus viral-vectored vaccine: a dose-escalation, open-label, non-randomised, uncontrolled, phase 1 trial BACKGROUND: Cases of Middle East respiratory syndrome coronavirus (MERS-CoV) infection continue to rise in the Arabian Peninsula 7 years after it was first described in Saudi Arabia. MERS-CoV poses a significant risk to public health security because of an absence of currently available effective countermeasures. We aimed to assess the safety and immunogenicity of the candidate simian adenovirus-vectored vaccine expressing the full-length spike surface glycoprotein, ChAdOx1 MERS, in humans. METHODS: This dose-escalation, open-label, non-randomised, uncontrolled, phase 1 trial was done at the Centre for Clinical Vaccinology and Tropical Medicine (Oxford, UK) and included healthy people aged 18–50 years with negative pre-vaccination tests for HIV antibodies, hepatitis B surface antigen, and hepatitis C antibodies (and a negative urinary pregnancy test for women). Participants received a single intramuscular injection of ChAdOx1 MERS at three different doses: the low-dose group received 5 × 10(9) viral particles, the intermediate-dose group received 2·5 × 10(10) viral particles, and the high-dose group received 5 × 10(10) viral particles. The primary objective was to assess safety and tolerability of ChAdOx1 MERS, measured by the occurrence of solicited, unsolicited, and serious adverse events after vaccination. The secondary objective was to assess the cellular and humoral immunogenicity of ChAdOx1 MERS, measured by interferon-γ-linked enzyme-linked immunospot, ELISA, and virus neutralising assays after vaccination. Participants were followed up for up to 12 months. This study is registered with ClinicalTrials.gov, NCT03399578. FINDINGS: Between March 14 and Aug 15, 2018, 24 participants were enrolled: six were assigned to the low-dose group, nine to the intermediate-dose group, and nine to the high-dose group. All participants were available for follow-up at 6 months, but five (one in the low-dose group, one in the intermediate-dose group, and three in the high-dose group) were lost to follow-up at 12 months. A single dose of ChAdOx1 MERS was safe at doses up to 5 × 10(10) viral particles with no vaccine-related serious adverse events reported by 12 months. One serious adverse event reported was deemed to be not related to ChAdOx1 MERS. 92 (74% [95% CI 66–81]) of 124 solicited adverse events were mild, 31 (25% [18–33]) were moderate, and all were self-limiting. Unsolicited adverse events in the 28 days following vaccination considered to be possibly, probably, or definitely related to ChAdOx1 MERS were predominantly mild in nature and resolved within the follow-up period of 12 months. The proportion of moderate and severe adverse events was significantly higher in the high-dose group than in the intermediate-dose group (relative risk 5·83 [95% CI 2·11–17·42], p<0·0001) Laboratory adverse events considered to be at least possibly related to the study intervention were self-limiting and predominantly mild in severity. A significant increase from baseline in T-cell (p<0·003) and IgG (p<0·0001) responses to the MERS-CoV spike antigen was observed at all doses. Neutralising antibodies against live MERS-CoV were observed in four (44% [95% CI 19–73]) of nine participants in the high-dose group 28 days after vaccination, and 19 (79% [58–93]) of 24 participants had antibodies capable of neutralisation in a pseudotyped virus neutralisation assay. INTERPRETATION: ChAdOx1 MERS was safe and well tolerated at all tested doses. A single dose was able to elicit both humoral and cellular responses against MERS-CoV. The results of this first-in-human clinical trial support clinical development progression into field phase 1b and 2 trials. FUNDING: UK Department of Health and Social Care, using UK Aid funding, managed by the UK National Institute for Health Research.

positive: Passively acquired challenge immunity to enterotropic coronavirus in mice Maternally-derived passive immunity of infant mice to challenge infection with enterotropic coronavirus mouse hepatitis virus strain Y (MHV-Y) was studied. Pups born to both naive and immune dams, but nursed by naive foster dams, were susceptible to infection, while naive or immune pups nursed by immune foster dams were protected. The MHV infectious dose was identical among naive pups inoculated at 1, 2, 3, or 4 weeks of age. Pups nursing immune dams resisted infection when inoculated at 1, 2, or 3 weeks of age. Three week old pups were protected only if they were allowed access to their immune dams. Pups born to MHV immune dams 4 in consecutive litters acquired equal MHV IgG titers in serum and whey and were all protected against challenge infection. Only pups actively ingesting immune whey at the time of or within two hours after virus inoculation were effectively protected. Pups born to dams immunized by oral inoculation with live MHV acquired both MHV-specific IgA and IgG in their whey, while pups born to dams immunized with killed virus acquired only IgG. Both IgA and IgG, but not IgG alone, were required for complete protection.

positive: Antibody responses against SARS-CoV-2 in COVID-19 patients The emerging coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a global pandemic, and brings formidable challenges to public health, society and the economy worldwide. Currently, the antibody responses against SARS-CoV-2 remains largely unknown. We herein estimated the longevity of specific antibodies against SARS-CoV-2, and reported that antibodies waned over substantially in COVID-19 patients after recovery. This article is protected by copyright. All rights reserved.

positive: Evaluating the promise of recombinant transmissible vaccines Transmissible vaccines have the potential to revolutionize infectious disease control by reducing the vaccination effort required to protect a population against a disease. Recent efforts to develop transmissible vaccines focus on recombinant transmissible vaccine designs (RTVs) because they pose reduced risk if intra-host evolution causes the vaccine to revert to its vector form. However, the shared antigenicity of the vaccine and vector may confer vaccine-immunity to hosts infected with the vector, thwarting the ability of the vaccine to spread through the population. We build a mathematical model to test whether a RTV can facilitate disease management in instances where reversion is likely to introduce the vector into the population or when the vector organism is already established in the host population, and the vector and vaccine share perfect cross-immunity. Our results show that a RTV can autonomously eradicate a pathogen, or protect a population from pathogen invasion, when cross-immunity between vaccine and vector is absent. If cross-immunity between vaccine and vector exists, however, our results show that a RTV can substantially reduce the vaccination effort necessary to control or eradicate a pathogen only when continuously augmented with direct manual vaccination. These results demonstrate that estimating the extent of cross-immunity between vector and vaccine is a critical step in RTV design, and that herpesvirus vectors showing facile reinfection and weak cross-immunity are promising.

positive: How did we get here? A short history of COVID‐19 and other coronavirus‐related epidemics The COVID‐19 epidemic was not the first coronavirus epidemic of this century and represents one of the increasing number of zoonoses from wildlife to impact global health. SARS CoV‐2, the virus causing the COVID‐19 epidemic is distinct from, but closely resembles SARS CoV‐1, which was responsible for the severe acute respiratory syndrome (SARS) outbreak in 2002. SARS CoV‐1 and 2 share almost 80% of genetic sequences and use the same host cell receptor to initiate viral infection. However, SARS predominantly affected individuals in close contact with infected animals and health care workers. In contrast, CoV‐2 exhibits robust person to person spread, most likely by means of asymptomatic carriers, which has resulted in greater spread of disease, overall morbidity and mortality, despite its lesser virulence. We review recent coronavirus‐related epidemics and distinguish clinical and molecular features of CoV‐2, the causative agent for COVID‐19, and review the current status of vaccine trials.

positive: SARS-CoV-2 SPIKE PROTEIN: an optimal immunological target for vaccines COVID-19 has rapidly spread all over the world, progressing into a pandemic. This situation has urgently impelled many companies and public research institutes to concentrate their efforts on research for effective therapeutics. Here, we outline the strategies and targets currently adopted in developing a vaccine against SARS-CoV-2. Based on previous evidence and experience with SARS and MERS, the primary focus has been the Spike protein, considered as the ideal target for COVID-19 immunotherapies.

positive: Development of a Western blot assay for detection of antibodies against coronavirus causing severe acute respiratory syndrome. To identify a major antigenic determinant for use in the development of a rapid serological diagnostic test for severe acute respiratory syndrome (SARS) coronavirus infection and to study the immune response during SARS coronavirus infection in humans, we cloned the full length and six truncated fragments of the nucleocapsid gene, expressed them, and purified them as glutathione S-transferase-tagged recombinant proteins. The reactivities of the recombinant proteins to a panel of antibodies containing 33 SARS coronavirus-positive sera and 66 negative sera and to antibodies against other animal coronaviruses were screened. A truncated 195-amino-acid fragment from the C terminus of the nucleocapsid protein (N195) was identified that had a strong ability to detect antibodies against SARS coronavirus. No cross-reaction was found between the N195 protein and antibodies against chicken, pig, and canine coronaviruses. The N195 protein was used to develop a Western blot assay to detect antibodies against SARS coronavirus in 274 clinically blinded samples. The specificity and sensitivity of this test were 98.3 and 90.9%, respectively. The correlation between our Western blotting assay and an immunofluorescence assay (IFA) was also analyzed. The results of our Western blot assay and IFA for the detection of SARS coronavirus-positive sera were the same. Thus, the N195 protein was identified as a suitable protein to be used as an antigen in Western blot and other possible assays for the detection of SARS coronavirus infection.

positive: Immune Response to Viruses: Antibody-Mediated Immunity The notion about immunity to disease arose from the observation that those who recovered from an apparently contagious disease became resistant to a subsequent similar sickness. Much later it was shown that immunity is transferable by serum. The active serum components were identified to be immunoglobulins (Ig's), called antibodies. The enormous diversity of antibodies specific for distinct viruses, pathogens, and many other antigens is explained by clonal selection, whereby specific B-lymphocyte receptors recognize a particular antigen. The selected B-cells are triggered to undergo replication. A process of further cell differentiation and maturation ensues, leading to secretion of antibodies with high binding affinity toward the triggering antigen. Genes coding for the variable regions (involved in antigen binding) of Ig's are inherited as sets of gene fragments joined to form a complete gene in individual B-cells. This process and further hypermutations ensure the synthesis of diverse high affinity antibodies. The antibodies consist of pairs of light (L) and heavy (H) polypeptide chains. Variations in the constant portion of H-chains lead to production of Ig isotypes (IgM, IgA, IgD, IgE, and IgG (further subdivided into IgG1, IgG2, IgG3 and IgG4)), each having distinct effector functions. Host exposure to viruses leads to the production of antibodies with more than one specificity. Only some of these antibodies, recognizing so-called virus neutralization epitopes, diminish or eliminate virus infectivity. Other virus-specific antibodies play auxiliary roles or are ineffective. Sometimes antibodies cause enhancement of viral diseases or play a role in evasion of the immune system. Many antiviral immunoglobulins are being used for short-term pre-exposure prophylaxis or therapy. Long-term protective effects can be accomplished only by antibodies elicited by successful vaccination relying on the phenomenon of immunological memory. T-lymphocytes play a major role in initiating and maintaining immunity against subsequent virus exposure. Antibodies are one of the essential features of antigen triggered adaptive immunity. Initial early defense against viruses is provided by components of innate immunity which evolutionarily precedes adaptive immunity, and remains an essential part of defense against pathogens in humans.

positive: Epidemiology of seasonal coronaviruses: Establishing the context for COVID-19 emergence Public health preparedness for coronavirus disease 2019 (COVID-19) is challenging in the absence of setting-specific epidemiological data. Here we describe the epidemiology of seasonal coronaviruses (sCoVs) and other cocirculating viruses in the West of Scotland, UK. We analyzed routine diagnostic data for >70,000 episodes of respiratory illness tested molecularly for multiple respiratory viruses between 2005 and 2017. Statistical associations with patient age and sex differed between CoV-229E, CoV-OC43 and CoV-NL63. Furthermore, the timing and magnitude of sCoV outbreaks did not occur concurrently and coinfections were not reported. With respect to other cocirculating respiratory viruses, we found evidence of positive, rather than negative, interactions with sCoVs. These findings highlight the importance of considering cocirculating viruses in the differential diagnosis of COVID-19. Further work is needed to establish the occurrence/degree of cross-protective immunity conferred across sCoVs and with COVID-19, as well as the role of viral coinfection in COVID-19 disease severity.

positive: Is global BCG vaccination‐induced trained immunity relevant to the progression of SARS‐CoV‐2 pandemic?

positive: Pathogenic epitopes, heterologous immunity and vaccine design Substantial research has been directed towards the development of a new generation of vaccines that are based on the inclusion of immunogenic epitopes in recombinant vectors. Here we examine the evidence that under certain conditions immunogenic epitopes can do more harm than good and might therefore be considered pathogenic. We suggest that the specific removal of such pathogenic epitopes from vaccines might increase their prophylactic potential, while minimizing the risk of side-effects from vaccine use.

positive: Is Immuno-modulation the Key to COVID-19 Pandemic?

positive: SARS-CoV-2–A Tough Opponent for the Immune System Coronaviruses recently returned with a new one, SARS-CoV-2, related to a potentially severe respiratory disease-called the coronavirus disease (COVID-19). Research shows that the SARS-CoV-2 can be clustered with the Bat SARS-like coronavirus. Bats possess an additional, innate ability for antiviral defense, and, on the other hand, the potential to go hand-in-hand with the virus to generate variability. Besides the high potential of the novel coronavirus in compromising the respiratory system, its rapid transmission and ability to engage many hosts in severe forms of infections or immunopathological complications make it a tough opponent for the immune system. The interactions between SARS-CoV2 and the host immune system result in unleashing tremendous amounts of cytokines, and these cytokines make a storm that would determine the outcome (recovery or death) of the lungs of the patient.

positive: Cross-reactivity of neutralizing antibody and its correlation with circulating T follicular cells in recovered COVID-19 individuals Seroconversion appeared early after COVID-19 onset, and convalescent sera therapy benefit some critical patients. However, neutralizing antibody (nAb) in convalescents is largely unknown. We found that 97.01% (65/67) of COVID-19 convalescents maintained IgG antibodies with high binding and avidity to SARS-CoV-2 spike subunits S1 and S2, and 95.52% (64/67) had neutralization activity against SARS-CoV-2 pesudovirus, one month after discharge (median ID50, 2.75; IQR, 2.34-3.08). Some sera exhibited cross-neutralization against SARS-CoV (76.12%), MERS-CoV (17.91%), or both (10.45%). Interestingly, individuals recovered from severe disease (severe group) had nAbs with binding and neutralization titers higher than non-severe group. Severe group appeared a rapid increase of lymphocytes and a high proportion of circulating CXCR3+ Tfh cells. Interestingly, the later were spike-specific and positively correlated with SARS-CoV-2 nAb titers. All subjects had no autoimmunity. Our findings provide novel insights into nAb responses in COVID-19 convalescents and facilitate treatment and vaccine development for SARS-CoV-2 infection.

positive: Cross-reactive Antibody Response between SARS-CoV-2 and SARS-CoV Infections The World Health Organization has declared the ongoing outbreak of COVID-19, which is caused by a novel coronavirus SARS-CoV-2, a pandemic. There is currently a lack of knowledge about the antibody response elicited from SARS-CoV-2 infection. One major immunological question concerns antigenic differences between SARS-CoV-2 and SARS-CoV. We address this question by analyzing plasma from patients infected by SARS-CoV-2 or SARS-CoV and from infected or immunized mice. Our results show that, although cross-reactivity in antibody binding to the spike protein is common, cross-neutralization of the live viruses may be rare, indicating the presence of a non-neutralizing antibody response to conserved epitopes in the spike. Whether such low or non-neutralizing antibody response leads to antibody-dependent disease enhancement needs to be addressed in the future. Overall, this study not only addresses a fundamental question regarding antigenicity differences between SARS-CoV-2 and SARS-CoV but also has implications for immunogen design and vaccine development.

positive: A mathematical model reveals the influence of population heterogeneity on herd immunity to SARS-CoV-2 Despite various levels of preventive measures, in 2020 many countries have suffered severely from the coronavirus 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. We show that population heterogeneity can significantly impact disease-induced immunity as the proportion infected in groups with the highest contact rates is greater than in groups with low contact rates. We estimate that if R(0) = 2.5 in an age-structured community with mixing rates fitted to social activity then the disease-induced herd immunity level can be around 43%, which is substantially less than the classical herd immunity level of 60% obtained through homogeneous immunization of the population. Our estimates should be interpreted as an illustration of how population heterogeneity affects herd immunity, rather than an exact value or even a best estimate.

positive: Pathophysiology of COVID-19: Why Children Fare Better than Adults? The world is facing Coronavirus Disease-2019 (COVID-19) pandemic, which is causing a large number of deaths and burden on intensive care facilities. It is caused by Severe Acute Respiratory Syndrome coronavirus-2 (SARS-CoV-2) originating in Wuhan, China. It has been seen that fewer children contract COVID-19 and among infected, children have less severe disease. Insights in pathophysiological mechanisms of less severity in children could be important for devising therapeutics for high-risk adults and elderly. Early closing of schools and day-care centers led to less frequent exposure and hence, lower infection rate in children. The expression of primary target receptor for SARS-CoV-2, i.e. angiotensin converting enzyme-2 (ACE-2), decreases with age. ACE-2 has lung protective effects by limiting angiotensin-2 mediated pulmonary capillary leak and inflammation. Severe COVID-19 disease is associated with high and persistent viral loads in adults. Children have strong innate immune response due to trained immunity (secondary to live-vaccines and frequent viral infections), leading to probably early control of infection at the site of entry. Adult patients show suppressed adaptive immunity and dysfunctional over-active innate immune response in severe infections, which is not seen in children. These could be related to immune-senescence in elderly. Excellent regeneration capacity of pediatric alveolar epithelium may be contributing to early recovery from COVID-19. Children, less frequently, have risk factors such as co-morbidities, smoking, and obesity. But young infants and children with pre-existing illnesses could be high risk groups and need careful monitoring. Studies describing immune-pathogenesis in COVID-19 are lacking in children and need urgent attention.

positive: Structural and functional correlates of enhanced antiviral immunity generated by heteroclitic CD8 T cell epitopes. Peptides that bind poorly to MHC class I molecules often elicit low-functional avidity T cell responses. Peptide modification by altering the anchor residue facilitates increased binding affinity and may elicit T cells with increased functional avidity toward the native epitope ("heteroclitic"). This augmented MHC binding is likely to increase the half-life and surface density of the heteroclitic complex, but precisely how this enhanced T cell response occurs in vivo is not known. Furthermore, the ideal heteroclitic epitope will elicit T cell responses that completely cross-react with the native epitope, maximizing protection and minimizing undesirable off-target effects. Such epitopes have been difficult to identify. In this study, using mice infected with a murine coronavirus that encodes epitopes that elicit high (S510, CSLWNGPHL)- and low (S598, RCQIFANI)-functional avidity responses, we show that increased expression of peptide S598 but not S510 generated T cells with enhanced functional avidity. Thus, immune responses can be augmented toward T cell epitopes with low functional avidity by increasing Ag density. We also identified a heteroclitic epitope (RCVIFANI) that elicited a T cell response with nearly complete cross-reactivity with native epitope and demonstrated increased MHC/peptide abundance compared with native S598. Structural and thermal melt analyses indicated that the Q600V substitution enhanced stability of the peptide/MHC complex without greatly altering the antigenic surface, resulting in highly cross-reactive T cell responses. Our data highlight that increased peptide/MHC complex display contributes to heteroclitic epitope efficacy and describe parameters for maximizing immune responses that cross-react with the native epitope.

positive: Convergent antibody responses to SARS-CoV-2 in convalescent individuals During the COVID-19 pandemic, SARS-CoV-2 infected millions of people and claimed hundreds of thousands of lives. Virus entry into cells depends on the receptor binding domain (RBD) of the SARS-CoV-2 spike protein (S). Although there is no vaccine, it is likely that antibodies will be essential for protection. However, little is known about the human antibody response to SARS-CoV-21-5. Here we report on 149 COVID-19 convalescent individuals. Plasmas collected an average of 39 days after the onset of symptoms had variable half-maximal pseudovirus neutralizing titres: less than 1:50 in 33% and below 1:1,000 in 79%, while only 1% showed titres above 1:5,000. Antibody sequencing revealed expanded clones of RBD-specific memory B cells expressing closely related antibodies in different individuals. Despite low plasma titres, antibodies to three distinct epitopes on RBD neutralized at half-maximal inhibitory concentrations (IC50 values) as low as single digit nanograms per millitre. Thus, most convalescent plasmas obtained from individuals who recover from COVID-19 do not contain high levels of neutralizing activity. Nevertheless, rare but recurring RBD-specific antibodies with potent antiviral activity were found in all individuals tested, suggesting that a vaccine designed to elicit such antibodies could be broadly effective.

positive: Editorial overview: Viral immunology: Generating immunity to diverse viral pathogens

positive: In Silico design and characterization of multi-epitopes vaccine for SARS-CoV2 from its spike proteins COVID 19 is disease caused by novel corona virus, SARS-CoV2 originated in China most probably of Bat origin. Till date, no specific vaccine or drug has been discovered to tackle the infections caused by SARS-CoV2. In response to this pandemic, we utilized bioinformatics knowledge to develop efficient vaccine candidate against SARS-CoV2. Designed vaccine was rich in effective BCR and TCR epitopes screened from the sequence of S-protein of SARS-CoV2. Predicted BCR and TCR epitopes were antigenic in nature non-toxic and probably non-allergen. Modelled and refined tertiary structure was predicted as valid for further use. Protein-Protein interaction prediction of TLR2/4 and designed vaccine indicates promising binding. Designed multiepitope vaccine has induced cell mediated and humoral immunity along with increased interferon gamma response. Macrophages and dendritic cells were also found increased over the vaccine exposure. In silico codon optimization and cloning in expression vector indicates that vaccine can be efficiently expressed in E. coli. In conclusion, predicted vaccine is a good antigen, probable no allergen and has potential to induce cellular and humoral immunity.

positive: Preliminary identification of potential vaccine targets for the COVID-19 coronavirus (SARS-CoV-2) based on SARS-CoV immunological studies The beginning of 2020 has seen the emergence of COVID-19 outbreak caused by a novel coronavirus, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). There is an imminent need to better understand this new virus and to develop ways to control its spread. In this study, we sought to gain insights for vaccine design against SARS-CoV-2 by considering the high genetic similarity between SARS-CoV-2 and SARS-CoV, which caused the outbreak in 2003, and leveraging existing immunological studies of SARS-CoV. By screening the experimentally-determined SARS-CoV-derived B cell and T cell epitopes in the immunogenic structural proteins of SARS-CoV, we identified a set of B cell and T cell epitopes derived from the spike (S) and nucleocapsid (N) proteins that map identically to SARS-CoV-2 proteins. As no mutation has been observed in these identified epitopes among the available SARS-CoV-2 sequences (as of 9 February 2020), immune targeting of these epitopes may potentially offer protection against this novel virus. For the T cell epitopes, we performed a population coverage analysis of the associated MHC alleles and proposed a set of epitopes that is estimated to provide broad coverage globally, as well as in China. Our findings provide a screened set of epitopes that can help guide experimental efforts towards the development of vaccines against SARS-CoV-2.

positive: COVID-19, immune system response, hyperinflammation and repurposing antirheumatic drugs In the Wuhan Province of China, in December 2019, the novel coronavirus 2019 (COVID-19) has caused a severe involvement of the lower respiratory tract leading to an acute respiratory syndrome. Subsequently, coronavirus 2 (SARS-CoV-2) provoked a pandemic which is considered a life-threatening disease. The SARS-CoV-2, a family member of betacoronaviruses, possesses single-stranded positive-sense RNA with typical structural proteins, involving the envelope, membrane, nucleocapsid and spike proteins that are responsible for the viral infectivity, and nonstructural proteins. The effectual host immune response including innate and adaptive immunity against SARS-Cov-2 seems crucial to control and resolve the viral infection. However, the severity and outcome of the COVID-19 might be associated with the excessive production of proinflammatory cytokines “cytokine storm” leading to an acute respiratory distress syndrome. Regretfully, the exact pathophysiology and treatment, especially for the severe COVID-19, is still uncertain. The results of preliminary studies have shown that immune-modulatory or immune-suppressive treatments such as hydroxychloroquine, interleukin (IL)-6 and IL-1 antagonists, commonly used in rheumatology, might be considered as treatment choices for COVID-19, particularly in severe disease. In this review, to gain better information about appropriate anti-inflammatory treatments, mostly used in rheumatology for COVID-19, we have focused the attention on the structural features of SARS-CoV-2, the host immune response against SARS-CoV-2 and its association with the cytokine storm.

positive: Cross-reactive neutralization of SARS-CoV-2 by serum antibodies from recovered SARS patients and immunized animals The current COVID-19 pandemic, caused by a novel coronavirus SARS-CoV-2, poses serious threats to public health and social stability, calling for urgent need for vaccines and therapeutics. SARS-CoV-2 is genetically close to SARS-CoV, thus it is important to define the between antigenic cross-reactivity and neutralization. In this study, we firstly analyzed 20 convalescent serum samples collected from SARS-CoV infected individuals during the 2003 SARS outbreak. All patient sera reacted strongly with the S1 subunit and receptor-binding domain (RBD) of SARS-CoV, cross-reacted with the S ectodomain, S1, RBD, and S2 proteins of SARS-CoV-2, and neutralized both SARS-CoV and SARS-CoV-2 S protein-driven infections. Multiple panels of antisera from mice and rabbits immunized with a full-length S and RBD immunogens of SARS-CoV were also characterized, verifying the cross-reactive neutralization against SARS-CoV-2. Interestingly, we found that a palm civet SARS-CoV-derived RBD elicited more potent cross-neutralizing responses in immunized animals than the RBD from a human SARS-CoV strain, informing a strategy to develop a universe vaccine against emerging CoVs. Summary Serum antibodies from SARS-CoV infected patients and immunized animals cross-neutralize SARS-CoV-2 suggests strategies for universe vaccines against emerging CoVs.

positive: A DNA vaccine induces SARS coronavirus neutralization and protective immunity in mice Public health measures have successfully identified and contained outbreaks of the severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV)(1,2,3,4,5), but concerns remain over the possibility of future recurrences. Finding a vaccine for this virus therefore remains a high priority. Here, we show that a DNA vaccine encoding the spike (S) glycoprotein of the SARS-CoV induces T cell and neutralizing antibody responses, as well as protective immunity, in a mouse model. Alternative forms of S were analysed by DNA immunization. These expression vectors induced robust immune responses mediated by CD4 and CD8 cells, as well as significant antibody titres, measured by enzyme-linked immunosorbent assay. Moreover, antibody responses in mice vaccinated with an expression vector encoding a form of S that includes its transmembrane domain elicited neutralizing antibodies. Viral replication was reduced by more than six orders of magnitude in the lungs of mice vaccinated with these S plasmid DNA expression vectors, and protection was mediated by a humoral but not a T-cell-dependent immune mechanism. Gene-based vaccination for the SARS-CoV elicits effective immune responses that generate protective immunity in an animal model. SUPPLEMENTARY INFORMATION: The online version of this article (doi:10.1038/nature02463) contains supplementary material, which is available to authorized users.

positive: The Privacy of T Cell Memory to Viruses T cell responses to viral infections can mediate either protective immunity or damaging immunopathology. Viral infections induce the proliferation of T cells spe cific for viral antigens and cause a loss in the number of T cells with other specificities. In immunologically naïve hosts, viruses will induce T cell responses that, dependent on the MHC, recognize a distinct hierarchy of virus-encoded T cell epitopes. This hierarchy can change if the host has previously encountered another pathogen that elicited amemory pool of T cells specific to a cross-reactive epitope. This heterologous immunity can deviate the normal immune response and result in either beneficial or harmful effects on the host. Each host has a unique T cell repertoire caused by the random DNA rearrangement that created it, so the specific T cells that create the epitope hierarchy differ between individuals. This “private specificity” seems of little signifi-cance in the T cell responseof a naïvehost toinfection, but it is of profoundimportance under conditions of heterologous immunity, where a small subset of a cross-reactive memory pool may expand and dominate a response. Examples are given of how the private specificities of immune responses under conditions of heterologous immunity influence the pathogenesis of murine and human viral infections.

positive: Antibody Dependent Enhancement Due to Original Antigenic Sin and the Development of SARS Human coronavirus (HCoV) is one of the most common causes of respiratory tract infections throughout the world. Two phenomena observed so far in the development of the SARS-CoV-2 pandemic deserve further attention. First, the relative absence of clinical signs of infections in children, second, the early appearance of IgG in certain patients. From the point of view of immune system physiology, such an early rise of specific IgG is expected in secondary immune responses when memory to a cross-reactive antigen is present, usually from an earlier infection with a coronavirus. It is actually typical for the immune system to respond, to what it already knows, a phenomenon that has been observed in many infections with closely related viruses and has been termed “original antigenic sin.” The question then arises whether such cross-reactive antibodies are protective or not against the new virus. The worst scenario would be when such cross-reactive memory antibodies to related coronaviruses would not only be non-protective but even enhance infection and the clinical course. Such a phenomenon of antibody dependent enhancement (ADE) has already been described in several viral infections. Thus, the development of IgG against SARS-CoV-2 in the course of COVID-19 might not be a simple sign of viral clearance and developing protection against the virus. On the contrary, due to cross-reaction to related coronavirus strains from earlier infections, in certain patients IgG might enhance clinical progression due to ADE. The patient's viral history of coronavirus infection might be crucial to the development of the current infection with SARS-CoV-2. Furthermore, it poses a note of caution when treating COVID-19 patients with convalescent sera.

positive: Cross-neutralization of human and palm civet severe acute respiratory syndrome coronaviruses by antibodies targeting the receptor-binding domain of spike protein. The spike (S) protein of severe acute respiratory syndrome coronavirus (SARS-CoV) is considered as a protective Ag for vaccine design. We previously demonstrated that the receptor-binding domain (RBD) of S protein contains multiple conformational epitopes (Conf I-VI) that confer the major target of neutralizing Abs. Here we show that the recombinant RBDs derived from the S protein sequences of Tor2, GD03, and SZ3, the representative strains of human 2002-2003 and 2003-2004 SARS-CoV and palm civet SARS-CoV, respectively, induce in the immunized mice and rabbits high titers of cross-neutralizing Abs against pseudoviruses expressing S proteins of Tor2, GD03, and SZ3. We also demonstrate that the Tor2-RBD induced-Conf I-VI mAbs can potently neutralize both human SARS-CoV strains, Tor2 and GD03. However, only the Conf IV-VI, but not Conf I-III mAbs, neutralize civet SARS-CoV strain SZ3. All these mAbs reacted significantly with each of the three RBD variants (Tor2-RBD, GD03-RBD, and SZ3-RBD) that differ at several amino acids. Regardless, the Conf I-IV and VI epitopes were completely disrupted by single-point mutation of the conserved residues in the RBD (e.g., D429A, R441A, or D454A) and the Conf III epitope was significantly affected by E452A or D463A substitution. Interestingly, the Conf V epitope, which may overlap the receptor-binding motif and induce most potent neutralizing Abs, was conserved in these mutants. These data suggest that the major neutralizing epitopes of SARS-CoV have been apparently maintained during cross-species transmission, and that RBD-based vaccines may induce broad protection against both human and animal SARS-CoV variants.

positive: Longitudinal evaluation and decline of antibody responses in SARS-CoV-2 infection Antibody (Ab) responses to SARS-CoV-2 can be detected in most infected individuals 10-15 days following the onset of COVID-19 symptoms. However, due to the recent emergence of this virus in the human population it is not yet known how long these Ab responses will be maintained or whether they will provide protection from re-infection. Using sequential serum samples collected up to 94 days post onset of symptoms (POS) from 65 RT-qPCR confirmed SARS-CoV-2-infected individuals, we show seroconversion in >95% of cases and neutralizing antibody (nAb) responses when sampled beyond 8 days POS. We demonstrate that the magnitude of the nAb response is dependent upon the disease severity, but this does not affect the kinetics of the nAb response. Declining nAb titres were observed during the follow up period. Whilst some individuals with high peak ID50 (>10,000) maintained titres >1,000 at >60 days POS, some with lower peak ID50 had titres approaching baseline within the follow up period. A similar decline in nAb titres was also observed in a cohort of seropositive healthcare workers from Guy's and St Thomas' Hospitals. We suggest that this transient nAb response is a feature shared by both a SARS-CoV-2 infection that causes low disease severity and the circulating seasonal coronaviruses that are associated with common colds. This study has important implications when considering widespread serological testing, Ab protection against re-infection with SARS-CoV-2 and the durability of vaccine protection.

positive: The trinity of COVID-19: immunity, inflammation and intervention Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the ongoing coronavirus disease 2019 (COVID-19) pandemic. Alongside investigations into the virology of SARS-CoV-2, understanding the fundamental physiological and immunological processes underlying the clinical manifestations of COVID-19 is vital for the identification and rational design of effective therapies. Here, we provide an overview of the pathophysiology of SARS-CoV-2 infection. We describe the interaction of SARS-CoV-2 with the immune system and the subsequent contribution of dysfunctional immune responses to disease progression. From nascent reports describing SARS-CoV-2, we make inferences on the basis of the parallel pathophysiological and immunological features of the other human coronaviruses targeting the lower respiratory tract - severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV). Finally, we highlight the implications of these approaches for potential therapeutic interventions that target viral infection and/or immunoregulation.

positive: SARS-CoV-2-specific T cells without antibodies

positive: Epidemiological Tools that Predict Partial Herd Immunity to SARS Coronavirus 2 The outbreak of SARS coronavirus 2 (SARS-CoV-2), which occurred in Wuhan, China in December 2019, has caused a worldwide pandemic of coronavirus disease 2019 (COVID-19). However, there is a lack of epidemiological tools to guide effective public policy development. Here we present epidemiological evidence that SARS-CoV-2 S type exited Wuhan or other epicenters in China earlier than L type and conferred partial resistance to the virus on infected populations. Analysis of regional disparities in incidence has revealed that a sharp decline in influenza epidemics is a useful surrogate indicator for the undocumented spread of SARS-CoV-2. The biggest concern in the world is knowing when herd immunity has been achieved and scheduling a time to regain the living activities of each country. This study provides a useful tool to guide the development of local policies to contain the virus.

positive: Immunological responses against SARS-coronavirus infection in humans. Since the outbreak of a SARS epidemic last year, significant advances have been made on our understanding of the mechanisms of interaction between the SARS coronavirus (CoV) and the immune system. Strong humoral responses have been found in most patients following SARS-CoV infection, with high titers of neutralizing Abs present in their convalescent sera. The nucleocapsid (N) and spike (S) proteins of SARS-CoV appear to be the dominant antigens recognized by serum Abs. CD4+ T cell responses against the N protein have been observed in SARS patients and an HLA-A2-restricted cytotoxic T lymphocyte epitope in the S protein has been identified. It is likely that the immune responses induced by SARS-CoV infection could also cause pathological damage to the host, especially in the case of proinflammatory cytokines. There is also evidence suggesting that SARS-CoV might be able to directly invade cells of the immune system. Our understanding on the interaction between SARS-CoV, the immune system and local tissues is essential to future diagnosis, control and treatment of this very contagious disease.

positive: Long-Term Persistence of IgG Antibodies in SARS-CoV Infected Healthcare Workers BACKGROUND: The ongoing worldwide outbreak of the 2019-nCoV is markedly similar to the severe acute respiratory syndrome (SARS) outbreak 17 years ago. During the 2002-2003 SARS outbreak, healthcare workers formed a special population of patients. Although virus-specific IgG play important roles in virus neutralization and prevention against future infection, limited information is available regarding the long term persistence of IgG after infection with SARS-like coronavirus. METHODS: A long-term prospective cohort study followed 34 SARS-CoV-infected healthcare workers from a hospital with clustered infected cases during the 2002-2003 SARS outbreak in Guangzhou, China, with a 13-year follow-up. Serum samples were collected annually from 2003-2015. Twenty SARS-CoV-infected and 40 non-infected healthcare workers were enrolled in 2015, and their serum samples were collected. All sera were tested for IgG antibodies with ELISA using whole virus and a recombinant nucleocapsid protein of SARS-CoV, as a diagnostic antigen. RESULTS: Anti SARS-CoV IgG was found to persist for up to 12 years. IgG titers typically peaked in 2004, declining rapidly from 2004-2006, and then continued to decline at a slower rate. IgG titers in SARS-CoV-infected healthcare workers remained at a significantly high level until 2015. Patients treated with corticosteroids at the time of infection were found to have lower IgG titers than those without. CONCLUSIONS: IgG antibodies against SARS-CoV can persist for at least 12 years. The presence of SARS-CoV IgG might provide protection against SARS-CoV and other betacoronavirus. This study provides valuable information regarding humoral immune responses against SARS-CoV and the 2019-nCoV.

positive: The Essential Facts of Wuhan Novel Coronavirus Outbreak in China and Epitope-based Vaccine Designing against COVID-19 Wuhan Novel Coronavirus disease (COVID-19) outbreak has become a global outbreak which has raised the concern of scientific community to design and discover a definitive cure against this deadly virus which has caused deaths of numerous infected people upon infection and spreading. To date, no antiviral therapy or vaccine is available which can effectively combat the infection caused by this virus. This study was conducted to design possible epitope-based subunit vaccines against the SARS-CoV-2 virus using the approaches of reverse vaccinology and immunoinformatics. Upon continual computational experimentation three possible vaccine constructs were designed and one vaccine construct was selected as the best vaccine based on molecular docking study which is supposed to effectively act against SARS-CoV-2. Later, molecular dynamics simulation and in silico codon adaptation experiments were carried out in order to check biological stability and find effective mass production strategy of the selected vaccine. Hopefully, this study will contribute to uphold the present efforts of the researches to secure a definitive treatment against this lethal virus.

positive: Identification of a critical neutralization determinant of severe acute respiratory syndrome (SARS)-associated coronavirus: importance for designing SARS vaccines Abstract The spike (S) protein of severe acute respiratory syndrome-associated coronavirus (SARS-CoV) is not only responsible for receptor binding, but also a major antigenic determinant capable of inducing protective immunity. In this study, we demonstrated that the receptor-binding domain (RBD) of S protein is an important immunogenic site in patients with SARS and rabbits immunized with inactivated SARS-CoV. Serum samples from convalescent SARS patients and immunized rabbits had potent neutralizing activities against infection by pseudovirus expressing SARS-CoV S protein. Depletion of RBD-specific antibodies from patient or rabbit immune sera by immunoadsorption significantly reduced serum-mediated neutralizing activity, while affinity-purified anti-RBD antibodies had relatively higher potency neutralizing infectivity of SARS pseudovirus, indicating that the RBD of S protein is a critical neutralization determinant of SARS-CoV during viral infection and immunization. Two monoclonal antibodies (1A5 and 2C5) targeting at the RBD of S protein were isolated from mice immunized with inactivated SARS-CoV. Both 1A5 and 2C5 possessed potent neutralizing activities, although they directed against distinct conformation-dependant epitopes as shown by ELISA and binding competition assay. We further demonstrated that 2C5, but not 1A5, was able to block binding of the RBD to angiotensin-converting enzyme 2 (ACE2), the functional receptor on targeted cells. These data provide important information for understanding the antigenicity and immunogenicity of SARS-CoV and for designing SARS vaccines.

positive: SARS-CoV and Emergent Coronaviruses: Viral Determinants of Interspecies Transmission Most new emerging viruses are derived from strains circulating in zoonotic reservoirs. Coronaviruses, which had an established potential for cross-species transmission within domesticated animals, suddenly became relevant with the unexpected emergence of the highly pathogenic human SARS-CoV strain from zoonotic reservoirs in 2002. SARS-CoV infected approximately 8000 people worldwide before public health measures halted the epidemic. Supported by robust time-ordered sequence variation, structural biology, well-characterized patient pools, and biological data, the emergence of SARS-CoV represents one of the best studied natural models of viral disease emergence from zoonotic sources. This review article summarizes previous and more recent advances into the molecular and structural characteristics, with particular emphasis on host-receptor interactions, that drove this remarkable virus disease outbreak in human populations.

positive: Expected and Unexpected Effects of Vaccination Vaccination is widely considered to be one of the greatest medical achievements of civilization and one of the top major breakthroughs of humanity.

positive: Severe Acute Respiratory Syndrome Coronavirus 2-Specific Antibody Responses in Coronavirus Disease Patients A new coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has recently emerged to cause a human pandemic. Although molecular diagnostic tests were rapidly developed, serologic assays are still lacking, yet urgently needed. Validated serologic assays are needed for contact tracing, identifying the viral reservoir, and epidemiologic studies. We developed serologic assays for detection of SARS-CoV-2 neutralizing, spike protein-specific, and nucleocapsid-specific antibodies. Using serum samples from patients with PCR-confirmed SARS-CoV-2 infections, other coronaviruses, or other respiratory pathogenic infections, we validated and tested various antigens in different in-house and commercial ELISAs. We demonstrated that most PCR-confirmed SARS-CoV-2-infected persons seroconverted by 2 weeks after disease onset. We found that commercial S1 IgG or IgA ELISAs were of lower specificity, and sensitivity varied between the 2 assays; the IgA ELISA showed higher sensitivity. Overall, the validated assays described can be instrumental for detection of SARS-CoV-2-specific antibodies for diagnostic, seroepidemiologic, and vaccine evaluation studies.

positive: The lethal sex gap: COVID-19 While Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is disrupting lives across the globe for everyone, it has a more devastating impact on the health of older adults, especially that of older men. This pandemic has highlighted the crucial importance of considering an individual’s age and biological sex in the clinic in addition to other confounding diseases (Kuchel, G.A, J Am Geriatr Soc, 67, 203, 2019, Tannenbaum, C., Nature, 575 451-458, 2009) As an interdisciplinary team of scientists in immunology, hematology, genomics, bioinformatics, and geriatrics, we have been studying how age and sex shape the human immune system. Herein we reflect on how our recent findings on the alterations of the immune system in aging might contribute to our current understanding of COVID-19 infection rate and disease risk.

positive: Dendritic Cell-Specific Delivery of Flt3L by Coronavirus Vectors Secures Induction of Therapeutic Antitumor Immunity Efficacy of antitumor vaccination depends to a large extent on antigen targeting to dendritic cells (DCs). Here, we assessed antitumor immunity induced by attenuated coronavirus vectors which exclusively target DCs in vivo and express either lymphocyte- or DC-activating cytokines in combination with a GFP-tagged model antigen. Tracking of in vivo transduced DCs revealed that vectors encoding for Fms-like tyrosine kinase 3 ligand (Flt3L) exhibited a higher capacity to induce DC maturation compared to vectors delivering IL-2 or IL-15. Moreover, Flt3L vectors more efficiently induced tumor-specific CD8(+) T cells, expanded the epitope repertoire, and provided both prophylactic and therapeutic tumor immunity. In contrast, IL-2- or IL-15-encoding vectors showed a substantially lower efficacy in CD8(+) T cell priming and failed to protect the host once tumors had been established. Thus, specific in vivo targeting of DCs with coronavirus vectors in conjunction with appropriate conditioning of the microenvironment through Flt3L represents an efficient strategy for the generation of therapeutic antitumor immunity.

positive: Herd Immunity: Understanding COVID-19 The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its associated disease, COVID-19, has demonstrated the devastating impact of a novel, infectious pathogen on a susceptible population. Here, we explain the basic concepts of herd immunity and discuss its implications in the context of COVID-19.

positive: Chapter 36 SARS Abstract Five years after the first severe acute respiratory syndrome (SARS) outbreak, several candidate SARS-coronavirus (CoV) vaccines are at various stages of preclinical and clinical development. Based on the observation that SARSCoV infection is efficiently controlled upon passive transfer of antibodies directed against the spike (S) protein of SARS-CoV, vaccines containing the S protein have been formulated. Animals immunized with inactivated whole virus vaccines or live-recombinant vaccines expressing the SARS-CoV S protein (e.g., using rabies virus, vesicular stomatitis virus, bovine parainfluenza virus type 3, adenovirus, or attenuated vaccinia virus MVA as a vector), as well as mice immunized with DNA vaccines expressing the S protein gene all developed neutralizing antibodies to SARS-CoV and were protected against SARS-CoV challenge. Although much effort has been focused on developing a SARS vaccine, the commercial viability of such a vaccine for SARS-CoV will ultimately depend on whether the virus re-emerges in the near future. This vaccine should induce highly cross-reactive neutralizing antibodies to protect against newly emerging viruses related to SARS-CoV and protect both the gastrointestinal and respiratory tract in the absence of significant side effects. Given the fact that in the previous outbreak mainly the elderly succumbed to the infection, special attention should be given to vaccines that are able to efficiently protect aged individuals.

positive: T cells found in COVID-19 patients ‘bode well’ for long-term immunity SARS-CoV-2, the virus that causes COVID-19, has been unclear Now, two studies reveal that infected people harbor T cells that target the virus—and may help them recover Both studies also found that some people never infected with SARS-CoV-2 have these cellular defenses, most likely because they were previously infected with other coronaviruses “This is encouraging data,” says virologist Angela Rasmussen of Columbia University Although the studies don’t clarify whether people who clear a SARS-CoV-2 infection can ward off the virus in the future, both identified strong T cell responses to it, which “bodes well for the development of long-term protective immunity,” Rasmussen says The findings could also help researchers create better vaccines

positive: Proteasome activator PA28γ-dependent degradation of coronavirus disease (COVID-19) nucleocapsid protein The nucleocapsid protein is significant in the formation of viral RNA of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), accounting for the largest proportion of viral structural proteins. Here, we report for the first time that the 11S proteasomal activator PA28γ regulates the intracellular abundance of the SARS-CoV-2 N protein (nCoV N). Furthermore, we have identified proteasome activator PA28γ as a nCoV N binding protein by co-immunoprecipitation assay. As a result of their interaction, nCoV N could be degraded by PA28γ-20S in vitro degradation assay. This was also demonstrated by blocking de novo protein synthesis with cycloheximide. The stability of nCoV N in PA28γ-knockout cells was greater than in PA28γ-wildtype cells. Notably, immunofluorescence staining revealed that knockout of the PA28γ gene in cells led to the transport of nCoV N from the nucleus to the cytoplasm. Overexpression of PA28γ enhanced proteolysis of nCoV N compared to that in PA28γ-N151Y cells containing a dominant-negative PA28γ mutation, which reduced this process. These results suggest that PA28γ binding is important in regulating 20S proteasome activity, which in turn regulates levels of the critical nCoV N nucleocapsid protein of SARS-CoV-2, furthering our understanding of the pathogenesis of COVID-19.

positive: Immune Cell Profiling of COVID-19 Patients in the Recovery Stage by Single-Cell Sequencing COVID-19 caused by SARS-CoV-2 has recently affected over 200,000 people and killed more than 8000. Immune system dysregulation such as lymphopenia and inflammatory cytokine storm has been observed in COVID-19 patients, but it remains unclear for the change of key immune cell subsets and their states during COVID-19. Here, we applied single-cell technology to comprehensively characterize transcriptional changes of peripheral blood mononuclear cells in ten patients recovered from COVID-19. Compared with healthy control, COVID-19 induced a unique signature of immune cells in humans, especially in the early recovery stage (ERS). In ERS patients, T cells were decreased remarkably, while monocytes were increased. A detailed analysis of monocytes showed that there was an increased ratio of classical CD14++ monocytes with highly inflammatory genes expression, as well as a greater abundance of CD14++IL1B+ monocytes. For nature killer (NK) cells and T cells, CD4+ T cells were significantly decreased and expressed high level of inflammatory markers, while NK cells were increased. In addition, T cells were highly expanded clone, especially in CD4+ T memory cells and CD8+ T cells. Among B cells, plasma cells were increased remarkably, and naïve B cells were reduced. Our study also identified several novel B cell receptor (BCR) changes (such as IGHV1-8 and IGHV3-7), and confirmed isotypes (IGKV3-11 and IGHV3-21) previously used for virus vaccine development. The strongest pairing frequencies, IGHV3-23+IGHJ4, indicated a monoclonal state associated with SARS-CoV-2 specificity. Furthermore, integrated analysis predicated that IL-1B and M-CSF may be novel candidate target gene for inflammatory storm, and TNFSF13, IL-18 and IL-4 may be benefit for the recovery of COVID-19 patients. Our study provides the first evidence of inflammatory immune signature in early recovery stage, suggesting that the COVID-19 patients are still vulnerable after hospital discharge. Our identification of novel BCR signaling may lead to the development of vaccine and antibodies for the treatment of COVID-19.

positive: An efficient method to make human monoclonal antibodies from memory B cells: potent neutralization of SARS coronavirus Passive serotherapy can confer immediate protection against microbial infection, but methods to rapidly generate human neutralizing monoclonal antibodies are not yet available. We have developed an improved method for Epstein-Barr virus transformation of human B cells. We used this method to analyze the memory repertoire of a patient who recovered from severe acute respiratory syndrome coronavirus (SARS-CoV) infection and to isolate monoclonal antibodies specific for different viral proteins, including 35 antibodies with in vitro neutralizing activity ranging from 10(−8)M to 10(−11)M. One such antibody confers protection in vivo in a mouse model of SARS-CoV infection. These results show that it is possible to interrogate the memory repertoire of immune donors to rapidly and efficiently isolate neutralizing antibodies that have been selected in the course of natural infection. SUPPLEMENTARY INFORMATION: The online version of this article (doi:10.1038/nm1080) contains supplementary material, which is available to authorized users.

positive: Biological sex impacts COVID-19 outcomes The current novel coronavirus disease 2019 (COVID-19) pandemic is revealing profound differences between men and women in disease outcomes worldwide. In the United States, there has been inconsistent reporting and analyses of male–female differences in COVID-19 cases, hospitalizations, and deaths. We seek to raise awareness about the male-biased severe outcomes from COVID-19, highlighting the mechanistic differences including in the expression and activity of angiotensin-converting enzyme 2 (ACE2) as well as in antiviral immunity. We also highlight how sex differences in comorbidities, which can be associated with both age and race, impact male-biased outcomes from COVID-19.

positive: Lack of cross-neutralization by SARS patient sera towards SARS-CoV-2 Despite initial findings indicating that SARS-CoV and SARS-CoV-2 are genetically related belonging to the same virus species and that the two viruses used the same entry receptor, angiotensin-converting enzyme 2 (ACE2), our data demonstrated that there is no detectable cross-neutralization by SARS patient sera against SARS-CoV-2. We also found that there are significant levels of neutralizing antibodies in recovered SARS patients 9–17 years after initial infection. These findings will be of significant use in guiding the development of serologic tests, formulating convalescent plasma therapy strategies, and assessing the longevity of protective immunity for SARS-related coronaviruses in general as well as vaccine efficacy.

positive: Role of serology in the COVID-19 pandemic

positive: Serological assays for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), March 2020 BACKGROUND: The ongoing coronavirus disease (COVID-19) pandemic has major impacts on health systems, the economy and society. Assessing infection attack rates in the population is critical for estimating disease severity and herd immunity which is needed to calibrate public health interventions. We have previously shown that it is possible to achieve this in real time to impact public health decision making. AIM: Our objective was to develop and evaluate serological assays applicable in large-scale sero-epidemiological studies. METHODS: We developed an ELISA to detect IgG and IgM antibodies to the receptor-binding domain (RBD) of the spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We evaluated its sensitivity and specificity in combination with confirmatory microneutralisation (MN) and 90% plaque reduction neutralisation tests (PRNT(90)) in 51 sera from 24 patients with virologically confirmed COVID-19 and in age-stratified sera from 200 healthy controls. RESULTS: IgG and IgM RBD ELISA, MN and PRNT(90) were reliably positive after 29 days from illness onset with no detectable cross-reactivity in age-stratified controls. We found that PRNT(90) tests were more sensitive in detecting antibody than MN tests carried out with the conventional 100 tissue culture infectious dose challenge. Heparinised plasma appeared to reduce the infectivity of the virus challenge dose and may confound interpretation of neutralisation test. CONCLUSION: Using IgG ELISA based on the RBD of the spike protein to screen sera for SARS-CoV-2 antibody, followed by confirmation using PRNT(90), is a valid approach for large-scale sero-epidemiology studies.

positive: Distinct systems serology features in children, elderly and COVID patients SARS-CoV-2, the pandemic coronavirus that causes COVID-19, has infected millions worldwide, causing unparalleled social and economic disruptions. COVID-19 results in higher pathogenicity and mortality in the elderly compared to children. Examining baseline SARS-CoV-2 cross-reactive coronavirus immunological responses, induced by circulating human coronaviruses, is critical to understand such divergent clinical outcomes. The cross-reactivity of coronavirus antibody responses of healthy children (n=89), adults (n=98), elderly (n=57), and COVID-19 patients (n=19) were analysed by systems serology. While moderate levels of cross-reactive SARS-CoV-2 IgG, IgM, and IgA were detected in healthy individuals, we identified serological signatures associated with SARS-CoV-2 antigen-specific Fc{gamma} receptor binding, which accurately distinguished COVID-19 patients from healthy individuals and suggested that SARS-CoV-2 induces qualitative changes to antibody Fc upon infection, enhancing Fc{gamma} receptor engagement. Vastly different serological signatures were observed between healthy children and elderly, with markedly higher cross-reactive SARS-CoV-2 IgA and IgG observed in elderly, whereas children displayed elevated SARS-CoV-2 IgM, including receptor binding domain-specific IgM with higher avidity. These results suggest that less-experienced humoral immunity associated with higher IgM, as observed in children, may have the potential to induce more potent antibodies upon SARS-CoV-2 infection. These key insights will inform COVID-19 vaccination strategies, improved serological diagnostics and therapeutics.

positive: COVID-19 and Individual Genetic Susceptibility/Receptivity: Role of ACE1/ACE2 Genes, Immunity, Inflammation and Coagulation. Might the Double X-Chromosome in Females Be Protective against SARS-CoV-2 Compared to the Single X-Chromosome in Males? In December 2019, a novel severe acute respiratory syndrome (SARS) from a new coronavirus (SARS-CoV-2) was recognized in the city of Wuhan, China. Rapidly, it became an epidemic in China and has now spread throughout the world reaching pandemic proportions. High mortality rates characterize SARS-CoV-2 disease (COVID-19), which mainly affects the elderly, causing unrestrained cytokines-storm and subsequent pulmonary shutdown, also suspected micro thromboembolism events. At the present time, no specific and dedicated treatments, nor approved vaccines, are available, though very promising data come from the use of anti-inflammatory, anti-malaria, and anti-coagulant drugs. In addition, it seems that males are more susceptible to SARS-CoV-2 than females, with males 65% more likely to die from the infection than females. Data from the World Health Organization (WHO) and Chinese scientists show that of all cases about 1.7% of women who contract the virus will die compared with 2.8% of men, and data from Hong Kong hospitals state that 32% of male and 15% of female COVID-19 patients required intensive care or died. On the other hand, the long-term fallout of coronavirus may be worse for women than for men due to social and psychosocial reasons. Regardless of sex- or gender-biased data obtained from WHO and those gathered from sometimes controversial scientific journals, some central points should be considered. Firstly, SARS-CoV-2 has a strong interaction with the human ACE2 receptor, which plays an essential role in cell entry together with transmembrane serine protease 2 (TMPRSS2); it is interesting to note that the ACE2 gene lays on the X-chromosome, thus allowing females to be potentially heterozygous and differently assorted compared to men who are definitely hemizygous. Secondly, the higher ACE2 expression rate in females, though controversial, might ascribe them the worst prognosis, in contrast with worldwide epidemiological data. Finally, several genes involved in inflammation are located on the X-chromosome, which also contains high number of immune-related genes responsible for innate and adaptive immune responses to infection. Other genes, out from the RAS-pathway, might directly or indirectly impact on the ACE1/ACE2 balance by influencing its main actors (e.g., ABO locus, SRY, SOX3, ADAM17). Unexpectedly, the higher levels of ACE2 or ACE1/ACE2 rebalancing might improve the outcome of COVID-19 in both sexes by reducing inflammation, thrombosis, and death. Moreover, X-heterozygous females might also activate a mosaic advantage and show more pronounced sex-related differences resulting in a sex dimorphism, further favoring them in counteracting the progression of the SARS-CoV-2 infection.

positive: Candidate targets for immune responses to 2019-Novel Coronavirus (nCoV): sequence homology- and bioinformatic-based predictions Effective countermeasures against the recent emergence and rapid expansion of the 2019-Novel Coronavirus (2019-nCoV) require the development of data and tools to understand and monitor viral spread and immune responses. However, little information about the targets of immune responses to 2019-nCoV is available. We used the Immune Epitope Database and Analysis Resource (IEDB) resource to catalog available data related to other coronaviruses, including SARS-CoV, which has high sequence similarity to 2019-nCoV, and is the best-characterized coronavirus in terms of epitope responses. We identified multiple specific regions in 2019-nCoV that have high homology to SARS virus. Parallel bionformatic predictions identified a priori potential B and T cell epitopes for 2019-nCoV. The independent identification of the same regions using two approaches reflects the high probability that these regions are targets for immune recognition of 2019-nCoV. ONE SENTENCE SUMMARY We identified potential targets for immune responses to 2019-nCoV and provide essential information for understanding human immune responses to this virus and evaluation of diagnostic and vaccine candidates.

positive: Toll-Like Receptor 3 Signaling via TRIF Contributes to a Protective Innate Immune Response to Severe Acute Respiratory Syndrome Coronavirus Infection Toll-like receptors (TLRs) are sensors that recognize molecular patterns from viruses, bacteria, and fungi to initiate innate immune responses to invading pathogens. The emergence of highly pathogenic coronaviruses severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV) is a concern for global public health, as there is a lack of efficacious vaccine platforms and antiviral therapeutic strategies. Previously, it was shown that MyD88, an adaptor protein necessary for signaling by multiple TLRs, is a required component of the innate immune response to mouse-adapted SARS-CoV infection in vivo. Here, we demonstrate that TLR3(−/−), TLR4(−/−), and TRAM(−/−) mice are more susceptible to SARS-CoV than wild-type mice but experience only transient weight loss with no mortality in response to infection. In contrast, mice deficient in the TLR3/TLR4 adaptor TRIF are highly susceptible to SARS-CoV infection, showing increased weight loss, mortality, reduced lung function, increased lung pathology, and higher viral titers. Distinct alterations in inflammation were present in TRIF(−/−) mice infected with SARS-CoV, including excess infiltration of neutrophils and inflammatory cell types that correlate with increased pathology of other known causes of acute respiratory distress syndrome (ARDS), including influenza virus infections. Aberrant proinflammatory cytokine, chemokine, and interferon-stimulated gene (ISG) signaling programs were also noted following infection of TRIF(−/−) mice that were similar to those seen in human patients with poor disease outcome following SARS-CoV or MERS-CoV infection. These findings highlight the importance of TLR adaptor signaling in generating a balanced protective innate immune response to highly pathogenic coronavirus infections.

positive: Pathways to COVID-19 ‘community protection’

positive: Antibody Profiling and Prevalence in the US population during the SARS-CoV2 Pandemic ABSTRACT Background: Antibody diagnostics play an important role in disease detection and can potentially aid in monitoring of the immune responses to see if an individual has developed immunity. Developing high throughput diagnostics which does not involve handling of infectious material becomes imperative in the case of pandemics such as the recent outbreak of SARS-CoV2. Methods: A protein microarray technology was used to detect the plurality of antibody response to four novel antigens namely S1 glycoprotein, Receptor binding domain (RBD), S2 glycoprotein and Nucleoprotein of the novel coronavirus named SARS-CoV2 using serum samples. A DBS card was additionally used to compare its performance with a venipuncture-based serum separator tube (SST) draw. Results: The three main subclasses of antibodies IgM, IgA and IgG were analyzed to see the variations in immune responses in the affected population and compared to their microbial RT-PCR based NP swab results. The clinical sensitivity and specificity were determined to be 98.1% and 98.6%. In the matrix comparison study, which would enable patients to test without risk of transmitting the virus, DBS matched with higher than 98% accuracy to a venipuncture-based SST collection. Conclusion: Multiplex testing enables higher sensitivity and specificity which is essential while establishing exposure on a population scale. This flexible platform along with a discrete collection methodology would be crucial and broadly useful to scale up testing in current and future pandemics. Minimum sample volume that can be collected using DBS cards can be processed in this multiplex pillar plate format enabling the capacity to provide the reliability of high throughput analyzers while having the ease of collection similar to rapid tests. Keywords: COVID19, SARS-CoV2, Antibody, Multiplex, serology, biomarker, immune modulation, prevalence, high sensitivity, high specificity, Dried blood spot, pandemic, venipuncture

positive: Testing for SARS-CoV-2 (COVID-19): a systematic review and clinical guide to molecular and serological in-vitro diagnostic assays The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its associated Coronavirus disease 2019 (COVID-19) pandemic has demanded rapid upscaling of in-vitro diagnostic assays to enable mass screening and testing of high-risk groups, and simultaneous ascertainment of robust data on past SARS-CoV-2 exposure at an individual and population level. To meet the exponential demand in testing, there has been an accelerated development of both molecular and serological assays across a plethora of platforms. In the present review, we discuss the current literature on these modalities including the nucleic acid amplification tests, direct viral antigen tests and the rapidly expanding laboratory based and point of care serological tests. This suite of complementary tests will inform crucial decisions by healthcare providers and policy makers and understanding their strengths and limitations will be critical to their judicious application for the development of algorithmic approaches to treatment and public health strategies.

positive: Human Monoclonal Antibody Combination against SARS Coronavirus: Synergy and Coverage of Escape Mutants BACKGROUND: Experimental animal data show that protection against severe acute respiratory syndrome coronavirus (SARS-CoV) infection with human monoclonal antibodies (mAbs) is feasible. For an effective immune prophylaxis in humans, broad coverage of different strains of SARS-CoV and control of potential neutralization escape variants will be required. Combinations of virus-neutralizing, noncompeting mAbs may have these properties. METHODS AND FINDINGS: Human mAb CR3014 has been shown to completely prevent lung pathology and abolish pharyngeal shedding of SARS-CoV in infected ferrets. We generated in vitro SARS-CoV variants escaping neutralization by CR3014, which all had a single P462L mutation in the glycoprotein spike (S) of the escape virus. In vitro experiments confirmed that binding of CR3014 to a recombinant S fragment (amino acid residues 318–510) harboring this mutation was abolished. We therefore screened an antibody-phage library derived from blood of a convalescent SARS patient for antibodies complementary to CR3014. A novel mAb, CR3022, was identified that neutralized CR3014 escape viruses, did not compete with CR3014 for binding to recombinant S1 fragments, and bound to S1 fragments derived from the civet cat SARS-CoV-like strain SZ3. No escape variants could be generated with CR3022. The mixture of both mAbs showed neutralization of SARS-CoV in a synergistic fashion by recognizing different epitopes on the receptor-binding domain. Dose reduction indices of 4.5 and 20.5 were observed for CR3014 and CR3022, respectively, at 100% neutralization. Because enhancement of SARS-CoV infection by subneutralizing antibody concentrations is of concern, we show here that anti-SARS-CoV antibodies do not convert the abortive infection of primary human macrophages by SARS-CoV into a productive one. CONCLUSIONS: The combination of two noncompeting human mAbs CR3014 and CR3022 potentially controls immune escape and extends the breadth of protection. At the same time, synergy between CR3014 and CR3022 may allow for a lower total antibody dose to be administered for passive immune prophylaxis of SARS-CoV infection.

positive: COVIDep platform for real-time reporting of vaccine target recommendations for SARS-CoV-2: Description and connections with COVID-19 immune responses and preclinical vaccine trials We introduce COVIDep (https://COVIDep.ust.hk), a web-based platform that provides immune target recommendations for guiding SARS-CoV-2 vaccine development. COVIDep implements a protocol that pools together publicly-available genetic data for SARS-CoV-2 and epitope data for SARS-CoV to identify B cell and T cell epitopes that present potential immune targets for SARS-CoV-2. Correspondences between outputs of COVIDep and immune responses recorded in COVID-19 patients and preclinical vaccine trials are also indicated. The platform is user-friendly, flexible, and based on up-to-date data. It may help guide vaccine designs and associated experimental studies for SARS-CoV-2.

positive: Human Leukocyte Antigen Susceptibility Map for Severe Acute Respiratory Syndrome Coronavirus 2 Genetic variability across the three major histocompatibility complex (MHC) class I genes (human leukocyte antigen A [HLA-A], -B, and -C genes) may affect susceptibility to and severity of the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus responsible for coronavirus disease 2019 (COVID-19). We performed a comprehensive in silico analysis of viral peptide-MHC class I binding affinity across 145 HLA-A, -B, and -C genotypes for all SARS-CoV-2 peptides. We further explored the potential for cross-protective immunity conferred by prior exposure to four common human coronaviruses. The SARS-CoV-2 proteome was successfully sampled and was represented by a diversity of HLA alleles. However, we found that HLA-B*46:01 had the fewest predicted binding peptides for SARS-CoV-2, suggesting that individuals with this allele may be particularly vulnerable to COVID-19, as they were previously shown to be for SARS (M. Lin, H.-T. Tseng, J. A. Trejaut, H.-L. Lee, et al., BMC Med Genet 4:9, 2003, https://bmcmedgenet.biomedcentral.com/articles/10.1186/1471-2350-4-9). Conversely, we found that HLA-B*15:03 showed the greatest capacity to present highly conserved SARS-CoV-2 peptides that are shared among common human coronaviruses, suggesting that it could enable cross-protective T-cell-based immunity. Finally, we reported global distributions of HLA types with potential epidemiological ramifications in the setting of the current pandemic.IMPORTANCE Individual genetic variation may help to explain different immune responses to a virus across a population. In particular, understanding how variation in HLA may affect the course of COVID-19 could help identify individuals at higher risk from the disease. HLA typing can be fast and inexpensive. Pairing HLA typing with COVID-19 testing where feasible could improve assessment of severity of viral disease in the population. Following the development of a vaccine against SARS-CoV-2, the virus that causes COVID-19, individuals with high-risk HLA types could be prioritized for vaccination.

positive: Anti-SARS-CoV-2 hyperimmune plasma workflow Coronavirus disease 2019 (COVID-19) caused by the novel coronavirus has become a Public Health Emergency of International Concern. Among the various treatment proposals for COVID-19 infection, passive immunotherapy using plasma from recovering patients - "convalescent plasma" (CP )- could be a promising option in the treatment of SARS-CoV-2 infections. Immune (i.e. "convalescent") plasma refers to plasma that is collected from individuals, following resolution of infection and development of antibodies. Passive antibody administration through transfusion of convalescent plasma may offer the only short-term strategy to confer immediate immunity to susceptible individuals. According to the World Health Organization (WHO), the use of plasma therapy is permitted when faced with «serious diseases for which there are no effective pharmacological treatments». Several clinical trials are underway to test the effectiveness of hyperimmune plasma at various stages of SARS-CoV2.The Food and Drug Administration (FDA), the U.S. regulatory authority, has approved the use of CP for compassionate use in the treatment of patients with a critical COVID-19 infection. Below are the general indications for drawing up clinical protocols for the integral management of "COVID-19-convalescent plasma" for which the validation and approval of the Ethics Committees is still necessary.

positive: A Sequence Homology and Bioinformatic Approach Can Predict Candidate Targets for Immune Responses to SARS-CoV-2 Effective countermeasures against the recent emergence and rapid expansion of the 2019 novel coronavirus (SARS-CoV-2) require the development of data and tools to understand and monitor its spread and immune responses to it. However, little information is available about the targets of immune responses to SARS-CoV-2. We used the Immune Epitope Database and Analysis Resource (IEDB) to catalog available data related to other coronaviruses. This includes SARS-CoV, which has high sequence similarity to SARS-CoV-2 and is the best-characterized coronavirus in terms of epitope responses. We identified multiple specific regions in SARS-CoV-2 that have high homology to the SARS-CoV virus. Parallel bioinformatic predictions identified a priori potential B and T cell epitopes for SARS-CoV-2. The independent identification of the same regions using two approaches reflects the high probability that these regions are promising targets for immune recognition of SARS-CoV-2. These predictions can facilitate effective vaccine design against this virus of high priority.

positive: Immunity and age: living in the past? Increasing age is associated with a decreasing ability to mediate effective immune responses to newly encountered antigens. It is generally believed that this reflects the age-associated decline in the number, repertoire and function of available naive T cells. Here, we propose that naive T cells become increasingly irrelevant to the immune system, and that responses to newly encountered antigens are progressively dominated by cross-reactive memory T cells as the individual ages. In addition, we propose that the majority, if not all, of the response to newly encountered antigens in the elderly is mediated by cross-reactive memory T cells. This predicts highly stochastic responses to new infections that should vary between individuals, and has important implications for vaccination strategies in the elderly.

positive: Current Scenario of COVID-19 in Pediatric Age Group and Physiology of Immune and Thymus response Abstract COVID-19 pandemic caused by SARS-CoV-2, continues to manifest with severe acute respiratory syndrome among the adults, however, it offers a convincing indication of less severity and fatality in pediatric age group (0-18 years). The current trend suggests that children may get infected but are less symptomatic with less fatality, which is concordant to earlier epidemic outbreaks of SARS-CoV and MERS-CoV, in 2002 and 2012, respectively. According to the available data, children appear to be at lower risk for COVID-19, as adults constitute for maximum number of the confirmed cases (308,592) and deaths (13,069) as on 22nd March ( https://www.worldometers.info/coronavirus ). However, rapid publications and information of the adult patients with COVID-19 is in progress and published, on the contrary, almost no comprehensive data or discussion about the COVID-19 in children is available. Therefore, in this review, we outline the epidemiology, clinical symptoms, diagnosis, treatment, prevention, possible immune response and role of thymus in children to combat the COVID-19 outbreak.

positive: Severe acute respiratory syndrome vaccine development: experiences of vaccination against avian infectious bronchitis coronavirus. Vaccines against infectious bronchitis of chickens (Gallus gallus domesticus) have arguably been the most successful, and certainly the most widely used, of vaccines for diseases caused by coronaviruses, the others being against bovine, canine, feline and porcine coronaviruses. Infectious bronchitis virus (IBV), together with the genetically related coronaviruses of turkey (Meleagris gallopovo) and ring-necked pheasant (Phasianus colchicus), is a group 3 coronavirus, severe acute respiratory syndrome (SARS) coronavirus being tentatively in group 4, the other known mammalian coronaviruses being in groups 1 and 2. IBV replicates not only in respiratory tissues (including the nose, trachea, lungs and airsacs, causing respiratory disease), but also in the kidney (associated with minor or major nephritis), oviduct, and in many parts of the alimentary tract--the oesophagus, proventriculus, duodenum, jejunum, bursa of Fabricius, caecal tonsils (near the distal end of the tract), rectum and cloaca (the common opening for release of eggs and faeces), usually without clinical effects. The virus can persist, being re-excreted at the onset of egg laying (4 to 5 months of age), believed to be a consequence of the stress of coming into lay. Genetic lines of chickens differ in the extent to which IBV causes mortality in chicks, and in respect of clearance of the virus after the acute phase. Live attenuated (by passage in chicken embryonated eggs) IBV strains were introduced as vaccines in the 1950s, followed a couple of decades later by inactivated vaccines for boosting protection in egg-laying birds. Live vaccines are usually applied to meat-type chickens at 1 day of age. In experimental situations this can result in sterile immunity when challenged by virulent homologous virus. Although 100% of chickens may be protected (against clinical signs and loss of ciliary activity in trachea), sometimes 10% of vaccinated chicks do not respond with a protective immune response. Protection is short lived, the start of the decline being apparent 9 weeks after vaccination with vaccines based on highly attenuated strains. IBV exists as scores of serotypes (defined by the neutralization test), cross-protection often being poor. Consequently, chickens may be re-vaccinated, with the same or another serotype, two or three weeks later. Single applications of inactivated virus has generally led to protection of <50% of chickens. Two applications have led to 90 to 100% protection in some reports, but remaining below 50% in others. In practice in the field, inactivated vaccines are used in laying birds that have previously been primed with two or three live attenuated virus vaccinations. This increases protection of the laying birds against egg production losses and induces a sustained level of serum antibody, which is passed to progeny. The large spike glycoprotein (S) comprises a carboxy-terminal S2 subunit (approximately 625 amino acid residues), which anchors S in the virus envelope, and an amino-terminal S1 subunit (approximately 520 residues), believed to largely form the distal bulbous part of S. The S1 subunit (purified from IBV virus, expressed using baculovirus or expressed in birds from a fowlpoxvirus vector) induced virus neutralizing antibody. Although protective immune responses were induced, multiple inoculations were required and the percentage of protected chickens was too low (<50%) for commercial application. Remarkably, expression of S1 in birds using a non-pathogenic fowl adenovirus vector induced protection in 90% and 100% of chickens in two experiments. Differences of as little as 5% between the S1 sequences can result in poor cross-protection. Differences in S1 of 2 to 3% (10 to 15 amino acids) can change serotype, suggesting that a small number of epitopes are immunodominant with respect to neutralizing antibody. Initial studies of the role of the IBV nucleocapsid protein (N) in immunity suggested that immunization with bacterially expressed N, while not inducing protection directly, improved the induction of protection by a subsequent inoculation with inactivated IBV. In another study, two intramuscular immunizations of a plasmid expressing N induced protective immunity. The basis of immunity to IBV is not well understood. Serum antibody levels do not correlate with protection, although local antibody is believed to play a role. Adoptive transfer of IBV-infection-induced alphabeta T cells bearing CD8 antigen protected chicks from challenge infection. In conclusion, live attenuated IBV vaccines induce good, although short-lived, protection against homologous challenge, although a minority of individuals may respond poorly. Inactivated IBV vaccines are insufficiently efficacious when applied only once and in the absence of priming by live vaccine. Two applications of inactivated IBV are much more efficacious, although this is not a commercially viable proposition in the poultry industry. However, the cost and logistics of multiple application of a SARS inactivated vaccine would be more acceptable for the protection of human populations, especially if limited to targeted groups (e.g. health care workers and high-risk contacts). Application of a SARS vaccine is perhaps best limited to a minimal number of targeted individuals who can be monitored, as some vaccinated persons might, if infected by SARS coronavirus, become asymptomatic excretors of virus, thereby posing a risk to non-vaccinated people. Looking further into the future, the high efficacy of the fowl adenovirus vector expressing the IBV S1 subunit provides optimism for a live SARS vaccine, if that were deemed to be necessary, with the possibility of including the N protein gene.

positive: SARS-CoV-2 specific antibody responses in COVID-19 patients A new coronavirus, SARS-CoV-2, has recently emerged to cause a human pandemic. Whereas molecular diagnostic tests were rapidly developed, serologic assays are still lacking, yet urgently needed. Validated serologic assays are important for contact tracing, identifying the viral reservoir and epidemiological studies. Here, we developed serological assays for the detection of SARS-CoV-2 neutralizing, spike- and nucleocapsid-specific antibodies. Using serum samples from patients with PCR-confirmed infections of SARS-CoV-2, other coronaviruses, or other respiratory pathogenic infections, we validated and tested various antigens in different in-house and commercial ELISAs. We demonstrate that most PCR-confirmed SARS-CoV-2 infected individuals seroconverted, as revealed by sensitive and specific in-house ELISAs. We found that commercial S1 IgG or IgA ELISAs were of lower specificity while sensitivity varied between the two, with IgA showing higher sensitivity. Overall, the validated assays described here can be instrumental for the detection of SARS-CoV-2-specific antibodies for diagnostic, seroepidemiological and vaccine evaluation studies.

positive: Production of specific antibodies against SARS-coronavirus nucleocapsid protein without cross reactivity with human coronaviruses 229E and OC43 Severe acute respiratory syndrome (SARS) is a life-threatening disease for which accurate diagnosis is essential. Although many tools have been developed for the diagnosis of SARS, false-positive reactions in negative sera may occur because of cross-reactivity with other coronaviruses. We have raised polyclonal and monoclonal antibodies (Abs) using a recombinant form of the SARS virus nucleocapsid protein. Cross-reactivity of these anti-SARS Abs against human coronavirus (HCoV) 229E and HCoV OC43 were determined by Western blotting. The Abs produced reacted with recombinant SARS virus nucleocapsid protein, but not with HCoV 229E or HCoV OC43.

positive: Do COVID-19 and SARS Gene Complexities and Variations Help Overcome the Knowledge Gap? A whole new pathogen, to which humans have virtually no pre-existing immunity, has caused fear all over the world. Severe acute respiratory syndrome coronavirus (SARS CoV-2) is one of the types of human novel-coronavirus of the family coronavirus. The nature of transmission of the virus makes it one of the most infectious pathogenic diseases that has ever existed. Though the human coronaviruses have existed since the discovery of the human coronavirus 229E (HCoV-229E) and human coronavirus OC43 (HCoV-OC43) in 1960, it has been a challenge to develop an effective cure as well as vaccine for the diseases associated with coronaviruses. Commonly, human coronaviruses cause illnesses such as intestinal and respiratory tract illnesses. Nevertheless, the symptoms reflected after infection from the coronaviruses take some time before being identified. Thus, viruses can replicate and cause more harm to the human body before being detected. Moreover, research continues to explain why some gene variations in some individuals increase the risk of some infectious diseases, while others are not affected. Looking at gene variations in people infected with Coronavirus Disease 2019 (COVID-19) and studying how genes influence people's response to infection will help to develop a vaccine that will help strengthen the immune system. Knowing how the human genes respond to the virus COVID-19 will help to cure people more effectively.

positive: CCL28 chemokine: An anchoring point bridging innate and adaptive immunity Abstract Chemokines are an extensive family of small proteins which, in conjunction with their receptors, guide the chemotactic activity of various immune cells throughout the body. CCL28, β- or CC chemokine, is involved in the host immunity at various epithelial and mucosal linings. The unique roles of CCL28 in several facets of immune responses have attracted considerable attention and may represent a promising approach to combat various infections. CCL28 displays a broad spectrum of antimicrobial activity against gram-negative and gram-positive bacteria, as well as fungi. Here, we will summarize various research findings regarding the antimicrobial activity of CCL28 and the relevant mechanisms behind it. We will explore how the structure of CCL28 is involved with this activity and how this function may have evolved. CCL28 displays strong homing capabilities for B and T cells at several mucosal and epithelial sites, and orchestrates the trafficking and functioning of lymphocytes. The chemotactic and immunomodulatory features of CCL28 through the interactions with its chemokine receptors, CCR10 and CCR3, will also be discussed in detail. Thus, in this review, we emphasize the dual properties of CCL28 and suggest its role as an anchoring point bridging the innate and adaptive immunity.

positive: Harnessing the natural anti-glycan immune response to limit the transmission of enveloped viruses such as SARS-CoV-2

positive: Comprehensive Transcriptomic Analysis of COVID-19 Blood, Lung, and Airway Abstract SARS-CoV2 is a previously uncharacterized coronavirus and causative agent of the COVID-19 pandemic. The host response to SARS-CoV2 has not yet been fully delineated, hampering a precise approach to therapy. To address this, we carried out a comprehensive analysis of gene expression data from the blood, lung, and airway of COVID-19 patients. Our results indicate that COVID-19 pathogenesis is driven by populations of myeloid-lineage cells with highly inflammatory but distinct transcriptional signatures in each compartment. The relative absence of cytotoxic cells in the lung suggests a model in which delayed clearance of the virus may permit exaggerated myeloid cell activation that contributes to disease pathogenesis by the production of inflammatory mediators. The gene expression profiles also identify potential therapeutic targets that could be modified with available drugs. The data suggest that transcriptomic profiling can provide an understanding of the pathogenesis of COVID-19 in individual patients. Graphical Abstract

positive: Will we see protection or reinfection in COVID-19?

positive: Hypothesis for potential pathogenesis of SARS-CoV-2 infection–a review of immune changes in patients with viral pneumonia Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with droplets and contact as the main means of transmission. Since the first case appeared in Wuhan, China, in December 2019, the outbreak has gradually spread nationwide. Up to now, according to official data released by the Chinese health commission, the number of newly diagnosed patients has been declining, and the epidemic is gradually being controlled. Although most patients have mild symptoms and good prognosis after infection, some patients developed severe and die from multiple organ complications. The pathogenesis of SARS-CoV-2 infection in humans remains unclear. Immune function is a strong defense against invasive pathogens and there is currently no specific antiviral drug against the virus. This article reviews the immunological changes of coronaviruses like SARS, MERS and other viral pneumonia similar to SARS-CoV-2. Combined with the published literature, the potential pathogenesis of COVID-19 is inferred, and the treatment recommendations for giving high-doses intravenous immunoglobulin and low-molecular-weight heparin anticoagulant therapy to severe type patients are proposed.

positive: Comparative evaluation of two severe acute respiratory syndrome (SARS) vaccine candidates in mice challenged with SARS coronavirus. Two different severe acute respiratory syndrome (SARS) vaccine strategies were evaluated for their ability to protect against live SARS coronavirus (CoV) challenge in a murine model of infection. A whole killed (inactivated by beta-propiolactone) SARS-CoV vaccine and a combination of two adenovirus-based vectors, one expressing the nucleocapsid (N) and the other expressing the spike (S) protein (collectively designated Ad S/N), were evaluated for the induction of serum neutralizing antibodies and cellular immune responses and their ability to protect against pulmonary SARS-CoV replication. The whole killed virus (WKV) vaccine given subcutaneously to 129S6/SvEv mice was more effective than the Ad S/N vaccine administered either intranasally or intramuscularly in inhibiting SARS-CoV replication in the murine respiratory tract. This protective ability of the WKV vaccine correlated with the induction of high serum neutralizing-antibody titres, but not with cellular immune responses as measured by gamma interferon secretion by mouse splenocytes. Titres of serum neutralizing antibodies induced by the Ad S/N vaccine administered intranasally or intramuscularly were significantly lower than those induced by the WKV vaccine. However, Ad S/N administered intranasally, but not intramuscularly, significantly limited SARS-CoV replication in the lungs. Among the vaccine groups, SARS-CoV-specific IgA was found only in the sera of mice immunized intranasally with Ad S/N, suggesting that mucosal immunity may play a role in protection for the intranasal Ad S/N delivery system. Finally, the sera of vaccinated mice contained antibodies to S, further suggesting a role for this protein in conferring protective immunity against SARS-CoV infection.

positive: Vaccine repurposing approach for preventing COVID 19: can MMR vaccines reduce morbidity and mortality? The coronavirus disease (COVID-19) is resulting in millions of infected individuals with several hundred thousands dead throughout the world. Amidst all the havoc, one interesting observation in the present COVID-19 pandemic is the negligible symptoms in the young; particularly children below 10 years of age. We assume the extensive pediatric vaccination with MMR vaccines followed globally could have resulted in innate immune responses, e.g., induction of interferons (IFNs) and activated natural killer (NK) cells, thereby offering natural immunity against SARS-CoV-2 in the young population. Possible cross-protective innate immunity offered by MMR vaccination prompted us to suggest repurposing MMR vaccination for immuno-prophylaxis against COVID-19.

positive: Clinical performance of different SARS‐CoV‐2 IgG antibody tests SARS‐CoV‐2 serological assays are urgently needed for rapid diagnosis, contact tracing and for epidemiological studies. So far, there is limited data on how commercially available tests perform with real patient samples and if positive tested samples show neutralizing abilities. Focusing on IgG antibodies, we demonstrate the performance of two ELISA assays (Euroimmun SARS‐CoV‐2 IgG and Vircell COVID‐19 ELISA IgG) in comparison to one lateral flow assay ((LFA) FaStep COVID‐19 IgG/IgM Rapid Test Device) and two in‐house developed assays (immunofluorescence assay (IFA) and plaque reduction neutralization test (PRNT)). We tested follow up serum/plasma samples of individuals PCR‐diagnosed with COVID‐19. Most of the SARS‐CoV‐2 samples were from individuals with moderate to severe clinical course, who required an in‐patient hospital stay. For all examined assays, the sensitivity ranged from 58.8 to 76.5% for the early phase of infection (days 5‐9) and from 93.8 to 100% for the later period (days 10‐18). With exception of one sample, all positive tested COVID‐19 follow up‐samples, using the commercially available assays examined (including the in‐house developed IFA), demonstrated neutralizing properties in the PRNT. Regarding specificity, some samples of endemic coronavirus (HCoV‐OC43, HCoV‐229E) and Epstein Barr virus (EBV) infected individuals cross‐reacted in the ELISA assays and IFA, in one case generating a false positive result. This article is protected by copyright. All rights reserved.

positive: Highly sensitive and specific multiplex antibody assays to quantify immunoglobulins M, A and G against SARS-CoV-2 antigens Reliable serological tests are required to determine the prevalence of antibodies against SARS-CoV-2 antigens and to characterise immunity to the disease in order to address key knowledge gaps in the context of the COVID-19 pandemic. Quantitative suspension array technology (qSAT) assays based on the xMAP Luminex platform overcome the limitations of rapid diagnostic tests and ELISA with their higher precision, dynamic range, throughput, miniaturization, cost-efficacy and multiplexing capacity. We developed three qSAT assays to detect IgM, IgA and IgG to a panel of eight SARS-CoV-2 antigens including spike (S), nucleoprotein (N) and membrane (M) protein constructs. The assays were optimized to minimize processing time and maximize signal to noise ratio. We evaluated the performance of the assays using 128 plasmas obtained before the COVID-19 pandemic (negative controls) and 115 plasmas from individuals with SARS-CoV-2 diagnosis (positive controls), of whom 8 were asymptomatic, 58 had mild symptoms and 49 were hospitalized. Pre-existing IgG antibodies recognizing N, M and S2 proteins were detected in negative controls suggestive of cross-reactive to common cold coronaviruses. The best performing antibody isotype/antigen signatures had specificities of 100% and sensitivities of 94.94% at ≥14 days since the onset of symptoms and 96.08% at ≥21 days since the onset of symptoms, with AUC of 0.992 and 0.999, respectively. Combining multiple antibody markers as assessed by qSAT assays has the highest efficiency, breadth and versatility to accurately detect low-level antibody responses for obtaining reliable data on prevalence of exposure to novel pathogens in a population. Our assays will allow gaining insights into antibody correlates of immunity required for vaccine development to combat pandemics like the COVID-19.

positive: Serological differentiation between COVID-19 and SARS infections In response to the coronavirus disease 2019 (COVID-19) outbreak, caused by SARS-CoV-2, multiple diagnostic tests are required for acute disease diagnosis, contact tracing, monitoring asymptomatic infection rates and assessing herd immunity. While PCR remains the frontline test of choice in the acute diagnostic setting, serological tests are urgently needed. Unlike PCR tests which are highly specific, cross-reactivity is a major challenge for COVID-19 antibody tests considering there are six other coronaviruses known to infect humans. SARS-CoV is genetically related to SARS-CoV-2 sharing approximately 80% sequence identity and both belong to the species SARS related coronavirus in the genus Betacoronavirus of family Coronaviridae. We developed and compared the performance of four different serological tests to comprehensively assess the cross-reactivity between COVID-19 and SARS patient sera. There is significant cross-reactivity when N protein of either virus is used. The S1 or RBD regions from the spike (S) protein offers better specificity. Amongst the different platforms, capture ELISA performed best. We found that SARS survivors all have significant levels of antibodies remaining in their blood 17 years after infection. Anti-N antibodies waned more than anti-RBD antibodies, and the latter is known to play a more important role in providing protective immunity.

positive: Vaccination of mice with recombinant baculovirus expressing spike or nucleocapsid protein of SARS-like coronavirus generates humoral and cellular immune responses Abstract Continuous efforts have been made to develop a prophylactic vaccine against severe acute respiratory syndrome coronavirus (SARS-CoV). In this study, two recombinant baculoviruses, vAc-N and vAc-S, were constructed, which contained the mammalian-cell activate promoter element, human elongation factor 1α-subunit (EF-1α), the human cytomegalovirus (CMV) immediate-early promoter, and the nucleocapsid (N) or spike (S) gene of bat SARS-like CoV (SL-CoV) under the control of the CMV promoter. Mice were subcutaneously and intraperitoneally injected with recombinant baculovirus, and both humoral and cellular immune responses were induced in the vaccinated groups. The secretion level of IFN-γ was much higher than that of IL-4 in vAc-N or vAc-S immunized groups, suggesting a strong Th1 bias towards cellular immune responses. Additionally, a marked increase of CD4 T cell immune responses and high levels of anti-SARS-CoV humoral responses were also detected in the vAc-N or vAc-S immunized groups. In contrast, there were significantly weaker cellular immune responses, as well as less antibody production than in the control groups. Our data demonstrates that the recombinant baculovirus can serve as an effective vaccine strategy. In addition, because effective SARS vaccines should act to not only prevent the reemergence of SARS-CoV, but also to provide cross-protection against SL-CoV, findings in this study may have implications for developing such cross-protective vaccines.

positive: Development of antiviral therapy for severe acute respiratory syndrome Abstract A new disease, the severe acute respiratory distress syndrome (SARS), caused by the SARS coronavirus (SARS-CoV), emerged at the beginning of 2003 and rapidly spread throughout the world. Although the disease had disappeared in June 2003 its re-emergence cannot be excluded. The development of vaccines against SARS-CoV may take years. Therefore, the availability of effective antiviral drugs against SARS-CoV may be crucial for the control of future SARS outbreaks. In this review, experimental and clinical data about potential anti-SARS drugs is summarised and discussed. Animal model studies will be needed to help to determine which interventions warrant controlled clinical testing.

positive: Immunologic aspects of characteristics, diagnosis, and treatment of coronavirus disease 2019 (COVID-19) On March 11, 2020, the World Health Organization declared the worldwide spread of the infectious disease COVID-19, caused by a new strain of coronavirus, SARS-CoV-2, as a pandemic. Like in all other infectious diseases, the host immune system plays a key role in our defense against SARS-CoV-2 infection. However, viruses are able to evade the immune attack and proliferate and, in susceptible individuals, cause severe inflammatory response known as cytokine storm, particularly in the lungs. The advancement in our understanding of the mechanisms underlying the host immune responses promises to facilitate the development of approaches for prevention or treatment of diseases. Components of immune system, such as antibodies, can also be used to develop sensitive and specific diagnostic methods as well as novel therapeutic agents. In this review, we summarize our knowledge about how the host mounts immune responses to infection by SARS-CoV-2. We also describe the diagnostic methods being used for COVID-19 identification and summarize the current status of various therapeutic strategies, including vaccination, being considered for treatment of the disease.

positive: A molecular arms race between host innate antiviral response and emerging human coronaviruses Coronaviruses have been closely related with mankind for thousands of years. Communityacquired human coronaviruses have long been recognized to cause common cold. However, zoonotic coronaviruses are now becoming more a global concern with the discovery of highly pathogenic severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) coronaviruses causing severe respiratory diseases. Infections by these emerging human coronaviruses are characterized by less robust interferon production. Treatment of patients with recombinant interferon regimen promises beneficial outcomes, suggesting that compromised interferon expression might contribute at least partially to the severity of disease. The mechanisms by which coronaviruses evade host innate antiviral response are under intense investigations. This review focuses on the fierce arms race between host innate antiviral immunity and emerging human coronaviruses. Particularly, the host pathogen recognition receptors and the signal transduction pathways to mount an effective antiviral response against SARS and MERS coronavirus infection are discussed. On the other hand, the counter-measures evolved by SARS and MERS coronaviruses to circumvent host defense are also dissected. With a better understanding of the dynamic interaction between host and coronaviruses, it is hoped that insights on the pathogenesis of newly-identified highly pathogenic human coronaviruses and new strategies in antiviral development can be derived. [Image: see text]

positive: PCR sequencing of the spike genes of geographically and chronologically distinct human coronaviruses 229E Abstract A reverse transcription nested PCR (RT-PCR) sequencing methodology was developed and used to generate sequence data from the spike genes of three geographically and chronologically distinct human coronaviruses 229E. These three coronaviruses were isolated originally from the USA in the 1960s (human coronavirus 229E strain ATCC VR-74), the UK in the 1990s (human coronavirus 229E LRI 281) and Ghana (human coronavirus 229E A162). Upon translation and alignment with the published spike protein sequence of human coronavirus 229E ‘LP’ (isolated in the UK in the 1970s), it was found that variation within the translated protein sequences was rather limited. In particular, minimal variation was observed between the translated spike protein sequence of human coronaviruses 229E LP and ATCC VR-74 (1/1012 amino acid differences), whilst most variation was observed between the translated spike protein sequence of human coronaviruses 229E LP and A162 (47/1012 amino acid changes). Further, the translated spike protein sequence of human coronavirus 229E A162 showed three clusters of amino acid changes, situated within the 5′ half of the translated spike protein sequence.

positive: Contribution of antibody-secreting cells induced in mucosal lymphoid tissues of pigs inoculated with respiratory or enteric strains of coronavirus to immunity against enteric coronavirus challenge. Two antigenically related porcine coronaviruses, transmissible gastroenteritis virus (TGEV) which infects primarily the intestinal tract and causes severe diarrhea, and porcine respiratory coronavirus (PRCV) which infects the respiratory tract and causes subclinical or mild respiratory infections, presented a unique opportunity to study the interrelationship of gut-(GALT) and bronchus-associated lymphoid tissues (BALT) and their contribution to protective immunity against TGEV infection. Pigs were inoculated oral-nasally with TGEV or with PRCV at eleven days of age and challenged 24 days later with TGEV. All pigs initially given TGEV developed diarrhea and were completely protected against disease upon challenge. In contrast, pigs given PRCV had no clinical disease and shed virus in nasal secretions only; after challenge, 5 of 12 pigs developed diarrhea. Virus-specific IgG and IgA Ab-secreting cells (ASC) were enumerated by ELISPOT in the mesenteric and bronchial lymph nodes, spleens, and gut lamina propria at challenge and various post challenge days. Before challenge, in pigs exposed to TGEV, IgA-ASC in the duodenum and jejunum constituted the major ASC response. Conversely, PRCV-exposed pigs had mainly IgG-ASC in bronchial lymph nodes, with low ASC responses in the gut. After challenge, numbers of IgG-ASC increased rapidly in the gut lamina propria and mesenteric lymph nodes of only PRCV-primed pigs. Our results suggest that virus-specific IgG-ASC precursors derived in BALT of PRCV-primed pigs may migrate to the gut in response to TGEV challenge and contribute to the partial protection observed. The presence of IgA-ASC in the gut lamina propria of TGEV-primed pigs at the time of challenge correlated with complete protection against TGEV challenge. Thus a dichotomy exists in the BALT and GALT ASC responses; immunization via BALT induced a systemic type of response (IgG-ASC) and provided imperfect protection against an enteric pathogen, whereas immunization via GALT induced IgA-ASC and provided complete protection.

positive: Trained Immunity: a Tool for Reducing Susceptibility to and the Severity of SARS-CoV-2 Infection SARS-CoV-2 infection is mild in the majority of individuals but progresses into severe pneumonia in a small proportion of patients. The increased susceptibility to severe disease in the elderly and individuals with co-morbidities argues for an initial defect in anti-viral host defense mechanisms. Long-term boosting of innate immune responses, also termed "trained immunity," by certain live vaccines (BCG, oral polio vaccine, measles) induces heterologous protection against infections through epigenetic, transcriptional, and functional reprogramming of innate immune cells. We propose that induction of trained immunity by whole-microorganism vaccines may represent an important tool for reducing susceptibility to and severity of SARS-CoV-2.

positive: Identification of murine CD8 T cell epitopes in codon-optimized SARS-associated coronavirus spike protein Abstract The causative agent of severe acute respiratory syndrome (SARS) has been identified as a new type of coronavirus, SARS-associated coronavirus (SARS-CoV). CD8 T cells play an important role in controlling diseases caused by other coronaviruses and in mediating vaccine-induced protective immunity in corresponding animal models. The spike protein, a main surface antigen of SARS-CoV, is one of the most important antigen candidates for vaccine design. Overlapping peptides were used to identify major histocompatibility complex class I-restricted epitopes in mice immunized with vectors encoding codon-optimized SARS-CoV spike protein. CD8 T-cell responses were mapped to two H-2b-restricted epitopes (S436–443 and S525–532) and one H-2d-restricted epitope (S366–374). The identification of these epitopes will facilitate the evaluation of vaccine strategies in murine models of SARS-CoV infection. Furthermore, codon and promoter optimizations can greatly enhance the overall immunogenicity of spike protein in the context of replication-defective human and simian adenoviral vaccine carriers. The optimized recombinant adenoviral vaccine vectors encoding spike can generate robust antigen-specific cellular immunity in mice and may potentially be useful for control of SARS-CoV infection.

positive: Humoral Immune Responses in COVID-19 Patients: A Window on the State of the Art The novel SARS-CoV-2 is a recently emerging virus causing a human pandemic. A great variety of symptoms associated with COVID-19 disease, ranging from mild to severe symptoms, eventually leading to death. Specific SARS-CoV-2 RT-PCR is the standard method to screen symptomatic people; however, asymptomatic subjects and subjects with undetectable viral load escape from the screening, contributing to viral spread. Currently, the lock down imposed by many governments is an important measure to contain the spread, as there is no specific antiviral therapy or a vaccine and the main treatments are supportive. Therefore, there is urgent need to characterize the virus and the viral-mediated responses, in order to develop specific diagnostic and therapeutic tools to prevent viral transmission and efficiently cure COVID-19 patients. Here, we review the current studies on two viral mediated-responses, specifically the cytokine storm occurring in a subset of patients and the antibody response triggered by the infection. Further studies are needed to explore both the dynamics and the mechanisms of the humoral immune response in COVID-19 patients, in order to guide future vaccine design and antibody-based therapies for the management of the disease.

positive: NK cells: A double edge sword against SARS-CoV-2 Natural killer (NK) cells are pivotal effectors of the innate immunity protecting an individual from microbes. They are the first line of defense against invading viruses, given their substantial ability to directly target infected cells without the need for specific antigen presentation. By establishing cellular networks with a variety of cell types such as dendritic cells, NK cells can also amplify and modulate antiviral adaptive immune responses. In this review, we will examine the role of NK cells in SARS-COV2 infections causing the ongoing COVID19 pandemic, keeping in mind the controversial role of NK cells specifically in viral respiratory infections and in inflammatory-driven lung damage. We discuss lessons learnt from previous coronavirus outbreaks in humans (caused by SARS-CoV-1 and MERS-COV).

positive: Immunodominant viral peptides as determinants of cross-reactivity in the immune system – Can we develop wide spectrum viral vaccines? Summary When we look back to Edward Jenner vaccination of a young man in 1796, we cannot help thinking that he was both lucky and crazy. Crazy because he decided to test in a human being a hypothesis based mainly in the traditional belief that people who had acquired cowpox from the udders of a cow were thereafter resistant to smallpox, a quite devastating disease, and lucky because (even considering that he did not know this at that time) he succeeded to induce protection against a pathogen through the induction of an immune response directed against a different agent. Not only was he able to protect the young man but he took the first step towards the development of a vast new field, vaccination. It is acceptable to say that Jenner was lucky because he succeeded in promoting protection against smallpox using a cowpox virus and this induction of protection in a cross-reactive way is believed to be quite rare. Nevertheless, more and more examples of cross-reactive immune responses are being described and we are beginning to admit that cross-reactivity is far more common and important than we used to think. Here we review cross-reactivity in the immune system and the plasticity of T cell recognition. Based on the existence of T cell receptor promiscuous recognition and cross-recognition of conserved viral immunodominant epitopes, we propose two approaches to develop wide spectrum viral vaccines. The first one is based on the identification, characterization, and cloning of immunodominant viral epitopes able to stimulate responses against different viruses. The produced peptides could then be purified and serve as a basis for vaccine therapies. A second strategy is based on the identification of conserved patterns in immunodominant viral peptides and the production of synthetic peptides containing the amino acid residues necessary for MHC anchoring and TCR contact. Although we are still far from a complete knowledge of the cross-reactivity phenomenon in the immune system, the analysis of immunodominant viral epitopes and the identification of particular “viral patterns” seems to be important steps towards the development of wide spectrum viral vaccines.

positive: A case report of possible novel coronavirus 2019 reinfection Since December 2019, COVID-19, the clinical syndrome associated with SARS-CoV-2 infection, has infected more than 6.2 million people and brought the function of the global community to a halt. As the number of patients recovered from COVID-19 rises and the world transitions toward reopening, the question of acquired immunity versus the possibility of reinfection are critical to anticipating future viral spread. Here, we present a case of a patient previously recovered from COVID-19 who re-presents with new respiratory, radiographical, laboratory, and RT-PCR findings concerning for re-infection. We review this case in the context of the evolving discussion and theories surrounding dynamic RT-PCR results, prolonged viral shedding, and the possibility of developed immunity.

positive: Potential biases arising from epidemic dynamics in observational seroprotection studies The extent and duration of immunity following SARS-CoV-2 infection are critical outstanding questions about the epidemiology of this novel virus, and studies are needed to evaluate the effects of serostatus on reinfection. Understanding the potential sources of bias and methods to alleviate biases in these studies is important for informing their design and analysis. Confounding by individual-level risk factors in observational studies like these is relatively well appreciated. Here, we show how geographic structure and the underlying, natural dynamics of epidemics can also induce noncausal associations. We take the approach of simulating serologic studies in the context of an uncontrolled or a controlled epidemic, under different assumptions about whether prior infection does or does not protect an individual against subsequent infection, and using various designs and analytic approaches to analyze the simulated data. We find that in studies assessing the efficacy of serostatus on future infection, comparing seropositive individuals to seronegative individuals with similar time-dependent patterns of exposure to infection, by stratifying or matching on geographic location and time of enrollment, is essential to prevent bias.

positive: Fully human single-domain antibodies against SARS-CoV-2 The COVID-19 pandemic is spreading rapidly, highlighting the urgent need for an efficient approach to rapidly develop therapeutics and prophylactics against SARS-CoV-2. We describe here the development of a phage-displayed single-domain antibody library by grafting naïve CDRs into framework regions of an identified human germline IGHV allele. This enabled the isolation of high-affinity single-domain antibodies of fully human origin. The panning using SARS-CoV-2 RBD and S1 as antigens resulted in the identification of antibodies targeting five types of neutralizing or non-neutralizing epitopes on SARS-CoV-2 RBD. These fully human single-domain antibodies bound specifically to SARS-CoV-2 RBD with subnanomolar to low nanomolar affinities. Some of them were found to potently neutralize pseudotyped and live virus, and therefore may represent promising candidates for prophylaxis and therapy of COVID-19. This study also reports unique immunogenic profile of SARS-CoV-2 RBD compared to that of SARS-CoV and MERS-CoV, which may have important implications for the development of effective vaccines against SARS-CoV-2.

positive: Individual variation in susceptibility or exposure to SARS-CoV-2 lowers the herd immunity threshold As severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spreads, the susceptible subpopulation is depleted causing the incidence of new cases to decline. Variation in individual susceptibility or exposure to infection exacerbates this effect. Individuals that are more susceptible or more exposed tend to be infected earlier, depleting the susceptible subpopulation of those who are at higher risk of infection. This selective depletion of susceptibles intensifies the deceleration in incidence. Eventually, susceptible numbers become low enough to prevent epidemic growth or, in other words, the herd immunity threshold (HIT) is reached. Although estimates vary, simple calculations suggest that herd immunity to SARS-CoV-2 requires 60-70% of the population to be immune. By fitting epidemiological models that allow for heterogeneity to SARS-CoV-2 outbreaks across the globe, we show that variation in susceptibility or exposure to infection reduces these estimates. Accurate measurements of heterogeneity are therefore of paramount importance in controlling the COVID-19 pandemic.

positive: Immunity Passports for SARS-CoV-2: an online experimental study of the impact of antibody test terminology on perceived risk and behaviour Objective: To assess the impact of describing an antibody-positive test result using the terms Immunity and Passport or Certificate, alone or in combination, on perceived risk of becoming infected with SARS-CoV-2 and intention to continue protective behaviours. Design: 2 by 3 experimental design. Setting: Online with data collected between 28th April and 1st May 2020. Participants: 1,204 adults registered with a UK research panel. Intervention: Participants were randomised to receive one of six descriptions of an antibody test and results showing SARS-CoV-2 antibodies, differing in the terms used to describe the type of test (Immunity vs Antibody) and the test result (Passport vs Certificate vs Test). Main outcome measures: The primary outcome was the proportion of participants perceiving no risk of becoming infected with SARS-CoV-2 given an antibody positive test result. Other outcomes include intended changes to frequency of hand washing and physical distancing. Results: When using the term Immunity (vs Antibody), 19.1% of participants [95% CI: 16.1 to 22.5] (vs 9.8% [95% CI: 7.5 to 12.4]) perceived no risk of catching coronavirus at some point in the future given an antibody-positive test result (AOR: 2.91 [95% CI: 1.52 to 5.55]). Using the terms Passport or Certificate, as opposed to Test, had no significant effect (AOR: 1.24 [95% CI: 0.62 to 2.48] and AOR: 0.96 [95% CI: 0.47 to 1.99] respectively). There was no significant interaction between the effects of the test and result terminology. Across groups, perceiving no risk of infection was associated with an intention to wash hands less frequently (AOR: 2.32 [95% CI: 1.25 to 4.28]) but there was no significant association with intended avoidance of physical contact with others outside of the home (AOR: 1.37 [95% CI: 0.93 to 2.03]). Conclusions: Using the term Immunity (vs Antibody) to describe antibody tests for SARS-CoV-2 increases the proportion of people believing that an antibody-positive result means they have no risk of catching coronavirus in the future, a perception that may be associated with less frequent hand washing. The way antibody testing is described may have implications for the likely impact of testing on transmission rates.

positive: Characterization of SARS-CoV-specific memory T cells from recovered individuals 4 years after infection SARS-CoV infection of human results in antigen-specific cellular and humoral immune responses. However, it is critical to determine whether SARS-CoV-specific memory T cells can persist for long periods of time. In this study, we analyzed the cellular immune response from 21 SARS-recovered individuals who had been diagnosed with SARS in 2003 by using ELISA, CBA, ELISpot and multiparameter flow cytometry assays. Our results demonstrated that low levels of specific memory T cell responses to SARS-CoV S, M, E and N peptides were detected in a proportion of SARS-recovered patients, and IFN-γ was the predominant cytokine produced by T cells after stimulation with peptides. Cytometry analysis indicated that the majority of memory CD8(+) T cells produced IFN-γ, whereas memory CD4(+) T cells produced IFN-γ, IL-2 or TNF-α. These results might provide valuable information on the cellular immune response in recovered SARS-CoV patients for the rational design of vaccines against SARS-CoV infection.

positive: Analysis of SARS-CoV-2 Antibodies in COVID-19 Convalescent Plasma using a Coronavirus Antigen Microarray The current practice for diagnosis of COVID-19, based on SARS-CoV-2 PCR testing of pharyngeal or respiratory specimens in a symptomatic patient at high epidemiologic risk, likely underestimates the true prevalence of infection. Serologic methods can more accurately estimate the disease burden by detecting infections missed by the limited testing performed to date. Here, we describe the validation of a coronavirus antigen microarray containing immunologically significant antigens from SARS-CoV-2, in addition to SARS-CoV, MERS-CoV, common human coronavirus strains, and other common respiratory viruses. A comparison of antibody profiles detected on the array from control sera collected prior to the SARS-CoV-2 pandemic versus convalescent blood specimens from virologically confirmed COVID-19 cases demonstrates complete discrimination of these two groups. This array can be used as a diagnostic tool, as an epidemiologic tool to more accurately estimate the disease burden of COVID-19, and as a research tool to correlate antibody responses with clinical outcomes.

positive: Human Leukocyte Antigen Susceptibility Map for Severe Acute Respiratory Syndrome Coronavirus 2 Genetic variability across the three major histocompatibility complex (MHC) class I genes (human leukocyte antigen A [HLA-A], -B, and -C genes) may affect susceptibility to and severity of the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus responsible for coronavirus disease 2019 (COVID-19). We performed a comprehensive in silico analysis of viral peptide-MHC class I binding affinity across 145 HLA-A, -B, and -C genotypes for all SARS-CoV-2 peptides. We further explored the potential for cross-protective immunity conferred by prior exposure to four common human coronaviruses. The SARS-CoV-2 proteome was successfully sampled and was represented by a diversity of HLA alleles. However, we found that HLA-B*46:01 had the fewest predicted binding peptides for SARS-CoV-2, suggesting that individuals with this allele may be particularly vulnerable to COVID-19, as they were previously shown to be for SARS (M. Lin, H.-T. Tseng, J. A. Trejaut, H.-L. Lee, et al., BMC Med Genet 4:9, 2003, https://bmcmedgenet.biomedcentral.com/articles/10.1186/1471-2350-4-9). Conversely, we found that HLA-B*15:03 showed the greatest capacity to present highly conserved SARS-CoV-2 peptides that are shared among common human coronaviruses, suggesting that it could enable cross-protective T-cell-based immunity. Finally, we reported global distributions of HLA types with potential epidemiological ramifications in the setting of the current pandemic. IMPORTANCE Individual genetic variation may help to explain different immune responses to a virus across a population. In particular, understanding how variation in HLA may affect the course of COVID-19 could help identify individuals at higher risk from the disease. HLA typing can be fast and inexpensive. Pairing HLA typing with COVID-19 testing where feasible could improve assessment of severity of viral disease in the population. Following the development of a vaccine against SARS-CoV-2, the virus that causes COVID-19, individuals with high-risk HLA types could be prioritized for vaccination.

positive: Functional Genomics Highlights Differential Induction of Antiviral Pathways in the Lungs of SARS-CoV–Infected Macaques The pathogenesis of severe acute respiratory syndrome coronavirus (SARS-CoV) is likely mediated by disproportional immune responses and the ability of the virus to circumvent innate immunity. Using functional genomics, we analyzed early host responses to SARS-CoV infection in the lungs of adolescent cynomolgus macaques (Macaca fascicularis) that show lung pathology similar to that observed in human adults with SARS. Analysis of gene signatures revealed induction of a strong innate immune response characterized by the stimulation of various cytokine and chemokine genes, including interleukin (IL)-6, IL-8, and IP-10, which corresponds to the host response seen in acute respiratory distress syndrome. As opposed to many in vitro experiments, SARS-CoV induced a wide range of type I interferons (IFNs) and nuclear translocation of phosphorylated signal transducer and activator of transcription 1 in the lungs of macaques. Using immunohistochemistry, we revealed that these antiviral signaling pathways were differentially regulated in distinctive subsets of cells. Our studies emphasize that the induction of early IFN signaling may be critical to confer protection against SARS-CoV infection and highlight the strength of combining functional genomics with immunohistochemistry to further unravel the pathogenesis of SARS.

positive: Perspectives on monoclonal antibody therapy as potential therapeutic intervention for Coronavirus disease-19 (COVID-19). Last decade witnessed the outbreak of many life-threatening human pathogens including Nipah, Ebola, Chikungunya, Zika, Middle East respiratory syndrome coronavirus (MERS-CoV), Severe Acute respiratory syndrome coronavirus (SARS-CoV) and more recently novel coronavirus (2019-nCoV or SARS-CoV-2). The disease condition associated with novel coronavirus, referred to as Coronavirus disease (COVID-19). The emergence of novel coronavirus in 2019 in Wuhan, China marked the third highly pathogenic coronavirus infecting humans in the 21st century. The continuing emergence of coronaviruses at regular intervals poses a significant threat to human health and economy. Ironically, even after a decade of research on coronavirus, still there are no licensed vaccines or therapeutic agents to treat coronavirus infection which highlights an urgent need to develop effective vaccines or post-exposure prophylaxis to prevent future epidemics. Several clinical, genetic and epidemiological features of COVID-19 resemble SARS-CoV infection. Hence, the research advancements on SARS-CoV treatment might help scientific community in quick understanding of this virus pathogenesis and develop effective therapeutic/prophylactic agents to treat and prevent this infection. Monoclonal antibodies represent the major class of biotherapeutics for passive immunotherapy to fight against viral infection. The therapeutic potential of monoclonal antibodies has been well recognized in the treatment of many diseases. Here, we summarize the potential monoclonal antibody based therapeutic intervention for COVID-19 by considering the existing knowledge on the neutralizing monoclonal antibodies against similar coronaviruses SARS-CoV and MERS-CoV. Further research on COVID-19 pathogenesis could identify appropriate therapeutic targets to develop specific anti-virals against this newly emerging pathogen.

positive: Anti-SARS-CoV immunity induced by a novel CpG oligodeoxynucleotide Abstract To develop CpG oligodeoxynucleotides (CpG ODNs) based therapy for prevention and treatment of severe acute respiratory syndrome (SARS), we selected a novel CpG ODN (BW001), which displays B-type CpG ODN structure feature at the 5′ and A-type CpG ODN structure feature at the 3′, and tested for its anti-SARS-CoV activity. We found that the supernatants of human PBMCs stimulated by BW001 significantly protected Vero cells from SARS-CoV infection. BW001 could stimulate human PBMCs and pDCs to secrete high level of IFN-α and promote human PBMCs and B cells to proliferate. Furthermore, we demonstrated that BW001 could activate CD19+ B cells and CD56+ NK cells in human PBMCs. In addition, BW001 could enhance NK cytotoxicity and IFN-γ secretion in human PBMCs. Together, BW001 represents a novel type of CpG ODN and may have potential for the development of treatment and prevention for SARS as well as other viral associated diseases.

positive: Coronavirus Immunity: From T Cells to B Cells

positive: Clinical performance of SARS-CoV-2 IgG antibody tests and potential protective immunity As the current SARS-CoV-2 pandemic continues, serological assays are urgently needed for rapid diagnosis, contact tracing and for epidemiological studies. So far, there is little data on how commercially available tests perform with real patient samples and if detected IgG antibodies provide protective immunity. Focusing on IgG antibodies, we demonstrate the performance of two ELISA assays (Euroimmun SARS-CoV-2 IgG & Vircell COVID-19 ELISA IgG) in comparison to one lateral flow assay ((LFA) FaStep COVID-19 IgG/IgM Rapid Test Device) and two in-house developed assays (immunofluorescence assay (IFA) and plaque reduction neutralization test (PRNT)). We tested follow up serum/plasma samples of individuals PCR-diagnosed with COVID-19. Most of the SARS-CoV-2 samples were from individuals with moderate to severe clinical course, who required an in-patient hospital stay. For all examined assays, the sensitivity ranged from 58.8 to 76.5% for the early phase of infection (days 5-9) and from 93.8 to 100% for the later period (days 10-18) after PCR-diagnosed with COVID-19. With exception of one sample, all positive tested samples in the analysed cohort, using the commercially available assays examined (including the in-house developed IFA), demonstrated neutralizing (protective) properties in the PRNT, indicating a potential protective immunity to SARS-CoV-2. Regarding specificity, there was evidence that samples of endemic coronavirus (HCoV-OC43, HCoV-229E) and Epstein Barr virus (EBV) infected individuals cross-reacted in the ELISA assays and IFA, in one case generating a false positive result (may giving a false sense of security). This need to be further investigated.

positive: Recent Advances in the Vaccine Development Against Middle East Respiratory Syndrome-Coronavirus Middle East respiratory syndrome (MERS) is a deadly viral respiratory disease caused by MERS-coronavirus (MERS-CoV) infection. To date, there is no specific treatment proven effective against this viral disease. In addition, no vaccine has been licensed to prevent MERS-CoV infection thus far. Therefore, our current review focuses on the most recent studies in search of an effective MERS vaccine. Overall, vaccine candidates against MERS-CoV are mainly based upon the viral spike (S) protein, due to its vital role in the viral infectivity, although several studies focused on other viral proteins such as the nucleocapsid (N) protein, envelope (E) protein, and non-structural protein 16 (NSP16) have also been reported. In general, the potential vaccine candidates can be classified into six types: viral vector-based vaccine, DNA vaccine, subunit vaccine, nanoparticle-based vaccine, inactivated-whole virus vaccine and live-attenuated vaccine, which are discussed in detail. Besides, the immune responses and potential antibody dependent enhancement of MERS-CoV infection are extensively reviewed. In addition, animal models used to study MERS-CoV and evaluate the vaccine candidates are discussed intensively.

positive: The laboratory tests and host immunity of COVID-19 patients with different severity of illness. BACKGROUND The Coronavirus Disease-2019 (COVID-19), infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has caused a severe outbreak in China. The host immunity of COVID-19 patients is unknown. METHODS The routine laboratory tests and host immunity in COVID-19 patients with different severity of illness were compared after patient admission. RESULTS A total of 65 SARS-CoV-2-positive patients were classified as mild (n=30), severe (n=20), and extremely severe (n=15) illness. Many routine laboratory tests such as ferritin, lactate dehydrogenase and D-dimer were increased in severe and extremely severe patients. The absolute numbers of CD4+ T cells, CD8+ T cells and B cells were all gradually decreased with increased severity of illness. The activation markers such as HLA-DR and CD45RO expressed on CD4+ and CD8+ T cells were increased in severe and extremely severe patients compared with mild patients. The co-stimulatory molecule CD28 had opposite results. The percentage of natural regulatory T cells was decreased in extremely severe patients. The percentage of IFN-γ producing CD8+ T cells was increased in both severe and extremely severe patients compared with mild patients. The percentage of IFN-γ producing CD4+ T cells was increased in extremely severe patients. The IL-2R, IL-6, and IL-10 were all increased in extremely severe patients. The activation of DC and B cells was decreased in extremely severe patients. CONCLUSIONS The number and function of T cells are inconsistent in COVID-19 patients. The hyperfunction of CD4+ and CD8+ T cells is associated with the pathogenesis of extremely severe SARS-CoV-2 infection.

positive: Passive Immunity for Coronavirus Disease 2019: A Commentary on Therapeutic Aspects Including Convalescent Plasma In the ongoing pandemic of coronavirus disease 2019 (COVID-19), the novel virus SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) is infecting a naïve population. The innate immunity of the infected patient is unable to mount an effective defense, resulting in a severe illness with substantial morbidity and mortality. As most treatment modalities including antivirals and anti-inflammatory agents are mostly ineffective, an immunological approach is needed. The mechanism of innate immunity to this viral illness is not fully understood. Passive immunity becomes an important avenue for the management of these patients. In this article, the immune responses of COVID-19 patients are reviewed. As SARS-CoV-2 has many characteristics in common with two other viruses, SARS-CoV that cause severe acute respiratory syndrome (SARS) and MERS-CoV (Middle East respiratory syndrome coronavirus) that causes Middle East respiratory syndrome (MERS), the experiences learned from the use of passive immunity in treatment can be applied to COVID-19. The immune response includes the appearance of immunoglobulin M followed by immunoglobulin G and neutralizing antibodies. Convalescent plasma obtained from patients recovered from the illness with high titers of neutralizing antibodies was successful in treating many COVID-19 patients. The factors that determine responses as compared with those seen in SARS and MERS are also reviewed. As there are no approved vaccines against all three viruses, it remains a challenge in the ongoing development for an effective vaccine for COVID-19.

positive: Escape from Human Monoclonal Antibody Neutralization Affects In Vitro and In Vivo Fitness of Severe Acute Respiratory Syndrome Coronavirus BACKGROUND: Severe Acute Respiratory Syndrome (SARS) emerged as a human disease in 2002 and detailed phylogenetic analysis and epidemiological studies have suggested that the SARS-Coronavirus (SARS-CoV) originated from animals. The Spike (S) glycoprotein has been identified as a major target of protective immunity and contains at least three regions that are targeted by neutralizing antibodies in the S1 and S2 domains. We previously characterized a panel of neutralizing human monoclonal antibodies (MAbs) but the majority of epitopes recognized by the MAbs remained unknown. METHODS: In this study we generated neutralization escape mutants and studied the effect of these neutralization escape mutations on human and animal receptor usage as well as in vitro and in vivo fitness. RESULTS: Distinct but partially overlapping sets of amino acids were identified that are critical to the binding of MAbs with differential neutralization profiles. We also identified possible interactions between the S1 and S2 domains of the SARS-CoV S glycoprotein. Finally, we showed that escape from neutralization usually attenuates SARS-CoV infection. CONCLUSIONS: These data provide a mechanism to overcome neutralization escape by using broadly cross reactive cocktails of cross-neutralizing MAbs that recognize residues within the receptor binding domain, critical for virus replication and virulence.

positive: Protective Adaptive Immunity Against Severe Acute Respiratory Syndrome Coronaviruses 2 (SARS-CoV-2) and Implications for Vaccines Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an emerging human coronavirus responsible for coronavirus disease 2019 (COVID-19), a predominantly respiratory disease that has become a global pandemic. Millions of people worldwide are suffering from COVID-19, and hundreds of thousands of those infected have died. Nevertheless, many more people who have been infected with SARS-CoV-2 are asymptomatic or suffer a mild disease characterized by dry cough and mild fever. This new pandemic poses a threat to public health on a global scale, and an intervention to prevent continued spread of SARS-CoV-2 virus is of the utmost importance. To assess preventive and therapeutic strategies, it is imperative to understand the pathogenesis and immune response against SARS-CoV-2. In this review, we concentrate on the protective adaptive immune response elicited by this novel coronavirus as well as requirements for a successful vaccine inducing optimal protection.

positive: Correspondence regarding recently published editorial: ‘Will children reveal their secret? The coronavirus dilemma’ When individuals without prior immunity are considered, case fatality ratios are typically higher in adults than in children for most infectious diseases, with few exceptions.

positive: Recombinant receptor-binding domain of SARS-CoV spike protein expressed in mammalian, insect and E. coli cells elicits potent neutralizing antibody and protective immunity Severe acute respiratory syndrome (SARS) is a newly emerging infectious disease. The potential recurrence of the disease from animal reservoirs highlights the significance of development of safe and efficient vaccines to prevent a future SARS epidemic. In this study, we expressed the recombinant receptor-binding domain (rRBD) in mammalian (293T) cells, insect (Sf9) cells, and E. coli, respectively, and compared their immunogenicity and protection against SARS-CoV infection in an established mouse model. Our results show that all rRBD proteins expressed in the above systems maintained intact conformation, being able to induce highly potent neutralizing antibody responses and complete protective immunity against SARS-CoV challenge in mice, albeit the rRBD expressed in 293T cells elicited stronger humoral immune responses with significantly higher neutralizing activity (P < 0.05) than those expressed in Sf9 and E. coli cells. These results suggest that all three rRBDs are effective in eliciting immune responses and protection against SARS-CoV and any of the above expression systems can be used for production of rRBD-based SARS subunit vaccines. Preference will be given to rRBD expressed in mammalian cells for future evaluation of the vaccine efficacy in a non-human primate model of SARS because of its ability to refold into a native conformation more readily and to induce higher level of neutralizing antibody responses than those expressed in E. coli and insect cells.

positive: Vulnerabilities in coronavirus glycan shields despite extensive glycosylation Severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) coronaviruses (CoVs) are zoonotic pathogens with high fatality rates and pandemic potential. Vaccine development has focussed on the principal target of the neutralizing humoral immune response, the spike (S) glycoprotein, which mediates receptor recognition and membrane fusion. Coronavirus S proteins are extensively glycosylated viral fusion proteins, encoding around 69-87 N-linked glycosylation sites per trimeric spike. Using a multifaceted structural approach, we reveal a specific area of high glycan density on MERS S that results in the formation of under-processed oligomannose-type glycan clusters, which was absent on SARS and HKU1 CoVs. We provide a comparison of the global glycan density of coronavirus spikes with other viral proteins including HIV-1 envelope, Lassa virus glycoprotein complex, and influenza hemagglutinin, where glycosylation plays a known role in shielding immunogenic epitopes. Consistent with the ability of the antibody-mediated immune response to effectively target and neutralize coronaviruses, we demonstrate that the glycans of coronavirus spikes are not able to form an efficacious high-density global shield to thwart the humoral immune response. Overall, our data reveal how differential organisation of viral glycosylation across class I viral fusion proteins influence not only individual glycan compositions but also the immunological pressure across the viral protein surface.

positive: Comparative analysis of the immunogenicity of SARS-CoV nucleocapsid DNA vaccine administrated with different routes in mouse model The development of strategies to augment the immunogenicity of DNA vaccines is critical for improving their clinical utility. One such strategy involves using the different immune routes with DNA vaccines. In the present study, the immunogenicity of SARS-CoV nucleocapsid DNA vaccine, induced by using the current routine vaccination routes (intramuscularly, by electroporation, or orally using live-attenuated Salmonella typhimurium), was compared in mouse model. The comparison between the three vaccination routes indicated that immunization intramuscularly induced a moderate T cell response and antibody response. Mice administrated by electroporation induced the highest antibody response among the three immunization groups and a mid-level of cellular response. In contrast, the orally DNA vaccine evoked vigorous T cell response and a weak antibody production. These results indicated that the distinct types of immune responses were generated by the different routes of DNA immunization. In addition, our results also show that the delivery of DNA vaccines by electroporation and orally using live-attenuated Salmonella in vivo is an effective method to increase the immune responses. Further studies could be carried out using a combination strategy of both oral and electroporation immunizations to stimulate higher cellular and humoral immune responses.

positive: Vaccine Efficacy in Senescent Mice Challenged with Recombinant SARS-CoV Bearing Epidemic and Zoonotic Spike Variants BACKGROUND: In 2003, severe acute respiratory syndrome coronavirus (SARS-CoV) was identified as the etiological agent of severe acute respiratory syndrome, a disease characterized by severe pneumonia that sometimes results in death. SARS-CoV is a zoonotic virus that crossed the species barrier, most likely originating from bats or from other species including civets, raccoon dogs, domestic cats, swine, and rodents. A SARS-CoV vaccine should confer long-term protection, especially in vulnerable senescent populations, against both the 2003 epidemic strains and zoonotic strains that may yet emerge from animal reservoirs. We report the comprehensive investigation of SARS vaccine efficacy in young and senescent mice following homologous and heterologous challenge. METHODS AND FINDINGS: Using Venezuelan equine encephalitis virus replicon particles (VRP) expressing the 2003 epidemic Urbani SARS-CoV strain spike (S) glycoprotein (VRP-S) or the nucleocapsid (N) protein from the same strain (VRP-N), we demonstrate that VRP-S, but not VRP-N vaccines provide complete short- and long-term protection against homologous strain challenge in young and senescent mice. To test VRP vaccine efficacy against a heterologous SARS-CoV, we used phylogenetic analyses, synthetic biology, and reverse genetics to construct a chimeric virus (icGDO3-S) encoding a synthetic S glycoprotein gene of the most genetically divergent human strain, GDO3, which clusters among the zoonotic SARS-CoV. icGD03-S replicated efficiently in human airway epithelial cells and in the lungs of young and senescent mice, and was highly resistant to neutralization with antisera directed against the Urbani strain. Although VRP-S vaccines provided complete short-term protection against heterologous icGD03-S challenge in young mice, only limited protection was seen in vaccinated senescent animals. VRP-N vaccines not only failed to protect from homologous or heterologous challenge, but resulted in enhanced immunopathology with eosinophilic infiltrates within the lungs of SARS-CoV–challenged mice. VRP-N–induced pathology presented at day 4, peaked around day 7, and persisted through day 14, and was likely mediated by cellular immune responses. CONCLUSIONS: This study identifies gaps and challenges in vaccine design for controlling future SARS-CoV zoonosis, especially in vulnerable elderly populations. The availability of a SARS-CoV virus bearing heterologous S glycoproteins provides a robust challenge inoculum for evaluating vaccine efficacy against zoonotic strains, the most likely source of future outbreaks.

positive: Lack of cross-neutralization by SARS patient sera towards SARS-CoV-2 Despite initial findings indicating that SARS-CoV and SARS-CoV-2 are genetically related belonging to the same virus species and that the two viruses used the same entry receptor, angiotensin-converting enzyme 2 (ACE2), our data demonstrated that there is no detectable cross-neutralization by SARS patient sera against SARS-CoV-2. We also found that there are significant levels of neutralizing antibodies in recovered SARS patients 9-17 years after initial infection. These findings will be of significant use in guiding the development of serologic tests, formulating convalescent plasma therapy strategies, and assessing the longevity of protective immunity for SARS-related coronaviruses in general as well as vaccine efficacy.

positive: Pre-existing immunity to SARS-CoV-2: the knowns and unknowns T cell reactivity against SARS-CoV-2 was observed in unexposed people; however, the source and clinical relevance of the reactivity remains unknown. It is speculated that this reflects T cell memory to circulating ‘common cold’ coronaviruses. It will be important to define specificities of these T cells and assess their association with COVID-19 disease severity and vaccine responses.

positive: Host Immune Response and Immunobiology of Human SARS-CoV-2 Infection One of the most serious viral outbreaks of the decade, infecting humans, originated from the city of Wuhan, China, by the end of December 2019, has left the world shaken up. It is the successor infection of severe acute respiratory syndrome coronavirus (SARS-CoV) named as SARS-CoV-2 causing a disease called as COVID-19 (Coronavirus disease-19). Being one of the most severe diseases in terms of transmission, this disease agitates the immune system of an individual quite disturbingly which at times leads to death, which is why it has become the need of the hour to step forward to extensively involve in understanding the genetics, pathogenesis, and immunopathology of SARS-CoV-2 in order to design drugs to treat or to design a vaccine to prevent. In this chapter, we have tried to review and summarize the studies done so far to understand the host–pathogen relationship and the host immune response during COVID-19 infection. One of the recent developments regarding the understanding of SARS-CoV-2 infection is the mechanism of immune evasion involved during the pathogenesis and cytokine storm syndrome during infection in the patient against which a drug called as Hydroxychloroquine has been designed. Comprehensively, we have tried to give an immunological insight into the SARS-CoV-2 infection in order to understand the possible outcome for any therapeutic advancement.

positive: Persistent viral RNA positivity during the recovery period of a patient with SARS-CoV-2 infection As an emerging infectious disease, the clinical course and virological course of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection remain to be further investigated. In this case report, we described a case of SARS-CoV-2 infection with the clinical course for more than 2 months. This patient had recovered from pneumonia after treatment. The viral RNA of throat swabs became negative and the viral-specific antibodies were produced during the recovery period. However, the viral RNA reappeared and additionally persisted in throat swabs for more than 40 days. In addition, the viral RNA was detected in multiple types of specimens with extremely high titers in the saliva. In conclusion, these findings indicate that SARS-CoV-2 can cause a long clinical course. The coexistence of viral RNA and viral-specific antibodies may imply an immune evasion of SARS-CoV-2 from the host's immune system.

positive: Reverse vaccinology approach to design a novel multi-epitope vaccine candidate against COVID-19: an in silico study At present, novel Coronavirus (2019-nCoV, the causative agent of COVID-19) has caused worldwide social and economic disruption. The disturbing statistics of this infection promoted us to develop an effective vaccine candidate against the COVID-19. In this study, bioinformatics approaches were employed to design and introduce a novel multi-epitope vaccine against 2019-nCoV that can potentially trigger both CD(4+) and CD(8+) T-cell immune responses and investigated its biological activities by computational tools. Three known antigenic proteins (Nucleocapsid, ORF3a, and Membrane protein, hereafter called NOM) from the virus were selected and analyzed for prediction of the potential immunogenic B and T-cell epitopes and then validated using bioinformatics tools. Based on in silico analysis, we have constructed a multi-epitope vaccine candidate (NOM) with five rich-epitopes domain including highly scored T and B-cell epitopes. After predicting and evaluating of the third structure of the protein candidate, the best 3 D predicted model was applied for docking studies with Toll-like receptor 4 (TLR4) and HLA-A*11:01. In the next step, molecular dynamics (MD) simulation was used to evaluate the stability of the designed fusion protein with TLR4 and HLA-A*11:01 receptors. MD studies demonstrated that the NOM-TLR4 and NOM-HLA-A*11:01 docked models were stable during simulation time. In silico evaluation showed that the designed chimeric protein could simultaneously elicit humoral and cell-mediated immune responses. Communicated by Ramaswamy H. Sarma

positive: SARS-CoV-2 infection protects against rechallenge in rhesus macaques An understanding of protective immunity to SARS-CoV-2 is critical for vaccine and public health strategies aimed at ending the global COVID-19 pandemic. A key unanswered question is whether infection with SARS-CoV-2 results in protective immunity against re-exposure. We developed a rhesus macaque model of SARS-CoV-2 infection and observed that macaques had high viral loads in the upper and lower respiratory tract, humoral and cellular immune responses, and pathologic evidence of viral pneumonia. Following initial viral clearance, animals were rechallenged with SARS-CoV-2 and showed 5 log(10) reductions in median viral loads in bronchoalveolar lavage and nasal mucosa compared with primary infection. Anamnestic immune responses following rechallenge suggested that protection was mediated by immunologic control. These data show that SARS-CoV-2 infection induced protective immunity against re-exposure in nonhuman primates.

positive: A Genomic Survey of SARS-CoV-2 Reveals Multiple Introductions into Northern California without a Predominant Lineage The COVID-19 pandemic caused by the novel coronavirus SARS-CoV-2 has spread globally, resulting in >300,000 reported cases worldwide as of March 21st, 2020. Here we investigate the genetic diversity and genomic epidemiology of SARS-CoV-2 in Northern California using samples from returning travelers, cruise ship passengers, and cases of community transmission with unclear infection sources. Virus genomes were sampled from 29 patients diagnosed with COVID-19 infection from Feb 3rd through Mar 15th. Phylogenetic analyses revealed at least 8 different SARS-CoV-2 lineages, suggesting multiple independent introductions of the virus into the state. Virus genomes from passengers on two consecutive excursions of the Grand Princess cruise ship clustered with those from an established epidemic in Washington State, including the WA1 genome representing the first reported case in the United States on January 19th. We also detected evidence for presumptive transmission of SARS-CoV-2 lineages from one community to another. These findings suggest that cryptic transmission of SARS-CoV-2 in Northern California to date is characterized by multiple transmission chains that originate via distinct introductions from international and interstate travel, rather than widespread community transmission of a single predominant lineage. Rapid testing and contact tracing, social distancing, and travel restrictions are measures that will help to slow SARS-CoV-2 spread in California and other regions of the USA.

positive: Cellular immune status of coronavirus-infected neonatal calves Abstract A preliminary study was conducted to determine the cellular immune status of neonatal, colostrum-deprived calves following inoculation with either attenuated or virulent bovine coronavirus (BCV). Uninfected calves served as controls. To determine the intestinal and systemic cellular immune status, we performed MHC-restricted cytotoxic lymphocyte (CTL) assay on mesenteric lymphocytes, enumerated T cell subsets in peripheral blood lymphocytes, and examined histopathological alterations in mesenteric lymph nodes and gut-associated lymphoid tissue. Target cells for the CTL assay were autologous testicular cells and effector cells were mesenteric lymphocytes from calves infected with BCV. No appreciable specific lysis was observed in any group of calves indicating the absence of demonstrable CTL responses. The TC/TS population was severely depressed in the calf inoculated with the virulent virus but not in those inoculated with either the attenuated virus or placebo. The mesenteric lymph nodes and Peyer's patches of calves inoculated with the virulent virus showed severe depletion of lymphocytes. These calves developed intestinal antibody responses in the acute phase of infection (1 week after infection) but were immunosuppressed in the later stage of infection.

positive: Immune responses in influenza A virus and human coronavirus infections: an ongoing battle between the virus and host Respiratory viruses, especially influenza A viruses and coronaviruses such as MERS-CoV, represent continuing global threats to human health. Despite significant advances, much needs to be learned. Recent studies in virology and immunology have improved our understanding of the role of the immune system in protection and in the pathogenesis of these infections and of co-evolution of viruses and their hosts. These findings, together with sophisticated molecular structure analyses, omics tools and computer-based models, have helped delineate the interaction between respiratory viruses and the host immune system, which will facilitate the development of novel treatment strategies and vaccines with enhanced efficacy.

positive: Immune Responses to SARS-CoV, MERS-CoV and SARS-CoV-2 The world has given an outbreak alarm in the last two decades, with different members of the coronavirus family infecting people at different times. The spread of the SARS-CoV-2 virus, which last appeared in December 2019 in China and spread rapidly to all over the world, has led the scientific world to studies on these viruses. While scientists are trying to develop vaccines or drugs against the virus, the body's immune response to the virus is emerged the biggest guide. In this review, we aimed to provide a good view on immune strategies by comparing immunological responses to SARS-CoV-2 disease among other members of the family, SARS-CoV and MERS-CoV. In the near future, it may contribute to vaccine or drug studies to be developed on immune intervention.

positive: Neonatal immunity and immunisation in early age: lessons from veterinary medicine Abstract The objective of this paper is to review adaptive immunity of young animals using examples from my own experience and from the literature. Trials carried out by us with a modified live and inactivated canine parvovirus vaccine in newborn puppies provide evidence of the immune capacity of these puppies. With regard to transfer of immunity from mother to offspring, there is a role for transplacental and colostral immunity. Examples of passive protection of young animals against different infections include passive protection of kittens against the feline immunodeficiency virus. However, passive immunity, though very useful at an early age, varies in duration and makes implementation of standard vaccination schedules difficult. Other experiments demonstrate that, under certain conditions, it is possible to overcome residual maternally-derived antibodies and to induce post-vaccinal immunity.

positive: Artificial intelligence predicts the immunogenic landscape of SARS-CoV-2: toward universal blueprints for vaccine designs The global population is at present suffering from a pandemic of Coronavirus disease 2019 (COVID-19), caused by the novel coronavirus Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). The goals of this study were to use artificial intelligence (AI) to predict blueprints for designing universal vaccines against SARS-CoV-2, that contain a sufficiently broad repertoire of T-cell epitopes capable of providing coverage and protection across the global population. To help achieve these aims, we profiled the entire SARS-CoV-2 proteome across the most frequent 100 HLA-A, HLA-B and HLA-DR alleles in the human population, using host-infected cell surface antigen presentation and immunogenicity predictors from the NEC Immune Profiler suite of tools, and generated comprehensive epitope maps. We then used these epitope maps as input for a Monte Carlo simulation designed to identify statistically significant “epitope hotspot” regions in the virus that are most likely to be immunogenic across a broad spectrum of HLA types. We then removed epitope hotspots that shared significant homology with proteins in the human proteome to reduce the chance of inducing off-target autoimmune responses. We also analyzed the antigen presentation and immunogenic landscape of all the nonsynonymous mutations across 3400 different sequences of the virus, to identify a trend whereby SARS-COV-2 mutations are predicted to have reduced potential to be presented by host-infected cells, and consequently detected by the host immune system. A sequence conservation analysis then removed epitope hotspots that occurred in less-conserved regions of the viral proteome. Finally, we used a database of the HLA genotypes of approximately 22 000 individuals to develop a “digital twin” type simulation to model how effective different combinations of hotspots would work in a diverse human population, and used the approach to identify an optimal constellation of epitopes hotspots that could provide maximum coverage in the global population. By combining the antigen presentation to the infected-host cell surface and immunogenicity predictions of the NEC Immune Profiler with a robust Monte Carlo and digital twin simulation, we have managed to profile the entire SARS-CoV-2 proteome and identify a subset of epitope hotspots that could be harnessed in a vaccine formulation to provide a broad coverage across the global population.

positive: The expression and antigenicity of a truncated spike-nucleocapsid fusion protein of severe acute respiratory syndrome-associated coronavirus BACKGROUND: In the absence of effective drugs, controlling SARS relies on the rapid identification of cases and appropriate management of the close contacts, or effective vaccines for SARS. Therefore, developing specific and sensitive laboratory tests for SARS as well as effective vaccines are necessary for national authorities. RESULTS: Genes encoding truncated nucleocapsid (N) and spike (S) proteins of SARSCoV were cloned into the expression vector pQE30 and fusionally expressed in Escherichia coli M15. The fusion protein was analyzed for reactivity with SARS patients' sera and with anti-sera against the two human coronaviruses HCoV 229E and HCoV OC43 by ELISA, IFA and immunoblot assays. Furthermore, to evaluate the antigen-specific humoral antibody and T-cell responses in mice, the fusion protein was injected into 6-week-old BALB/c mice and a neutralization test as well as a T-cell analysis was performed. To evaluate the antiviral efficacy of immunization, BALB/c mice were challenged intranasally with SARSCoV at day 33 post injection and viral loads were determined by fluorescent quantitative RT-PCR. Serological results showed that the diagnostic sensitivity and specificity of the truncated S-N fusion protein derived the SARS virus were > 99% (457/460) and 100.00% (650/650), respectively. Furthermore there was no cross-reactivity with other two human coronaviruses. High titers of antibodies to SRASCoV appeared in the immunized mice and the neutralization test showed that antibodies to the fusion protein could inhibit SARSCoV. The T cell proliferation showed that the fusion protein could induce an antigen-specific T-cell response. Fluorescent quantitative RT-PCR showed that BALB/c mice challenged intranasally with SARSCoV at day 33 post injection were completely protected from virus replication. CONCLUSION: The truncated S-N fusion protein is a suitable immunodiagnostic antigen and vaccine candidate.

positive: Influence of immune aging on vaccine responses Impaired vaccine responses in older individuals are associated with alterations in both the quantity and quality of the T-cell compartment with age. As reviewed herein, the T-cell response to vaccination requires a fine balance between the generation of inflammatory effector T cells versus follicular helper T (TFH) cells that mediate high-affinity antibody production in tandem with the induction of long-lived memory cells for effective recall immunity. During aging, we find that this balance is tipped where T cells favor short-lived effector but not memory or TFH responses. Consistently, vaccine-induced antibodies commonly display a lower protective capacity. Mechanistically, multiple, potentially targetable, changes in T cells have been identified that contribute to these age-related defects, including posttranscription regulation, T-cell receptor signaling, and metabolic function. Although research into the induction of tissue-specific immunity by vaccines and with age is still limited, current mechanistic insights provide a framework for improved design of age-specific vaccination strategies that require further evaluation in a clinical setting.

positive: Dendritic Cell-Specific Antigen Delivery by Coronavirus Vaccine Vectors Induces Long-Lasting Protective Antiviral and Antitumor Immunity Efficient vaccination against infectious agents and tumors depends on specific antigen targeting to dendritic cells (DCs). We report here that biosafe coronavirus-based vaccine vectors facilitate delivery of multiple antigens and immunostimulatory cytokines to professional antigen-presenting cells in vitro and in vivo. Vaccine vectors based on heavily attenuated murine coronavirus genomes were generated to express epitopes from the lymphocytic choriomeningitis virus glycoprotein, or human Melan-A, in combination with the immunostimulatory cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF). These vectors selectively targeted DCs in vitro and in vivo resulting in vector-mediated antigen expression and efficient maturation of DCs. Single application of only low vector doses elicited strong and long-lasting cytotoxic T-cell responses, providing protective antiviral and antitumor immunity. Furthermore, human DCs transduced with Melan-A-recombinant human coronavirus 229E efficiently activated tumor-specific CD8(+) T cells. Taken together, this novel vaccine platform is well suited to deliver antigens and immunostimulatory cytokines to DCs and to initiate and maintain protective immunity.

positive: Restoration of leukomonocyte counts is associated with viral clearance in COVID-19 hospitalized patients Background: Viral clearance is one important indicator for the recovery of SARS-CoV-2 infected patients. Suboptimal T and B cell responses can delay viral clearance in MERS and SARS patients. The role of leukomonocytes in viral clearance of COVID-19 patients is not yet well defined.Methods: From January 26 to February 28, 2020, an observational study was launched at Zhongnan Hospital of Wuhan University, Wuhan, China. We enrolled 25 laboratory-confirmed COVID-19 patients, whose throat-swab specimens were tested positive for SARS-CoV-2 infection by qRT-PCR. We comprehensively analyzed clinical records, counts of lymphocyte subsets including CD3+, CD4+, CD8+ T cells, B cells and NK cells in the patients who successfully cleared SARS-CoV-2, and compared to those that failed to, after a standardized treatment of 8-14 days. Findings: In 25 enrolled COVID-19 patients, lymphopeniawas a common feature. After the treatment, 14 patients were tested negative for SARS-CoV-2. The patients that cleared the infection had restored the numbers of CD3+, CD4+, CD8+ T cellsand B cells as compared to the still viral RNA positive patients, while the recovered patients had a higher count of leukomonocytes. Conclusions: By comparison of leukomonocytes counts in COVID-19 patients at different stages of the disease, we found that CD3+, CD4+, CD8+ T cells and B cells appear to play important roles in viral clearance. The restoration of leukomonocytes counts from peripheral blood can be used as prognosis for the recovery of an COVID-19 infection. We propose that restoration of leukomonocytes counts can be added to the COVID-19 diagnostic guidanceas a criterion for releasing and discharging patients.

positive: Pathogenesis of severe acute respiratory syndrome Severe acute respiratory syndrome (SARS) is a zoonotic infectious disease caused by a novel coronavirus (CoV). The tissue tropism of SARS-CoV includes not only the lung, but also the gastrointestinal tract, kidney and liver. Angiotensin-converting enzyme 2 (ACE2), the C-type lectin CD209L (also known L-SIGN), and DC-SIGN bind SARS-CoV, but ACE2 appears to be the key functional receptor for the virus. There is a prominent innate immune response to SARS-CoV infection, including acute-phase proteins, chemokines, inflammatory cytokines and C-type lectins such as mannose-binding lectin, which plays a protective role against SARS. By contrast there may be a lack of type 1 interferon response. Moreover, lymphopenia with decreased numbers of CD4+ and CD8+ T cells is common during the acute phase. Convalescent patients have IgG-class neutralizing antibodies that recognize amino acids 441–700 of the spike protein (S protein) as the major epitope.

positive: Middle East Respiratory Syndrome Vaccine Candidates: Cautious Optimism Efforts towards developing a vaccine for Middle East respiratory syndrome coronavirus (MERS-CoV) have yielded promising results. Utilizing a variety of platforms, several vaccine approaches have shown efficacy in animal models and begun to enter clinical trials. In this review, we summarize the current progress towards a MERS-CoV vaccine and highlight potential roadblocks identified from previous attempts to generate coronavirus vaccines.

positive: If long-term suppression is not possible, how do we minimize mortality for COVID-19 and other emerging infectious disease outbreaks? If COVID-19 containment policies fail and social distancing measures cannot be sustained until vaccines becomes available, the next best approach is to use interventions that reduce mortality and prevent excess infections while allowing low-risk individuals to acquire immunity through natural infection until population level immunity is achieved. In such a situation, allowing some infections to occur in lower-risk groups might lead to an overall greater reduction in mortality than trying to protect everyone equally.

positive: SARS-CoV-2 and the testis: similarity with other viruses and routes of infection Since the start of the latest coronavirus (SARS-CoV-2) outbreak, the number of infected individuals and cases of coronavirus disease (COVID-19) has been increasing exponentially worldwide. Of interest is existing evidence that orchitis can develop due coronavirus infection. It is therefore not unreasonable to believe that SARS-CoV-2 could be transmitted by semen. Consequently, it is of paramount importance that individuals who could potentially be infected take all possible care to mitigate the likely risk of passing on the infection through sexual intercourse.

positive: Severe acute respiratory syndrome coronavirus spike protein expressed by attenuated vaccinia virus protectively immunizes mice. The spike protein (S), a membrane component of severe acute respiratory syndrome coronavirus (SARS-CoV) is anticipated to be an important component of candidate vaccines. We constructed recombinant forms of the highly attenuated modified vaccinia virus Ankara (MVA) containing the gene encoding full-length SARS-CoV S with and without a C-terminal epitope tag called MVA/S-HA and MVA/S, respectively. Cells infected with MVA/Sor MVA/S-HA synthesized a 200-kDa protein, which was recognized by antibody raised against a synthetic peptide of SARS-CoV S or the epitope tag in Western blot analyses. Further studies indicated that S was N-glycosylated and migrated in SDS polyacrylamide gels with an apparent mass of approximately 160 kDa after treatment with peptide N-glycosidase F. The acquisition of resistance to endoglycosidase H indicated trafficking of S to the medial Golgi compartment, and confocal microscopy showed that S was transported to the cell surface. Intranasal or intramuscular inoculations of BALB/c mice with MVA/S produced serum antibodies that recognized the SARS S in ELISA and neutralized SARS-CoV in vitro. Moreover, MVA/S administered by either route elicited protective immunity, as shown by reduced titers of SARS-CoV in the upper and lower respiratory tracts of mice after challenge. Passive transfer of serum from mice immunized with MVA/S to naïve mice also reduced the replication of SARS-CoV in the respiratory tract after challenge, demonstrating a role for antibody to S in protection. The attenuated nature of MVA and the ability of MVA/S to induce neutralizing antibody that protects mice support further development of this candidate vaccine.

positive: The perplexing question of trained immunity versus adaptive memory in COVID-19. The wide spectrum of symptoms observed in COVID-19 appears to defy explanation. Apart from geographic limitation to people with prior exposure to other coronaviruses and air pollutants, inflammatory comordidities and older ages are also among the main factors of susceptibility to severe illness. The unusual epidemiological data pointed out in children and African territories have revealed new insights in host-pathogen interplay with more focus on epigenetic regulation of cognitive compartments belonging to innate immunity. Should trained immunity be proven to be involved in timely immune responsiveness against SARS-CoV-2 and that adaptive memory could be detrimental, both treatment regimens and vaccine design will tremendously change accordingly with more focus on upper respiratory tissue innate immunity to subdue this threat underway. This article is protected by copyright. All rights reserved.

positive: IgA MAb blocks SARS-CoV-2 Spike-ACE2 interaction providing mucosal immunity COVID-19 caused by SARS-CoV-2 has become a global pandemic requiring the development of interventions for the prevention or treatment to curtail mortality and morbidity. No vaccine to boost mucosal immunity or as a therapeutic has yet been developed to SARS-CoV-2. In this study we discover and characterize a cross-reactive human IgA monoclonal antibody, MAb362. MAb362 binds to both SARS-CoV and SARS-CoV-2 spike proteins and competitively blocks hACE2 receptor binding, by completely overlapping the hACE2 structural binding epitope. Furthermore, MAb362 IgA neutralizes both pseudotyped SARS-CoV and SARS-CoV-2 in human epithelial cells expressing hACE2. SARS-CoV-2 specific IgA antibodies, such as MAb362, may provide effective immunity against SARS-CoV-2 by inducing mucosal immunity within the respiratory system, a potentially critical feature of an effective vaccine.

positive: Chapter 59 Respiratory Virus Vaccines Abstract This chapter reviews the main viral pathogens of the respiratory tract, the immune responses they induce, currently available vaccines, and vaccines that are in development to control them. The main viruses responsible for acute respiratory infection in people include respiratory syncytial, influenza, human parainfluenza, human metapneumo-, human rhino-, corona-, and adenoviruses. Licensed vaccines are available only for influenza virus, with vaccines against the other pathogens either in clinical trials or in preclinical stages of development. The majority of studies evaluating respiratory virus vaccines measure serum antibody responses, because, although both cellular and humoral responses contribute to the clearance of a primary infection, neutralizing antibodies are known to protect against secondary infection. Humoral responses can be readily detected after vaccination with inactivated or subunit vaccines; however, fewer individuals seroconvert after vaccination with live vaccines. Alternative immune mechanisms such as mucosal antibody responses are probably responsible for protection by live attenuated vaccines, and immune correlates of protection are under investigation.

positive: Immunity to transmissible gastroenteritis virus and porcine respiratory coronavirus infections in swine Abstract Despite the pioneering efforts to identify correlates of passive immunity to transmissible gastroenteritis virus (TGEV), effective vaccines for the control of TGE in suckling pigs have remained elusive. The initial concept of an enteromammary immunologic axis in monogastrics originated from studies of lactogenic immunity to TGEV in swine. These studies revealed that infection of pregnant swine with virulent TGEV stimulated high titers of SIgA antibodies in milk which correlated with protection of suckling pigs against TGE; parenteral or oral inoculation with live attenuated or killed TGEV vaccines induced mainly IgG antibodies in milk which generally provided poor protection to suckling pigs. The recent appearance of PRCV infections in swine and continuing studies of TGEV infections, present a unique model for further studies of mucosal immunity. Research using these viruses has increased our understanding of the various components of the common mucosal immune system and their interactions. Although the most important consideration in designing an effective vaccine for TGEV is the stimulation of GALT through intestinal virus replication, studies addressing the contribution of BALT to immunity to TGEV and PRCV may provide insights for alternative vaccine approaches. The mechanism by which exposure to PRCV elicits a variable degree of immunity to TGEV challenge is unknown. Virus replication in the gut or respiratory tract is a major factor affecting the magnitude of the immune response at the respective site and may be necessary for the recruitment of specific immune cells from other mucosal inductive sites, i.e., GALT to BALT and BALT to GALT migration. Further studies on the induction and immune regulation of specific responses to TGEV and PRCV that affect the distribution patterns of IgM-, IgG- and IgA-antibody-secreting cells (ASC) and T lymphocytes should provide valuable insights for optimizing vaccine regimens to elicit the highest mucosal immune responses and optimal protection against TGEV challenge.

positive: NKG2A and COVID-19: another brick in the wall

positive: Antibody responses to SARS-CoV-2 in COVID-19 patients: the perspective application of serological tests in clinical practice Background We aim to investigate the profile of acute antibody response in COVID-19 patients, and provide proposals for the usage of antibody test in clinical practice. Methods A multi-center cross-section study (285 patients) and a single-center follow-up study (63 patients) were performed to investigate the feature of acute antibody response to SARS-CoV-2. A cohort of 52 COVID-19 suspects and 64 close contacts were enrolled to evaluate the potentiality of the antibody test. Results The positive rate for IgG reached 100% around 20 days after symptoms onset. The median day of serocon-version for both lgG and IgM was 13 days after symptoms onset. Seroconversion of IgM occurred at the same time, or earlier, or later than that of IgG. IgG levels in 100% patients (19/19) entered a platform within 6 days after seroconversion. The criteria of IgG seroconversion and ≥ 4-fold increase in the IgG titers in sequential samples together diagnosed 82.9% (34/41) of the patients. Antibody test aided to confirm 4 patients with COVID-19 from 52 suspects who failed to be confirmed by RT-PCR and 7 patients from 148 close contacts with negative RT-PCR. Conclusion IgM and IgG should be detected simultaneously at the early phase of infection. The serological diagnosis criterion of seroconversion or ≥ 4-fold increase in the IgG titer is suitable for a majority of COVID-19 patients. Serologic test is helpful for the diagnosis of SARS-CoV-2 infection in suspects and close contacts.

positive: Recent Advances of Vaccine Adjuvants for Infectious Diseases Vaccines are the most effective and cost-efficient method for preventing diseases caused by infectious pathogens. Despite the great success of vaccines, development of safe and strong vaccines is still required for emerging new pathogens, re-emerging old pathogens, and in order to improve the inadequate protection conferred by existing vaccines. One of the most important strategies for the development of effective new vaccines is the selection and usage of a suitable adjuvant. Immunologic adjuvants are essential for enhancing vaccine potency by improvement of the humoral and/or cell-mediated immune response to vaccine antigens. Thus, formulation of vaccines with appropriate adjuvants is an attractive approach towards eliciting protective and long-lasting immunity in humans. However, only a limited number of adjuvants is licensed for human vaccines due to concerns about safety and toxicity. We summarize current knowledge about the potential benefits of adjuvants, the characteristics of adjuvants and the mechanisms of adjuvants in human vaccines. Adjuvants have diverse modes of action and should be selected for use on the basis of the type of immune response that is desired for a particular vaccine. Better understanding of current adjuvants will help exploring new adjuvant formulations and facilitate rational design of vaccines against infectious diseases.

positive: Characterization of anti-viral immunity in recovered individuals infected by SARS-CoV-2 The WHO has declared SARS-CoV-2 outbreak a public health emergency of international concern. However, to date, there was hardly any study in characterizing the immune responses, especially adaptive immune responses to SARS-CoV-2 infection. In this study, we collected blood from COVID-19 patients who have recently become virus-free and therefore were discharged, and analyzed their SARS-CoV-2-specific antibody and T cell responses. We observed SARS-CoV-2-specific humoral and cellular immunity in the patients. Both were detected in newly discharged patients, suggesting both participate in immune-mediated protection to viral infection. However, follow-up patients (2 weeks post discharge) exhibited high titers of IgG antibodies, but with low levels of virus-specific T cells, suggesting that they may enter a quiescent state. Our work has thus provided a basis for further analysis of protective immunity to SARS-CoV-2, and understanding the pathogenesis of COVID-19, especially in the severe cases. It has also implications in designing an effective vaccine to protect and treat SARS-CoV-2 infection.

positive: Development and use of the H strain of avian infectious bronchitis virus from the Netherlands as a vaccine: a review The H strain of infectious bronchitis (IB) was one of the earliest live attenuated IB vaccines to be developed and has continued to be used in most parts of the world for almost 50 years. It was developed for use at both the 52nd (H52) and 120th (H120) vaccine levels and, because of it ability to provide heterologous cross-protection against a number of IB viruses of different serotypes, has proved to be one of the most enduring live attenuated IB vaccines. In fact, the H120 vaccine is possibly the most widely used live attenuated IB vaccine globally to this day. The use of H52 has, however, declined with the introduction of safe and highly efficacious inactivated IB vaccines. This review documents the original studies to isolate and attenuate the H strain by serial embryo passage, and describes the early studies to demonstrate its efficacy in laboratory studies and under field conditions. The efficacy of the H vaccine in providing cross-protection against some of the many IB variants now reported worldwide is also discussed, and possible future vaccination strategies for IB considered.

positive: T cells found in coronavirus patients 'bode well' for long-term immunity.

positive: Trained immunity: a tool for reducing susceptibility and severity of SARS-CoV-2 infection Abstract SARS-CoV-2 infection is mild in the majority of individuals, but progresses into severe pneumonia in a small proportion of patients. The increased susceptibility to severe disease in the elderly and individuals with co-morbidities argues for an initial defect in anti-viral host defense mechanisms. Long-term boosting of innate immune responses, also termed ‘trained immunity’, by certain live vaccines (BCG, oral polio vaccine, measles) induces heterologous protection against infections, through epigenetic, transcriptional and functional reprogramming of innate immune cells. We propose that induction of trained immunity by whole microorganism vaccines may represent an important tool for reducing susceptibility and severity to SARS-CoV-2.

positive: Spike protein binding prediction with neutralizing antibodies of SARS-CoV-2 Coronavirus disease 2019 (COVID-19) is a new emerging human infectious disease caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2, also previously known as 2019-nCoV), originated in Wuhan seafood and animal market, China. Since December 2019, more than 69,000 cases of COVID-19 have been confirmed in China and quickly spreads to other counties. Currently, researchers put their best efforts to identify effective drugs for COVID-19. The neutralizing antibody, which binds to viral capsid in a manner that inhibits cellular entry of virus and uncoating of the genome, is the specific defense against viral invaders. In this study, we investigate to identify neutralizing antibodies that can bind to SARS-CoV-2 Sipke (S) protein and interfere with the interaction between viral S protein and a host receptor by bioinformatic methods. The sequence analysis of S protein showed two major differences in the RBD region of the SARS-CoV-2 S protein compared to SARS-CoV and SARS-CoV related bat viruses (btSARS-CoV). The insertion regions were close to interacting residues with the human ACE2 receptor. Epitope analysis of neutralizing antibodies revealed that SARS-CoV neutralizing antibodies used conformational epitopes, whereas MERS-CoV neutralizing antibodies used a common linear epitope region, which contributes to form the β-sheet structure in MERS-CoV S protein and deleted in SARS-CoV-2 S protein. To identify effective neutralizing antibodies for SARS-CoV-2, the binding affinities of neutralizing antibodies with SARS-CoV-2 S protein were predicted and compared by antibody-antigen docking simulation. The result showed that CR3022 neutralizing antibody from human may have higher binding affinity with SARS-CoV-2 S protein than SARS-CoV S protein. We also found that F26G19 and D12 mouse antibodies could bind to SARS-CoV S protein with high affinity. Our findings provide crucial clues towards the development of antigen diagnosis, therapeutic antibody, and the vaccine against SARS-CoV-2.

positive: Intervention Serology and Interaction Substitution: Modeling the Role of ‘Shield Immunity’ in Reducing COVID-19 Epidemic Spread The COVID-19 pandemic has precipitated a global crisis, with more than 690,000 confirmed cases and more than 33,000 confirmed deaths globally as of March 30, 2020 [1–4]. At present twOfficentral public health control strategies have emerged: mitigation and suppression (e.g, [5]). Both strategies focus on reducing new infections by reducing interactions (and both raise questions of sustainability and long-term tactics). Complementary to those approaches, here we develop and analyze an epidemiological intervention model that leverages serological tests [6, 7] to identify and deploy recovered individuals as focal points for sustaining safer interactions via interaction substitution, i.e., to develop what we term ‘shield immunity’ at the population scale. Recovered individuals, in the present context, represent those who have developed protective, antibodies to SARS-CoV-2 and are no longer shedding virus [8]. The objective of a shield immunity strategy is to help sustain the interactions necessary for the functioning of essential goods and services (including but not limited to tending to the elderly [9], hospital care, schools, and food supply) while decreasing the probability of transmission during such essential interactions. We show that a shield immunity approach may significantly reduce the length and reduce the overall burden of an outbreak, and can work synergistically with social distancing. The present model highlights the value of serological testing as part of intervention strategies, in addition to its well recognized roles in estimating prevalence [10, 11] and in the potential development of plasma-based therapies [12–15].

positive: Human immunopathogenesis of severe acute respiratory syndrome (SARS) Abstract Progressive immune-associated injury is a hallmark of severe acute respiratory syndrome (SARS). Viral evasion of innate immunity, hypercytokinemia and systemic immunopathology in the SARS coronavirus (SARS CoV) infected host have been suggested as possible mechanisms for the cause of severe pathology and morbidity in SARS patients. The molecular and cellular basis for how SARS CoV impacts the host immune system resulting in severe SARS, however, has not been elucidated. The variable clinical course of SARS may be the result of complex programs of host responses against the infectious agent. Therefore, the systematic analysis of innate and adaptive immune responses to SARS CoV is imperative in building as complete an immunological model as possible of host immunity and inflammatory responses during illness. Here we review recent advances in SARS immunopathogenesis research and present a summary of our findings regarding host responses in SARS patients. We contend that dysregulated type I and II interferon (IFN) responses during SARS may culminate in a failure of the switch from hyper-innate immunity to protective adaptive immune responses in the human host.

positive: Antibody responses to SARS-CoV-2 in patients of novel coronavirus disease 2019 BACKGROUND: The novel coronavirus SARS-CoV-2 is a newly emerging virus. The antibody response in infected patient remains largely unknown, and the clinical values of antibody testing have not been fully demonstrated. METHODS: A total of 173 patients with SARS-CoV-2 infection were enrolled. Their serial plasma samples (n=535) collected during the hospitalization were tested for total antibodies (Ab), IgM and IgG against SARS-CoV-2. The dynamics of antibodies with the disease progress was analyzed. RESULTS: Among 173 patients, the seroconversion rate for Ab, IgM and IgG was 93.1%, 82.7% and 64.7%, respectively. The reason for the negative antibody findings in 12 patients might due to the lack of blood samples at the later stage of illness. The median seroconversion time for Ab, IgM and then IgG were day-11, day-12 and day-14, separately. The presence of antibodies was <40% among patients within 1-week since onset, and rapidly increased to 100.0% (Ab), 94.3% (IgM) and 79.8% (IgG) since day-15 after onset. In contrast, RNA detectability decreased from 66.7% (58/87) in samples collected before day-7 to 45.5% (25/55) during day 15-39. Combining RNA and antibody detections significantly improved the sensitivity of pathogenic diagnosis for COVID-19 (p<0.001), even in early phase of 1-week since onset (p=0.007). Moreover, a higher titer of Ab was independently associated with a worse clinical classification (p=0.006). CONCLUSIONS: The antibody detection offers vital clinical information during the course of SARS-CoV-2 infection. The findings provide strong empirical support for the routine application of serological testing in the diagnosis and management of COVID-19 patients.

positive: Characterization of spike glycoprotein of SARS-CoV-2 on virus entry and its immune cross-reactivity with SARS-CoV Since 2002, beta coronaviruses (CoV) have caused three zoonotic outbreaks, SARS-CoV in 2002-2003, MERS-CoV in 2012, and the newly emerged SARS-CoV-2 in late 2019. However, little is currently known about the biology of SARS-CoV-2. Here, using SARS-CoV-2 S protein pseudovirus system, we confirm that human angiotensin converting enzyme 2 (hACE2) is the receptor for SARS-CoV-2, find that SARS-CoV-2 enters 293/hACE2 cells mainly through endocytosis, that PIKfyve, TPC2, and cathepsin L are critical for entry, and that SARS-CoV-2 S protein is less stable than SARS-CoV S. Polyclonal anti-SARS S1 antibodies T62 inhibit entry of SARS-CoV S but not SARS-CoV-2 S pseudovirions. Further studies using recovered SARS and COVID-19 patients' sera show limited cross-neutralization, suggesting that recovery from one infection might not protect against the other. Our results present potential targets for development of drugs and vaccines for SARS-CoV-2.

positive: The Novel Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Directly Decimates Human Spleens and Lymph Nodes While lymphocytopenia is a common characteristic of patients infected by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the mechanisms responsible for this depletion are unclear. Through careful inspection of the spleens and lymph nodes (LNs) from six cases with postmortem examinations, we observed that SARS-CoV-2 could directly infect secondary lymphoid organs to induce cell death. Immunohistochemistry demonstrated ACE2 (angiotensin-converting enzyme 2), the potential receptor of SARS-CoV-2, expresses on tissue-resident CD169+ macrophages in spleens and LNs. Immunofluorescent staining confirmed that viral nucleocaspid protein (NP) can be found in ACE2+ cells, CD169+ macrophages, but not in CD3+ T cells or B220+ B cells in spleens and LNs. SARS-CoV-2 infection induces severe tissue damage including lymph follicle depletion, splenic nodule atrophy, histiocyte hyperplasia and lymphocyte reductions. Moreover, in situ TUNEL staining illustrated that viral infection leads to severe lymphocyte apoptosis, which might be mediated by viral antigens inducing Fas upregulation. Furthermore, SARS-CoV-2 also triggers macrophages to produce IL-6, a proinflammatory cytokine that directly promotes lymphocyte necrosis. Collectively, these results demonstrate that SARS-CoV-2 directly neutralizes human spleens and LNs through infecting tissue- resident CD169+ macrophages.

positive: SARS-CoV-2 infection-induced immune responses: Friends or foes? Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an emerging coronavirus that belongs to the ß-genus, causing the outbreak of coronavirus disease 19 (COVID-19). SARS-CoV-2 infection can stimulate a pronounced immune response in the host, which embodies in the decrease of lymphocytes and aberrant increase of cytokines in COVID-19 patients. SARS-CoV-2 RNA and proteins interact with various pattern recognition receptors that switch on antiviral immune responses to regulate viral replication and spreading within the host in vivo. However, overactive and impaired immune responses also cause immune damage and subsequent tissue inflammation. This article focuses on the dual roles of immune system during SARS-CoV-2 infection, providing a theoretical basic for identifying therapeutic targets in a situation with an unfavourable immune reaction.

positive: Immunotherapies for COVID-19: restoring the immunity could be the priority

positive: Serological Approaches for COVID-19: Epidemiologic Perspective on Surveillance and Control Since December 2019, the novel coronavirus, SARS-CoV-2, has garnered global attention due to its rapid transmission, which has infected more than two million people worldwide. Early detection of SARS-CoV-2 is one of the crucial interventions to control virus spread and dissemination. Molecular assays have been the gold standard to directly detect for the presence of viral genetic material in infected individuals. However, insufficient viral RNA at the point of detection may lead to false negative results. As such, it is important to also employ immune-based assays to determine one's exposure to SARS-CoV-2, as well as to assist in the surveillance of individuals with prior exposure to SARS-CoV-2. Within a span of 4 months, extensive studies have been done to develop serological systems to characterize the antibody profiles, as well as to identify and generate potentially neutralizing antibodies during SARS-CoV-2 infection. The vast diversity of novel findings has added value to coronavirus research, and a strategic consolidation is crucial to encompass the latest advances and developments. This review aims to provide a concise yet extensive collation of current immunoassays for SARS-CoV-2, while discussing the strengths, limitations and applications of antibody detection in SARS-CoV-2 research and control.

positive: Coronavirus Papain-like Proteases Negatively Regulate Antiviral Innate Immune Response through Disruption of STING-Mediated Signaling Viruses have evolved elaborate mechanisms to evade or inactivate the complex system of sensors and signaling molecules that make up the host innate immune response. Here we show that human coronavirus (HCoV) NL63 and severe acute respiratory syndrome (SARS) CoV papain-like proteases (PLP) antagonize innate immune signaling mediated by STING (stimulator of interferon genes, also known as MITA/ERIS/MYPS). STING resides in the endoplasmic reticulum and upon activation, forms dimers which assemble with MAVS, TBK-1 and IKKε, leading to IRF-3 activation and subsequent induction of interferon (IFN). We found that expression of the membrane anchored PLP domain from human HCoV-NL63 (PLP2-TM) or SARS-CoV (PLpro-TM) inhibits STING-mediated activation of IRF-3 nuclear translocation and induction of IRF-3 dependent promoters. Both catalytically active and inactive forms of CoV PLPs co-immunoprecipitated with STING, and viral replicase proteins co-localize with STING in HCoV-NL63-infected cells. Ectopic expression of catalytically active PLP2-TM blocks STING dimer formation and negatively regulates assembly of STING-MAVS-TBK1/IKKε complexes required for activation of IRF-3. STING dimerization was also substantially reduced in cells infected with SARS-CoV. Furthermore, the level of ubiquitinated forms of STING, RIG-I, TBK1 and IRF-3 are reduced in cells expressing wild type or catalytic mutants of PLP2-TM, likely contributing to disruption of signaling required for IFN induction. These results describe a new mechanism used by CoVs in which CoV PLPs negatively regulate antiviral defenses by disrupting the STING-mediated IFN induction.

positive: Complex Immune Dysregulation in COVID-19 Patients with Severe Respiratory Failure Summary Proper management of COVID-19 mandates better understanding of disease pathogenesis. The sudden clinical deterioration 7–8 days after initial symptom onset suggests that severe respiratory failure (SRF) in COVID-19 is driven by a unique pattern of immune dysfunction. We studied immune responses of 54 COVID-19 patients, 28 of whom had SRF. All patients with SRF displayed either macrophage activation syndrome (MAS) or very low human leukocyte antigen D related (HLA-DR) expression accompanied by profound depletion of CD4 lymphocytes, CD19 lymphocytes, and natural killer (NK) cells. Tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) production by circulating monocytes was sustained, a pattern distinct from bacterial sepsis or influenza. SARS-CoV-2 patient plasma inhibited HLA-DR expression, and this was partially restored by the IL-6 blocker Tocilizumab; off-label Tocilizumab treatment of patients was accompanied by increase in circulating lymphocytes. Thus, the unique pattern of immune dysregulation in severe COVID-19 is characterized by IL-6-mediated low HLA-DR expression and lymphopenia, associated with sustained cytokine production and hyper-inflammation.

positive: Epitope-based peptide vaccines predicted against novel coronavirus disease caused by SARS-CoV-2 The outbreak of the 2019 novel coronavirus (SARS-CoV-2) has infected thousands of people with a large number of deaths across 26 countries. The sudden appearance of the virus leads to the limited existing therapies for SARS-CoV-2. Therefore, vaccines and antiviral medicines are in desperate need. This study took immune-informatics approaches to identify B- and T-cell epitopes for surface glycoprotein (S) of SARS-CoV-2, followed by estimating their antigenicity and interactions with the human leukocyte antigen (HLA) alleles. We identified four B cell epitopes, two MHC class-I and nine MHC class-II binding T-cell epitopes, which showed highly antigenic features. Allergenicity, toxicity and physiochemical properties analysis confirmed the specificity and selectivity of epitopes. The stability and safety of epitopes were confirmed by digestion analysis. No mutations were observed in all the selected B- and T-cell epitopes across all isolates from different locations worldwide. Epitopes were thus identified and some of them can be potential candidates for vaccine development.

positive: The innate immune system: fighting on the front lines or fanning the flames of COVID-19? Abstract The coronavirus disease 2019 (COVID-19) pandemic caused by SARS-CoV-2 has had devastating global impacts and will continue to have dramatic effects on public health for years to come. A better understanding of the immune response to SARS-CoV-2 will be critical for the application and development of therapeutics. The degree to which the innate immune response confers protection or induces pathogenesis through a dysregulated immune response remains unclear. In this review, we discuss what is known about the role of the innate immune system during SARS-CoV-2 infection, suggest directions for future studies, and evaluate proposed COVID-19 immunomodulating therapeutics.

positive: Host Factors Affecting Generation of Immunity Against Porcine Epidemic Diarrhea Virus in Pregnant and Lactating Swine and Passive Protection of Neonates Porcine epidemic diarrhea virus (PEDV) is a highly virulent re-emerging enteric coronavirus that causes acute diarrhea, dehydration, and up to 100% mortality in neonatal suckling piglets. Despite this, a safe and effective PEDV vaccine against highly virulent strains is unavailable, making PEDV prevention and control challenging. Lactogenic immunity induced via the gut-mammary gland-secretory IgA (sIgA) axis, remains the most promising and effective way to protect suckling piglets from PEDV. Therefore, a successful PEDV vaccine must induce protective maternal IgA antibodies that passively transfer into colostrum and milk. Identifying variables that influence lymphocyte migration and IgA secretion during gestation and lactation is imperative for designing maternal immunization strategies that generate the highest amount of lactogenic immune protection against PEDV in suckling piglets. Because pregnancy-associated immune alterations influence viral pathogenesis and adaptive immune responses in many different species, a better understanding of host immune responses to PEDV in pregnant swine may translate into improved maternal immunization strategies against enteric pathogens for multiple species. In this review, we discuss the role of host factors during pregnancy on antiviral immunity and their implications for generating protective lactogenic immunity in suckling neonates.

positive: Immune cell profiling of COVID-19 patients in the recovery stage by single-cell sequencing COVID-19, caused by SARS-CoV-2, has recently affected over 1,200,000 people and killed more than 60,000. The key immune cell subsets change and their states during the course of COVID-19 remain unclear. We sought to comprehensively characterize the transcriptional changes in peripheral blood mononuclear cells during the recovery stage of COVID-19 by single-cell RNA sequencing technique. It was found that T cells decreased remarkably, whereas monocytes increased in patients in the early recovery stage (ERS) of COVID-19. There was an increased ratio of classical CD14(++) monocytes with high inflammatory gene expression as well as a greater abundance of CD14(++)IL1β(+) monocytes in the ERS. CD4(+) T cells and CD8(+) T cells decreased significantly and expressed high levels of inflammatory genes in the ERS. Among the B cells, the plasma cells increased remarkably, whereas the naïve B cells decreased. Several novel B cell-receptor (BCR) changes were identified, such as IGHV3-23 and IGHV3-7, and isotypes (IGHV3-15, IGHV3-30, and IGKV3-11) previously used for virus vaccine development were confirmed. The strongest pairing frequencies, IGHV3-23-IGHJ4, indicated a monoclonal state associated with SARS-CoV-2 specificity, which had not been reported yet. Furthermore, integrated analysis predicted that IL-1β and M-CSF may be novel candidate target genes for inflammatory storm and that TNFSF13, IL-18, IL-2, and IL-4 may be beneficial for the recovery of COVID-19 patients. Our study provides the first evidence of an inflammatory immune signature in the ERS, suggesting COVID-19 patients are still vulnerable after hospital discharge. Identification of novel BCR signaling may lead to the development of vaccines and antibodies for the treatment of COVID-19.

positive: Vaccines for the prevention against the threat of MERS-CoV First identified in 2012, Middle East respiratory syndrome (MERS) coronavirus (MERS-CoV) is listed as a new Category C Priority Pathogen. While the high mortality of MERS-CoV infection is further intensified by potential human-to-human transmissibility, no MERS vaccines are available for human use. This review explains immune responses resulting from MERS-CoV infection, describes MERS vaccine criteria, and presents available small animal models to evaluate the efficacy of MERS vaccines. Current advances in vaccine development are summarized, focusing on specific applications and limitations of each vaccine category. Taken together, this review provides valuable guidelines toward the development of an effective and safe MERS vaccine. This article is written for a Special Focus Issue of Expert Review of Vaccines on “Vaccines for Biodefence”.

positive: Structure, Immunopathogenesis and Vaccines Against SARS Coronavirus A new disease, severe atypical respiratory syndrome (SARS), emerged in China in late 2002 and developed into the first epidemic of the 21st century. The disease was caused by an unknown animal coronavirus (CoV) that had crossed the species barrier through close contact of humans with infected animals, and was identified as the etiological agent for SARS. This new CoV not only became readily transmissible between humans but also was also more pathogenic. The disease spread across the world rapidly due to the air travel, and infected 8096 people and caused 774 deaths in 26 countries on 5 continents. The disease is characterized by flu-like symptoms, including high fever, malaise, cough, diarrhea, and infiltrates visible on chest radiography. The overall mortality was about 10%, but varied profoundly with age; the course of disease seemed to be milder in the pediatric age group and resulted rarely in a fatal outcome, but the mortality in the elderly was as high as 50%. Aggressive quarantine measures taken by the health authorities have successfully contained and terminated the disease transmission. As a result there are no SARS cases recorded recently. Nevertheless there is a possibility that the disease may emerge in the population with high vigor. Significant progress has been made in understanding the disease biology, pathogenesis, development of animal models, and design and evaluation of different vaccines, and these are the focus of this chapter.

positive: Discrete SIRIR modelling using empirical infection data shows that SARS-CoV-2 infection provides short-term immunity The novel coronavirus SARS-CoV-2, which causes the COVID-19 disease, is now a global pandemic. Since December 2019, it has infected millions of people, caused the deaths of hundreds of thousands, and resulted in incalculable social and economic damage. Understanding the infectivity and transmission dynamics of the virus is essential for understanding how best to reduce mortality whilst ensuring minimal social restrictions to the lives of the general population. Anecdotal evidence is available, but detailed studies have not yet revealed whether infection with the virus results in immunity. In this work, we have extended the generic SIR framework to analyse empirical infection and fatality data from different regions to investigate the reinfection frequency of the disease. Our model predicts that cases of reinfection should have been observed by now if primary SARS-CoV-2 infection did not protect from subsequent exposure in the short term, however, no such cases have been documented. This work, therefore, provides a useful insight for serological testing strategies, lockdown easing and vaccine design.

positive: Intrafamilial Exposure to SARS-CoV-2 Induces Cellular Immune Response without Seroconversion Background. In the background of the current COVID-19 pandemic, serological tests are being used to assess past infection and immunity against SARS-CoV-2. This knowledge is paramount to determine the transmission dynamics of SARS-CoV-2 through the post pandemic period. Several individuals belonging to households with an index COVID-19 patient, reported symptoms of COVID-19 but discrepant serology results. Methods. Here we investigated the humoral and cellular immune responses against SARS-CoV-2 in seven families, including nine index patients and eight contacts, who had evidence of serological discordances within the households. Ten unexposed healthy donors were enrolled as controls. Results. All index patients recovered from a mild COVID-19. They all developed anti-SARS-CoV-2 antibodies and a significant T cell response detectable up to 69 days after symptom onset. Six of the eight contacts reported COVID-19 symptoms within 1 to 7 days after the index patients but all were SARS-CoV-2 seronegative. Six out of eight contacts developed a SARS-CoV-2-specific T cell response against structural and/or accessory proteins that lasts up to 80 days post symptom onset suggesting a past SARS-CoV-2 infection. Conclusion. Exposure to SARS-CoV-2 can induce virus-specific T cell responses without seroconversion. T cell responses may be more sensitive indicators of SARS-Co-V-2 exposure than antibodies. Our results indicate that epidemiological data relying only on the detection of SARS-CoV-2 antibodies may lead to a substantial underestimation of prior exposure to the virus

positive: Children's vaccines do not induce cross reactivity against SARS-CoV. In contrast with adults, children infected by severe acute respiratory syndrome-corona virus (SARS-CoV) develop milder clinical symptoms. Because of this, it is speculated that children vaccinated with various childhood vaccines might develop cross immunity against SARS-CoV. Antisera and T cells from mice immunised with various vaccines were used to determine whether they developed cross reactivity against SARS-CoV. The results showed no marked cross reactivity against SARS-CoV, which implies that the reduced symptoms among children infected by SARS-CoV may be caused by other factors.

positive: Comparative Genomic Analysis of Rapidly Evolving SARS-CoV-2 Viruses Reveal Mosaic Pattern of Phylogeographical Distribution The Coronavirus Disease-2019 (COVID-19) that started in Wuhan, China in December 2019 has spread worldwide emerging as a global pandemic. The severe respiratory pneumonia caused by the novel SARS-CoV-2 has so far claimed more than 60,000 lives and has impacted human lives worldwide. However, as the novel SARS-CoV-2 displays high transmission rates, their underlying genomic severity is required to be fully understood. We studied the complete genomes of 95 SARS-CoV-2 strains from different geographical regions worldwide to uncover the pattern of the spread of the virus. We show that there is no direct transmission pattern of the virus among neighboring countries suggesting that the outbreak is a result of travel of infected humans to different countries. We revealed unique single nucleotide polymorphisms (SNPs) in nsp13-16 (ORF1b polyprotein) and S-Protein within 10 viral isolates from the USA. These viral proteins are involved in RNA replication, indicating highly evolved viral strains circulating in the population of USA than other countries. Furthermore, we found an amino acid addition in nsp16 (mRNA cap-1 methyltransferase) of the USA isolate (MT188341) leading to shift in amino acid frame from position 2540 onwards. Through the construction of SARS-CoV-2-human interactome, we further revealed that multiple host proteins (PHB, PPP1CA, TGF-β, SOCS3, STAT3, JAK1/2, SMAD3, BCL2, CAV1 & SPECC1) are manipulated by the viral proteins (nsp2, PL-PRO, N-protein, ORF7a, M-S-ORF3a complex, nsp7-nsp8-nsp9-RdRp complex) for mediating host immune evasion. Thus, the replicative machinery of SARS-CoV-2 is fast evolving to evade host challenges which need to be considered for developing effective treatment strategies.

positive: COVID-19 is milder in children possibly due to cross-immunity

positive: Interferon and cytokine responses to SARS-coronavirus infection Abstract The sudden emergence of severe acute respiratory syndrome (SARS) has boosted research on innate immune responses to coronaviruses. It is now well established that the causative agent, a newly identified coronavirus termed SARS-CoV, employs multiple passive and active mechanisms to avoid induction of the antiviral type I interferons in tissue cells. By contrast, chemokines such as IP-10 or IL-8 are strongly upregulated. The imbalance in the IFN response is thought to contribute to the establishment of viremia early in infection, whereas the production of chemokines by infected organs may be responsible for (i) massive immune cell infiltrations found in the lungs of SARS victims, and (ii) the dysregulation of adaptive immunity. Here, we will review the most recent findings on the interaction of SARS-CoV and related Coronaviridae members with the type I interferon and cytokine responses and discuss implications for pathogenesis and therapy.

positive: Rapid generation of neutralizing antibody responses in COVID-19 patients Summary SARS-CoV-2, the virus responsible for COVID-19, is causing a devastating global pandemic and there is a pressing need to understand the development, specificity, and neutralizing potency of humoral immune responses during acute infection. We report a cross-sectional study of antibody responses to the receptor-binding domain (RBD) of the spike protein and virus neutralization activity in a cohort of 44 hospitalized COVID-19 patients. RBD-specific IgG responses are detectable in all patients 6 days after PCR confirmation. Isotype switching to IgG occurs rapidly, primarily to IgG1 and IgG3. Using a clinical SARS-CoV-2 isolate, neutralizing antibody titers are detectable in all patients by 6 days after PCR confirmation and correlate with RBD-specific binding IgG titers. The RBD-specific binding data were further validated in a clinical setting with 231 PCR-confirmed COVID-19 patient samples. These findings have implications for understanding protective immunity against SARS-CoV-2, therapeutic use of immune plasma, and development of much-needed vaccines.

positive: VIROLOGIC STUDIES OF ACUTE RESPIRATORY DISEASE IN YOUNG ADULTS: V. CORONAVIRUS 229E INFECTIONS DURING SIX YEARS OF SURVEILLANCE Hamre, D. and M. Beem (DepL Pediatrics, Univ. of Chicago, Chicago, III. 60637). Virologic studies of acute respiratory disease in young adults. V. Coronavirus 229E infections during six years of surveillance. Am J Epidemiol 96: 94–106, 1972.—In a surveillance study of acute respiratory disease in medical students that spanned six consecutive seasons between 1961 and 1968 and encompassed 937 student years of observation, infection with coronavirus 229E was identified by virus isolation and serologic studies. Virus isolation identified 12 infections, 8 in one season, 4 in another. Complement fixing (CF) antibody titer rises identified 133 infections that occurred in all six seasons of surveillance, involving from 15 to 35% of students in three seasons of “high” prevalence, and 1 to 5% in intervening seasons of “low” prevalence. Infection occurred in a winter-spring seasonal pattern and was associated with acute respiratory illness that was not clinically distinctive. Neutralizing antibody to 229E was commonly present in the sera of the students. The level of this did not appear to influence the occurrence of, or likelihood of illness with, reinfection as judged by CF seroconversion; however, the frequency of significant rise in neutralizing antibody titer with reinfection was inversely related to pre-infection levels of this antibody. Infection with other common respiratory viruses did not stimulate significant CF or neutralizing antibody titer rises to 229E.

positive: Intranasal vaccination of recombinant adeno-associated virus encoding receptor-binding domain of severe acute respiratory syndrome coronavirus (SARS-CoV) spike protein induces strong mucosal immune responses and provides long-term protection against SARS-CoV infection. We have previously reported that a subunit protein vaccine based on the receptor-binding domain (RBD) of severe acute respiratory syndrome coronavirus (SARS-CoV) spike protein and a recombinant adeno-associated virus (rAAV)-based RBD (RBD-rAAV) vaccine could induce highly potent neutralizing Ab responses in immunized animals. In this study, systemic, mucosal, and cellular immune responses and long-term protective immunity induced by RBD-rAAV were further characterized in a BALB/c mouse model, with comparison of the i.m. and intranasal (i.n.) routes of administration. Our results demonstrated that: 1) the i.n. vaccination induced a systemic humoral immune response of comparable strength and shorter duration than the i.m. vaccination, but the local humoral immune response was much stronger; 2) the i.n. vaccination elicited stronger systemic and local specific cytotoxic T cell responses than the i.m. vaccination, as evidenced by higher prevalence of IL-2 and/or IFN-gamma-producing CD3+/CD8+ T cells in both lungs and spleen; 3) the i.n. vaccination induced similar protection as the i.m. vaccination against SARS-CoV challenge in mice; 4) higher titers of mucosal IgA and serum-neutralizing Ab were associated with lower viral load and less pulmonary pathological damage, while no Ab-mediated disease enhancement effect was observed; and 5) the vaccination could provide long-term protection against SARS-CoV infection. Taken together, our findings suggest that RBD-rAAV can be further developed into a vaccine candidate for prevention of SARS and that i.n. vaccination may be the preferred route of administration due to its ability to induce SARS-CoV-specific systemic and mucosal immune responses and its better safety profile.

positive: Immune Status of COVID-19 Patients with Reference to SARS and MERS During this global pandemic of COVID-19 infection, it became well known that morbidity and mortality is especially high at the extreme of life especially in certain racial or ethnic groups like Americans and Africans This is presumed due to low immunity associated with other comorbid conditions like diabetes, hypertension, cardiovascular disease, obesity and metabolic syndrome But the information available on the immune status of COVID-19 patients is limited Attempts must be made to enhance our understanding of the immune status of COVID-19 patients by revisiting our knowledge on the immune mechanisms of already known coronaviruses such as SARS-CoV and MERS-CoV Early elevation of the serum levels of pro-inflammatory cytokines observed in SARS and MERS infection suggests a possible same type of cytokine storm-mediated lung damage in COVID-19 patients too Dysregulation of interferon-1 response and downstream cascade in initial innate immune response at virus entry point has been related to lethal pneumonia in COVID-19 patients Adaptive response of increased CD8+ levels in COVID-19 patients seems to be useful in mild cases where it causes deteriorating effects in progressed severe disease patients resulting in destruction of type 2 pneumocytes hence inability to regenerate the alveolar epithelium A phenomenon called cytokine storm activates violent immunological reactions in the lung tissue resulting in ARDS followed by multiple organ system damages in COVID-19 patients Several immune evading mechanisms are thought to be employed by severe respiratory syndrome virus-2 (SARS-CoV-2) that might have resulted in its extremely increased contagiousness probably related with its frequent RNA mutations Failure to develop adequate virus limiting immune reactions by some cured patients warrant monitoring of all recovered patients This rapid mini review is aimed to enhance our knowledge of the immune status of COVID-19 infected patients with reference to SARS-CoV and MERS-CoV

positive: CD8 T cell responses to viral infections in sequence Our current understanding of virus‐specific T cell responses has been shaped by model systems with mice, where naive animals are infected with a single viral pathogen. Paradigms derived from such models, however, may not always be applicable to a natural setting, where a host is exposed to numerous pathogens over its lifetime. Accumulating data in animal models and with some human diseases indicate that a host's prior history of infections can impact the specificity of future CD8 T cell responses, even to unrelated viruses. This can have both beneficial and detrimental consequences for the host, including altered clearance of virus, distinct forms of immunopathology, and substantial changes in the pool of memory T cells. Here we will describe the characteristics of CD8 T cells and the dynamics of their response to heterologous viral infections in sequence.

positive: Projecting the transmission dynamics of SARS-CoV-2 through the post-pandemic period There is an urgent need to project how transmission of the novel betacoronavirus SARS-CoV-2 will unfold in coming years. These dynamics will depend on seasonality, the duration of immunity, and the strength of cross-immunity to/from the other human coronaviruses. Using data from the United States, we measured how these factors affect transmission of human betacoronaviruses HCoV-OC43 and HCoV-HKU1. We then built a mathematical model to simulate transmission of SARS-CoV-2 through the year 2025. We project that recurrent wintertime outbreaks of SARS-CoV-2 will probably occur after an initial pandemic wave. We summarize the full range of plausible transmission scenarios and identify key data still needed to distinguish between them, most importantly longitudinal serological studies to determine the duration of immunity to SARS-CoV-2.

positive: Projecting the transmission dynamics of SARS-CoV-2 through the postpandemic period It is urgent to understand the future of severe acute respiratory syndrome–coronavirus 2 (SARS-CoV-2) transmission. We used estimates of seasonality, immunity, and cross-immunity for betacoronaviruses OC43 and HKU1 from time series data from the USA to inform a model of SARS-CoV-2 transmission. We projected that recurrent wintertime outbreaks of SARS-CoV-2 will probably occur after the initial, most severe pandemic wave. Absent other interventions, a key metric for the success of social distancing is whether critical care capacities are exceeded. To avoid this, prolonged or intermittent social distancing may be necessary into 2022. Additional interventions, including expanded critical care capacity and an effective therapeutic, would improve the success of intermittent distancing and hasten the acquisition of herd immunity. Longitudinal serological studies are urgently needed to determine the extent and duration of immunity to SARS-CoV-2. Even in the event of apparent elimination, SARS-CoV-2 surveillance should be maintained since a resurgence in contagion could be possible as late as 2024.

positive: Development of an inactivated vaccine candidate for SARS-CoV-2 The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome–coronavirus 2 (SARS-CoV-2) has resulted in an unprecedented public health crisis. There are currently no SARS-CoV-2-specific treatments or vaccines available due to the novelty of the virus. Hence, rapid development of effective vaccines against SARS-CoV-2 are urgently needed. Here we developed a pilot-scale production of a purified inactivated SARS-CoV-2 virus vaccine candidate (PiCoVacc), which induced SARS-CoV-2-specific neutralizing antibodies in mice, rats and non-human primates. These antibodies neutralized 10 representative SARS-CoV-2 strains, suggesting a possible broader neutralizing ability against SARS-CoV-2 strains. Three immunizations using two different doses (3 μg or 6 μg per dose) provided partial or complete protection in macaques against SARS-CoV-2 challenge, respectively, without observable antibody-dependent enhancement of infection. These data support clinical development of SARS-CoV-2 vaccines for humans.

positive: SARS-CoV-2 and COVID-19 in older adults: what we may expect regarding pathogenesis, immune responses, and outcomes SARS-CoV-2 virus, the causative agent of the coronavirus infectious disease-19 (COVID-19), is taking the globe by storm, approaching 500,000 confirmed cases and over 21,000 deaths as of March 25, 2020. While under control in some affected Asian countries (Taiwan, Singapore, Vietnam), the virus demonstrated an exponential phase of infectivity in several large countries (China in late January and February and many European countries and the USA in March), with cases exploding by 30–50,000/day in the third and fourth weeks of March, 2020. SARS-CoV-2 has proven to be particularly deadly to older adults and those with certain underlying medical conditions, many of whom are of advanced age. Here, we briefly review the virus, its structure and evolution, epidemiology and pathogenesis, immunogenicity and immune, and clinical response in older adults, using available knowledge on SARS-CoV-2 and its highly pathogenic relatives MERS-CoV and SARS-CoV-1. We conclude by discussing clinical and basic science approaches to protect older adults against this disease.

positive: A phased lift of control: a practical strategy to achieve herd immunity against Covid-19 at the country level Most countries are affected by the Covid-19 pandemic and experience rapidly increasing numbers of cases and deaths. Many have implemented nationwide stringent control to avoid overburdening the health care system. This paralyzes economic and social activities until the availability of a vaccine, which may take years. We propose an alternative exit strategy to develop herd immunity in a predictable and controllable way: a phased lift of control. This means that successive parts of the country (e.g. provinces) stop stringent control, and Covid-19-related IC admissions are distributed over the country as the whole. Importantly, vulnerable individuals need to be shielded until herd immunity has developed in their area. We explore the characteristics and duration of this strategy using a novel individual-based model for geographically stratified transmission of Covid-19 in a country. The model predicts that individuals will have to experience stringent control for about 14 months on average, but this duration may be significantly shortened by future developments (more IC beds, better drugs). Clearly, the strategy will have a profound impact on individuals and society, and should therefore be considered carefully by various other disciplines (e.g. health systems, ethics, economics) before actual implementation.

positive: Chapter 3 SARS coronavirus infections of the lower respiratory tract and their prevention Abstract The Severe Acute Respiratory Syndrome (SARS) coronavirus was first identified in 2003 when it caused an epidemic of fatal human pneumonia cases that rapidly spread to multiple countries from an epicenter in Hong Kong. The outbreak was eventually controlled by quarantine measures but not before it had caused many fatalities. The original zoonotic source of the SARS virus that caused the outbreak is still unknown but is suspected to be bats. Attempts were made to develop a prophylactic vaccine but the SARS epidemic was over before any vaccines could be tested for human efficacy. As will be discussed in this chapter, coronavirus vaccines present many challenges including low and rapidly waning immunity and the fact that coronavirus vaccines, particularly when formulated with Th2-biased alum adjuvants, can exacerbate coronavirus infection-associated eosinophilic lung immunopathology. Fortunately, this problem can be avoided by formulation of coronavirus vaccines with Th1-type adjuvants that enhance T cell IFN-γ responses, such as, delta inulin or TLR agonists. Hence, appropriate adjuvant selection is vitally important for the development of safe and effective coronavirus vaccines. This chapter will describe the current state of development of SARS vaccines, the issue of coronavirus-associated eosinophilic lung immunopathology and how adjuvants can be used to reduce the risk of this complication.

positive: Immune response to SARS‐CoV‐2 and mechanisms of immunopathological changes in COVID‐19 As a zoonotic disease that has already spread globally to several million human beings and possibly to domestic and wild animals, eradication of coronavirus disease 2019 (COVID‐19) appears practically impossible. There is a pressing need to improve our understanding of the immunology of this disease to contain the pandemic by developing vaccines and medicines for the prevention and treatment of patients. In this review, we aim to improve our understanding on the immune response and immunopathological changes in patients linked to detoriating clinical conditions such as, cytokine storm, acute respiratory distress syndrome, autopsy findings and changes in acute phase reactants and serum biochemistry in COVID‐19. Similar to many other viral infections, asymptomatic disease is present in a significant but currently unknown fraction of the affected individuals.In the majority of the patients, a one‐week, self‐limiting viral respiratory disease typically occurs, which ends with the development of neutralizing anti‐viral T cell and antibody immunity. The IgM, IgA and IgG type virus‐specific antibodies levels are important measurements to predict population immunity against this disease and whether cross‐reactivity with other coronaviruses is taking place.High viral‐load during the first infection and repeated exposure to virus especially in healthcare workers can be an important factor for severity of disease. It should be noted that many aspects of severe patients are unique to COVID‐19 and are rarely observed in other respiratory viral infections, such as severe lymphopenia and eosinopenia, extensive pneumonia and lung tissue damage, a cytokine storm leading to acute respiratory distress syndrome and multiorgan failure. Lymphopenia causes a defect in antiviral and immune regulatory immunity. At the same time, a cytokine storm starts with extensive activation of cytokine‐secreting cells with innate and adaptive immune mechanisms both of with contribute to a poor prognosis. Elevated levels of acute phase reactants and lymphopenia are early predictors of high disease severity. Prevention of development to severe disease, cytokine storm, acute respiratory distress syndrome and novel approachs to prevent their development will be main routes for future research areas. As we learn to live amidst the virus, understanding the immunology of the disease can assist in containing the pandemic and in developing vaccines and medicines to prevent and treat individual patients.

positive: Severe acute respiratory syndrome vaccine development: experiences of vaccination against avian infectious bronchitis coronavirus Vaccines against infectious bronchitis of chickens (Gallus gallus domesticus) have arguably been the most successful, and certainly the most widely used, of vaccines for diseases caused by coronaviruses, the others being against bovine, canine, feline and porcine coronaviruses. Infectious bronchitis virus (IBV), together with the genetically related coronaviruses of turkey (Meleagris gallopavo) and ring-necked pheasant (Phasianus colchicus), is a group 3 coronavirus, Severe acute respiratory syndrome (SARS) coronavirus being tentatively in group 4, the other known mammalian coronaviruses being in groups 1 and 2. IBV replicates not only in respiratory tissues (including the nose, trachea, lungs and airsacs, causing respiratory disease), but also in the kidney (associated with minor or major nephritis), oviduct, and in many parts of the alimentary tract—the oesophagus, proventriculus, duodenum, jejunum, bursa of Fabricius, caecal tonsils, rectum and cloaca, usually without clinical effects. The virus can persist, being re-excreted at the onset of egg laying (4 to 5 months of age), believed to be a consequence of the stress of coming into lay. Genetic lines of chickens differ in the extent to which IBV causes mortality in chicks, and in respect of clearance of the virus after the acute phase. Live attenuated (by passage in chicken embryonated eggs) IBV strains were introduced as vaccines in the 1950s, followed a couple of decades later by inactivated vaccines for boosting protection in egg-laying birds. Live vaccines are usually applied to meat-type chickens at 1 day of age. In experimental situations this can result in sterile immunity when challenged by virulent homologous virus. Although 100% of chickens may be protected (against clinical signs and loss of ciliary activity in trachea), sometimes 10% of vaccinated chicks may not respond with a protective immune response. Protection is short lived, the start of the decline being apparent 9 weeks after vaccination with vaccines based on highly attenuated strains. IBV exists as scores of serotypes (defined by the neutralization test), cross-protection often being poor. Consequently, chickens may be re-vaccinated, with the same or another serotype, two or three weeks later. Single applications of inactivated virus has generally led to protection of <50% of chickens. Two applications have led to 90 to 100% protection in some reports, but remaining below 50% in others. In practice in the field, inactivated vaccines are used in laying birds that have previously been primed with two or three live attenuated virus vaccinations. This increases protection of the laying birds against egg production losses and induces a sustained level of serum antibody, which is passed to progeny. The large spike glycoprotein (S) comprises a carboxy-terminal S2 subunit (approximately 625 amino acid residues), which anchors S in the virus envelope, and an amino-terminal S1 subunit (approximately 520 residues), believed to largely form the distal bulbous part of S. The S1 subunit (purified from IBV virus, expressed using baculovirus or expressed in birds from a fowlpoxvirus vector) induced virus neutralizing antibody. Although protective immune responses were induced, multiple inoculations were required and the percentage of protected chickens was too low (<50%) for commercial application. Remarkably, expression of S1 in birds using a non-pathogenic fowl adenovirus vector induced protection in 90% and 100% of chickens in two experiments. Differences of as little as 5% between the S1 sequences can result in poor cross-protection. Differences in S1 of 2 to 3% (10 to 15 amino acids) can change serotype, suggesting that a small number of epitopes are immunodominant with respect to neutralizing antibody. Initial studies of the role of the IBV nucleocapsid protein (N) in immunity suggested that immunization with bacterially expressed N, while not inducing protection directly, improved the induction of protection by a subsequent inoculation with inactivated IBV. In another study, two intramuscular immunizations of a plasmid expressing N induced protective immunity. The basis of immunity to IBV is not well understood. Serum antibody levels do not correlate with protection, although local antibody is believed to play a role. Adoptive transfer of IBV-infection-induced αβ T cells bearing CD8 antigen protected chicks from challenge infection. In conclusion, live attenuated IBV vaccines induce good, although short-lived, protection against homologous challenge, although a minority of individuals may respond poorly. Inactivated IBV vaccines are insufficiently efficacious when applied only once and in the absence of priming by live vaccine. Two applications of inactivated IBV are much more efficacious, although this is not a commercially viable proposition in the poultry industry. However, the cost and logistics of multiple application of a SARS inactivated vaccine would be more acceptable for the protection of human populations, especially if limited to targeted groups (e.g. health care workers and high-risk contacts). Application of a SARS vaccine is perhaps best limited to a minimal number of targeted individuals who can be monitored, as some vaccinated persons might, if infected by SARS coronavirus, become asymptomatic excretors of virus, thereby posing a risk to non-vaccinated people. Looking further into the future, the high efficacy of the fowl adenovirus vector expressing the IBV S1 subunit provides optimism for a live SARS vaccine, if that were deemed to be necessary, with the possibility of including the N protein gene.

positive: Longitudinal high-throughput TCR repertoire profiling reveals the dynamics of T cell memory formation after mild COVID-19 infection COVID-19 is a global pandemic caused by the SARS-CoV-2 coronavirus. T cell response is a critical part of both individual and herd immunity to SARS-CoV-2 and the efficacy of developed vaccines. However neither the dynamics and cross-reactivity of the SARS-CoV-2-specific T cell response nor the diversity of resulting immune memory are well understood. In this study we use longitudinal high-throughput T cell receptor sequencing to track changes in the T cell repertoire following two mild cases of COVID-19 infection. In both donors we identified SARS-CoV-2-responding CD4+ and CD8+ T cell clones. We describe characteristic motifs in TCR sequences of COVID-19-reactive clones, suggesting the existence of immunodominant epitopes. We show that in both donors the majority of infection-reactive clonotypes acquire memory phenotypes. Certain CD4+ clones were detected in the memory fraction at the pre-infection timepoint, suggesting participation of pre-existing cross-reactive memory T cells in the immune response to SARS-CoV-2.

positive: Can an effective SARS-CoV-2 vaccine be developed for the older population? The emergence of SARS-CoV-2 and its inordinately rapid spread is posing severe challenges to the wellbeing of millions of people worldwide, health care systems and the global economy. While many younger people experience no or mild symptoms on infection, older adults are highly susceptible to life-threatening respiratory and systemic conditions which demand a full understanding and leveraging of knowledge of the differences between immunity in young and old people. Consequently, we welcome papers addressing any issues relevant to immunity and ageing in the context of SARS-CoV-2, and will endeavour to fast-track peer-review. We aim to provide a platform exclusively for discussions of individual and age differences in susceptibility and immune responses to COVID caused by SARS-CoV-2 infection and how to prevent or reduce severity of disease in older adults.

positive: SARS-CoV-2 will continue to circulate in the human population: an opinion from the point of view of the virus-host relationship At the population level, the virus-host relationship is not set up to end with the complete elimination of either or both. Pathogen-resistant individuals will always remain in the host population. In turn, the virus can never completely eliminate the host population, because evolutionarily such an event is a dead end for the virus as an obligate intracellular parasite. A certain existential balance exists in the virus-host relationship. Against this backdrop, viral epidemics and pandemics only become manifest and egregious to human beings when tens and hundreds of thousands of people die and the question emerges what caused the high mortality peaks on the death chart. The answer seems clear; the emerging strain of the virus is new to the host population, and new mutations of the virus and natural selection will lead to a survival of only genetically resistant individuals in a host population. The dangers inherent to a novel virus are due to new features generally inthe molecular structure of proteins, which enable the virus to infect the cells of the host organism more intensively, dramatically challenging host immunity, and thus be transmitted more readily in the host population. In this article, we will concentrate on the facts currently available about severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which has caused COVID-19 (coronavirus disease 2019) pandemic and try to predict its development and consequences based on the virus-host relationship. In fact, only two scenarios will occur simultaneously in the very near future: people who are genetically resistant to the virus will get sick, recover, and develop immunity, while people who are sensitive to the virus will need drugs and vaccines, which will have to be researched and developed if they are to recover. If the pandemic does not stop, in a few decades it is anticipated that SARS-CoV-2 will become as safe as the four non-severe acute respiratory syndrome human coronaviruses (HCoV-NL63, HCoV-HKU1, HCoV-OC43, and HCoV-229E) currently circulating but causing low mortality in the human population.

positive: Airway Memory CD4(+) T Cells Mediate Protective Immunity against Emerging Respiratory Coronaviruses Two zoonotic coronaviruses (CoV), SARS-CoV and MERS-CoV have crossed species to cause severe human respiratory disease. Here, we showed that induction of airway memory CD4(+) T cells specific for a conserved epitope shared by SARS-CoV and MERS-CoV is a potential strategy for developing pan-coronavirus vaccines. Airway memory CD4(+) T cells differed phenotypically and functionally from lung-derived cells and were crucial for protection against both CoVs in mice. Protection was interferon-γ-dependent and required early induction of robust innate and virus-specific CD8(+) T cell responses. The conserved epitope was also recognized in SARS-CoV and MERS-CoV-infected human leukocyte antigen DR2 and DR3 transgenic mice, indicating potential relevance in human populations. Additionally, this epitope was cross-protective between human and bat CoVs, the progenitors for many human CoVs. Vaccine strategies that induce airway memory CD4(+) T cells targeting conserved epitopes may have broad applicability in the context of new CoV and other respiratory virus outbreaks.

positive: Cannabinoid Receptor Type 2: A Possible Target in SARS-CoV-2 (CoV-19) Infection? In late December 2019, a novel coronavirus (SARS-CoV-2 or CoV-19) appeared in Wuhan, China, causing a global pandemic. SARS-CoV-2 causes mild to severe respiratory tract inflammation, often developing into lung fibrosis with thrombosis in pulmonary small vessels and causing even death. COronaVIrus Disease (COVID-19) patients manifest exacerbated inflammatory and immune responses, cytokine storm, prevalence of pro-inflammatory M1 macrophages and increased levels of resident and circulating immune cells. Men show higher susceptibility to SARS-CoV-2 infection than women, likely due to estrogens production. The protective role of estrogens, as well as an immune-suppressive activity that limits the excessive inflammation, can be mediated by cannabinoid receptor type 2 (CB2). The role of this receptor in modulating inflammation and immune response is well documented in fact in several settings. The stimulation of CB2 receptors is known to limit the release of pro-inflammatory cytokines, shift the macrophage phenotype towards the anti-inflammatory M2 type and enhance the immune-modulating properties of mesenchymal stromal cells. For these reasons, we hypothesize that CB2 receptor can be a therapeutic target in COVID-19 pandemic emergency.

positive: Reverse genetic systems: Rational design of coronavirus live attenuated vaccines with immune sequelae Since the end of 2019, the global COVID-19 outbreak has once again made coronaviruses a hot topic. Vaccines are hoped to be an effective way to stop the spread of the virus. However, there are no clinically approved vaccines available for coronavirus infections. Reverse genetics technology can realize the operation of RNA virus genomes at the DNA level and provide new ideas and strategies for the development of new vaccines. In this review, we systematically describe the role of reverse genetics technology in studying the effects of coronavirus proteins on viral virulence and innate immunity, cell and tissue tropism and antiviral drug screening. An efficient reverse genetics platform is useful for obtaining the ideal attenuated strain to prepare an attenuated live vaccine.

positive: Clinical, molecular, and epidemiological characterization of the SARS-CoV-2 virus and the Coronavirus Disease 2019 (COVID-19), a comprehensive literature review Coronaviruses are an extensive family of viruses that can cause disease in both animals and humans. The current classification of coronaviruses recognizes 39 species in 27 subgenera that belong to the family Coronaviridae. From those, at least 7 coronaviruses are known to cause respiratory infections in humans. Four of these viruses can cause common cold-like symptoms. Those that infect animals can evolve and become infectious to humans. Three recent examples of these viral jumps include SARS CoV, MERS-CoV and SARS CoV-2 virus. They are responsible for causing severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS) and the most recently discovered coronavirus disease during 2019 (COVID-19). COVID-19, a respiratory disease caused by the SARS-CoV-2 virus, was declared a pandemic by the World Health Organization (WHO) on 11 March 2020. The rapid spread of the disease has taken the scientific and medical community by surprise. Latest figures from 20 May 2020 show more than 5 million people had been infected with the virus, causing more than 330,000 deaths in over 210 countries worldwide. The large amount of information received daily relating to COVID-19 is so abundant and dynamic that medical staff, health authorities, academics and the media are not able to keep up with this new pandemic. In order to offer a clear insight of the extensive literature available, we have conducted a comprehensive literature review of the SARS CoV-2 Virus and the Coronavirus Diseases 2019 (COVID-19).

positive: Modeling Exit Strategies from COVID-19 Lockdown with a Focus on Antibody Tests This paper presents two epidemiological models that have been developed in order to study the disease dynamics of the COVID-19 pandemic and exit strategies from the lockdown which has been imposed on many countries world-wide. A strategy is needed such that both the health system is not overloaded letting people die in an uncontrolled way and also such that the majority of people can get back their social contacts as soon as possible. We investigate the potential effects of a combination of measures such as continuation of hygienic constraints after leaving lockdown, isolation of infectious persons, repeated and adaptive short-term contact reductions and also large-scale use of antibody tests in order to know who can be assumed to be immune and participate at public life without constraints. We apply two commonly used modeling approaches: extended SEIR models formulated both as System Dynamics and Agent-Based Simulation, in order to get insight into the disease dynamics of a complete country like Germany and also into more detailed behavior of smaller regions. We confirm the findings of other models that without intervention the consequences of the pandemic can be catastrophic and we extend such findings with effective strategies to overcome the challenge. Based on the modeling assumptions it can be expected that repeated short-term contact reductions will be necessary in the next years to avoid overload of the health system and that on the other side herd immunity can be achieved and antibody tests are an effective way to mitigate the contact reductions for many.

positive: Coronaviruses and Neuroantigens: myelin proteins, myelin genes Multiple sclerosis (MS) is an autoimmune disease in which autoreactive T cells specific to central nervous system (CNS) myelin antigens are activated. Although disease etiology remains unknown, coronaviruses are suspected to be involved in MS pathology. Molecular mimicry, the recognition of two antigens by a single immune cell, could be the mechanism explaining the link between a viral infection and MS through activation of myelin-reactive T cells by a virus infection in a genetically predisposed individual. Evidence supporting this hypothesis in humans has been accumulated in our laboratory. Human coronavirus (HCoV) — myelin cross-reactive T-cell lines (TCL) were predominantly found in MS patients compared to patients with other neurological or inflammatory diseases, or healthy controls. Moreover, virus-myelin T cell cross-reactivity was confirmed at the clonal level. Molecular mimicry between infectious pathogens such as the ubiquitous human respiratory coronaviruses could, in genetically susceptible individuals, play a role leading to the development of MS. Together with other possible mechanisms such as bystander effects, epitope spreading or even superantigenic activities, this pathogen-associated immune induction could play a role in maintaining and broadening the autoimmune response associated with MS pathology.

positive: Immunogenic profile of SARS-CoV-2 spike in individuals recovered from COVID-19 The rapid global spread of SARS-CoV-2 and resultant mortality and social disruption have highlighted the need to better understand coronavirus immunity to expedite vaccine development efforts. Multiple candidate vaccines, designed to elicit protective neutralising antibodies targeting the viral spike glycoprotein, are rapidly advancing to clinical trial. However, the immunogenic properties of the spike protein in humans are unresolved. To address this, we undertook an in-depth characterisation of humoral and cellular immunity against SARS-CoV-2 spike in humans following mild to moderate SARS-CoV-2 infection. We find serological antibody responses against spike are routinely elicited by infection and correlate with plasma neutralising activity and capacity to block ACE2/RBD interaction. Expanded populations of spike-specific memory B cells and circulating T follicular helper cells (cTFH) were detected within convalescent donors, while responses to the receptor binding domain (RBD) constitute a minor fraction. Using regression analysis, we find high plasma neutralisation activity was associated with increased spike-specific antibody, but notably also with the relative distribution of spike-specific cTFH subsets. Thus both qualitative and quantitative features of B and T cell immunity to spike constitute informative biomarkers of the protective potential of novel SARS-CoV-2 vaccines.

positive: The dynamics of humoral immune responses following SARS-CoV-2 infection and the potential for reinfection SARS-CoV-2 is a novel coronavirus that is the causative agent of coronavirus infectious disease 2019 (COVID-19). As of 17 April 2020, it has infected 2â114â269 people, resulting in 145â144 deaths. The timing, magnitude and longevity of humoral immunity is not yet understood for SARS-CoV-2. Nevertheless, understanding this is urgently required to inform the likely future dynamics of the pandemic, to guide strategies to allow relaxation of social distancing measures and to understand how to deploy limiting vaccine doses when they become available to achieve maximum impact. SARS-CoV-2 is the seventh human coronavirus to be described. Four human coronaviruses circulate seasonally and cause common colds. Two other coronaviruses, SARS and MERS, have crossed from animal sources into humans but have not become endemic. Here we review what is known about the human humoral immune response to epidemic SARS CoV and MERS CoV and to the seasonal, endemic coronaviruses. Then we summarize recent, mostly non-peer reviewed, studies into SARS-CoV-2 serology and reinfection in humans and non-human primates and summarize current pressing research needs.

positive: Balancing Expediency and Scientific Rigor in Severe Acute Respiratory Syndrome Coronavirus 2 Vaccine Development

positive: Immune responses and pathogenesis in persistently PCR-positive patients with SARS-CoV-2 infection Coronavirus disease (COVID-19) caused by SARS-CoV-2 emerged in China in December 2019 and then rapidly spread worldwide. Why COVID-19 patients with the same clinical condition have different outcomes remains unclear. This study aimed to examine the differences in the phenotype and functions of major populations of immune cells between COVID-19 patients with same severity but different outcomes. Four common type adult inpatients with laboratory confirmed COVID-19 from Beijing YouAn Hospital, Capital Medical University were included in this study. The patients were divided into two groups based on whether or not COVID-19 PCR-negative conversion occurred within three weeks. Peripheral blood samples were collected to compare the differences in the phenotype and functions of major populations of immune cells between the two groups of patients. The result shows that the proportions of CD3+ CD8+ CD38+ HLA-DR+ CD27- effector T killer cells generally declined, whereas that of CD3+ CD4+ CD8+ double-positive T cells (DPTs) increased in the persistently PCR-positive patients. In summary, considering the imbalance between effector T killer cells/ CD3+CD4+CD8+ DPTs was a possible key factor for PCR-negative conversion in COVID-19 patients. This article is protected by copyright. All rights reserved.

positive: Immunity after COVID-19: protection or sensitization ? Motivated by historical and present clinical observations, we discuss the possible unfavorable evolution of the immunity (similar to documented antibody-dependent enhancement scenarios) after a first infection with COVID-19. More precisely we ask the question of how the epidemic outcomes are affected if the initial infection does not provide immunity but rather sensitization to future challenges. We first provide background comparison with the 2003 SARS epidemic. Then we use a compartmental epidemic model structured by immunity level (taken here as age classes) that we fit on available data; this allows to derive quantitative insights into the future number of severe cases and deaths.

positive: SARS-CoV-2 Reverse Genetics Reveals a Variable Infection Gradient in the Respiratory Tract The mode of acquisition and causes for the variable clinical spectrum of coronavirus disease 2019 (COVID-19) remain unknown. We utilized a reverse genetics system to generate a GFP reporter virus to explore severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pathogenesis and a luciferase reporter virus to demonstrate sera collected from SARS and COVID-19 patients exhibited limited cross-CoV neutralization. High-sensitivity RNA in situ mapping revealed the highest angiotensin-converting enzyme 2 (ACE2) expression in the nose with decreasing expression throughout the lower respiratory tract, paralleled by a striking gradient of SARS-CoV-2 infection in proximal (high) versus distal (low) pulmonary epithelial cultures. COVID-19 autopsied lung studies identified focal disease and, congruent with culture data, SARS-CoV-2-infected ciliated and type 2 pneumocyte cells in airway and alveolar regions, respectively. These findings highlight the nasal susceptibility to SARS-CoV-2 with likely subsequent aspiration-mediated virus seeding to the lung in SARS-CoV-2 pathogenesis. These reagents provide a foundation for investigations into virus-host interactions in protective immunity, host susceptibility, and virus pathogenesis.

positive: Routine childhood immunization may protect against COVID-19

positive: Identification of viral antigens that induce antibody responses on exposure to coronaviruses. Various techniques were used to look for protective, non-cross-reactive antibodies in the sera of cats exposed to virulent feline infectious peritonitis virus (FIPV). Antibodies reactive with feline enteric coronavirus (FECV) from FIPV-exposed cats were adsorbed by several passages over an FECV-Sepharose column. In an ELISA against FECV and FIPV, the activity against both viruses was removed at the same rate; thus, no FIPV-specific antibodies could be identified. By gel electrophoresis-derived ELISA, the responses of cats surviving FIPV exposure were compared with those of cats succumbing to FIPV exposure to determine whether survival could be correlated with an antibody response against a particular virus protein. Results indicated that both groups responded in the same way to the matrix envelope protein and nucleocapsid proteins. Even though the response to peplomer in each group was weak, the survivor group responded better to this protein. Furthermore, the response of this group to the peplomer protein had the highest correlation with virus neutralization titer.

positive: Enhancing immune responses against SARS-CoV nucleocapsid DNA vaccine by co-inoculating interleukin-2 expressing vector in mice The immunogenicity of SARS-CoV nucleocapsid DNA vaccine and the immunoregulatory activity of interleukin-2 (IL-2) were investigated. DNA vaccine plasmids, pcDNA-N and pcDNA-IL2, were constructed and inoculated into BALB/c mice with or without pcDNA-IL2 by intramuscular injection. Cellular and humoral immune responses were assessed by indirect ELISA, lymphocyte proliferation assays, ELISPOT and FACS. The nucleocapsid DNA vaccine had good immunogenicity and can induce specific humoral and cellular immunity in BALB/c mice, while IL-2 plays an immunoadjuvant role and enhances specific immune responses. This study provides a frame of reference for the design of DNA vaccines against SARS-CoV.

positive: Broad sarbecovirus neutralizing antibodies define a key site of vulnerability on the SARS-CoV-2 spike protein Broadly protective vaccines against known and pre-emergent coronaviruses are urgently needed. Critical to their development is a deeper understanding of cross-neutralizing antibody responses induced by natural human coronavirus (HCoV) infections. Here, we mined the memory B cell repertoire of a convalescent SARS donor and identified 200 SARS-CoV-2 binding antibodies that target multiple conserved sites on the spike (S) protein. A large proportion of the antibodies display high levels of somatic hypermutation and cross-react with circulating HCoVs, suggesting recall of pre-existing memory B cells (MBCs) elicited by prior HCoV infections. Several antibodies potently cross-neutralize SARS-CoV, SARS-CoV-2, and the bat SARS-like virus WIV1 by blocking receptor attachment and inducing S1 shedding. These antibodies represent promising candidates for therapeutic intervention and reveal a new target for the rational design of pan-sarbecovirus vaccines.

positive: Longitudinally Profiling Neutralizing Antibody Response to SARS Coronavirus with Pseudotypes The severe acute respiratory syndrome–associated coronavirus (SARS-CoV) spike protein (S) is a major target for neutralizing antibodies. Retroviral SARS-CoV S pseudotypes have been constructed and used to develop an in vitro microneutralization assay that is both sensitive and specific for SARS-CoV neutralizing antibodies. Neutralization titers measured by this assay are highly correlated to those measured by an assay using replication-competent SARS-CoV. No cross-neutralization occurred with human sera known to contain antibodies to coronavirus strains OC43 and 229E. The pseudotype assay was used to profile neutralizing antibody responses against SARS-CoV S in sequential serum samples taken from 41 confirmed SARS patients during the 2003 outbreak in Hong Kong and shows long-lasting immunity in most recovered patients. The pseudotype assay does not require handling live SARS virus; it is a useful tool to determine neutralizing titers during natural infection and the preclinical evaluation of candidate vaccines.

positive: Vaccines to prevent severe acute respiratory syndrome coronavirus-induced disease An important effort has been performed after the emergence of severe acute respiratory syndrome (SARS) epidemic in 2003 to diagnose and prevent virus spreading. Several types of vaccines have been developed including inactivated viruses, subunit vaccines, virus-like particles (VLPs), DNA vaccines, heterologous expression systems, and vaccines derived from SARS-CoV genome by reverse genetics. This review describes several aspects essential to develop SARS-CoV vaccines, such as the correlates of protection, virus serotypes, vaccination side effects, and bio-safeguards that can be engineered into recombinant vaccine approaches based on the SARS-CoV genome. The production of effective and safe vaccines to prevent SARS has led to the development of promising vaccine candidates, in contrast to the design of vaccines for other coronaviruses, that in general has been less successful. After preclinical trials in animal models, efficacy and safety evaluation of the most promising vaccine candidates described has to be performed in humans.

positive: A 219-mer CHO-expressing receptor-binding domain of SARS-CoV S protein induces potent immune responses and protective immunity. Development of vaccines is essential for the prevention of future recurrences of severe acute respiratory syndrome (SARS), caused by the SARS coronavirus (SARS-CoV). The spike (S) protein, especially receptor-binding domain (RBD) of SARS-CoV, plays important roles in the prevention of SARS infection, and is thus an important component in SARS vaccine development. In this study, we expressed a 219-mer (residues 318-536) RBD protein in Chinese hamster ovary (CHO)-K1 cells (RBD219-CHO), and tested its immune responses and protective immunity in a mouse model. The results showed that this recombinant protein was correctly folded, being able to maintain intact conformation and authentic antigenicity. It could induce strong humoral and cellular immune responses and high titers of neutralizing antibodies in the vaccinated mice. RBD219-CHO protein elicited potent protective immunity that protected all vaccinated mice from SARS-CoV challenge. These results suggest that the recombinant RBD219-CHO protein has great potential for the development of an effective and safe SARS subunit vaccine.

positive: The perplexing question of trained immunity versus adaptive memory in COVID-19 The wide spectrum of symptoms observed in COVID-19 appears to defy explanation. Apart from geographic limitation to people with prior exposure to other coronaviruses and air pollutants, inflammatory comordidities and older ages are also among the main factors of susceptibility to severe illness. The unusual epidemiological data pointed out in children and African territories have revealed new insights in host-pathogen interplay with more focus on epigenetic regulation of cognitive compartments belonging to innate immunity. Should trained immunity be proven to be involved in timely immune responsiveness against SARS-CoV-2 and that adaptive memory could be detrimental, both treatment regimens and vaccine design will tremendously change accordingly with more focus on upper respiratory tissue innate immunity to subdue this threat underway. This article is protected by copyright. All rights reserved.

positive: Coronavirus COV-19/SARS-CoV-2 affects women less than men: clinical response to viral infection. CoV-19/SARS-CoV-2 is a highly pathogenic virus that causes coronavirus-19 disease (COVID-19) an acute respiratory distress syndrome which provokes serious problems for global health. Studies suggest that there are many differences between men and women in the immune response to CoV-19 infection and inflammatory diseases. Women, compared to men, are less susceptible to viral infections based on a different innate immunity, steroid hormones and factors related to sex chromosomes. The presence of two X chromosomes in women emphasize the immune system even if one is inactive. The immune regulatory genes encoded by X chromosome in female gender causes lower viral load levels, and less inflammation than in man, while CD4+ T cells are higher with better immune response. In addition, women generally produce higher levels of antibodies which remain in the circulation longer. The levels of activation of the immune cells are higher in women than in men, and it is correlated with the trigger of TLR7 and the production of IFN. TLR7 is higher in women than in men and its biallelic expression leads to higher immune responses and increases the resistance to viral infections. TLR7 is expressed in innate immune cells which recognizes single strand RNA virus by promoting the production of antibodies against the virus and the generation of pro-inflammatory cytokines including IL-6 and IL-1 family members. Moreover, in women the production of inflammatory IL-6 after viral infection is lower than in males and is often correlated with a better longevity. In addition, on the X chromosome there are loci that code for the genes involved in the regulation of immune cells such as FOXP3, and transcription factor for Treg involved in virus pathogenesis. The X chromosome influences the immune system by acting on many other proteins, including TLR8, CD40L and CXCR3 which can be over-expressed in women, and influence the response to viral infections and vaccinations. However, the biallelic expression of the X-linked genes can promote harmful autoimmune and inflammatory responses. Cardiovascular diseases are more frequent in males and subjects without cardiovascular dysfunctions infected by CoV-19 have a better prognosis. ACE2 is a receptor for CoV-19 and protects lung damage. CoV-19 infection and the virus's Spike protein inhibit the expression of ACE2, abolishing its protective function. Inhibitors of the angiotensin converting enzyme (ACEI) are used to stem the devastating effects of CoV-19, to increase the number of CD3 and CD8 T cells and to reduce the viral load and IL-6 levels that control CoV-19 replication via NF-B, but these effects are still under study. It is hoped that certain drugs, such as CoV-19 receptor blockers, anti-inflammatories (against rheumatic diseases), monoclonal antibodies, anti-IL-1 and anti-IL-6, the remdesevir drug (analogue adenosine, effective against ebola), hydroxychloroquine (for the treatment of malaria) and vaccines, will open up new strategies and new therapeutic ways to combat this terrible virus.

positive: Epigenetic Landscape during Coronavirus Infection Coronaviruses (CoV) comprise a large group of emerging human and animal pathogens, including the highly pathogenic severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV) strains. The molecular mechanisms regulating emerging coronavirus pathogenesis are complex and include virus–host interactions associated with entry, replication, egress and innate immune control. Epigenetics research investigates the genetic and non-genetic factors that regulate phenotypic variation, usually caused by external and environmental factors that alter host expression patterns and performance without any change in the underlying genotype. Epigenetic modifications, such as histone modifications, DNA methylation, chromatin remodeling, and non-coding RNAs, function as important regulators that remodel host chromatin, altering host expression patterns and networks in a highly flexible manner. For most of the past two and a half decades, research has focused on the molecular mechanisms by which RNA viruses antagonize the signaling and sensing components that regulate induction of the host innate immune and antiviral defense programs upon infection. More recently, a growing body of evidence supports the hypothesis that viruses, even lytic RNA viruses that replicate in the cytoplasm, have developed intricate, highly evolved, and well-coordinated processes that are designed to regulate the host epigenome, and control host innate immune antiviral defense processes, thereby promoting robust virus replication and pathogenesis. In this article, we discuss the strategies that are used to evaluate the mechanisms by which viruses regulate the host epigenome, especially focusing on highly pathogenic respiratory RNA virus infections as a model. By combining measures of epigenome reorganization with RNA and proteomic datasets, we articulate a spatial-temporal data integration approach to identify regulatory genomic clusters and regions that play a crucial role in the host’s innate immune response, thereby defining a new viral antagonism mechanism following emerging coronavirus infection.

positive: SARS-CoV2 coronavirus: So far polite with children. Debatable immunological and non-immunological evidence Abstract The reasons for the relative resistance of children to certain infections such as that caused by coronavirus SARS- CoV2 are not yet fully clear. Deciphering these differences can provide important information about the pathogenesis of the disease. Regarding the SARS-CoV2 virus, children are at the same risk of infection as the general population of all ages, with the most serious cases being found in infants. However, it has been reported that the disease is much less frequent than in adults and that most cases are benign or moderate (even with high viral loads), provided there are no other risk factors or underlying diseases. It is not clear why they have lower morbidity and virtually no mortality. A series of findings, relationships and behavioral patterns between the infectious agent and the child host may account for the lower incidence and a greatly attenuated clinical presentation of the disease in children.

positive: Immunization with SARS Coronavirus Vaccines Leads to Pulmonary Immunopathology on Challenge with the SARS Virus BACKGROUND: Severe acute respiratory syndrome (SARS) emerged in China in 2002 and spread to other countries before brought under control. Because of a concern for reemergence or a deliberate release of the SARS coronavirus, vaccine development was initiated. Evaluations of an inactivated whole virus vaccine in ferrets and nonhuman primates and a virus-like-particle vaccine in mice induced protection against infection but challenged animals exhibited an immunopathologic-type lung disease. DESIGN: Four candidate vaccines for humans with or without alum adjuvant were evaluated in a mouse model of SARS, a VLP vaccine, the vaccine given to ferrets and NHP, another whole virus vaccine and an rDNA-produced S protein. Balb/c or C57BL/6 mice were vaccinated IM on day 0 and 28 and sacrificed for serum antibody measurements or challenged with live virus on day 56. On day 58, challenged mice were sacrificed and lungs obtained for virus and histopathology. RESULTS: All vaccines induced serum neutralizing antibody with increasing dosages and/or alum significantly increasing responses. Significant reductions of SARS-CoV two days after challenge was seen for all vaccines and prior live SARS-CoV. All mice exhibited histopathologic changes in lungs two days after challenge including all animals vaccinated (Balb/C and C57BL/6) or given live virus, influenza vaccine, or PBS suggesting infection occurred in all. Histopathology seen in animals given one of the SARS-CoV vaccines was uniformly a Th2-type immunopathology with prominent eosinophil infiltration, confirmed with special eosinophil stains. The pathologic changes seen in all control groups lacked the eosinophil prominence. CONCLUSIONS: These SARS-CoV vaccines all induced antibody and protection against infection with SARS-CoV. However, challenge of mice given any of the vaccines led to occurrence of Th2-type immunopathology suggesting hypersensitivity to SARS-CoV components was induced. Caution in proceeding to application of a SARS-CoV vaccine in humans is indicated.

positive: The possible beneficial adjuvant effect of influenza vaccine to minimize the severity of COVID-19

positive: Virus-Induced T Cell-Mediated Heterologous Immunity and Vaccine Development Heterologous immunity (H.I.) is a consequence of an encounter with a specific antigen, which can alter the subsequent immune response to a different antigen. This can happen at the innate immune system level—often called trained immunity or innate immune memory—and/or at the adaptive immune system level involving T memory cells and antibodies. Viruses may also induce T cell-mediated H.I., which can confer protection or drive immunopathology against other virus subtypes, related or unrelated viruses, other pathogens, auto- or allo-antigens. It is important to understand the underlying mechanisms for the development of antiviral “universal” vaccines and broader T cell responses rather than just subtype-specific antibody responses as in the case of influenza. Furthermore, knowledge about determinants of vaccine-mediated H.I. may inform public health policies and provide suggestions for repurposing existing vaccines. Here, we introduce H.I. and provide an overview of evidence on virus- and antiviral vaccine-induced T cell-mediated cross-reactive responses. We also discuss the factors influencing final clinical outcome of virus-mediated H.I. as well as non-specific beneficial effects of live attenuated antiviral vaccines such as measles and vaccinia. Available epidemiological and mechanistic data have implications both for the development of new vaccines and for personalized vaccinology, which are presented. Finally, we formulate future research priorities and opportunities.

positive: Intranasal immunization with plasmid DNA encoding spike protein of SARS-coronavirus/polyethylenimine nanoparticles elicits antigen-specific humoral and cellular immune responses BACKGROUND: Immunization with the spike protein (S) of severe acute respiratory syndrome (SARS)-coronavirus (CoV) in mice is known to produce neutralizing antibodies and to prevent the infection caused by SARS-CoV. Polyethylenimine 25K (PEI) is a cationic polymer which effectively delivers the plasmid DNA. RESULTS: In the present study, the immune responses of BALB/c mice immunized via intranasal (i.n.) route with SARS DNA vaccine (pci-S) in a PEI/pci-S complex form have been examined. The size of the PEI/pci-S nanoparticles appeared to be around 194.7 ± 99.3 nm, and the expression of the S mRNA and protein was confirmed in vitro. The mice immunized with i.n. PEI/pci-S nanoparticles produced significantly (P < 0.05) higher S-specific IgG1 in the sera and mucosal secretory IgA in the lung wash than those in mice treated with pci-S alone. Compared to those in mice challenged with pci-S alone, the number of B220(+ )cells found in PEI/pci-S vaccinated mice was elevated. Co-stimulatory molecules (CD80 and CD86) and class II major histocompatibility complex molecules (I-A(d)) were increased on CD11c(+ )dendritic cells in cervical lymph node from the mice after PEI/pci-S vaccination. The percentage of IFN-γ-, TNF-α- and IL-2-producing cells were higher in PEI/pci-S vaccinated mice than in control mice. CONCLUSION: These results showed that intranasal immunization with PEI/pci-S nanoparticles induce antigen specific humoral and cellular immune responses.

positive: CD8+ T Cells Responding to the Middle East Respiratory Syndrome Coronavirus Nucleocapsid Protein Delivered by Vaccinia Virus MVA in Mice Middle East respiratory syndrome coronavirus (MERS-CoV), a novel infectious agent causing severe respiratory disease and death in humans, was first described in 2012. Antibodies directed against the MERS-CoV spike (S) protein are thought to play a major role in controlling MERS-CoV infection and in mediating vaccine-induced protective immunity. In contrast, relatively little is known about the role of T cell responses and the antigenic targets of MERS-CoV that are recognized by CD8+ T cells. In this study, the highly conserved MERS-CoV nucleocapsid (N) protein served as a target immunogen to elicit MERS-CoV-specific cellular immune responses. Modified Vaccinia virus Ankara (MVA), a safety-tested strain of vaccinia virus for preclinical and clinical vaccine research, was used for generating MVA-MERS-N expressing recombinant N protein. Overlapping peptides spanning the whole MERS-CoV N polypeptide were used to identify major histocompatibility complex class I/II-restricted T cell responses in BALB/c mice immunized with MVA-MERS-N. We have identified a H2-d restricted decamer peptide epitope in the MERS-N protein with CD8+ T cell antigenicity. The identification of this epitope, and the availability of the MVA-MERS-N candidate vaccine, will help to evaluate MERS-N-specific immune responses and the potential immune correlates of vaccine-mediated protection in the appropriate murine models of MERS-CoV infection.

positive: BCG-induced trained immunity: can it offer protection against COVID-19? Bacillus Calmette–Guérin (BCG) vaccination has been reported to decrease susceptibility to respiratory tract infections, an effect proposed to be mediated by the general long-term boosting of innate immune mechanisms, also termed trained immunity. Here, we discuss the non-specific beneficial effects of BCG against viral infections and whether this vaccine may afford protection to COVID-19.

positive: Pathogenic priming likely contributes to serious and critical illness and mortality in COVID-19 via autoimmunity Abstract Homology between human and viral proteins is an established factor in viral- or vaccine-induced autoimmunity. Failure of SARS and MERS vaccines in animal trials involved pathogenesis consistent with an immunological priming that could involve autoimmunity in lung tissues due to previous exposure to the SARS and MERS spike protein. Exposure pathogenesis to SARS-CoV-2 in COVID-19 likely will lead to similar outcomes. Immunogenic peptides in viruses or bacteria that match human proteins are good candidates for pathogenic priming peptides (similar to the more diffuse idea of “immune enhancement”). Here I provide an assessment of potential for human pathogenesis via autoimmunity via exposure, via infection or injection. SAR-CoV-2 spike proteins, and all other SARS-CoV-2 proteins, immunogenic epitopes in each SARS-CoV-2 protein were compared to human proteins in search of high local homologous matching. Only one immunogenic epitope in a SARS-CoV-2 had no homology to human proteins. If all of the parts of the epitopes that are homologous to human proteins are excluded from consideration due to risk of pathogenic priming, the remaining immunogenic parts of the epitopes may be still immunogenic and remain as potentially viable candidates for vaccine development. Mapping of the genes encoding human protein matches to pathways point to targets that could explain the observed presentation of symptoms in COVID-19 disease. It also strongly points to a large number of opportunities for expected disturbances in the immune system itself, targeting elements of MHC Class I and Class II antigen presentation, PD-1 signaling, cross-presentation of soluble exogenous antigens and the ER-Phagosome pathway. Translational consequences of these findings are explored.

positive: Amino terminus of the SARS coronavirus protein 3a elicits strong, potentially protective humoral responses in infected patients. The 3a protein of severe acute respiratory syndrome (SARS)-associated coronavirus is expressed and transported to the plasma membrane in tissue cells of infected patients. Its short N-terminal ectodomain was found to elicit strong humoral responses in half of the patients who had recovered from SARS. The ectodomain-specific antibodies from the convalescent-phase plasma readily recognized and induced destruction of 3a-expressing cells in the presence of the human complement system, demonstrating their potential ability to provide immune protection by recognizing and eliminating SARS coronavirus-infected cells that express the target protein. In addition, when coupled to a carrier protein, the ectodomain peptide elicited 3a-specific antibodies in mice and rabbit at high titres. These results showed that the N terminus of the 3a protein is highly immunogenic and elicits potentially protective humoral responses in infected patients. Therefore, the short extracellular domain may be a valuable immunogen in the development of a vaccine for infectious SARS.

positive: An Effective CTL Peptide Vaccine for Ebola Zaire Based on Survivors’ CD8+ Targeting of a Particular Nucleocapsid Protein Epitope with Potential Implications for COVID-19 Vaccine Design The 2013-2016 West Africa EBOV epidemic was the biggest EBOV outbreak to date. An analysis of virus-specific CD8+ T-cell immunity in 30 survivors showed that 26 of those individuals had a CD8+ response to at least one EBOV protein. The dominant response (25/26 subjects) was specific to the EBOV nucleocapsid protein (NP). It has been suggested that epitopes on the EBOV NP could form an important part of an effective T-cell vaccine for Ebola Zaire. We show that a 9-amino-acid peptide NP44-52 (YQVNNLEEI) located in a conserved region of EBOV NP provides protection against morbidity and mortality after mouse adapted EBOV challenge. A single vaccination in a C57BL/6 mouse using an adjuvanted microsphere peptide vaccine formulation containing NP44-52 is enough to confer immunity in mice. Our work suggests that a peptide vaccine based on CD8+ T-cell immunity in EBOV survivors is conceptually sound and feasible. Nucleocapsid proteins within SARS-CoV-2 contain multiple class I epitopes with predicted HLA restrictions consistent with broad population coverage. A similar approach to a CTL vaccine design may be possible for that virus.

positive: Recent Progress in Studies of Arterivirus- and Coronavirus-Host Interactions Animal coronaviruses, such as infectious bronchitis virus (IBV), and arteriviruses, such as porcine reproductive and respiratory syndrome virus (PRRSV), are able to manifest highly contagious infections in their specific native hosts, thereby arising in critical economic damage to animal industries. This review discusses recent progress in studies of virus-host interactions during animal and human coronavirus and arterivirus infections, with emphasis on IBV-host cell interactions. These interactions may be directly involved in viral replication or lead to the alteration of certain signaling pathways, such as cell stress response and innate immunity, to facilitate viral replication and pathogenesis.

positive: Intranasal immunization with inactivated SARS-CoV (SARS-associated coronavirus) induced local and serum antibodies in mice SARS-CoV (severe acute respiratory syndrome-associated coronavirus) strain GZ50 was partially purified and inactivated with 1:2000 formaldehyde. In cell culture the inactivated virus blocked the replication of live virus by decreasing the TCID(5.0) of the live virus 10(3.6) to 10(4.6) times. Inactivated GZ50 was used to immunize mice intranasally either alone, or after precipitation with polyethylene glycol (PEG), or with CpG, or CTB as an adjuvant. The titer of serum neutralizing antibodies was up to 1:640. In mice immunized with adjuvants or PEG precipitated GZ50, specific IgA was detected in tracheal-lung wash fluid by immunofluorescence. Though serum antibodies were detected, no anti-SARS-IgA could be detected in mice immunized only with inactivated GZ50. The roles of adjuvants in intranasal immunization with inactivated. SARS-CoV is discussed.

positive: Characterization of the SARS-CoV-2 Spike in an Early Prefusion Conformation Pandemic coronavirus disease 2019 (COVID-19) is caused by the emerging severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), for which there are no efficacious vaccines or therapeutics that are urgently needed. We expressed three versions of spike (S) proteins—receptor binding domain (RBD), S1 subunit and S ectodomain—in insect cells. RBD appears monomer in solutions, whereas S1 and S associate into homotrimer with substantial glycosylation. The three proteins confer excellent antigenicity with six convalescent COVID-19 patient sera. Cryo-electron microscopy (cryo-EM) analyses indicate that the SARS-CoV-2 S trimer dominate in a unique conformation distinguished from the classic prefusion conformation of coronaviruses by the upper S1 region at lower position ~15 Å proximal to viral membrane. Such conformation is proposed as an early prefusion state for the SARS-CoV-2 spike that may broaden the knowledge of coronavirus and facilitate vaccine development.

positive: Will children reveal their secret? The coronavirus dilemma Epidemiological evidences show that SARS-CoV-2 infection in children is less frequent and severe than adults. Age-related ACE2 receptor expression, lymphocyte count and trained immunity might be the keystone to reveal children's secret.

positive: Evidence of a significant secretory-IgA-dominant SARS-CoV-2 immune response in human milk following recovery from COVID-19 SARS-CoV-2, commonly termed COVID-19 for the illness it causes, has infected >3.2 million people, including >220,000 deaths. Human milk IgG originates mainly from blood, therefore a SARS-CoV-2-reactive antibody (Ab) response in milk would be expected (1). However, IgG comprises only ~2% of milk Ab, with most milk Abs originating from mucosa-associated lymphatic tissue (1). Therefore, the extent of the milk immune response to SARS-CoV-2 is unknown (2). This response is critical for infants and young children, who tend not to suffer greatly from COVID-19 pathology but are likely responsible for significant virus transmission (3-5). Perhaps even more significant is the fact that milk Abs could be purified and used as a COVID-19 therapeutic, given they would likely be of the secretory (s) class and highly resistant to proteolytic degradation in the respiratory tissue (2, 6). In this preliminary report, 15 milk samples obtained from donors previously-infected with SARS-CoV-2 as well as 10 negative control samples obtained prior to December 2019 were tested for reactivity to the Receptor Binding Domain (RBD) of the SARS-CoV-2 Spike protein by ELISAs measuring IgA, IgG, IgM, and secretory Ab. Eighty percent of samples obtained post-COVID-19 exhibited IgA reactivity, and all these samples were also positive for secretory Ab reactivity, suggesting the IgA is predominantly sIgA. COVID-19 group mean OD values of undiluted milk were significantly greater for IgA (p<0.0001), secretory-type Abs (p<0.0001), and IgG (p=0.017), but not for IgM, compared to pre-pandemic group mean values. Overall, these data indicate that there is strong sIgA-dominant SARS-CoV-2 immune response in human milk after infection in the majority of individuals, and that a comprehensive study of this response is highly warranted.

positive: Vaccines for COVID-19: the current state of play There is a strong consensus globally that a COVID-19 vaccine is likely the most effective approach to sustainably controlling the COVID-19 pandemic. An unprecedented research effort and global coordination has resulted in a rapid development of vaccine candidates and initiation of trials. Here, we review vaccine types, and progress with 10 vaccine candidates against SARS-CoV-2 – the virus that causes COVID-19 - currently undergoing early phase human trials. We also consider the many challenges of developing and deploying a new vaccine on a global scale, and recommend caution with respect to our expectations of the timeline that may be ahead.

positive: Cross-protection studies between feline infectious peritonitis and porcine transmissible gastroenteritis viruses Cross-protection studies between the feline infectious peritonitis (FIP) and the porcine transmissible gastroenteritis (TGE) viruses were conducted in cats, pigs and pregnant gilts. Cats vaccinated with TGE virus developed neutralizing antibodies against TGE virus and low titer antibody against FIP virus detected by an indirect fluorescent antibody technique but were not protected against a virulent FIP virus challenge. Baby pigs and pregnant gilts vaccinated with FIP virus did not develop detectable antibodies to TGE virus. Nevertheless, it appeared that vaccination of swine with FIP virus conferred some immunity against TGE virus infection. Seventeen-day-old pigs vaccinated with two doses of FIP virus had a 67% survival rate following a virulent TGE virus challenge, and 75% of the 3-day-old pigs suckling either FIP or TGE-virus-vaccinated gilts survived virulent TGE virus infection in contrast to 0% survival of baby pigs suckling unvaccinated gilts.

positive: Can the protection be among us? Previous viral contacts and prevalent HLA alleles could be avoiding an even more disseminated COVID-19 pandemic. Background: COVID-19 is bringing scenes of sci-fi movies into real life, and it seems to be far from over. Infected individuals exhibit variable severity, with no relation between the number of cases and mortality, suggesting the involvement of the populational genetic constitution and previous cross-reactive immune contacts in the individuals' disease outcome. Methods: A clustering approach was conducted to investigate the involvement of human MHC alleles with individuals' outcomes. HLA frequencies from affected countries were used to fuel the Hierarchical Clusterization Analysis. The formed groups were compared regarding their death rates. To prospect the T cell targets in SARS-CoV-2, and by consequence, the epitopes that are conferring cross-protection in the current pandemic, we modeled 3D structures of HLA-A*02:01 presenting immunogenic epitopes from SAR-CoV-1, recovered from Immune Epitope Database. These pMHC structures were also compared with models containing the corresponding SARS-CoV-2 epitope, with alphacoronavirus sequences, and with a panel of immunogenic pMHC structures contained in CrossTope. Findings: The combined use of HLA-B*07, HLA-B*44, HLA-DRB1*03, and HLADRB1*04 allowed the clustering of affected countries presenting similar death rates, based only on their allele frequencies. SARS-CoV HLA-A*02:01 epitopes were structurally investigated. It reveals molecular conservation between SARS-CoV-1 and SARS-CoV-2 peptides, enabling the use of formerly SARS-CoV-1 experimental epitopes to inspect actual targets that are conferring cross-protection. Alpha-CoVs and, impressively, viruses involved in human infections share fingerprints of immunogenicity with SARS-CoV peptides. Interpretation: Wide-scale HLA genotyping in COVID-19 patients shall improve prognosis prediction. Structural identification of previous triggers paves the way for herd immunity examination and wide spectrum vaccine development. Funding: This work was supported by the National Council for Scientific and Technological Development (CNPq) and National Council for the Improvement of Higher Education (CAPES) for their support

positive: A possible role of immunopathogenesis in COVID-19 progression Background: The efficacy of the humoral and cellular immunity determines the outcome of viral infections. An appropriate immune response mediates protection, whereas an overwhelming immune response has been associated with immune-mediated pathogenesis in viral infections. The current study explored the general and SARS-CoV-2 specific cellular and humoral immune status in patients with different COVID-19 severities. Methods: In this prospective study, we included 53 patients with moderate, severe, and critical COVID-19 manifestations comparing their quantitative, phenotypic, and functional characteristics of circulating immune cells, SARS-CoV-2 antigen specific T-cells, and humoral immunity. Results: Significantly diminished frequencies of CD8+T-cells, CD4+ and CD8+T-cell subsets with activated differentiated memory/effector phenotype and migratory capacity were found in circulation in patients with severe and/or critical COVID-19 as compared to patients with moderate disease. Importantly, the improvement of the clinical courses from severe to moderate was accompanied by an improvement in the T-cell subset alterations. Furthermore, we surprisingly observed a detectable SARS-CoV-2-reactive T-cell response in all three groups after stimulation with SARS-CoV-2 S-protein overlapping peptide pool already at the first visit. Of note, patients with a critical COVID-19 demonstrated a stronger response of SARS-CoV-2-reactive T-cells producing Th1 associated inflammatory cytokines. Furthermore, clear correlation between antibody titers and SARS-CoV-2-reactive CD4+ frequencies underscore the role of specific immunity in disease progression. Conclusion: Our data demonstrate that depletion of activated memory phenotype circulating T-cells and a strong SARS-CoV-2-specific cellular and humoral immunity are associated with COVID-19 disease severity. This counter-intuitive finding may have important implications for diagnostic, therapeutic and prophylactic COVID-19 management.

positive: SARS-CoV-2 epitopes are recognized by a public and diverse repertoire of human T-cell receptors Understanding the determinants of adaptive immune response to SARS-CoV-2 is critical for fighting the ongoing COVID-19 pandemic. Here we assayed both antibody and T-cell reactivity to SARS-CoV-2 antigens in COVID-19 convalescent patients and healthy donors sampled before and during the pandemic. Our results show that while anti-SARS-CoV-2 antibodies can distinguish convalescent patients from healthy donors, the magnitude of T-cell response was more pronounced in healthy donors sampled during COVID-19 pandemic than in donors sampled before the outbreak. This hints at the possibility that some individuals have encountered the virus but were protected by T-cell cross-reactivity observed. A public and diverse T-cell response was observed for two A*02-restricted SARS-CoV-2 epitopes, revealing a set of T-cell receptor motifs displaying germline-encoded features. Bulk CD4+ and CD8+ T-cell response to SARS-CoV-2 glycoprotein S is characterized by multiple groups of homologous T-cell receptor sequences some of which are shared across multiple donors, indicating the existence of immunodominant epitopes. Overall, our findings indicate that T cells form an efficient response to SARS-CoV-2 and alongside the antibodies can serve as a useful biomarker for surveying SARS-CoV-2 exposure and immunity. We hope that data, including the set of specific T-cell receptors identified in this study can serve as a basis for future developments of SARS-CoV-2 vaccinations and monitoring.

positive: The dynamics of humoral immune responses following SARS-CoV-2 infection and the potential for reinfection. SARS-CoV-2 is a novel coronavirus that is the causative agent of coronavirus infectious disease 2019 (COVID-19). As of 17 April 2020, it has infected 2 114 269 people, resulting in 145 144 deaths. The timing, magnitude and longevity of humoral immunity is not yet understood for SARS-CoV-2. Nevertheless, understanding this is urgently required to inform the likely future dynamics of the pandemic, to guide strategies to allow relaxation of social distancing measures and to understand how to deploy limiting vaccine doses when they become available to achieve maximum impact. SARS-CoV-2 is the seventh human coronavirus to be described. Four human coronaviruses circulate seasonally and cause common colds. Two other coronaviruses, SARS and MERS, have crossed from animal sources into humans but have not become endemic. Here we review what is known about the human humoral immune response to epidemic SARS CoV and MERS CoV and to the seasonal, endemic coronaviruses. Then we summarize recent, mostly non-peer reviewed, studies into SARS-CoV-2 serology and reinfection in humans and non-human primates and summarize current pressing research needs.

positive: Targets of T cell responses to SARS-CoV-2 coronavirus in humans with COVID-19 disease and unexposed individuals Summary Understanding adaptive immunity to SARS-CoV-2 is important for vaccine development, interpreting coronavirus disease 2019 (COVID-19) pathogenesis, and calibration of pandemic control measures. Using HLA class I and II predicted peptide ‘megapools’, circulating SARS-CoV-2−specific CD8+ and CD4+ T cells were identified in ∼70% and 100% of COVID-19 convalescent patients, respectively. CD4+ T cell responses to spike, the main target of most vaccine efforts, were robust and correlated with the magnitude of the anti-SARS-CoV-2 IgG and IgA titers. The M, spike and N proteins each accounted for 11-27% of the total CD4+ response, with additional responses commonly targeting nsp3, nsp4, ORF3a and ORF8, among others. For CD8+ T cells, spike and M were recognized, with at least eight SARS-CoV-2 ORFs targeted. Importantly, we detected SARS-CoV-2−reactive CD4+ T cells in ∼40-60% of unexposed individuals, suggesting cross-reactive T cell recognition between circulating ‘common cold’ coronaviruses and SARS-CoV-2.

positive: Long-Term Persistence of Robust Antibody and Cytotoxic T Cell Responses in Recovered Patients Infected with SARS Coronavirus Most of the individuals infected with SARS coronavirus (SARS-CoV) spontaneously recovered without clinical intervention. However, the immunological correlates associated with patients' recovery are currently unknown. In this report, we have sequentially monitored 30 recovered patients over a two-year period to characterize temporal changes in SARS-CoV-specific antibody responses as well as cytotoxic T cell (CTL) responses. We have found persistence of robust antibody and CTL responses in all of the study subjects throughout the study period, with a moderate decline one year after the onset of symptoms. We have also identified two potential major CTL epitopes in N proteins based on ELISPOT analysis of pooled peptides. However, despite the potent immune responses and clinical recovery, peripheral lymphocyte counts in the recovered patients have not yet been restored to normal levels. In summary, our study has, for the first time, characterized the temporal and dynamic changes of humoral and CTL responses in the natural history of SARS-recovered individuals, and strongly supports the notion that high and sustainable levels of immune responses correlate strongly with the disease outcome. Our findings have direct implications for future design and development of effective therapeutic agents and vaccines against SARS-CoV infection.

positive: Virus-specific memory CD8 T cells provide substantial protection from lethal severe acute respiratory syndrome coronavirus infection. UNLABELLED Severe acute respiratory syndrome coronavirus (SARS-CoV) caused an acute human respiratory illness with high morbidity and mortality in 2002-2003. Several studies have demonstrated the role of neutralizing antibodies induced by the spike (S) glycoprotein in protecting susceptible hosts from lethal infection. However, the anti-SARS-CoV antibody response is short-lived in patients who have recovered from SARS, making it critical to develop additional vaccine strategies. SARS-CoV-specific memory CD8 T cells persisted for up to 6 years after SARS-CoV infection, a time at which memory B cells and antivirus antibodies were undetectable in individuals who had recovered from SARS. In this study, we assessed the ability of virus-specific memory CD8 T cells to mediate protection against infection in the absence of SARS-CoV-specific memory CD4 T or B cells. We demonstrate that memory CD8 T cells specific for a single immunodominant epitope (S436 or S525) substantially protected 8- to 10-month-old mice from lethal SARS-CoV infection. Intravenous immunization with peptide-loaded dendritic cells (DCs) followed by intranasal boosting with recombinant vaccinia virus (rVV) encoding S436 or S525 resulted in accumulation of virus-specific memory CD8 T cells in bronchoalveolar lavage fluid (BAL), lungs, and spleen. Upon challenge with a lethal dose of SARS-CoV, virus-specific memory CD8 T cells efficiently produced multiple effector cytokines (gamma interferon [IFN-γ], tumor necrosis factor alpha [TNF-α], and interleukin 2 [IL-2]) and cytolytic molecules (granzyme B) and reduced lung viral loads. Overall, our results show that SARS-CoV-specific memory CD8 T cells protect susceptible hosts from lethal SARS-CoV infection, but they also suggest that SARS-CoV-specific CD4 T cell and antibody responses are necessary for complete protection. IMPORTANCE Virus-specific CD8 T cells are required for pathogen clearance following primary SARS-CoV infection. However, the role of SARS-CoV-specific memory CD8 T cells in mediating protection after SARS-CoV challenge has not been previously investigated. In this study, using a prime-boost immunization approach, we showed that virus-specific CD8 T cells protect susceptible 8- to 10-month-old mice from lethal SARS-CoV challenge. Thus, future vaccines against emerging coronaviruses should emphasize the generation of a memory CD8 T cell response for optimal protection.

positive: A chimeric multi-epitope DNA vaccine elicited specific antibody response against severe acute respiratory syndrome-associated coronavirus which attenuated the virulence of SARS-CoV in vitro Abstract Epitope-based vaccines designed to induce antibody responses specific for severe acute respiratory syndrome-associated coronavirus (SARS-CoV) are being developed as a means for increasing vaccine potency. In this study, we identified four B cell epitopes from the spike (S) and membrane (M) protein through bioinformatics analysis and constructed a multi-epitope DNA vaccine. Intramuscular immunization of mice with this vaccine was sufficient to induce specific prime as well as a long-term memory humoral immune response to at least two candidate epitopes, S437–459 and M1–20. A DNA prime–protein boost strategy greatly enhanced the antibody generation and the immune sera not only reacted with the lysates of SARS-CoV-infected Vero cells but also neutralized the cytopathic effect of SARS by 75% at 1:160 dilution. The novel immunogenic S protein peptide revealed in this study provides new target for SARS vaccine design; and our work indicated multi-epitope DNA vaccine as an effective means for eliciting polyvalent humoral immune response against SARS-CoV.

positive: Could Intravenous Immunoglobulin Collected from Recovered Coronavirus Patients Protect against COVID-19 and Strengthen the Immune System of New Patients? The emergence of the novel coronavirus in Wuhan, China, which causes severe respiratory tract infections in humans (COVID-19), has become a global health concern. Most coronaviruses infect animals but can evolve into strains that cross the species barrier and infect humans. At the present, there is no single specific vaccine or efficient antiviral therapy against COVID-19. Recently, we showed that intravenous immunoglobulin (IVIg) treatment reduces inflammation of intestinal epithelial cells and eliminates overgrowth of the opportunistic human fungal pathogen Candida albicans in the murine gut. Immunotherapy with IVIg could be employed to neutralize COVID-19. However, the efficacy of IVIg would be better if the immune IgG antibodies were collected from patients who have recovered from COVID-19 in the same city, or the surrounding area, in order to increase the chance of neutralizing the virus. These immune IgG antibodies will be specific against COVID-19 by boosting the immune response in newly infected patients. Different procedures may be used to remove or inactivate any possible pathogens from the plasma of recovered coronavirus patient derived immune IgG, including solvent/detergent, 60 °C heat-treatment, and nanofiltration. Overall, immunotherapy with immune IgG antibodies combined with antiviral drugs may be an alternative treatment against COVID-19 until stronger options such as vaccines are available.

positive: Energetics based epitope screening in SARS CoV-2 (COVID 19) spike glycoprotein by Immuno-informatic analysis aiming to a suitable vaccine development The recent outbreak by SARS-CoV-2 has generated a chaos in global health and economy and claimed/infected a large number of lives. Closely resembling with SARS CoV, the present strain has manifested exceptionally higher degree of spreadability, virulence and stability possibly due to some unidentified mutations. The viral spike glycoprotein is very likely to interact with host Angiotensin-Converting Enzyme 2 (ACE2) and transmits its genetic materials and hijacks host machinery with extreme fidelity for self propagation. Few attempts have been made to develop a suitable vaccine or ACE2 blocker or virus-receptor inhibitor within this short period of time. Here, attempt was taken to develop some therapeutic and vaccination strategies with a comparison of spike glycoproteins among SARS-CoV, MERS-CoV and the SARS-CoV-2. We verified their structure quality (SWISS-MODEL, Phyre2, Pymol) topology (ProFunc), motifs (MEME Suite, GLAM2Scan), gene ontology based conserved domain (InterPro database) and screened several epitopes (SVMTrip) of SARS CoV-2 based on their energetics, IC50 and antigenicity with regard to their possible glycosylation and MHC/paratopic binding (Vaxigen v2.0, HawkDock, ZDOCK Server) effects. We screened here few pairs of spike protein epitopic regions and selected their energetic, IC50, MHC II reactivity and found some of those to be very good target for vaccination. A possible role of glycosylation on epitopic region showed profound effects on epitopic recognition. The present work might be helpful for the urgent development of a suitable vaccination regimen against SARS CoV-2.

positive: SARS and MERS: recent insights into emerging coronaviruses The emergence of Middle East respiratory syndrome coronavirus (MERS-CoV) in 2012 marked the second introduction of a highly pathogenic coronavirus into the human population in the twenty-first century. The continuing introductions of MERS-CoV from dromedary camels, the subsequent travel-related viral spread, the unprecedented nosocomial outbreaks and the high case-fatality rates highlight the need for prophylactic and therapeutic measures. Scientific advancements since the 2002–2003 severe acute respiratory syndrome coronavirus (SARS-CoV) pandemic allowed for rapid progress in our understanding of the epidemiology and pathogenesis of MERS-CoV and the development of therapeutics. In this Review, we detail our present understanding of the transmission and pathogenesis of SARS-CoV and MERS-CoV, and discuss the current state of development of measures to combat emerging coronaviruses. SUPPLEMENTARY INFORMATION: The online version of this article (doi:10.1038/nrmicro.2016.81) contains supplementary material, which is available to authorized users.

positive: In-depth phenotyping of human peripheral blood mononuclear cells in convalescent COVID-19 patients following a mild versus severe disease course Background: Covid-19, the disease caused by infection with SARS-CoV-2, has developed to a pandemic causing more than 239, 000 deaths worldwide as of 6th May according to the World Health Organization (WHO). It presents with a highly variable disease course ranging from a large proportion of asymptomatic cases to severe respiratory failure in 17-29% of cases even in the absence of apparent comorbidities 1, 2. This implies a diverse host immune response to SARS-CoV-2. The immunological characteristics underlying these divergent disease courses, however, still remain elusive. While insights into abrogations of innate immunity begin to emerge, adaptive immune responses towards SARS-CoV-2 are poorly investigated, although they serve as immune signatures of protection and vaccine responses. We therefore set out to characterize immune signatures of convalescent COVID-19 patients stratified according to their disease severity. Methods: We performed high-dimensional flow cytometric profiling of peripheral blood mononuclear cells of convalescent COVID-19 patients who we stratified according to their disease severity by a physician-assisted questionnaire based assessment of COVID-19 symptoms. Results: Surprisingly, we did not observe any difference in the relative proportions of any major immune cell type in convalescent patients presenting with different severity of COVID-19 disease except for a reduction in monocytes. The frequency of Tnaive T cells was significantly reduced in CD4+ and CD8+ T cells, whereas other T cell differentiations states (TCM, TEM, TEMRA) remained relatively unaffected by COVID-19 severity as assessed approximately two weeks after infection. Conclusions In our COVID-19 patient cohort, which is characterized by absence of comorbidities and therapeutic interventions other than symptomatic antipyretics, the immunophenotype is similar irrespective of a highly variable disease severity. Convalescence is therefore associated with a rather uniform immune signature. Abrogations, which were previously identified in the innate and adaptive immune compartment of COVID-19 patients should be scrutinized for direct associations with a preconditioned immune system shaped and made vulnerable for SARS-CoV-2 by preexisting comorbidities.

positive: A consideration of publication-derived immune-related associations in Coronavirus and related lung damaging diseases The severe acute respiratory syndrome virus SARS-CoV-2, a close relative of the SARS-CoV virus, is the cause of recent COVID-19 pandemic affecting, to date, over a 2 million individuals across the globe and demonstrating relatively high rates of infection and mortality. A third virus, the H5N1, responsible for avian influenza, has caused infection with some clinical similarities to those in COVID-19 infections. Cytokines, small proteins that modulate immune responses, have been directly implicated in some of the severe responses seen in COVID-19 patients, e.g. cytokine storms. Understanding the immune processes related to COVID-19, and other similar infections, could help identify diagnostic markers and therapeutic targets. Here we examine data of cytokine, immune cell types, and disease associations captured from biomedical literature associated with coronavirus, SARS, and H5N1 influenza, with the objective of identifying potentially useful relationships and areas for future research. Cytokine and cell-type associations captured from MeSH terms linked to thousands of PubMed abstracts, has identified differing patterns of associations between the three corpuses of abstracts (coronavirus, SARS, or H5N1 influenza). Clustering of cytokine-disease co-occurrences in the context of coronavirus has identified compelling clusters of co-morbidities and symptoms, some of which already known to be linked to COVID-19. Finally, network analysis identified sub-networks of cytokines and immune cell types associated with different manifestations, co-morbidities and symptoms of coronavirus, SARS, and H5N1. Systematic review of research in medicine is essential to facilitate evidence-based choices about health interventions. In a fast moving pandemic the approach taken here will identify trends and enable rapid comparison to the literature of related diseases.

positive: Potential T-cell and B-cell Epitopes of 2019-nCoV As of early March, 2019-nCoV has infected more than one hundred thousand people and claimed thousands of lives. 2019-nCoV is a novel form of coronavirus that causes COVID-19 and has high similarity with SARS-CoV. No approved vaccine yet exists for any form of coronavirus. Here we use computational tools from structural biology and machine learning to identify 2019-nCoV T-cell and B-cell epitopes based on viral protein antigen presentation and antibody binding properties. These epitopes can be used to develop more effective vaccines and identify neutralizing antibodies. We identified 405 viral peptides with good antigen presentation scores for both human MHC-I and MHC-II alleles, and two potential neutralizing B-cell epitopes near the 2019-nCoV spike protein receptor binding domain (440-460 and 494-506). Analyzing mutation profiles of 68 viral genomes from four continents, we identified 96 coding-change mutations. These mutations are more likely to occur in regions with good MHC-I presentation scores (p=0.02). No mutations are present near the spike protein receptor binding domain. Based on these findings, the spike protein is likely immunogenic and a potential vaccine candidate. We validated our computational pipeline with SARS-CoV experimental data. The novel coronavirus 2019-nCoV has affected more than 100 countries and continues to spread. There is an immediate need for effective vaccines that contain antigens which trigger responses from human T-cells and B-cells (known as epitopes). Here we identify potential T-cell epitopes through an analysis of human antigen presentation, as well as B-cell epitopes through an analysis of protein structure. We identify a list of top candidates, including an epitope located on 2019-nCoV spike protein that potentially triggers both T-cell and B-cell responses. Analyzing 68 samples, we observe that viral mutations are more likely to happen in regions with strong antigen presentation, a potential form of immune evasion. Our computational pipeline is validated with experimental data from SARS-CoV.

positive: SARS – CoV -2: reasons of epidemiology of severe ill disease cases and therapeutic approach using trivalent vaccine (tetanus, diphtheria and Bordetella pertussis) Abstract The novel coronavirus COVID-19 follows transmission route and clinical presentation of all community-acquired coronaviruses. Instead, the rate of transmission is significative higher, with a faster spread of the virus responsible of the worldwide outbreak and a significative higher mortality rate due to the development of a severe lung injury. Most noteworthy is the distribution of death rate among age groups. Children and younger people are almost protected from severe clinical presentation. Possible explanation of this phenomenon could be the ability of past vaccinations (especially tetanic, diphtheria toxoids and inactivated bacteria as pertussis) to stimulate immune system and to generate a scattered immunity against non-self antigens in transit, as coronaviruses and other community-circulating viruses and make immune system readier to develop specific immunity against COVID-19. The first support to this hypothesis is the distribution of mortality rate during historical pandemics (“Spanish flu” 1918, “Asian flu” 1956 and “the Hong Kong flu” 1968) among age groups before and after the introduction of vaccines. The immunological support to the hypothesis derives from recent studies about immunotherapy for malignancies, which propose the use of oncolytic vaccines combined with toxoids in order to exploit CD4+ memory T cell recall in supporting the ongoing anti-tumour response. According to this hypothesis vaccine formulations (tetanus, diphtheria, Bordetella pertussis) could be re-administrate after the first contact with Covid-19, better before the development of respiratory severe illness and of course before full-blown ARDS (Acute Respiratory Distress Syndrome). The CD4+ memory exploiting could help immune system to recall immunity of already know antigens against coronaviruses, avoiding or limiting “lung crash” until virus specific immunity develops and making it faster and prolonged. Finally, this administration could be helpful not only in already infected patients, but also before infection. In fact, people could have an immune system more ready when the contact with the COVID-19 will occur.

positive: Anti–Severe Acute Respiratory Syndrome Coronavirus Immune Responses: The Role Played by Vγ9Vδ2 T Cells Severe acute respiratory syndrome (SARS) is caused by a novel coronavirus (SARS-CoV) strain. Analyses of T cell repertoires in health care workers who survived SARS-CoV infection during the 2003 outbreak revealed that their effector memory Vγ9Vδ2 T cell populations were selectively expanded ∼3 months after the onset of disease. No such expansion of their αβ T cell pools was detected. The expansion of the Vγ9Vδ2 T cell population was associated with higher anti–SARS-CoV immunoglobulin G titers. In addition, in vitro experiments demonstrated that stimulated Vγ9Vδ2 T cells display an interferon-γ–dependent anti–SARS-CoV activity and are able to directly kill SARS-CoV–infected target cells. These findings are compatible with the possibility that Vγ9Vδ2 T cells play a protective role during SARS

positive: Molecular mechanisms of severe acute respiratory syndrome (SARS) Severe acute respiratory syndrome (SARS) is a new infectious disease caused by a novel coronavirus that leads to deleterious pulmonary pathological features. Due to its high morbidity and mortality and widespread occurrence, SARS has evolved as an important respiratory disease which may be encountered everywhere in the world. The virus was identified as the causative agent of SARS due to the efforts of a WHO-led laboratory network. The potential mutability of the SARS-CoV genome may lead to new SARS outbreaks and several regions of the viral genomes open reading frames have been identified which may contribute to the severe virulence of the virus. With regard to the pathogenesis of SARS, several mechanisms involving both direct effects on target cells and indirect effects via the immune system may exist. Vaccination would offer the most attractive approach to prevent new epidemics of SARS, but the development of vaccines is difficult due to missing data on the role of immune system-virus interactions and the potential mutability of the virus. Even in a situation of no new infections, SARS remains a major health hazard, as new epidemics may arise. Therefore, further experimental and clinical research is required to control the disease.

positive: Dissecting antibody-mediated protection against SARS-CoV-2

positive: Antibodies to coronaviruses are higher in older compared with younger adults and binding antibodies are more sensitive than neutralizing antibodies in identifying coronavirus-associated illnesses Human coronaviruses (HCoV) are common causes of respiratory illnesses (RI) despite preexisting humoral immunity. Sera were obtained near the onset of RI and 3 to 4 weeks later as part of a prospective study of 200 subjects evaluated for RI from 2009 to 2013. Antibodies against common HCoV strains were measured by enzyme-linked immunosorbent assay and neutralization assay comparing older adults with cardiopulmonary diseases (99 subjects) to younger, healthy adults (101 subjects). Virus shedding was detected in respiratory secretions by polymerase chain reaction. Of 43 HCoV-associated illnesses, 15 (35%) occurred in 14 older adults (aged ≥60 years) and 28 (65%) in 28 younger adults (aged 21-40 years). Binding and neutralizing antibodies were higher in older adults. Only 16 (35.7%) of RI with increases in binding antibodies also had increases in neutralizing antibodies to HCoV. Increases in binding antibodies with RI were more frequent than increased neutralizing antibodies and virus shedding, and more frequent in younger compared to older adults. Functional neutralizing antibodies were not stimulated as often as binding antibodies, explaining in part a susceptibility to reinfection with HCoV. Monitoring binding antibodies may be more sensitive for the serologic detection of HCoV infections.

positive: Potent cross-reactive neutralization of SARS coronavirus isolates by human monoclonal antibodies. The severe acute respiratory syndrome coronavirus (SARS-CoV) caused a worldwide epidemic in late 2002/early 2003 and a second outbreak in the winter of 2003/2004 by an independent animal-to-human transmission. The GD03 strain, which was isolated from an index patient of the second outbreak, was reported to resist neutralization by the human monoclonal antibodies (hmAbs) 80R and S3.1, which can potently neutralize isolates from the first outbreak. Here we report that two hmAbs, m396 and S230.15, potently neutralized GD03 and representative isolates from the first SARS outbreak (Urbani, Tor2) and from palm civets (SZ3, SZ16). These antibodies also protected mice challenged with the Urbani or recombinant viruses bearing the GD03 and SZ16 spike (S) glycoproteins. Both antibodies competed with the SARS-CoV receptor, ACE2, for binding to the receptor-binding domain (RBD), suggesting a mechanism of neutralization that involves interference with the SARS-CoV-ACE2 interaction. Two putative hot-spot residues in the RBD (Ile-489 and Tyr-491) were identified within the SARS-CoV spike that likely contribute to most of the m396-binding energy. Residues Ile-489 and Tyr-491 are highly conserved within the SARS-CoV spike, indicating a possible mechanism of the m396 cross-reactivity. Sequence analysis and mutagenesis data show that m396 might neutralize all zoonotic and epidemic SARS-CoV isolates with known sequences, except strains derived from bats. These antibodies exhibit cross-reactivity against isolates from the two SARS outbreaks and palm civets and could have potential applications for diagnosis, prophylaxis, and treatment of SARS-CoV infections.

positive: Vaccination Strategies to Promote Mucosal Antibody Responses There are great interest and demand for the development of vaccines to prevent and treat diverse microbial infections. Mucosal vaccines elicit immune protection by stimulating the production of antibodies at mucosal surfaces and systemic districts. Being positioned in close proximity to a large community of commensal microbes, the mucosal immune system deploys a heterogeneous population of cells and a complex regulatory network to maintain the balance between surveillance and tolerance. A successful mucosal vaccine relies on leveraging the functions of these immune cells and regulatory components. This article reviews the important cellular interactions and molecular pathways underlying the induction and regulation of mucosal antibody responses and discusses their implications on mucosal vaccination.

positive: Evaluation of the EUROIMMUN Anti-SARS-CoV-2 ELISA Assay for detection of IgA and IgG antibodies As the Coronavirus 2019 (COVID-19) pandemic evolves, the development of immunoassays to help determine exposure and potentially predict immunity has become a pressing priority. In this report we present the performance of the EUROIMMUN enzyme-linked immunosorbent assay (ELISA) for semi-quantitative detection of IgA and IgG antibodies in serum and plasma samples using recombinant S1 domain of the SARS-CoV-2 spike protein as antigen. Specimens from patients, with and without COVID-19 infection, were tested at the University of Chicago Clinical Microbiology and Immunology Laboratory. Of 57 samples from COVID-19 PCR-negative patients, including 28 samples positive for common human coronavirus strains, 53 tested negative and 4 tested positive for IgA (93.0% agreement) while 56 tested negative and 1 tested positive for IgG (98.2% agreement). For COVID-19 PCR-positive patients, 29 of 30 (96.7%) samples collected ≥3 days after positive PCR were positive for IgA, and 28 of 28 samples collected ≥4 days after positive PCR were positive for IgG. The EUROIMMUN Anti-SARS-CoV-2 ELISA Assay demonstrates excellent sensitivity for detection of IgA and IgG antibodies from samples collected ≥3 days and ≥4 days, respectively, after COVID-19 diagnosis by PCR. This assay did not demonstrate cross reaction in any of the 28 samples from patients with common human coronaviruses, including types HKU1, NL63, CV229E, and OC43.

positive: Coronavirus infections in the laboratory rat: degree of cross protection following immunization with a heterologous strain. One hundred and twenty-one specific pathogen-free male Wistar rats eight to ten weeks of age were used to evaluate the efficacy of Parker's rat coronavirus (PRC) in affording cross protection on subsequent challenge with virulent sialodacryoadenitis (SDA) virus. Sixty-two animals were inoculated intranasally on day 0 and 21 days later with approximately 10(2) median tissue culture infective doses (TCID50) of the tenth passage of PRC replicated in L-2 cells. Animals were selected at random postvaccination to evaluate the safety and efficacy of PRC by histopathology, immunohistochemistry and serology. At three and six months postvaccination (PV), vaccinated and seronegative control rats were inoculated intranasally with approximately 10(3) TCID50 doses of virulent SDA virus. Challenged rats were then killed at 6, 10 and 14 days postchallenge and necropsied. Evaluations were based on lesion indices in lacrimal and salivary glands and respiratory tract, the presence of viral antigen by immunohistochemistry, and antibody response. Lesions were observed in rats killed PV, but in general, they were significantly reduced compared with those present in seronegative animals post-exposure to virulent SDA virus (p < or = 0.05). However, they were still considered to be an unacceptable level for a routine vaccination procedure. Potvaccination antibody titers to rat coronavirus were evident in all animals tested at three or six months prior to challenge with SDA virus.(ABSTRACT TRUNCATED AT 250 WORDS)

positive: Effect of mucosal and systemic immunization with virus-like particles of severe acute respiratory syndrome coronavirus in mice Nasal administration has emerged as a promising and attractive route for vaccination, especially for the prophylaxis of respiratory diseases. Our previous studies have shown that severe acute respiratory syndrome coronavirus (SARS-CoV) virus-like particles (VLPs) can be assembled using a recombinant baculovirus (rBV) expression system and such VLPs induce specific humoral and cellular immune responses in mice after subcutaneous injection. Here, we investigated mucosal immune responses to SARS-CoV VLPs in a mouse model. Mice were immunized in parallel, intraperitoneally or intranasally, with VLPs alone or with VLPs plus cytosine–phosphate–guanosine (CpG). Immune responses, including the production of SARS-CoV-specific serum immunoglobulin G (IgG) and secretory immunoglobulin A (sIgA), were determined in mucosal secretions and tissues. Both immunizations induced SARS-CoV-specific IgG, although the levels of IgG in groups immunized via the intraperitoneal (i.p.) route were higher. sIgA was detected in saliva in groups immunized intranasally but not in groups immunized intraperitoneally. CpG had an adjuvant effect on IgA production in genital tract washes when administered intranasally but only affected IgA production in faeces samples when administered intraperitoneally. In addition, IgA was also detected in mucosal tissues from the lung and intestine, while CpG induced an increased level of IgA in the intestine. Most importantly, neutralization antibodies were detected in sera after i.p. and intranasal (i.n.) immunizations. Secretions in genital tract washes from the i.n. group also showed neutralization activity. Furthermore, VLPs that were administered intraperitoneally elicited cellular immune responses as demonstrated by enzyme-linked immunospot (ELISPOT) assay analyses. In summary, our study indicates that mucosal immunization with rBV SARS-CoV VLPs represent an effective means for eliciting protective systemic and mucosal immune responses against SARS-CoV, providing important information for vaccine design.

positive: Coronavirus immunogens Abstract Coronaviruses (CV) infect a variety of livestock, poultry and companion animals. They belong to at least five antigenic groups. CV cause localized infections of the respiratory and/or intestinal tracts, with the exception of feline infectious peritonitis virus (FIVP) and hemagglutinating encephalomyelitis (HEV) which cause systemic infections. The enteropathogenic CV infect the villous enterocytes resulting in villous atrophy leading to malabsorptive diarrhea. Several CV (bovine CV-BCV, porcine respiratory CV-PRCV, infectious bronchitis virus-IBV) cause respiratory disease. Current evidence indicates that protection against enteric and respiratory CV infections is mediated by passive or active immunity at the primary site of CV replication. Maternal vaccination approaches to induce passive immunity include the use of inactivated and modified live viral vaccines. Modified live viruses and a Ts mutant CV (FIPV) are also used as oral or intranasal vaccines to induce active mucosal immunity. The success of these vaccines in the field is often compromised by a number of potential problems. Coronaviruses are spherical, enveloped viruses, ranging from 80–160 nm in diameter and containing a positive-stranded RNA genome. They possess prominent surface spikes and some species display a fringe of smaller surface projections believed to be the hemagglutinin (HE). Coronaviruses possess 3 to 4 structural proteins: the spike (S) glycoprotein (150–200 kDa), the integral membrane glycoprotein (M; 20–30 kDa) and the nucleocapsid phosphoprotein (N; 43–50 kDa). A subset of CV (BCV, HEV, turkey CV) possess a third glycoprotein on the virion surface, the HE (60–65 kDa). These proteins can be quantitated using pooled monoclonal antibodies (mAb) to distinct epitopes of each protein in ELISA. Most research has focused on the S protein as a candidate antigen for CV vaccines since it induces virus neutralizing (VN) antibodies. However the HE protein stimulates the production of VN and HE inhibiting antibodies and the M protein induces antibodies that neutralize virus in the presence of complement. Attempts to correlate in vitro VN antibody activity with in vivo protection have shown that the passive transfer of VN mAb to the S or HE protein conferred passive protection against CV challenge in some studies, but not others. Additional research has implicated a possible role for other CV proteins in immunity. Studies of mAb to the M protein of transmissible gastroenteritis (TGEV) have provided evidence for a direct role of the M protein in the induction of αIFN by porcine blood leukocytes. The potential significance of this phenomenon to immunity to TGEV is unclear. Similarly, studies of IBV have suggested that determinants recognized by T cells reside on the N protein and these determinants may be shared among heterologous strains of IBV, resulting in the induction of cross-protection. Thus epitopes on the N protein may be important for induction of cell mediated immunity (CMI). CMI may play an important role in protection of cats against FIPV, since induction of circulating antibodies to the S protein of FIPV contributes to disease pathogenesis by the induction of immune complexes and antibody dependent enhancement of the infectivity of FIPV for macrophages. An increased understanding of antibody and CMI responses following natural CV infections in animals is needed to identify the antigens and epitopes that induce protective immune responses. The expression of CV structural protein genes in various vectors will provide the recombinant proteins needed for future immunogenicity studies in the host species. Furthermore, live rDNA vectors that replicate in the gut and express coronavirus genes may provide a new generation of coronavirus vaccines.

positive: Antigen Production in Plant to Tackle Infectious Diseases Flare Up: The Case of SARS Severe acute respiratory syndrome (SARS) is a dangerous infection with pandemic potential. It emerged in 2002 and its aetiological agent, the SARS Coronavirus (SARS-CoV), crossed the species barrier to infect humans, showing high morbidity and mortality rates. No vaccines are currently licensed for SARS-CoV and important efforts have been performed during the first outbreak to develop diagnostic tools. Here we demonstrate the transient expression in Nicotiana benthamiana of two important antigenic determinants of the SARS-CoV, the nucleocapsid protein (N) and the membrane protein (M) using a virus-derived vector or agro-infiltration, respectively. For the M protein, this is the first description of production in plants, while for plant-derived N protein we demonstrate that it is recognized by sera of patients from the SARS outbreak in Hong Kong in 2003. The availability of recombinant N and M proteins from plants opens the way to further evaluation of their potential utility for the development of diagnostic and protection/therapy tools to be quickly manufactured, at low cost and with minimal risk, to face potential new highly infectious SARS-CoV outbreaks.

positive: Breadth of concomitant immune responses underpinning viral clearance and patient recovery in a non-severe case of COVID-19 We report the kinetics of the immune response in relation to clinical and virological features of a patient with mild-to-moderate coronavirus disease-19 (COVID-19) requiring hospitalisation. Increased antibody-secreting cells, follicular T-helper cells, activated CD4+ and CD8+ T-cells and IgM/IgG SARS-CoV-2-binding antibodies were detected in blood, prior to symptomatic recovery. These immunological changes persisted for at least 7 days following full resolution of symptoms, indicating substantial anti-viral immunity in this non-severe COVID-19.

positive: Diverse CD8 T Cell Responses to Viral Infection Revealed by the Collaborative Cross Enhanced host protection against re-infection requires generation of memory T cells of sufficient quantity and functional quality. Unlike well-studied inbred mice, T cell responses of diverse size and quality are generated following infection of humans and outbred mice. Thus, additional models are needed that accurately reflect variation in immune outcomes in genetically diverse populations and to uncover underlying genetic causes. The Collaborative Cross (CC), a large recombinant inbred panel of mice, is an ideal model in this pursuit for the high degree of genetic variation present, because it allows for assessment of genetic factors underlying unique phenotypes. Here, we advance the utility of the CC as a tool to analyze the immune response to viral infection. We describe variability in resting immune cell composition and adaptive immune responses generated among CC strains following systemic virus infection and reveal quantitative trait loci responsible for generation of CD62L+ memory CD8 T cells.

positive: Possible causes for decreased susceptibility of children to coronavirus

positive: Projecting the transmission dynamics of SARS-CoV-2 through the postpandemic period It is urgent to understand the future of severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) transmission. We used estimates of seasonality, immunity, and cross-immunity for human coronavirus OC43 (HCoV-OC43) and HCoV-HKU1 using time-series data from the United States to inform a model of SARS-CoV-2 transmission. We projected that recurrent wintertime outbreaks of SARS-CoV-2 will probably occur after the initial, most severe pandemic wave. Absent other interventions, a key metric for the success of social distancing is whether critical care capacities are exceeded. To avoid this, prolonged or intermittent social distancing may be necessary into 2022. Additional interventions, including expanded critical care capacity and an effective therapeutic, would improve the success of intermittent distancing and hasten the acquisition of herd immunity. Longitudinal serological studies are urgently needed to determine the extent and duration of immunity to SARS-CoV-2. Even in the event of apparent elimination, SARS-CoV-2 surveillance should be maintained because a resurgence in contagion could be possible as late as 2024.

positive: Immunity after natural exposure to enteric canine coronavirus does not provide complete protection against infection with the new pantropic CB/05 strain Abstract Recently, an outbreak of fatal infection caused by a pantropic variant (strain CB/05) of canine coronavirus (CCoV) has been reported. In this study, evidence is provided that immunity induced by natural exposure to enteric CCoV is not fully protective against strain CB/05. Twenty-two, 10-week-old beagles with a recent natural infection by enteric CCoV were randomly distributed in two experimental groups of eight (groups A and B) and one control group of six (group C) dogs. Dogs in groups A and B were inoculated oronasally with different doses (4×105 or 4×103 TCID50) of the pantropic strain CB/05, whereas dogs in group C were used as negative controls. Clinical, post-mortem and virological investigations showed that, despite the high serum antibody titres induced by the prior natural infection with enteric CCoV, dogs were susceptible to experimental infection with strain CB/05. This was shown by the occurrence of faecal shedding, and dogs displaying moderate clinical signs, mainly vomiting and diarrhoea. Involvement of the lymphoid tissues was evident as demonstrated by the acute lymphopenia (below 70% of the initial counts), gross lesions in spleen and lymph nodes and detection of CB/05 RNA in thymus, spleen and lymph nodes of some infected dogs. The presence of viral RNA in lymphoid tissues was observed only in dogs euthanised in the early stages of infection and the clinical course of the infection was unrelated to the viral dose administered. The present study demonstrates that strain CB/05 is able to induce infection and disease in dogs seropositive to enteric CCoV, thus highlighting the need for extensive epidemiological investigation and for the possible development of novel antigenically relevant vaccines.

positive: Long period dynamics of viral load and antibodies for SARS-CoV-2 infection: an observational cohort study ABSTRACT OBJECTIVE To investigate the dynamics of viral RNA, IgM, and IgG and their relationships in patients with SARS-CoV-2 pneumonia over an 8-week period. DESIGN Retrospective, observational case series. SETTING Wenzhou Sixth Peoples Hospital PARTICIPANTS Thirty-three patients with laboratory confirmed SARS-CoV-2 pneumonia admitted to hospital. Data were collected from January 27 to April 10, 2020. MAIN OUTCOME MEASURES Throat swabs, sputum, stool, and blood samples were collected, and viral load was measured by reverse transcription PCR (RT-PCR). Specific IgM and IgG against spike protein (S), spike protein receptor binding domain (RBD), and nucleocapsid (N) were analyzed. RESULTS At the early stages of symptom onset, SARS-CoV-2 viral load is higher in throat swabs and sputum, but lower in stool. The median (IQR) time of undetectable viral RNA in throat swab, sputum, and stool was 18.5 (13.25-22) days, 22 (18.5-27.5) days, and 17 (11.5-32) days, respectively. In sputum, 17 patients (51.5%) had undetectable viral RNA within 22 days (short persistence), and 16 (48.5%) had persistent viral RNA more than 22 days (long persistence). Three patients (9.1%) had a detectable relapse of viral RNA in sputum within two weeks of their discharge from the hospital. One patient had persistent viral RNA for 59 days or longer. The median (IQR) seroconversion time of anti-S IgM, anti-RBD IgM, and anti-N IgM was 10.5 (7.75-15.5) days, 14 (9-24) days, and 10 (7-14) days, respectively. The median (IQR) seroconversion time of anti-S IgG, anti-RBD IgG, and anti-N IgG was 10 (7.25-16.5) days, 13 (9-17) days, and 10 (7-14) days, respectively. By week 8 after symptom onset, IgM were negative in many of the previously positive patients, and IgG levels remained less than 50% of the peak levels in more than 20% of the patients. In about 40% of the patients, anti-RBD IgG levels were 4-times higher in convalescence than in acute phase. SARS-CoV-2 RNA coexisted with antibodies for more than 50 days. Anti-RBD IgM and IgG levels, including anti-RBD IgM levels at presentation and peak time, were significantly higher in viral RNA short persistence patients than in long persistence patients. CONCLUSION This study adds important new information about the features of viral load and antibody dynamics of SARS-CoV-2. It is clear from these results that the viral RNA persists in sputum and stool specimens for a relatively long time in many patients. Anti-RBD may also serve as a potential protective antibody against SARS-CoV-2 infection, as viral persistence appears to be related to anti-RBD levels. Earlier treatment intervention also appears to be a factor in viral persistence.

positive: SARS-CoV-2 infection induces germinal center responses with robust stimulation of CD4 T follicular helper cells in rhesus macaques CD4 T follicular helper (Tfh) cells are important for the generation of long-lasting and specific humoral protection against viral infections. The degree to which SARS-CoV-2 infection generates Tfh cells and stimulates the germinal center response is an important question as we investigate vaccine options for the current pandemic. Here we report that, following infection with SARS-CoV-2, adult rhesus macaques exhibited transient accumulation of activated, proliferating Tfh cells in their peripheral blood on a transitory basis. The CD4 helper cell responses were skewed predominantly toward a Th1 response in blood, lung, and lymph nodes, reflective of the interferon-rich cytokine environment following infection. We also observed the generation of germinal center Tfh cells specific for the SARS-CoV-2 spike (S) and nucleocapsid (N) proteins, and a corresponding early appearance of antiviral serum IgG antibodies but delayed or absent IgA antibodies. Our data suggest that a vaccine promoting Th1-type Tfh responses that target the S protein may lead to protective immunity.

positive: Innate immunity in COVID-19 patients mediated by NKG2A receptors, and potential treatment using Monalizumab, Cholroquine, and antiviral agents Following the outbreak of a novel coronavirus (SARS-CoV-2), studies suggest that the resultant disease (COVID-19) is more severe in individuals with a weakened immune system. Cytotoxic T-cells (CTLs) and Natural Killer (NK) cells are required to generate an effective immune response against viruses, functional exhaustion of which enables disease progression. Patients with severe COVID-19 present significantly lower lymphocyte, and higher neutrophil, counts in blood. Specifically, CD8+ lymphocytes and NK cells were significantly reduced in cases of severe infection compared to patients with mild infection and healthy individuals. The NK group 2 member A (NKG2A) receptor transduces inhibitory signalling, suppressing NK cytokine secretion and cytotoxicity. Overexpression of NKG2A has been observed on CD8+ and NK cells of COVID-19 infected patients compared to healthy controls, while NKG2A overexpression also functionally exhausts CD8+ cells and NK cells, resulting in a severely compromised innate immune response. Blocking NKG2A on CD8+ cells and NK cells in cancers modulated tumor growth, restoring CD8+ T and NK cell function. A recently proposed mechanism via which SARS-CoV-2 overrides innate immune response of the host is by over-expressing NKG2A on CD+ T and NK cells, culminating in functional exhaustion of the immune response against the viral pathogen. Monalizumab is an inhibiting antibody against NKG2A which can restore the function of CD8 + T and NK cells in cancers, successfully ceasing tumor progression with no significant side effects in Phase 2 clinical trials. We hypothesize that patients with severe COVID-19 have a severely compromised innate immune response and could be treated via the use of Monalizumab, interferon α, chloroquine, and other antiviral agents.

positive: SARS-CoV-2 antibody testing-questions to be asked Severe acute respiratory syndrome coronavirus 2 infection and development of coronavirus disease 2019 presents a major health care challenge of global dimensions. Laboratory diagnostics of infected patients, and the assessment of immunity against severe acute respiratory syndrome coronavirus 2, presents a major cornerstone in handling the pandemic. Currently, there is an increase in demand for antibody testing and a large number of tests are already marketed or are in the late stage of development. However, the interpretation of test results depends on many variables and factors, including sensitivity, specificity, potential cross-reactivity and cross-protectivity, the diagnostic value of antibodies of different isotypes, and the use of antibody testing in identification of acutely ill patients or in epidemiological settings. In this article, the recently established COVID-19 Task Force of the German Society for Clinical Chemistry and Laboratory Medicine (DGKL) addresses these issues on the basis of currently available data sets in this rapidly moving field.

positive: Evidence for Cross-Protection Against Subsequent Febrile Respiratory Illness Episodes From Prior Infections by Different Viruses Among Singapore Military Recruits 2009–2014 BACKGROUND: Few studies have evaluated the relative cross-protection conferred by infection with different groups of viruses through studies of sequential infections in humans. We investigated the presence of short-lived relative cross-protection conferred by specific prior viral infections against subsequent febrile respiratory illness (FRI). METHODS: Men enlisted in basic military training between December 2009 and December 2014 were recruited, with the first FRI as the study entry point. ResPlex II assays and real-time polymerase chain reaction assays were used to detect viral pathogens in nasal wash samples, and survival analyses were performed to determine whether infection with particular viruses conferred short-lived relative cross-protection against FRI. RESULTS: Prior infection with adenovirus (hazard ratio [HR], 0.24; 95% confidence interval [CI], .14–.44) or influenza virus (HR, 0.52; 95% CI, .38–.73) conferred relative protection against subsequent FRI episode. Results were statistically significant even after adjustment for the interval between enlistment and FRI (P < .001). Adenovirus-positive participants with FRI episodes tended to be protected against subsequent infection with adenovirus, coronavirus, enterovirus/rhinovirus, and influenza virus (P = .062–.093), while men with influenza virus–positive FRI episodes tended be protected against subsequent infection with adenovirus (P = .044) and influenza virus (P = .081). CONCLUSION: Prior adenovirus or influenza virus infection conferred cross-protection against subsequent FRI episodes relative to prior infection due to other circulating viruses.

positive: COVID-19 coronavirus vaccine design using reverse vaccinology and machine learning To ultimately combat the emerging COVID-19 pandemic, it is desired to develop an effective and safe vaccine against this highly contagious disease caused by the SARS-CoV-2 coronavirus. Our literature and clinical trial survey showed that the whole virus, as well as the spike (S) protein, nucleocapsid (N) protein, and membrane protein, have been tested for vaccine development against SARS and MERS. We further used the Vaxign reverse vaccinology tool and the newly developed Vaxign-ML machine learning tool to predict COVID-19 vaccine candidates. The N protein was found to be conserved in the more pathogenic strains (SARS/MERS/COVID-19), but not in the other human coronaviruses that mostly cause mild symptoms. By investigating the entire proteome of SARS-CoV-2, six proteins, including the S protein and five non-structural proteins (nsp3, 3CL-pro, and nsp8–10) were predicted to be adhesins, which are crucial to the viral adhering and host invasion. The S, nsp3, and nsp8 proteins were also predicted by Vaxign-ML to induce high protective antigenicity. Besides the commonly used S protein, the nsp3 protein has not been tested in any coronavirus vaccine studies and was selected for further investigation. The nsp3 was found to be more conserved among SARS-CoV-2, SARS-CoV, and MERS-CoV than among 15 coronaviruses infecting human and other animals. The protein was also predicted to contain promiscuous MHC-I and MHC-II T-cell epitopes, and linear B-cell epitopes localized in specific locations and functional domains of the protein. Our predicted vaccine targets provide new strategies for effective and safe COVID-19 vaccine development.

positive: SARS-CoV-2-specific T cells exhibit unique features characterized by robust helper function, lack of terminal differentiation, and high proliferative potential Convalescing COVID-19 patients mount robust T cell responses against SARS-CoV-2, suggesting an important role for T cells in viral clearance. To date, the phenotypes of SARS-CoV-2-specific T cells remain poorly defined. Using 38-parameter CyTOF, we phenotyped longitudinal specimens of SARS-CoV-2-specific CD4+ and CD8+ T cells from four individuals who recovered from mild COVID-19. SARS-CoV-2-specific CD4+ T cells were exclusively Th1 cells, and predominantly Tcm with phenotypic features of robust helper function. SARS-CoV-2-specific CD8+ T cells were predominantly atypical Temra cells in a state of less terminal differentiation and therefore capable of expansion. Subsets of SARS-CoV-2-specific T cells exhibit features of being long-lived and capable of homeostatic proliferation consistent with their persistence for over two months. Our results suggest that long-lived and robust T cell immunity is generated following natural SARS-CoV-2 infection, and support an important role for SARS-CoV-2-specific T cells in host control of COVID-19.

positive: The starting line for COVID-19 vaccine development

positive: SARS-Cov-2 infection: response of human immune system and possible implications for the rapid test and treatment Abstract The new coronavirus outbreak is an ongoing pandemic that is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The new coronavirus SARS-Cov-2 belongs to the subfamily of β−coronaviruses and shares 79.5% of the genetic sequence of SARS-CoV, the causative agent of the epidemic that started in 2002 and ended in 2004. Considering the clinical impact of the new outbreak, it is highly important to study the potential responses of the human immune system during the SARS-CoV-2 infection as well as the role of virus-specific T cells and by B-lymphocytes. Moreover, specific data on the production of IgG and IgM is crucial to allow the rapid identification of the infection. In this paper we also described the importance of sensitive and specific rapid test for SARS-CoV-2. Indeed, this test represents an important immunological tool aimed at identifying the precise phase of the infection in order to undertake a more appropriate pharmacological treatment. Lastly, we provided an overview of pharmacological treatments aimed to reduce inflammatory processes underlying the infection and the need for the discovery of a new vaccine against SARS-CoV-2.

positive: Antibody responses to SARS-CoV-2 in patients of novel coronavirus disease 2019 Summary Background The novel coronavirus SARS-CoV-2 is a newly emerging virus. The antibody response in infected patient remains largely unknown, and the clinical values of antibody testing have not been fully demonstrated. Methods A total of 173 patients with confirmed SARS-CoV-2 infection were enrolled. Their serial plasma samples (n = 535) collected during the hospitalization period were tested for total antibodies (Ab), IgM and IgG against SARS-CoV-2 using immunoassays. The dynamics of antibodies with the progress and severity of disease was analyzed. Findings Among 173 patients, the seroconversion rate for Ab, IgM and IgG was 93.1% (161/173), 82.7% (143/173) and 64.7% (112/173), respectively. Twelve patients who had not seroconverted were those only blood samples at the early stage of illness were collected. The seroconversion sequentially appeared for Ab, IgM and then IgG, with a median time of 11, 12 and 14 days, respectively. The presence of antibodies was < 40% among patients in the first 7 days of illness, and then rapidly increased to 100.0%, 94.3% and 79.8% for Ab, IgM and IgG respectively since day 15 after onset. In contrast, the positive rate of RNA decreased from 66.7% (58/87) in samples collected before day 7 to 45.5% (25/55) during days 15 to 39. Combining RNA and antibody detections significantly improved the sensitivity of pathogenic diagnosis for COVID-19 patients (p < 0.001), even in early phase of 1-week since onset (p = 0.007). Moreover, a higher titer of Ab was independently associated with a worse clinical classification (p = 0.006). Interpretation The antibody detection offers vital clinical information during the course of SARS-CoV-2 infection. The findings provide strong empirical support for the routine application of serological testing in the diagnosis and management of COVID-19 patients.

positive: SARS Coronavirus Pathogenesis and Therapeutic Treatment Design Emerging pathogens are either new or newly recognized or those that are increasing in incidence and spread. Since the identity of emerging pathogens from animal reservoirs is difficult to predict, the development for pathogen-specific therapeutics and vaccines is problematic. The highly pathogenic SARS coronavirus (SARS-CoV) emerged from zoonotic pools in 2002 to cause a global epidemic of severe acute respiratory syndrome (SARS). Many patients with SARS-CoV experienced an exacerbated form of disease called acute respiratory distress syndrome (ARDS) requiring mechanical ventilation and supplemental oxygen and half of these patients died. Similar to other viral pathogens like influenza and West Nile Virus, the severity of SARS-CoV disease increased with age. Unfortunately, successful vaccination in the most vulnerable populations is a difficult task because of immunological deficiencies associated with aging (immune senescence). Due to the rapidity of virus emergence, technologies like synthetic biology can be harnessed to facilitate rapid recombinant virus construction for studying the novel virus biology, pathogenesis and the evaluation of therapeutic interventions. Since predicting the antigenic identity of future emergence is difficult, candidate vaccines and therapeutics should have a maximal breadth of cross-protection, and panels of antigenically divergent synthetically reconstructed viruses can be used as tools for this evaluation. We discuss how synthetic reconstruction of many animal and human SARS-CoV has provided a model to study the molecular mechanisms governing emergence and pathogenesis of viral diseases. In addition, we review the evolution, epidemiology, and pathogenesis of epidemic and zoonotic SARS-CoV with focus on the development of broadly reactive therapeutics and vaccines that protect aged populations from the zoonotic pool.

positive: Scrutinizing the SARS-CoV-2 protein information for the designing an effective vaccine encompassing both the T-cell and B-cell epitopes Novel SARS coronavirus (SARS-CoV-2) has caused a pandemic condition world-wide and has been declared as public health emergency of International concern by WHO in a very short span of time. The community transmission of this highly infectious virus has severely affected various parts of China, Italy, Spain and USA among others. The prophylactic solution against SARS-CoV-2 infection is challenging due to the high mutation rate of its RNA genome. Herein, we exploited a next generation vaccinology approach to construct a multi-epitope vaccine candidate against SARS-CoV-2 with high antigenicity, safety and efficacy to combat this deadly infectious agent. The whole proteome was scrutinized for the screening of highly conserved, antigenic, non-allergen and non-toxic epitopes having high population coverage that can elicit both humoral and cellular mediated immune response against COVID-19 infection. These epitopes along with four different adjuvants were utilized to construct a multi-epitope vaccine candidate that can generate strong immunological memory response having high efficacy in humans. Various physiochemical analyses revealed the formation of a stable vaccine product having a high propensity to form a protective solution against the detrimental SARS-CoV-2 strain with high efficacy. The vaccine candidate interacted with immunological receptor TLR3 with high affinity depicting the generation of innate immunity. Further, the codon optimization and in silico expression show the plausibility of the high expression and easy purification of the vaccine product. Thus, this present study provides an initial platform of the rapid generation of an efficacious protective vaccine for combating COVID-19.

positive: DNA vaccines: prime time is now Recently newer synthetic DNA vaccines have been rapidly advanced to clinical study and have demonstrated an impressive degree of immune potency and tolerability. Improvements in DNA delivery over prior needle and syringe approaches include jet delivery, gene gun delivery, among others. Among the most effective of these new delivery methods, advanced electroporation (EP), combined with other advances, induces robust humoral and cellular immunity in both preventative as well as therapeutic studies. Advancements in the design of the DNA inserts include leader sequence changes, RNA and codon optimizations, improved insert designs, increased concentrations of DNA, and skin delivery, appear to complement newer delivery strategies. These advances also provide a framework for the in vivo production of synthetic DNA biologics. In this review, we focus on recent studies of synthetic DNA vaccines in the clinic for the prevention or treatment of infectious diseases with a focus on adaptive electroporation for delivery, and briefly summarize novel preclinical data advancing the in vivo delivery of DNA-encoded antibody-like biologics.

positive: SARS‐CoV‐2 infection‐induced immune responses: friends or foes? Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) is an emerging coronavirus that belongs to the β genus, causing the outbreak of coronavirus disease 19 (COVID‐19). SARS‐CoV‐2 infection can stimulate a pronounced immune response in the host, which embodies in the decrease of lymphocytes and aberrant increase of cytokines in COVID‐19 patients. SARS‐CoV‐2 RNA and proteins interact with various pattern recognition receptors that switch on antiviral immune responses to regulate viral replication and spreading within the host in vivo. However, overactive and impaired immune responses also cause immune damage and subsequent tissue inflammation. This article focuses on the dual roles of immune system during SARS‐CoV‐2 infection, providing a theoretical basic for identifying therapeutic targets in a situation with an unfavorable immune reaction.

positive: Protection from SARS coronavirus conferred by live measles vaccine expressing the spike glycoprotein Abstract The recent identification of a novel human coronavirus responsible of a SARS-like illness in the Middle-East a decade after the SARS pandemic, demonstrates that reemergence of a SARS-like coronavirus from an animal reservoir remains a credible threat. Because SARS is contracted by aerosolized contamination of the respiratory tract, a vaccine inducing mucosal long-term protection would be an asset to control new epidemics. To this aim, we generated live attenuated recombinant measles vaccine (MV) candidates expressing either the membrane-anchored SARS-CoV spike (S) protein or its secreted soluble ectodomain (Ssol). In mice susceptible to measles virus, recombinant MV expressing the anchored full-length S induced the highest titers of neutralizing antibodies and fully protected immunized animals from intranasal infectious challenge with SARS-CoV. As compared to immunization with adjuvanted recombinant Ssol protein, recombinant MV induced stronger and Th1-biased responses, a hallmark of live attenuated viruses and a highly desirable feature for an antiviral vaccine.

positive: Cross-reaction of sera from COVID-19 patients with SARS-CoV assays. Background: The SARS-CoV-2 shares 74.5% genome identity with SARS-CoV, both exhibiting a similar well conserved structure. Therefore, antibodies produced in COVID-19 and SARS patients should not be that dissimilar. We evaluated SARS-CoV test assays to detect for the presence of antibodies to SARS-CoV-2 and tried to determine the timing of appearance of these antibodies by testing serial sera from these patients. Methods: Tests were carried out using ELISA (total antibodies) and indirect immunofluorescence (IIFA) (IgM & IgG) methods on serial sera from patients confirmed with SARS-CoV-2 infection. Results: Cross-reactivity was seen in these two test assays with sera from COVID-19 patients and was detected in 6 out of 7 patients from 7 days after onset of symptoms. Five of the patients had detectable antibodies by the 3rd week into their illness and there was evidence of seroconversion in 4 patients. The IIFA method was marginally more sensitive compared to the ELISA assay, however the IIFA IgM test was not useful in the early phase of the illness with poor sensitivity. Conclusions: Existing diagnostic assays for SARS-CoV can detect antibodies in patients who were diagnosed with COVID-19. These assays maybe be utilized as an interim measure in epidemiological investigations for contact tracing and to determine the extent of community spread of this new emerging virus pending the availability of specific serology tests for SARS-CoV-2.

positive: Analysis of Serologic Cross-Reactivity Between Common Human Coronaviruses and SARS-CoV-2 Using Coronavirus Antigen Microarray The current practice for diagnosis of SARS-CoV-2 infection relies on PCR testing of nasopharyngeal or respiratory specimens in a symptomatic patient at high epidemiologic risk. This testing strategy likely underestimates the true prevalence of infection, creating the need for serologic methods to detect infections missed by the limited testing to date. Here, we describe the development of a coronavirus antigen microarray containing immunologically significant antigens from SARS-CoV-2, in addition to SARS-CoV, MERS-CoV, common human coronavirus strains, and other common respiratory viruses. A preliminary study of human sera collected prior to the SARS-CoV-2 pandemic demonstrates overall high IgG reactivity to common human coronaviruses and low IgG reactivity to epidemic coronaviruses including SARS-CoV-2, with some cross-reactivity of conserved antigenic domains including S2 domain of spike protein and nucleocapsid protein. This array can be used to answer outstanding questions regarding SARS-CoV-2 infection, including whether baseline serology for other coronaviruses impacts disease course, how the antibody response to infection develops over time, and what antigens would be optimal for vaccine development.

positive: Detection of antibodies to the SARS-CoV-2 spike glycoprotein in both serum and saliva enhances detection of infection BACKGROUND: Detecting antibody responses during and after SARS-CoV-2 infection is essential in determining the seroepidemiology of the virus and the potential role of antibody in disease. Scalable, sensitive and specific serological assays are essential to this process. The detection of antibody in hospitalized patients with severe disease has proven straightforward; detecting responses in subjects with mild disease and asymptomatic infections has proven less reliable. We hypothesized that the suboptimal sensitivity of antibody assays and the compartmentalization of the antibody response may contribute to this effect. METHODS: We systemically developed an ELISA assay, optimising different antigens and amplification steps, in serum and saliva from symptomatic and asymptomatic SARS-CoV-2-infected subjects. RESULTS: Using trimeric spike glycoprotein, rather than nucleocapsid enabled detection of responses in individuals with low antibody responses. IgG1 and IgG3 predominate to both antigens, but more antispike IgG1 than IgG3 was detectable. All antigens were effective for detecting responses in hospitalized patients. Anti-spike, but not nucleocapsid, IgG, IgA and IgM antibody responses were readily detectable in saliva from non-hospitalized symptomatic and asymptomatic individuals. Antibody responses in saliva and serum were largely independent of each other and symptom reporting. CONCLUSIONS. Detecting antibody responses in both saliva and serum is optimal for determining virus exposure and understanding immune responses after SARS-CoV-2 infection. FUNDING. This work was funded by the University of Birmingham, the National Institute for Health Research (UK), the NIH National Institute for Allergy and Infectious Diseases, the Bill and Melinda Gates Foundation and the University of Southampton.

positive: Serologic responses to SARS-CoV-2 infection among hospital staff with mild disease in eastern France Background: The serologic response of individuals with mild forms of SARS-CoV-2 infection is poorly characterized. Methods: Hospital staff who had recovered from mild forms of PCR-confirmed SARS-CoV-2 infection were tested for anti-SARS-CoV-2 antibodies using three assays: a LuLISA targeting the N protein (99% specificity), a rapid immunodiagnostic test (99.4% specificity), and a S- Flow assay (>99.5% specificity). The neutralizing activity of the sera was tested with a pseudovirus-based assay. Results: Of 162 hospital staff who participated in the investigation, 160 reported SARS-CoV- 2 infection that had not required hospital admission and were included in these analyses. The median time from symptom onset to blood sample collection was 24 days (IQR: 21-28, range 13-39). The LuLISA N assay detected antibodies in 129 (80.6%) of the samples, with better performance for samples collected after 28 days (45/48 = 93.8%); the rapid immunodiagnostic test in 153 (95.6%); and the S-Flow assay in 159 (99.4%), failing to detect antibodies in one sample collected 18 days after symptom onset (none of the other tests detected antibodies in that patient). Neutralizing antibodies (NAbs) were detected in 79%, 92% and 98% of samples collected 13-20, 21-27 and 28-41 days after symptom onset, respectively (P=0.02). Conclusion: Antibodies against SARS-CoV-2 were detected in virtually all hospital staff after 13 days from the COVID-19 symptom onset. This finding supports the use of serologic testing for the diagnosis of individuals who have recovered from SARS-CoV-2 infection. The neutralizing activity of the antibodies increased overtime. Future studies will help assess the persistence of the humoral response and its associated neutralization capacity in recovered patients.

positive: D614G Spike Variant Does Not Alter IgG, IgM, or IgA Spike Seroassay Performance Emergence of a new variant of spike protein (D614G) with increased infectivity and transmissibility has prompted many to analyze the potential role of this variant in the SARS-CoV-2 pandemic. When a new variant emerges, there is a concern regarding whether an individual exposed to one variant of a virus will have cross-reactive immune memory to the second variant. Accordingly, we analyzed the serologic reactivity of D614 (original) and G614 variant spike proteins. We found that antibodies from a high-incidence population in New York City reacted both toward the original D614 spike and the G614 spike variant. These data suggest that patients who have been exposed to either SARS-CoV-2 variant have humoral immunity that can respond against both variants. This is an important finding both for SARS-CoV-2 disease biology and for potential antibody-based therapeutics.

positive: B-cell responses in patients who have recovered from severe acute respiratory syndrome target a dominant site in the S2 domain of the surface spike glycoprotein. Severe acute respiratory syndrome (SARS) is a recently emerged infectious disease caused by a novel strain of coronavirus. Examination of the immune responses of patients who have recovered from SARS should provide important information for design of a safe and effective vaccine. We determined the continuous viral epitopes targeted by antibodies in plasma samples from convalescent SARS patients through biopanning with a vast M13 phage display dodecapeptide library. These epitopes converged to very short peptide fragments, one on each of the structural proteins spike and nucleocapsid and the nonstructural proteins 3a, 9b, and nsp 3. Immunoassays found that most of the patients who had recovered from SARS developed complementary antibodies to the epitope-rich region on the spike S2 protein, indicating that this is an immunodominant site on the viral envelope comprising the spike, matrix, and small envelope glycoproteins. These S2-targeting antibodies were shown to effectively neutralize the coronavirus, indicating that they provided protective immunity to help the patients recover from the viral infection. These results suggest that the SARS coronavirus might have an antigenic profile distinct from those of other human or animal coronaviruses. Due to the tested safety and protective effects of the convalescent-phase serological antibodies, identification of their complementary antigens may enable the design of an epitope-based vaccine to prevent potential antibody-mediated immunopathology.

positive: The Challenges of Vaccine Development against a New Virus during a Pandemic The rapid emergence of a highly pathogenic, readily transmissible coronavirus has resulted in a global pandemic, affecting millions and destabilizing economies. This catastrophe triggered a clarion call for the immediate deployment of a protective vaccine. We describe the unique challenges of developing a vaccine against SARS-CoV-2 in a pandemic setting.

positive: SARS-CoV-2 Vaccines: Status Report SARS-CoV-2, the causal agent of COVID-19, first emerged in late 2019 in China. It has since infected more than 870,000 individuals and caused more than 43,000 deaths globally. Here, we discuss therapeutic and prophylactic interventions for SARS-CoV-2 with a focus on vaccine development and its challenges. Vaccines are being rapidly developed but will likely come too late to affect the first wave of a potential pandemic. Nevertheless, critical lessons can be learned for the development of vaccines against rapidly emerging viruses. Importantly, SARS-CoV-2 vaccines will be essential to reducing morbidity and mortality if the virus establishes itself in the population.

positive: Memory T cell responses targeting the SARS coronavirus persist up to 11 years post-infection Severe acute respiratory syndrome (SARS) is a highly contagious infectious disease which first emerged in late 2002, caused by a then novel human coronavirus, SARS coronavirus (SARS-CoV). The virus is believed to have originated from bats and transmitted to human through intermediate animals such as civet cats. The re-emergence of SARS-CoV remains a valid concern due to the continual persistence of zoonotic SARS-CoVs and SARS-like CoVs (SL-CoVs) in bat reservoirs. In this study, the screening for the presence of SARS-specific T cells in a cohort of three SARS-recovered individuals at 9 and 11 years post-infection was carried out, and all memory T cell responses detected target the SARS-CoV structural proteins. Two CD8(+) T cell responses targeting the SARS-CoV membrane (M) and nucleocapsid (N) proteins were characterized by determining their HLA restriction and minimal T cell epitope regions. Furthermore, these responses were found to persist up to 11 years post-infection. An absence of cross-reactivity of these CD8(+) T cell responses against the newly-emerged Middle East respiratory syndrome coronavirus (MERS-CoV) was also demonstrated. The knowledge of the persistence of SARS-specific celullar immunity targeting the viral structural proteins in SARS-recovered individuals is important in the design and development of SARS vaccines, which are currently unavailable.

positive: Potent human neutralizing antibodies elicited by SARS-CoV-2 infection The pandemic caused by emerging coronavirus SARS-CoV-2 presents a serious global public health emergency in urgent need of prophylactic and therapeutic interventions. SARS-CoV-2 cellular entry depends on binding between the viral Spike protein receptor-binding domain (RBD) and the angiotensin converting enzyme 2 (ACE2) target cell receptor. Here, we report on the isolation and characterization of 206 RBD-specific monoclonal antibodies (mAbs) derived from single B cells of eight SARS-CoV-2 infected individuals. These mAbs come from diverse families of antibody heavy and light chains without apparent enrichment for particular families in the repertoire. In samples from one patient selected for further analyses, we found coexistence of germline and germline divergent clones. Both clone types demonstrated impressive binding and neutralizing activity against pseudovirus and live SARS-CoV-2. However, the antibody neutralizing potency is determined by competition with ACE2 receptor for RBD binding. Surprisingly, none of the SARS-CoV-2 antibodies nor the infected plasma cross-reacted with RBDs from either SARS-CoV or MERS-CoV although substantial plasma cross-reactivity to the trimeric Spike proteins from SARS-CoV and MERS-CoV was found. These results suggest that antibody response to RBDs is viral species-specific while that cross-recognition target regions outside the RBD. The specificity and neutralizing characteristics of this plasma cross-reactivity requires further investigation. Nevertheless, the diverse and potent neutralizing antibodies identified here are promising candidates for prophylactic and therapeutic SARS-CoV-2 interventions.

positive: Validation and Performance Comparison of Three SARS-CoV-2 Antibody Assays Serology testing of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is increasingly being used during the current pandemic of Coronavirus Disease 2019 (COVID-19). The clinical and epidemiologic utilities of antibody-based SARS-CoV-2 testing are under debate. Characterizing these assays helps to understand the disease and provides scientific basis for deciding how to best use these assays. The study assessed one chemiluminescent assay (Abbott COVID-2 IgG) and two lateral flow assays (STANDARD Q [SQ] IgM/IgG Duo and Wondfo Total Antibody Test). Validation included 113 blood samples from 71 PCR-confirmed COVID-19 patients and 1182 samples from negative controls with potential interferences/cross-reactions, including 1063 pre-pandemic samples. IgM antibodies against SARS-CoV-2 were detected as early as post-symptom onset days 3-4. IgG antibodies were first detected post-onset days 5-6 by SQ assays. The detection rates increased gradually, and SQ IgG, Abbott IgG and Wondfo Total detected antibodies from all the PCR-confirmed patients 14 days after symptom onset. Overall agreements between SQ IgM/IgG and Wondfo Total was 88.5% and between SQ IgG and Abbott IgG was 94.6% (Kappa = 0.75, 0.89). No cross-reaction with other endemic coronavirus infections were identified. Viral hepatitis and autoimmune samples were the main cross-reactions observed. However, the interferences/cross-reactions were low. The specificities were 100% for SQ IgG and Wondfo Total and 99.62% for Abbott IgG and 98.87% for SQ IgM. These findings demonstrate high sensitivity and specificity of appropriately validated antibody-based SARS-CoV-2 assays with implications for clinical use and epidemiological seroprevalence studies.

positive: Expected immune recognition of COVID-19 virus by memory from earlier infections with common coronaviruses in a large part of the world population SARS-CoV-2 is the coronavirus agent of the COVID-19 pandemic causing high mortalities. In contrast, the widely spread human coronaviruses OC43, HKU1, 229E, and NL63 tend to cause only mild symptoms. The present study shows, by in silico analysis, that these common human viruses are expected to induce immune memory against SARS-CoV-2 by sharing protein fragments (antigen epitopes) for presentation to the immune system by MHC class I. A list of such epitopes is provided. The number of these epitopes and the prevalence of the common coronaviruses suggest that a large part of the world population has some degree of specific immunity against SARS-CoV-2 already, even without having been infected by that virus. For inducing protection, booster vaccinations enhancing existing immunity are less demanding than primary vaccinations against new antigens. Therefore, for the discussion on vaccination strategies against COVID-19, the available immune memory against related viruses should be part of the consideration.

positive: Effect of specific humoral immunity and some non-specific factors on resistance of volunteers to respiratory coronavirus infection. Thirty-three volunteers were inoculated intranasally with coronavirus 229 E, and their responses monitored by antibody rises, symptomatology and virus excretion. These were related to their pre-trial immune status as indicated by concentrations of specific antibodies and non-specific proteins in serum and nasal washings. Both circulating and local specific antibodies were associated with protection from infection and disease, but only specific IgA antibodies of either type appeared to shorten the period of virus shedding. Although total secretory IgA was significantly associated only with reduction of symptoms, total protein in nasal washings appeared to protect against infection also, indicating that other locally produced proteins, not identified, may be associated with resistance. Two of the many factors which may affect the concentration of circulating and local protective proteins and thus influence the outcome of virus inoculation, namely, sex of the volunteer and the interval since the previous cold, were examined. Male volunteers or volunteers who had had evidence of a recent respiratory infection were less likely to be infected, but if they were infected, they had lower clinical scores and stopped shedding virus earlier than the rest. These groups possessed higher concentrations of specific antibodies and non-specific proteins in their pre-challenge sera and/or nasal washings. The significance of these findings is discussed.

positive: Clinical, molecular and epidemiological characterization of the SARS-CoV2 virus and the Coronavirus disease 2019 (COVID-19), a comprehensive literature review Abstract Coronaviruses are an extensive family of viruses that can cause disease in both animals and humans. The current classification of coronaviruses recognizes 39 species in 27 subgenera that belong to the family Coronaviridae. From those, at least seven coronaviruses are known to cause respiratory infections in humans. Four of these viruses can cause common cold-like symptoms. Those that infect animals can evolve and become infectious to humans. Three recent examples of these viral jumps include SARS CoV, MERS-CoV and SARS CoV-2 virus. They are responsible for causing severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS) and the most recently discovered coronavirus disease during 2019 (COVID-19). COVID-19, a respiratory disease caused by the SARS-CoV-2 virus, was declared a pandemic by the World Health Organization (WHO) on 11 March 2020. The rapid spread of the disease has taken the scientific and medical community by surprise. Latest figures from 20th May 2020 show more than 5 million people had been infected with the virus, causing more than 330,000 deaths in over 210 countries worldwide. The large amount of information received daily relating to COVID-19 is so abundant and dynamic that medical staff, health authorities, academics and the media are not able to keep up with this new pandemic. In order to offer a clear insight of the extensive literature available, we have conducted a comprehensive literature review of the SARS CoV-2 Virus and the Coronavirus Diseases 2019 (COVID-19).

positive: Adenoviral expression of a truncated S1 subunit of SARS-CoV spike protein results in specific humoral immune responses against SARS-CoV in rats Abstract The causative agent of severe acute respiratory syndrome (SARS) has been identified as SARS-associated coronavirus (SARS-CoV), but the prophylactic treatment of SARS-CoV is still under investigation. We constructed a recombinant adenovirus containing a truncated N-terminal fragment of the SARS-CoV Spike (S) gene (from −45 to 1469, designated Ad-SN), which encoded a truncated S protein (490 amino-acid residues, a part of 672 amino-acid S1 subunit), and investigated whether this construct could induce effective immunity against SARS-CoV in Wistar rats. Rats were immunized either subcutaneously or intranasally with Ad-SN once a week for three consecutive weeks. Our results showed that all of the immunized animals generated humoral immunity against the SARS-CoV spike protein, and the sera of immunized rats showed strong capable of protecting from SARS-CoV infection in vitro. Histopathological examination did not find evident side effects in the immunized animals. These results indicate that an adenoviral-based vaccine carrying an N-terminal fragment of the Spike gene is able to elicit strong SARS-CoV-specific humoral immune responses in rats, and may be useful for the development of a protective vaccine against SARS-CoV infection.

positive: The immune system of children: the key to understanding SARS-CoV-2 susceptibility?

positive: When to relax a lockdown? A modelling-based study of testing-led strategies coupled with sero-surveillance against SARS-CoV-2 infection in India India's lockdown against SARS-CoV-2, if lifted without any other mitigations in place, could risk a second wave of infection. A test-and-isolate strategy, using PCR diagnostic tests, could help to minimise the impact of this second wave. Meanwhile, population-level serological surveillance can provide valuable insights into the level of immunity in the population. Using a mathematical model, consistent with an Indian megacity, we examined how seroprevalence data could guide a test-and-isolate strategy, for lifting a lockdown. For example, if seroprevalence is 20% of the population, we show that a testing strategy needs to identify symptomatic cases within 5 - 8 days of symptom onset, in order to prevent a resurgent wave from overwhelming hospital capacity in the city. This estimate is robust to uncertainty in the effectiveness of the lockdown, as well as in immune protection against reinfection. To set these results in their economic context, we estimate that the weekly cost of such a PCR-based testing programme would be less than 2.1% of the weekly economic loss due to the lockdown. Our results illustrate how PCR-based testing and serological surveillance can be combined to design evidence-based policies, for lifting lockdowns in Indian cities and elsewhere.

positive: Emergence of Novel Coronavirus and COVID-19: whether to stay or die out? The last century has witnessed several assaults from RNA viruses, resulting in millions of death throughout the world. The 21st century appears no longer an exception, with the trend continued with escalated fear of SARS coronavirus in 2002 and further concern of influenza H5N1 in 2003. A novel influenza virus created the first pandemic of the 21st century, the pandemic flu in 2009 preceded with the emergence of another deadly virus, MERS-CoV in 2012. A novel coronavirus “SARS-CoV-2” (and the disease COVID-19) emerged suddenly, causing a rapid outbreak with a moderate case fatality rate. This virus is continuing to cause health care providers grave concern due to the lack of any existing immunity in the human population, indicating their novelty and lack of previous exposure. The big question is whether this novel virus will be establishing itself in an endemic form or will it eventually die out? Endemic viruses during circulation may acquire mutations to infect naïve, as well as individual with pre-existing immunity. Continuous monitoring is strongly advisable, not only to the newly infected individuals, but also to those recovered individuals who were infected by SARS-CoV-2 as re-infection may lead to the selection of escape mutants and subsequent dissemination to the population.

positive: Social Isolation as a Means of Reducing Dysfunctional Coronavirus Anxiety and Increasing Psychoneuroimmunity

positive: Antibodies against trimeric S glycoprotein protect hamsters against SARS-CoV challenge despite their capacity to mediate FcγRII-dependent entry into B cells in vitro Vaccine-induced antibodies can prevent or, in the case of feline infectious peritonitis virus, aggravate infections by coronaviruses. We investigated whether a recombinant native full-length S-protein trimer (triSpike) of severe acute respiratory syndrome coronavirus (SARS-CoV) was able to elicit a neutralizing and protective immune response in animals and analyzed the capacity of anti-S antibodies to mediate antibody-dependent enhancement (ADE) of virus entry in vitro and enhancement of replication in vivo. SARS-CoV-specific serum and mucosal immunoglobulins were readily detected in immunized animals. Serum IgG blocked binding of the S-protein to the ACE2 receptor and neutralized SARS-CoV infection in vitro. Entry into human B cell lines occurred in a FcγRII-dependent and ACE2-independent fashion indicating that ADE of virus entry is a novel cell entry mechanism of SARS-CoV. Vaccinated animals showed no signs of enhanced lung pathology or hepatitis and viral load was undetectable or greatly reduced in lungs following challenge with SARS-CoV. Altogether our results indicate that a recombinant trimeric S protein was able to elicit an efficacious protective immune response in vivo and warrant concern in the safety evaluation of a human vaccine against SARS-CoV.

positive: Severe Acute Respiratory Syndrome Coronavirus 2−Specific Antibody Responses in Coronavirus Disease Patients A new coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has recently emerged to cause a human pandemic. Although molecular diagnostic tests were rapidly developed, serologic assays are still lacking, yet urgently needed. Validated serologic assays are needed for contact tracing, identifying the viral reservoir, and epidemiologic studies. We developed serologic assays for detection of SARS-CoV-2 neutralizing, spike protein–specific, and nucleocapsid-specific antibodies. Using serum samples from patients with PCR-confirmed SARS-CoV-2 infections, other coronaviruses, or other respiratory pathogenic infections, we validated and tested various antigens in different in-house and commercial ELISAs. We demonstrated that most PCR-confirmed SARS-CoV-2–infected persons seroconverted by 2 weeks after disease onset. We found that commercial S1 IgG or IgA ELISAs were of lower specificity, and sensitivity varied between the 2 assays; the IgA ELISA showed higher sensitivity. Overall, the validated assays described can be instrumental for detection of SARS-CoV-2–specific antibodies for diagnostic, seroepidemiologic, and vaccine evaluation studies.

positive: The origin, transmission and clinical therapies on coronavirus disease 2019 (COVID-19) outbreak – an update on the status An acute respiratory disease, caused by a novel coronavirus (SARS-CoV-2, previously known as 2019-nCoV), the coronavirus disease 2019 (COVID-19) has spread throughout China and received worldwide attention. On 30 January 2020, World Health Organization (WHO) officially declared the COVID-19 epidemic as a public health emergency of international concern. The emergence of SARS-CoV-2, since the severe acute respiratory syndrome coronavirus (SARS-CoV) in 2002 and Middle East respiratory syndrome coronavirus (MERS-CoV) in 2012, marked the third introduction of a highly pathogenic and large-scale epidemic coronavirus into the human population in the twenty-first century. As of 1 March 2020, a total of 87,137 confirmed cases globally, 79,968 confirmed in China and 7169 outside of China, with 2977 deaths (3.4%) had been reported by WHO. Meanwhile, several independent research groups have identified that SARS-CoV-2 belongs to β-coronavirus, with highly identical genome to bat coronavirus, pointing to bat as the natural host. The novel coronavirus uses the same receptor, angiotensin-converting enzyme 2 (ACE2) as that for SARS-CoV, and mainly spreads through the respiratory tract. Importantly, increasingly evidence showed sustained human-to-human transmission, along with many exported cases across the globe. The clinical symptoms of COVID-19 patients include fever, cough, fatigue and a small population of patients appeared gastrointestinal infection symptoms. The elderly and people with underlying diseases are susceptible to infection and prone to serious outcomes, which may be associated with acute respiratory distress syndrome (ARDS) and cytokine storm. Currently, there are few specific antiviral strategies, but several potent candidates of antivirals and repurposed drugs are under urgent investigation. In this review, we summarized the latest research progress of the epidemiology, pathogenesis, and clinical characteristics of COVID-19, and discussed the current treatment and scientific advancements to combat the epidemic novel coronavirus.

positive: Coronavirus Pandemic—Therapy and Vaccines The current coronavirus COVID-19 pandemic, which originated in Wuhan, China, has raised significant social, psychological and economic concerns in addition to direct medical issues. The rapid spread of severe acute respiratory syndrome-coronavirus (SARS-CoV)-2 to almost every country on the globe and the failure to contain the infections have contributed to fear and panic worldwide. The lack of available and efficient antiviral drugs or vaccines has further worsened the situation. For these reasons, it cannot be overstated that an accelerated effort for the development of novel drugs and vaccines is needed. In this context, novel approaches in both gene therapy and vaccine development are essential. Previous experience from SARS- and MERS-coronavirus vaccine and drug development projects have targeted glycoprotein epitopes, monoclonal antibodies, angiotensin receptor blockers and gene silencing technologies, which may be useful for COVID-19 too. Moreover, existing antivirals used for other types of viral infections have been considered as urgent action is necessary. This review aims at providing a background of coronavirus genetics and biology, examples of therapeutic and vaccine strategies taken and potential innovative novel approaches in progress.

positive: Estimation of the probability of reinfection with COVID-19 coronavirus by the SEIRUS model With sensitivity of the Polymerase Chain Reaction (PCR) test used to detect the presence of the virus in the human host, the global health community has been able to record a great number of recovered population. Therefore, in a bid to answer a burning question of reinfection in the recovered class, the model equations which exhibits the disease-free equilibrium (E_0 ) state for COVID-19 coronavirus was developed in this study and was discovered to both exist as well as satisfy the criteria for a locally or globally asymptotic stability with a basic reproductive number R_0=0 for and endemic situation. Hence, there is a chance of no secondary reinfections from the recovered population as the rate of incidence of the recovered population vanishes, that is, B=0. Furthermore, numerical simulations were carried to complement the analytical results in investigating the effect of the implementation of quarantine and observatory procedures has on the projection of the further spread of the virus globally. Result shows that the proportion of infected population in the absence of curative vaccination will continue to grow globally meanwhile the recovery rate will continue slowly which therefore means that the ratio of infection to recovery rate will determine the death rate that is recorded globally and most significant for this study is the rate of reinfection by the recovered population which will decline to zero over time as the virus is cleared clinically from the system of the recovered class.

positive: Cross-reactive antibody response between SARS-CoV-2 and SARS-CoV infections Summary The World Health Organization has declared the ongoing outbreak of COVID-19, which is caused by a novel coronavirus SARS-CoV-2, as pandemic. There is currently a lack of knowledge about the antibody response elicited from SARS-CoV-2 infection. One major immunological question concerns antigenic differences between SARS-CoV-2 and SARS-CoV. We address this question by analyzing plasma from patients infected by SARS-CoV-2 or SARS-CoV, and from infected or immunized mice. Our results show that, while cross-reactivity in antibody binding to the spike protein is common, cross-neutralization of the live viruses may be rare, indicating the presence of non-neutralizing antibody response to conserved epitopes in the spike. Whether such low or non-neutralizing antibody response leads to antibody-dependent disease enhancement needs to be addressed in the future. Overall, this study not only addresses a fundamental question regarding antigenicity differences between SARS-CoV-2 and SARS-CoV, but also has implications for immunogen design and vaccine development.

positive: Improving vaccine-induced immunity: Can Baseline Predict Outcome? Abstract Immune signatures measured at baseline and immediately prior to vaccination, may predict the immune response to vaccination. Such pre-vaccine assessment might allow not only population-based, but also more personalized vaccination strategies (‘precision vaccination’). If baseline immune signatures are predictive, the underlying mechanism they reflect may also determine vaccination outcome. Thus, baseline signatures might contribute to identifying interventional targets to be modulated prior to vaccination in order to improve vaccination responses. This concept has the potential to transform vaccination strategies and usher in a new approach to improve global health.

positive: Pre-existing and de novo humoral immunity to SARS-CoV-2 in humans Several related human coronaviruses (HCoVs) are endemic in the human population, causing mild respiratory infections1. Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the etiologic agent of Coronavirus disease 2019 (COVID-19), is a recent zoonotic infection that has quickly reached pandemic spread2,3. Zoonotic introduction of novel coronaviruses is thought to occur in the absence of pre-existing immunity in the target human population. Using diverse assays for detection of antibodies reactive with the SARS-CoV-2 Spike (S) glycoprotein, we demonstrate the presence of pre-existing immunity in uninfected and unexposed humans to the new coronavirus. SARS-CoV-2 S-reactive antibodies, exclusively of the IgG class, were readily detectable by a sensitive flow cytometry-based method in SARS-CoV-2-uninfected individuals with recent HCoV infection and targeted the S2 subunit. In contrast, SARS-CoV-2 infection induced higher titres of SARS-CoV-2 S-reactive IgG antibodies, as well as concomitant IgM and IgA antibodies throughout the observation period of 6 weeks since symptoms onset. HCoV patient sera also variably reacted with SARS-CoV-2 S and nucleocapsid (N), but not with the S1 subunit or the receptor binding domain (RBD) of S on standard enzyme immunoassays. Notably, HCoV patient sera exhibited specific neutralising activity against SARS-CoV-2 S pseudotypes, according to levels of SARS-CoV-2 S-binding IgG and with efficiencies comparable to those of COVID-19 patient sera. Distinguishing pre-existing and de novo antibody responses to SARS-CoV-2 will be critical for serology, seroprevalence and vaccine studies, as well as for our understanding of susceptibility to and natural course of SARS-CoV-2 infection.

positive: Fundamental principles of epidemic spread highlight the immediate need for large-scale serological surveys to assess the stage of the SARS-CoV-2 epidemic The spread of a novel pathogenic infectious agent eliciting protective immunity is typically characterised by three distinct phases: (I) an initial phase of slow accumulation of new infections (often undetectable), (II) a second phase of rapid growth in cases of infection, disease and death, and (III) an eventual slow down of transmission due to the depletion of susceptible individuals, typically leading to the termination of the (first) epidemic wave. Before the implementation of control measures (e.g. social distancing, travel bans, etc) and under the assumption that infection elicits protective immunity, epidemiological theory indicates that the ongoing epidemic of SARS-CoV-2 will conform to this pattern. Here, we calibrate a susceptible-infected-recovered (SIR) model to data on cumulative reported SARS-CoV-2 associated deaths from the United Kingdom (UK) and Italy under the assumption that such deaths are well reported events that occur only in a vulnerable fraction of the population. We focus on model solutions which take into consideration previous estimates of critical epidemiological parameters such as the basic reproduction number (R0), probability of death in the vulnerable fraction of the population, infectious period and time from infection to death, with the intention of exploring the sensitivity of the system to the actual fraction of the population vulnerable to severe disease and death. Our simulations are in agreement with other studies that the current epidemic wave in the UK and Italy in the absence of interventions should have an approximate duration of 2-3 months, with numbers of deaths lagging behind in time relative to overall infections. Importantly, the results we present here suggest the ongoing epidemics in the UK and Italy started at least a month before the first reported death and have already led to the accumulation of significant levels of herd immunity in both countries. There is an inverse relationship between the proportion currently immune and the fraction of the population vulnerable to severe disease. This relationship can be used to determine how many people will require hospitalisation (and possibly die) in the coming weeks if we are able to accurately determine current levels of herd immunity. There is thus an urgent need for investment in technologies such as virus (or viral pseudotype) neutralization assays and other robust assays which provide reliable read-outs of protective immunity, and for the provision of open access to valuable data sources such as blood banks and paired samples of acute and convalescent sera from confirmed cases of SARS-CoV-2 to validate these. Urgent development and assessment of such tests should be followed by rapid implementation at scale to provide real-time data. These data will be critical to the proper assessment of the effects of social distancing and other measures currently being adopted to slow down the case incidence and for informing future policy direction.

positive: Higher prevalence of asymptomatic or mild COVID‐19 in children, claims and clues The current pandemic of COVID-19 has generated many challenging questions for the scientific community, ranging from queries about the origin of the virus to its pathogenesis and clinical management. This article is protected by copyright. All rights reserved.

positive: Modulation of the immune response by Middle East respiratory syndrome coronavirus Coronavirus (CoV) infections are commonly associated with respiratory and enteric disease in humans and animals. In 2012, a new human disease called Middle East respiratory syndrome (MERS) emerged in the Middle East. MERS was caused by a virus that was originally called human coronavirus‐Erasmus Medical Center/2012 but was later renamed as Middle East respiratory syndrome coronavirus (MERS‐CoV). MERS‐CoV causes high fever, cough, acute respiratory tract infection, and multiorgan dysfunction that may eventually lead to the death of the infected individuals. The exact origin of MERS‐CoV remains unknown, but the transmission pattern and evidence from virological studies suggest that dromedary camels are the major reservoir host, from which human infections may sporadically occur through the zoonotic transmission. Human to human transmission also occurs in healthcare facilities and communities. Recent studies on Middle Eastern respiratory continue to highlight the need for further understanding the virus‐host interactions that govern disease severity and infection outcome. In this review, we have highlighted the major mechanisms of immune evasion strategies of MERS‐CoV. We have demonstrated that M, 4a, 4b proteins and Plppro of MERS‐CoV inhibit the type I interferon (IFN) and nuclear factor‐κB signaling pathways and therefore facilitate innate immune evasion. In addition, nonstructural protein 4a (NSP4a), NSP4b, and NSP15 inhibit double‐stranded RNA sensors. Therefore, the mentioned proteins limit early induction of IFN and cause rapid apoptosis of macrophages. MERS‐CoV strongly inhibits the activation of T cells with downregulation of antigen presentation. In addition, uncontrolled secretion of interferon ɣ‐induced protein 10 and monocyte chemoattractant protein‐1 can suppress proliferation of human myeloid progenitor cells.

positive: Evaluation of the EUROIMMUN Anti-SARS-CoV-2 ELISA Assay for detection of IgA and IgG antibodies As the Coronavirus 2019 (COVID-19) pandemic evolves, the development of immunoassays to help determine exposure and potentially predict immunity has become a pressing priority. In this report we present the performance of the EUROIMMUN enzyme-linked immunosorbent assay (ELISA) for semi-quantitative detection of IgA and IgG antibodies in serum and plasma samples using recombinant S1 domain of the SARS-CoV-2 spike protein as antigen. Specimens from patients, with and without COVID-19 infection, were tested at the University of Chicago Clinical Microbiology and Immunology Laboratory. Of 86 samples from COVID-19 PCR-negative patients, including 28 samples positive for common human coronavirus strains, 76 tested negative and 10 tested positive for IgA (88.4% agreement, 95% CI: 79.9–93.6) while 84 tested negative and 2 tested positive for IgG (97.7% agreement, 95% CI: 91.9–99.6). Of 82 samples from COVID-19 PCR-positive patients, 14 tested negative and 68 tested positive for IgA (82.9% agreement, 95% CI: 73.4–89.5) while 27 tested negative and 55 tested positive for IgG (67.1% agreement, 95% CI: 56.3–76.3). Samples collected ≥4 days after positive PCR 38 of 42 (90.5% CI: 77.9–96.2) were positive for IgA, and 42 of 42 (100% 95% CI: 91.6–100) were positive for IgG, respectively. The EUROIMMUN Anti-SARS-CoV-2 ELISA Assay demonstrates good sensitivity for detection of IgA and excellent sensitivity for detection of IgG antibodies from samples collected ≥4 days, after COVID-19 diagnosis by PCR. This assay demonstrated only borderline cross reaction in 2 of the 28 samples from patients with common human coronaviruses infection, types NL63 and OC43.

positive: Antibody Dependent Enhancement Due to Original Antigenic Sin and the Development of SARS Human coronavirus (HCoV) is one of the most common causes of respiratory tract infections throughout the world. Two phenomena observed so far in the development of the SARS-CoV-2 pandemic deserve further attention. First, the relative absence of clinical signs of infections in children, second, the early appearance of IgG in certain patients. From the point of view of immune system physiology, such an early rise of specific IgG is expected in secondary immune responses when memory to a cross-reactive antigen is present, usually from an earlier infection with a coronavirus. It is actually typical for the immune system to respond, to what it already knows, a phenomenon that has been observed in many infections with closely related viruses and has been termed "original antigenic sin." The question then arises whether such cross-reactive antibodies are protective or not against the new virus. The worst scenario would be when such cross-reactive memory antibodies to related coronaviruses would not only be non-protective but even enhance infection and the clinical course. Such a phenomenon of antibody dependent enhancement (ADE) has already been described in several viral infections. Thus, the development of IgG against SARS-CoV-2 in the course of COVID-19 might not be a simple sign of viral clearance and developing protection against the virus. On the contrary, due to cross-reaction to related coronavirus strains from earlier infections, in certain patients IgG might enhance clinical progression due to ADE. The patient's viral history of coronavirus infection might be crucial to the development of the current infection with SARS-CoV-2. Furthermore, it poses a note of caution when treating COVID-19 patients with convalescent sera.

positive: Recombinant Infectious Bronchitis Viruses Expressing Chimeric Spike Glycoproteins Induce Partial Protective Immunity against Homologous Challenge despite Limited Replication In Vivo Vaccination regimes against Infectious bronchitis virus (IBV), which are based on a single virus serotype, often induce insufficient levels of cross-protection against serotypes and two or more antigenically diverse vaccines are used in attempt to provide broader protection. Amino acid differences in the surface protein, spike (S), in particular the S1 subunit, are associated with poor cross-protection. Here, homologous vaccination trials with recombinant IBVs (rIBVs), based on the apathogenic strain, BeauR, were conducted to elucidate the role of S1 in protection. A single vaccination of specific-pathogen-free chickens with rIBV expressing S1 of virulent strains M41 or QX, BeauR-M41(S1) and BeauR-QX(S1), gave incomplete protection against homologous challenge, based on ciliary activity and clinical signs. There could be conformational issues with the spike if heterologous S1 and S2 are linked, suggesting a homologous S2 might be essential. To address this, a homologous vaccination-challenge trial incorporating rIBVs expressing full spike from M41, BeauR-M41(S), and S2 subunit from M41, BeauR-M41(S2) was conducted. All chimeric viruses grew to similar titers in vitro, induced virus-specific partial protective immunity, evident by cellular infiltrations, reductions in viral RNA load in the trachea and conjunctiva and higher serum anti-IBV titers. Collectively, these findings show that vaccination with rIBVs primed the birds for challenge but the viruses were cleared rapidly from the mucosal tissues in the head. Chimeric S1 and S2 viruses did not protect as effectively as BeauR-M41(S) based on ciliary activity and clinical signs. Booster vaccinations and an rIBV with improved in vivo replication may improve the levels of protection. IMPORTANCE Infectious bronchitis virus causes an acute, highly contagious respiratory disease, responsible for significant economic losses to the poultry industry. Amino acid differences in the surface protein, spike (S), in particular the S1 subunit, have been associated with poor cross-protection. Available vaccines give poor cross-protection and rationally designed live attenuated vaccines, based on apathogenic BeauR, could address these. Here, to determine the role of S1 in protection, a series of homologous vaccination trials with rIBVs were conducted. Single vaccinations with chimeric rIBVs induced virus-specific partial protective immunity, characterized by reduction in viral load and serum antibody titers. However, BeauR-M41(S) was the only vaccination to improve the level of protection against clinical signs and the loss of tracheal ciliary activity. Growth characteristics show that all of the rIBVs replicated in vitro to similar levels. Booster vaccinations and an rIBV with improved in vivo replication may improve the levels of protection.

positive: Homologous protein domains in SARS-CoV-2 and measles, mumps and rubella viruses: preliminary evidence that MMR vaccine might provide protection against COVID-19 The COVID-19 disease is one of worst pandemics to sweep the globe in recent times. It is noteworthy that the disease has its greatest impact on the elderly. Herein, we investigated the potential of childhood vaccination, specifically against measles, mumps and rubella (MMR), to identify if this could potentially confer acquired protection over SARS-CoV-2. We identified sequence homology between the fusion proteins of SARS-CoV-2 and measles and mumps viruses. Moreover, we also identified a 29% amino acid sequence homology between the Macro (ADP-ribose-1-phosphatase) domains of SARS-CoV-2 and rubella virus. The rubella Macro domain has surface-exposed conserved residues and is present in the attenuated rubella virus in MMR. Hence, we hypothesize that MMR could protect against poor outcome in COVID-19 infection. As an initial test of this hypothesis, we identified that 1) age groups that most likely lack of MMR vaccine-induced immunity had the poorest outcome in COVID-19, and 2) COVID-19 disease burden correlates with rubella antibody titres, potentially induced by SARS-CoV2 homologous sequences. We therefore propose that vaccination of at risk age groups with an MMR vaccination merits further consideration as a time-appropriate and safe intervention.

positive: Serology characteristics of SARS-CoV-2 infection since the exposure and post symptoms onset Background Timely diagnosis of SARS-CoV-2 infection is the prerequisite for treatment and preventive quarantine. The serology characteristics and complement diagnosis value of antibody test to RNA test needs to be demonstrated. Method A patient cohort study was conducted at the first affiliated hospital of Zhejiang University, China. Serial sera of COVID-19 patients were collected and total antibody (Ab), IgM and IgG antibody against SARS-CoV-2 were detected. The antibody dynamics during the infection were described. Results The seroconversion rate for Ab, IgM and IgG in COVID-19 patients was 98.8% (79/80), 93.8% (75/80) and 93.8% (75/80), respectively. The first detectible serology marker is total antibody and followed by IgM and IgG, with a median seroconversion time of 15, 18 and 20 day post exposure (d.p.e) or 9, 10 and 12 days post onset, separately. The antibody levels increased rapidly since 6 d.p.o and accompanied with the decline of viral load. For patients in the early stage of illness (0-7d.p.o),Ab showed the highest sensitivity (64.1%) compared to the IgM and IgG (33.3% for both, p<0.001). The sensitivities of Ab, IgM and IgG detection increased to 100%, 96.7% and 93.3% two weeks later, respectively. Conclusions Typical acute antibody response is induced during the SARS-CoV-2 infection. The serology testing provides important complementation to RNA test for pathogenic specific diagnosis and helpful information to evaluate the adapted immunity status of patient. It should be strongly recommended to apply well-validated antibody tests in the clinical management and public health practice to improve the control of COVID-19 infection.

positive: Grundlagen der Replikation und der Immunologie von SARS-CoV-2 Coronaviruses are a genetically highly variable family of viruses that infect vertebrates and have succeeded in infecting humans many times by overcoming the species barrier. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which initially appeared in China at the end of 2019, exhibits a high infectivity and pathogenicity compared to other coronaviruses. As the viral coat and other viral components are recognized as being foreign by the immune system, this can lead to initial symptoms, which are induced by the very efficiently working immune defense system via the respiratory epithelium. During severe courses a systemically expressed proinflammatory cytokine storm and subsequent changes in the coagulation and complement systems can occur. Virus-specific antibodies, the long-term expression of which is ensured by the formation of B memory cell clones, generate a specific immune response that is also detectable in blood (seroconversion). Specifically effective cytotoxic CD8+ T‑cell populations are also formed, which recognize viral epitopes as pathogen-specific patterns in combination with MHC presentation on the cell surface of virus-infected cells and destroy these cells. At the current point in time it is unclear how regular, robust and durable this immune status is constructed. Experiences with other coronavirus infections (SARS and Middle East respiratory syndrome, MERS) indicate that the immunity could persist for several years. Based on animal experiments, already acquired data on other coronavirus types and plausibility assumptions, it can be assumed that seroconverted patients have an immunity of limited duration and only a very low risk of reinfection. Knowledge of the molecular mechanisms of viral cycles and immunity is an important prerequisite for the development of vaccination strategies and development of effective drugs.

positive: Bystander CD4 T cells do not mediate demyelination in mice infected with a neurotropic coronavirus Abstract Demyelination following infection of mice with the neurotropic coronavirus mouse hepatitis virus strain JHM (MHV) is immune-mediated. It has been demonstrated that MHV-specific CD4 and CD8 T cells are capable of causing demyelination independent of the other T cell subset. Recent work has also demonstrated that activated bystander CD8 T cells mediate significant demyelination. The ability of bystander CD4 T cells to mediate demyelination was investigated using CD4 T cell transgenic mice. The results indicated that bystander CD4 T cells were unable to cause demyelination in MHV-infected mice, despite being recruited into the central nervous system (CNS) and irrespective of activation status. These results suggest that CD4 T cells must recognize antigen in the CNS in order to cause demyelination.

positive: Do pets protect their owners in the COVID-19 era?

positive: SARS-CoV-2 and SARS-CoV Spike-RBD Structure and Receptor Binding Comparison and Potential Implications on Neutralizing Antibody and Vaccine Development SARS-CoV-2 and SARS-CoV share a common human receptor ACE2. Protein-protein interaction structure modeling indicates that spike-RBD of the two viruses also has similar overall binding conformation and binding free energy to ACE2. In vitro assays using recombinant ACE2 proteins and ACE2 expressing cells confirmed the two coronaviruses’ similar binding affinities to ACE2. The above studies provide experimental supporting evidences and possible explanation for the high transmissibility observed in the SARS-CoV-2 outbreak. Potent ACE2-blocking SARS-CoV neutralizing antibodies showed limited cross-binding and neutralizing activities to SARS-CoV-2. ACE2-non-blocking SARS-CoV RBD antibodies, though with weaker neutralizing activities against SARS-CoV, showed positive cross-neutralizing activities to SARS-CoV-2 with an unknown mechanism. These findings suggest a trade-off between the efficacy and spectrum for therapeutic antibodies to different coronaviruses, and hence highlight the possibilities and challenges in developing broadly protecting antibodies and vaccines against SARS-CoV-2 and its future mutants.

positive: T-cell-mediated immune response to respiratory coronaviruses Emerging respiratory coronaviruses such as the Severe Acute Respiratory Syndrome coronavirus (SARS-CoV) and Middle East Respiratory Syndrome coronavirus (MERS-CoV) pose potential biological threats to humans. SARS and MERS are manifested as severe atypical pneumonia associated with high morbidity and mortality in humans. The majority of studies carried out in SARS-CoV-infected humans and animals attribute a dysregulated/exuberant innate response as a leading contributor to SARS-CoV-mediated pathology. A decade after the 2002–2003 SARS epidemic, we do not have any approved preventive or therapeutic agents available in case of re-emergence of SARS-CoV or other related viruses. A strong neutralizing antibody response generated against the spike (S) glycoprotein of SARS-CoV is completely protective in the susceptible host. However, neutralizing antibody titers and the memory B cell response are short-lived in SARS-recovered patients and the antibody will target primary homologous strain. Interestingly, the acute phase of SARS in humans is associated with a severe reduction in the number of T cells in the blood. Surprisingly, only a limited number of studies have explored the role of the T cell-mediated adaptive immune response in respiratory coronavirus pathogenesis. In this review, we discuss the role of anti-virus CD4 and CD8 T cells during respiratory coronavirus infections with a special emphasis on emerging coronaviruses.

positive: Neutralising antibodies to SARS coronavirus 2 in Scottish blood donors - a pilot study of the value of serology to determine population exposure Background. The extent of spread of SARS coronavirus 2 (SARS-CoV-2) in the UK and elsewhere is unknown because typically only symptomatic individuals are diagnosed. We performed a serological study of recent blood donors in Scotland to detect antibodies to SARS-CoV-2 as a marker of past infection. Methods. A pseudotyped SARS-CoV-2 virus microneutralisation assay was used to detect neutralising antibodies to SARS-CoV-2. The study group comprised samples from 1000 blood donors collected in Scotland during March, 2020. Controls were collected from 100 donors in Scotland during 2019. Findings. All samples collected on the 17th March, 2020 (n=500) were negative in the pseudotyped SARS-CoV-2 virus microneutralisation assay. Neutralising antibodies were detected in 5 of the 500 samples collected 21st to 23rd March; one further sample was reactive in an anti-spike ELISA. Interpretation. Although we cannot use the rise in numbers seropositive to infer the contemporary seroprevalence or the growth rate of the epidemic, we note that they are consistent with frequency of reported diagnosed infections and SARS-CoV-2-associated deaths reported in that time period in Scotland, given that seroconversion takes up to 2-3 weeks. It should also be noted that blood donors are not representative of the general population; in particular, those with a history of recent respiratory infections are deferred. Finally, it is unknown what proportion of infected individuals seroconvert and become reactive in the assays used. Serial follow up studies are needed to track infection and seroconversion in this and other similar populations However, these data indicate that sero-surveys of blood banks can serve as a useful tool for tracking the emergence and progression of an epidemic like the current SARS-CoV-2 outbreak.

positive: Identification of Human Single-Domain Antibodies against SARS-CoV-2 The worldwide spread of COVID-19 highlights the need for an efficient approach to rapidly develop therapeutics and prophylactics against SARS-CoV-2. The SARS-CoV-2 spike protein, containing the receptor-binding domain (RBD) and S1 subunit involved in receptor engagement, is a potential therapeutic target. We describe the development of a phage-displayed single-domain antibody library by grafting naive complementarity-determining regions (CDRs) into framework regions of a human germline immunoglobulin heavy chain variable region (IGHV) allele. Panning this library against SARS-CoV-2 RBD and S1 subunit identified fully human single-domain antibodies targeting five distinct epitopes on SARS-CoV-2 RBD with subnanomolar to low nanomolar affinities. Some of these antibodies neutralize SARS-CoV-2 by targeting a cryptic epitope located in the spike trimeric interface. Collectively, this work presents a versatile platform for rapid antibody isolation and identifies promising therapeutic anti-SARS-CoV-2 antibodies as well as the diverse immogneic profile of the spike protein.

positive: COVID-19 vaccine design: the Janus face of immune enhancement Previous work on severe acute respiratory syndrome coronavirus (SARS-CoV) vaccines identified cellular immunopathology and antibody-dependent enhancement as potential safety issues. We discuss the implications of these findings for COVID-19 vaccine development and our approach to optimizing for safety and efficacy.

positive: Chimeric severe acute respiratory syndrome coronavirus (SARS-CoV) S glycoprotein and influenza matrix 1 efficiently form virus-like particles (VLPs) that protect mice against challenge with SARS-CoV SARS-CoV was the cause of the global pandemic in 2003 that infected over 8000 people in 8 months. Vaccines against SARS are still not available. We developed a novel method to produce high levels of a recombinant SARS virus-like particles (VLPs) vaccine containing the SARS spike (S) protein and the influenza M1 protein using the baculovirus insect cell expression system. These chimeric SARS VLPs have a similar size and morphology to the wild type SARS-CoV. We tested the immunogenicity and protective efficacy of purified chimeric SARS VLPs and full length SARS S protein vaccines in a mouse lethal challenge model. The SARS VLP vaccine, containing 0.8 μg of SARS S protein, completely protected mice from death when administered intramuscular (IM) or intranasal (IN) routes in the absence of an adjuvant. Likewise, the SARS VLP vaccine, containing 4 μg of S protein without adjuvant, reduced lung virus titer to below detectable level, protected mice from weight loss, and elicited a high level of neutralizing antibodies against SARS-CoV. Sf9 cell-produced full length purified SARS S protein was also an effective vaccine against SARS-CoV but only when co-administered IM with aluminum hydroxide. SARS-CoV VLPs are highly immunogenic and induce neutralizing antibodies and provide protection against lethal challenge. Sf9 cell-based VLP vaccines are a potential tool to provide protection against novel pandemic agents.

positive: Serology of Severe Acute Respiratory Syndrome: Implications for Surveillance and Outcome Background. Severe acute respiratory syndrome (SARS) is a novel infectious disease. No information is currently available on host-specific immunity against the SARS coronavirus (CoV), and detailed characteristics of the epidemiology of SARS CoV infection have not been identified. Methods. ELISA was used to detect antibody to SARS CoV. Reverse-transcriptase polymerase chain reaction was used to detect SARS CoV RNA. T cells in peripheral blood of patients were quantified by flow cytometry. Results. Of 36 patients with probable SARS CoV infection, 30 (83.3%) were positive for IgG antibody to SARS CoV; in contrast, only 3 of 48 patients with suspected SARS CoV infection, 0 of 112 patients with fever but without SARS, and 0 of 96 healthy control individuals were positive for it. IgG antibody to SARS CoV was first detected between day 5 and day 47 after onset of illness (mean ± SD, 18.7±10.4). Conclusion. Detection of antibody to SARS CoV is useful in the diagnosis of SARS; however, at the incubation and initial phases of the illness, serological assay is of little value, because of late seroconversion in most patients.

positive: A serological assay to detect SARS-CoV-2 seroconversion in humans SARS-Cov-2 (severe acute respiratory disease coronavirus 2), which causes Coronavirus Disease 2019 (COVID19) was first detected in China in late 2019 and has since then caused a global pandemic. While molecular assays to directly detect the viral genetic material are available for the diagnosis of acute infection, we currently lack serological assays suitable to specifically detect SARS-CoV-2 antibodies. Here we describe serological enzyme-linked immunosorbent assays (ELISA) that we developed using recombinant antigens derived from the spike protein of SARS-CoV-2. Using negative control samples representing pre-COVID 19 background immunity in the general adult population as well as samples from COVID19 patients, we demonstrate that these assays are sensitive and specific, allowing for screening and identification of COVID19 seroconverters using human plasma/serum as early as two days post COVID19 symptoms onset. Importantly, these assays do not require handling of infectious virus, can be adjusted to detect different antibody types and are amendable to scaling. Such serological assays are of critical importance to determine seroprevalence in a given population, define previous exposure and identify highly reactive human donors for the generation of convalescent serum as therapeutic. Sensitive and specific identification of coronavirus SARS-Cov-2 antibody titers may, in the future, also support screening of health care workers to identify those who are already immune and can be deployed to care for infected patients minimizing the risk of viral spread to colleagues and other patients.

positive: From mice to monkeys, animals studied for coronavirus answers.

positive: Estimating population immunity without serological testing We propose an approximate methodology for estimating the overall level of immunity against COVID-19 in a population that has been affected by the recent epidemic. The methodology relies on the currently available mortality data and utilizes the properties of the SIR model. We illustrate the application of the method by estimating the recent levels of immunity in 10 US states with highest case numbers of COVID-19.

positive: Antibodies to coronaviruses are higher in older compared with younger adults and binding antibodies are more sensitive than neutralizing antibodies in identifying coronavirus‐associated illnesses Human coronaviruses (HCoV) are common causes of respiratory illnesses (RI) despite preexisting humoral immunity. Sera were obtained near the onset of RI and 3 to 4 weeks later as part of a prospective study of 200 subjects evaluated for RI from 2009 to 2013. Antibodies against common HCoV strains were measured by enzyme‐linked immunosorbent assay and neutralization assay comparing older adults with cardiopulmonary diseases (99 subjects) to younger, healthy adults (101 subjects). Virus shedding was detected in respiratory secretions by polymerase chain reaction. Of 43 HCoV‐associated illnesses, 15 (35%) occurred in 14 older adults (aged ≥60 years) and 28 (65%) in 28 younger adults (aged 21‐40 years). Binding and neutralizing antibodies were higher in older adults. Only 16 (35.7%) of RI with increases in binding antibodies also had increases in neutralizing antibodies to HCoV. Increases in binding antibodies with RI were more frequent than increased neutralizing antibodies and virus shedding, and more frequent in younger compared to older adults. Functional neutralizing antibodies were not stimulated as often as binding antibodies, explaining in part a susceptibility to reinfection with HCoV. Monitoring binding antibodies may be more sensitive for the serologic detection of HCoV infections.

positive: COVID-19 immunity passports and vaccination certificates: scientific, equitable, and legal challenges

positive: New IgM seroconversion and positive RT-PCR test after exposure to the virus in recovered COVID-19 patient

positive: Serodiagnostics for Severe Acute Respiratory Syndrome–Related Coronavirus-2: A Narrative Review Accurate serologic tests to detect host antibodies to severe acute respiratory syndrome–related coronavirus-2 (SARS-CoV-2) will be critical for the public health response to the coronavirus disease 2019 pandemic. Many use cases are envisaged, including complementing molecular methods for diagnosis of active disease and estimating immunity for individuals. At the population level, carefully designed seroepidemiologic studies will aid in the characterization of transmission dynamics and refinement of disease burden estimates and will provide insight into the kinetics of humoral immunity. Yet, despite an explosion in the number and availability of serologic assays to test for antibodies against SARS-CoV-2, most have undergone minimal external validation to date. This hinders assay selection and implementation, as well as interpretation of study results. In addition, critical knowledge gaps remain regarding serologic correlates of protection from infection or disease, and the degree to which these assays cross-react with antibodies against related coronaviruses. This article discusses key use cases for SARS-CoV-2 antibody detection tests and their application to serologic studies, reviews currently available assays, highlights key areas of ongoing research, and proposes potential strategies for test implementation.

positive: Longitudinal Change of SARS-Cov2 Antibodies in Patients with COVID-19 BACKGROUND: A novel coronavirus, SARS-CoV-2, has recently emerged and caused the rapid spread of COVID-19 worldwide. METHODS: We did a retrospective study and included COVID-19 patients admitted to Renmin Hospital of Wuhan University between February 1 and February 29, 2020. Antibody assay was conducted to detect COVID-19 envelope protein E and nucleocapsid protein N antigen. RESULTS: 112 patients were recruited with symptoms of fever, cough, fatigue, myalgia, and diarrhoea. All patients underwent antibody tests. Fifty-eight (51.79%) were positive for both IgM and IgG, 7 (6.25%) were negative for both antibodies, 1 (0.89%) was positive for only IgM, and 46 (41.07%) were positive for only IgG. IgM antibody appeared within a week post disease onset, and lasted for one month and gradually decreased, while IgG antibody was produced 10 days after infection, and lasted for a longer time. However, no significant difference in level of IgM and IgG antibody between positive and negative patients of nucleic acid test after treatment was found. CONCLUSIONS: Our results indicate that serological tests could be powerful approach for the early diagnosis of COVID-19.

positive: Virtual screening-driven drug discovery of SARS-CoV2 enzyme inhibitors targeting viral attachment, replication, post-translational modification and host immunity evasion infection mechanisms The novel coronavirus SARS-CoV2, the causative agent of the pandemic disease COVID-19, emerged in December 2019 forcing lockdown of communities in many countries. The absence of specific drugs and vaccines, the rapid transmission of the virus, and the increasing number of deaths worldwide necessitated the discovery of new substances for anti-COVID-19 drug development. With the aid of bioinformatics and computational modelling, ninety seven antiviral secondary metabolites from fungi were docked onto five SARS-CoV2 enzymes involved in viral attachment, replication, post-translational modification, and host immunity evasion infection mechanisms followed by molecular dynamics simulation and in silico ADMET prediction (absorption, distribution, metabolism, excretion and toxicity) of the hit compounds. Thus, three fumiquinazoline alkaloids scedapin C (15), quinadoline B (19) and norquinadoline A (20), the polyketide isochaetochromin D1 (8), and the terpenoid 11a-dehydroxyisoterreulactone A (11) exhibited high binding affinities on the target proteins, papain-like protease (PLpro), chymotrypsin-like protease (3CLpro), RNA-directed RNA polymerase (RdRp), non-structural protein 15 (nsp15), and the spike binding domain to GRP78. Molecular dynamics simulation was performed to optimize the interaction and investigate the stability of the top-scoring ligands in complex with the five target proteins. All tested complexes were found to have dynamic stability. Of the five top-scoring metabolites, quinadoline B (19) was predicted to confer favorable ADMET values, high gastrointestinal absorptive probability and poor blood-brain barrier crossing capacities.Communicated by Ramaswamy H. Sarma.

positive: Immune responses in COVID-19 and potential vaccines: Lessons learned from SARS and MERS epidemic As the world is witnessing the epidemic of COVID-19, a disease caused by a novel coronavirus, SARS-CoV-2, emerging genetics and clinical evidences suggest a similar path to those of SARS and MERS. The rapid genomic sequencing and open access data, together with advanced vaccine technology, are expected to give us more knowledge on the pathogen itself, including the host immune response as well as the plan for therapeutic vaccines in the near future. This review aims to provide a comparative view among SARS-CoV, MERS-CoV and the newly epidemic SARS-CoV-2, in the hope to gain a better understanding of the host-pathogen interaction, host immune responses, and the pathogen immune evasion strategies. This predictive view may help in designing an immune intervention or preventive vaccine for COVID-19 in the near future.

positive: What policy makers need to know about COVID-19 protective immunity

positive: Development of passive immunity against SARS-CoV-2 for management of immunodeficient patients-a perspective

positive: Respiratory virus-induced heterologous immunity: Part of the problem or part of the solution? PURPOSE: To provide current knowledge on respiratory virus-induced heterologous immunity (HI) with a focus on humoral and cellular cross-reactivity. Adaptive heterologous immune responses have broad implications on infection, autoimmunity, allergy and transplant immunology. A better understanding of the mechanisms involved might ultimately open up possibilities for disease prevention, for example by vaccination. METHODS: A structured literature search was performed using Medline and PubMed to provide an overview of the current knowledge on respiratory-virus induced adaptive HI. RESULTS: In HI the immune response towards one antigen results in an alteration of the immune response towards a second antigen. We provide an overview of respiratory virus-induced HI, including viruses such as respiratory syncytial virus (RSV), rhinovirus (RV), coronavirus (CoV) and influenza virus (IV). We discuss T cell receptor (TCR) and humoral cross-reactivity as mechanisms of HI involving those respiratory viruses. Topics covered include HI between respiratory viruses as well as between respiratory viruses and other pathogens. Newly developed vaccines, which have the potential to provide protection against multiple virus strains are also discussed. Furthermore, respiratory viruses have been implicated in the development of autoimmune diseases, such as narcolepsy, Guillain-Barré syndrome, type 1 diabetes or myocarditis. Finally, we discuss the role of respiratory viruses in asthma and the hygiene hypothesis, and review our recent findings on HI between IV and allergens, which leads to protection from experimental asthma. CONCLUSION: Respiratory-virus induced HI may have protective but also detrimental effects on the host. Respiratory viral infections contribute to asthma or autoimmune disease development, but on the other hand, a lack of microbial encounter is associated with an increasing number of allergic as well as autoimmune diseases. Future research might help identify the elements which determine a protective or detrimental outcome in HI-based mechanisms.

positive: COVID-19 and the immune system A close interaction between the virus SARS-CoV-2 and the immune system of an individual results in a diverse clinical manifestation of the COVID-19 disease While adaptive immune responses are essential for SARS-CoV-2 virus clearance, the innate immune cells, such as macrophages, may contribute, in some cases, to the disease progression Macrophages have shown a significant production of IL-6 suggesting they may contribute to the excessive inflammation in COVID-19 disease Macrophage Activation Syndrome may further explain the high serum levels of CRP, which are normally lacking in viral infections In adaptive immune responses, it has been revealed that cytotoxic CD8+ T cells exhibit functional exhaustion patterns, such as the expression of NKG2A, PD-1, and TIM-3 Since SARS-CoV-2 restrains antigen presentation by downregulating MHC class I and II molecules and, therefore, inhibits the T cell-mediated immune responses, humoral immune responses also play a substantial role Specific IgA response appears to be stronger and more persistent than IgM response Moreover, IgM and IgG antibodies show similar dynamics in COVID-19 disease

positive: Long-term and herd immunity against SARS-CoV-2: implications from current and past knowledge Effective herd immunity against SARS-CoV-2 will be determined on many factors: the percentage of the immune population, the length and effectiveness of the immune response and the stability of the viral epitopes. The required percentage of immune individuals has been estimated to be 50-66% of the population which, given the current infection rates, will take long to be achieved. Furthermore, data from SARS-CoV suggest that the duration of immunity may not be sufficiently significant, while the immunity response against SARS-CoV-2 may not be efficiently effective in all patients, as relapses have already been reported. In addition, the development of mutant strains, which has already been documented, can cause the reemergence of the epidemic. In conclusion, the development of an effective vaccine is an urgent necessity, as long-term natural immunity to SARS-CoV-2 may not be sufficient for the control of the current and future outbreaks.

positive: Multiplex detection and dynamics of IgG antibodies to SARS-CoV2 and the highly pathogenic human coronaviruses SARS-CoV and MERS-CoV BACKGROUND: Knowledge of the COVID-19 epidemic extent and the level of herd immunity is urgently needed to help manage this pandemic. METHODS: We used a panel of 167 samples (77 pre-epidemic and 90 COVID-19 seroconverters) and SARS-CoV1, SARS-CoV2 and MERS-CoV Spike and/or Nucleopcapsid (NC) proteins to develop a high throughput multiplex screening assay to detect IgG antibodies in human plasma. Assay performances were determined by ROC curves analysis. A subset of the COVID-19+ samples (n = 36) were also tested by a commercial NC-based ELISA test and the results compared with those of the novel assay. RESULTS: On samples collected ≥14 days after symptoms onset, the accuracy of the assay is 100 % (95 % CI: 100-100) for the Spike antigen and 99.9 % (95 % CI:99.7-100) for NC. By logistic regression, we estimated that 50 % of the patients have seroconverted at 5.7 ± 1.6; 5.7 ± 1.8 and 7.9 ± 1.0 days after symptoms onset against Spike, NC or both antigens, respectively and all have seroconverted two weeks after symptoms onset. IgG titration in a subset of samples showed that early phase samples present lower IgG titers than those from later phase. IgG to SARS-CoV2 NC cross-reacted at 100 % with SARS-CoV1 NC. Twenty-nine of the 36 (80.5 %) samples tested were positive by the commercial ELISA while 31/36 (86.1 %) were positive by the novel assay. CONCLUSIONS: Our assay is highly sensitive and specific for the detection of IgG antibodies to SARS-CoV2 proteins, suitable for high throughput epidemiological surveys. The novel assay is more sensitive than a commercial ELISA.

positive: Immunization with SARS-CoV S DNA vaccine generates memory CD4(+) and CD8(+) T cell immune responses An effective vaccine for severe acute respiratory syndrome (SARS) will probably require the generation and maintenance of both humoral and cellular immune responses. It has been reported that after natural infection in humans and immunization in animals with SARS-CoV vaccine, antibody is produced and persistent for a long period of time. In the present study, mice were immunized i.m. with SARS-CoV S DNA vaccine, and three different methods (ELISA, ELISPOT and FACS) were used to evaluate the immune responses when the cells were stimulated in vitro with a pool of peptides overlapping entire SARS spike protein. The results show that prime-immunization with SARS-CoV S DNA vaccine can induce both CD4(+) and CD8(+) T cell responses. Boosting with the same vaccine enhances CD4(+) and CD8(+) T cell responses in both lymphoid and nonlymphoid organs and were persistent over two months. The SARS-CoV S-specific CD4(+) and CD8(+) T cells were CD62L(−), a marker for memory cells, and −30 to 50% of the cells expressed IL-7Rα (CD127), a marker for the capacity of effector cells to develop into memory cells. In addition, immunization with the DNA vaccine elicited high levels of antibody production. Taken together, these data demonstrate that immunization with SARS-CoV S DNA vaccine can generate antigen-specific humoral and cellular immune responses that may contribute to long-term protection.

positive: Increased expression of CD8 marker on T-cells in COVID-19 patients Abstract Background Cell-mediated immunity including T-cells (T helper and cytotoxic) plays an essential role in efficient antiviral responses against coronavirus disease-2019 (COVID-19). Therefore, in this study, we evaluated the ratio and expression of CD4 and CD8 markers in COVID-19 patients to clarify the immune characterizations of CD4 and CD8 T-cells in COVID-19 patients. Methods Peripheral blood samples of 25 COVID-19 patients and 25 normal individuals with similar age and sex as the control group were collected. White blood cells, platelets, and lymphocytes were counted and CD4 and CD8 T lymphocytes were evaluated by flow cytometry. Results The number of white blood cells, lymphocytes, and platelets were reduced significantly in COVID-19 patients (P < 0.05). The difference in CD4:CD8 ratio, CD4 T-cell frequency, CD8 T-cell frequency, and CD4 mean fluorescence intensity (MFI) was not significant between COVID-19 patients and healthy individuals (P > 0.05); however, the CD8 MFI increased significantly in COVID-19 infected patients (P < 0.05). Conclusion Although, there is no significant difference in the ratio of CD4 to CD8 between two groups, the expression level of CD8 in COVID-19 patients was significantly higher than the normal individuals. This result suggested that the cellular immune responses triggered by COVID-19 infection were developed through overexpression of CD8 and hyperactivation of cytotoxic T lymphocytes.

positive: A highly conserved cryptic epitope in the receptor-binding domains of SARS-CoV-2 and SARS-CoV The outbreak of COVID-19 caused by SARS-CoV-2 virus has now become a pandemic, but there is currently very little understanding of the antigenicity of the virus. We therefore determined the crystal structure of CR3022, a neutralizing antibody previously isolated from a convalescent SARS patient, in complex with the receptor-binding domain (RBD) of the SARS-CoV-2 spike (S) protein to 3.1 Å. CR3022 targets a highly conserved epitope, distal from the receptor-binding site, that enables cross-reactive binding between SARS-CoV-2 and SARS-CoV. Structural modeling further demonstrates that the binding epitope can only be accessed by CR3022 when at least two RBD on the trimeric S protein are in the “up” conformation and slightly rotated. Overall, this study provides molecular insights into antibody recognition of SARS-CoV-2.

positive: Antibody-mediated synergy and interference in the neutralization of SARS-CoV at an epitope cluster on the spike protein Abstract Incomplete neutralization of virus, especially when it occurs in the presence of excess neutralizing antibody, represents a biological phenomenon that impacts greatly on antibody-mediated immune prophylaxis of viral infection and on successful vaccine design. To understand the mechanism by which a virus escapes from antibody-mediated neutralization, we have investigated the interactions of non-neutralizing and neutralizing antibodies at an epitope cluster on the spike protein of severe acute respiratory syndrome coronavirus (SARS-CoV). The epitope cluster was mapped at the C-terminus of the spike protein; it consists of structurally intertwined epitopes recognized by two neutralizing monoclonal antibodies (mAbs), 341C and 540C, and a non-neutralizing mAb, 240C. While mAb 341C binds to a mostly linear epitope composed of residues 507PAT509 and V349, mAb 240C binds to an epitope that partially overlaps the former by at least two residues (P507 and A508). The epitope corresponding to mAb 540C is a conformational one, involving residues L504 and N505. In neutralization assays, non-neutralizing 240C disrupted virus neutralization by mAb 341C and/or mAb 540C, whereas a combination of mAbs 341C and 540C blocked virus infectivity synergistically. These findings indicate that the epitope cluster on the spike protein may serve as an evolutionarily conserved platform at which a dynamic interplay between neutralizing and non-neutralizing antibodies occurs, thereby determining the outcome of SARS-CoV infection.

positive: Animal models for emerging coronavirus: progress and new insights The emergences of coronaviruses have caused a serious global public health problem because their infection in humans caused the severe acute respiratory disease and deaths. The outbreaks of lethal coronaviruses have taken place for three times within recent two decades (SARS-CoV in 2002, MERS-CoV in 2012 and SARS-CoV-2 in 2019). Much more serious than SARS-CoV in 2002, the current SARS-CoV-2 infection has been spreading to more than 213 countries, areas or territories and causing more than two million cases up to date (17 April 2020). Unfortunately, no vaccine and specific anti-coronavirus drugs are available at present time. Current clinical treatment at hand is inadequate to suppress viral replication and inflammation, and reverse organ failure. Intensive research efforts have focused on increasing our understanding of viral biology of SARS-CoV-2, improving antiviral therapy and vaccination strategies. The animal models are important for both the fundamental research and drug discovery of coronavirus. This review aims to summarize the animal models currently available for SARS-CoV and MERS-CoV, and their potential use for the study of SARS-CoV-2. We will discuss the benefits and caveats of these animal models and present critical findings that might guide the fundamental studies and urgent treatment of SARS-CoV-2-caused diseases.

positive: COVID-19 Related Mortality: Is the BCG Vaccine Truly Effective? The coronavirus disease 2019 (COVID-19) pandemic has become a worldwide emergency. In the attempt to search for interventions that would improve outcomes, some studies have looked at the potential benefit of BCG vaccination. These past studies have found a statistically significant reduction in COVID-19 related mortality in countries with a current universal bacille Calmette-Guerin (BCG) vaccination policy. However, just as the authors themselves noted, the nature of ecological studies make them very prone to the presence of several confounders. This paper took into account demographic differences, economic differences and the different stages of the pandemic in each country; gathering data from publicly available sources. It was found that no statistically significant difference exists in mortality rates between countries with a current or prior BCG vaccination policy when compared to those that never had such a program. Nevertheless, the immunostimulatory potential of the BCG vaccine might still prove useful in the development of future vaccines or other prophylactic measures.

positive: HLA studies in the context of coronavirus outbreaks.

positive: Global epidemiology, pathogenesis, immune response, diagnosis, treatment, economic and psychological impact, challenges, and future prevention of COVID-19: A scoping review Background: Globally, the novel coronavirus, is a public health problem causing respiratory infections. Since the outbreak of severe acute and Middle East respiratory syndromes coronavirus was not reported to cause human infections. Now, it become an epidemic proportion with growing number of cases and deaths. Methods: A scoping review was conducted following the methodological framework. In this scoping review, 50 records published before 28 March, 2020 were included and discussed to better understand the current epidemiology, pathogenesis, immunological response, diagnosis, evasion mechanisms and suggested strategies to boost the immune system, challenges, treatment, and future preventions of the virus. PubMed, BioRxiv, MedRxiv, Global Health and google scholars were searched comprehensively for articles, preprints, grey literatures, reports, websites, conference proceedings and expert information. Studies conducted in human and published in the English language were included in the analysis. All the findings and statements of the review regarding the outbreak are based on published information as listed in citations. Results: We identified 360 records, of which 50 studies met the inclusion criteria. We synthesized the data from the included records and dig out the deep insights of them and pooled into this review. The burden of the outbreak is worsening due to overcrowding, presence of asymptomatic carriers, scarcity of test kits, the immune escaping ability of the virus and lack of awareness. Conclusions and recommendations: Due to the fast-spreading nature of COVID-19 the prevention and control strategies become challenging. It is imposing social, psychological, and socio-economic impacts. We recommended that following social distancing, isolation suspects, using personal protective equipment, health education and introducing handwashing practices, avoiding contact with animals, vaccine development and treatment for controlling and prevention.

positive: Coronavirus membrane-associated papain-like proteases induce autophagy through interacting with Beclin1 to negatively regulate antiviral innate immunity Autophagy plays important roles in modulating viral replication and antiviral immune response. Coronavirus infection is associated with the autophagic process, however, little is known about the mechanisms of autophagy induction and its contribution to coronavirus regulation of host innate responses. Here, we show that the membrane-associated papain-like protease PLP2 (PLP2-TM) of coronaviruses acts as a novel autophagy-inducing protein. Intriguingly, PLP2-TM induces incomplete autophagy process by increasing the accumulation of autophagosomes but blocking the fusion of autophagosomes with lysosomes. Furthermore, PLP2-TM interacts with the key autophagy regulators, LC3 and Beclin1, and promotes Beclin1 interaction with STING, the key regulator for antiviral IFN signaling. Finally, knockdown of Beclin1 partially reverses PLP2-TM’s inhibitory effect on innate immunity which resulting in decreased coronavirus replication. These results suggested that coronavirus papain-like protease induces incomplete autophagy by interacting with Beclin1, which in turn modulates coronavirus replication and antiviral innate immunity.

positive: A subcutaneously injected UV-inactivated SARS coronavirus vaccine elicits systemic humoral immunity in mice The recent emergence of severe acute respiratory syndrome (SARS) was caused by a novel coronavirus, SARS-CoV. It spread rapidly to many countries and developing a SARS vaccine is now urgently required. In order to study the immunogenicity of UV-inactivated purified SARS-CoV virion as a vaccine candidate, we subcutaneously immunized mice with UV-inactivated SARS-CoV with or without an adjuvant. We chose aluminum hydroxide gel (alum) as an adjuvant, because of its long safety history for human use. We observed that the UV-inactivated SARS-CoV virion elicited a high level of humoral immunity, resulting in the generation of long-term antibody secreting and memory B cells. With the addition of alum to the vaccine formula, serum IgG production was augmented and reached a level similar to that found in hyper-immunized mice, though it was still insufficient to elicit serum IgA antibodies. Notably, the SARS-CoV virion itself was able to induce long-term antibody production even without an adjuvant. Anti-SARS-CoV antibodies elicited in mice recognized both the spike and nucleocapsid proteins of the virus and were able to neutralize the virus. Furthermore, the UV-inactivated virion induced regional lymph node T-cell proliferation and significant levels of cytokine production (IL-2, IL-4, IL-5, IFN-γ and TNF-α) upon restimulation with inactivated SARS-CoV virion in vitro. Thus, a whole killed virion could serve as a candidate antigen for a SARS vaccine to elicit both humoral and cellular immunity.

positive: Serological responses in patients with severe acute respiratory syndrome coronavirus infection and cross-reactivity with human coronaviruses 229E, OC43, and NL63. The serological response profile of severe acute respiratory syndrome (SARS) coronavirus (CoV) infection was defined by neutralization tests and subclass-specific immunofluorescent (IF) tests using serial sera from 20 patients. SARS CoV total immunoglobulin (Ig) (IgG, IgA, and IgM [IgGAM]) was the first antibody to be detectable. There was no difference in time to seroconversion between the patients who survived (n = 14) and those who died (n = 6). Although SARS CoV IgM was still detectable by IF tests with 8 of 11 patients at 7 months postinfection, the geometric mean titers dropped from 282 at 1 month postinfection to 19 at 7 months (P = 0.001). In contrast, neutralizing antibody and SARS CoV IgGAM and IgG antibody titers remained stable over this period. The SARS CoV antibody response was sometimes associated with an increase in preexisting IF IgG antibody titers for human coronaviruses OC43, 229E, and NL63. There was no change in IF IgG titer for virus capsid antigen from the herpesvirus that was used as an unrelated control, Epstein-Barr virus. In contrast, patients who had OC43 infections, and probably also 229E infections, without prior exposure to SARS CoV had increases of antibodies specific for the infecting virus but not for SARS CoV. There is a need for awareness of cross-reactive antibody responses between coronaviruses when interpreting IF serology.

positive: Immunoglobulin fragment F(ab’)2 against RBD potently neutralizes SARS-CoV-2 in vitro COVID-19 caused by the emerging human coronavirus, SARS-CoV-2, has become a global pandemic, leading a serious threat to human health. So far, there is none vaccines or specific antiviral drugs approved for that. Therapeutic antibodies for SARS-CoV-2, was obtained from hyper immune equine plasma in this study. Herein, SARS-CoV-2 RBD with gram level were obtained through Chinese hamster ovary cells high-density fermentation. The binding of RBD to SARS-CoV-2 receptor, human ACE2, was verified and the efficacy of RBD in vivo was tested on mice and then on horses. As a result, RBD triggered high-titer neutralizing antibodies in vivo, and immunoglobulin fragment F(ab’)2 was prepared from horse antisera through removing Fc. Neutralization test demonstrated that RBD-specific F(ab’)2 inhibited SARS-CoV-2 with EC50 at 0.07 μg/ml, showing a potent inhibitory effect on SARS-CoV-2. These results highlights as RBD-specific F(ab’)2 as therapeutic candidate for SARS-CoV-2.

positive: Natural mutations in the receptor binding domain of spike glycoprotein determine the reactivity of cross-neutralization between palm civet coronavirus and severe acute respiratory syndrome coronavirus. The severe acute respiratory syndrome (SARS) outbreak of 2002 and 2003 occurred as a result of zoonotic transmission. Coronavirus (CoV) found in naturally infected palm civet (civet-CoV) represents the closest genetic relative to SARS-CoV, but the degree and the determinants of cross-neutralization among these viruses remain to be investigated. Studies indicate that the receptor binding domain (RBD) of the SARS-CoV spike (S) glycoprotein contains major determinants for viral entry and neutralization. We aim to characterize the impact of natural mutations within the RBDs of civet-CoVs on viral entry and cross-neutralization. In this study, the S glycoprotein genes were recovered from naturally infected civets in central China (Hubei province), extending the geographic distribution of civet-CoV beyond the southeastern province of Guangdong. Moreover, pseudoviruses generated in our laboratory with four civet S genes, each with a distinct RBD, infected cells expressing human receptor angiotensin-converting enzyme 2, but with 90 to 95% less efficiency compared to that of SARS-CoV. These four civet S genes were also constructed as DNA vaccines to immunize mice. Immunized sera elicited against most civet S glycoproteins displayed potent neutralizing activities against autologous viruses but were much less efficient (50% inhibitory concentration, 20- to 40-fold) at neutralizing SARS-CoV and vice versa. Convalescence-phase sera from humans were similarly ineffective against the dominant civet pseudovirus. Our findings suggest that the design of SARS vaccine should consider not only preventing the reemergence of SARS-CoV but also providing cross-protection, thus interrupting zoonotic transmission of a group of genetically divergent civet CoVs of broad geographic origin.

positive: Virus strain specificity of challenge immunity to coronavirus The resistance of immunized mice to challenge with the same or a different strain of mouse hepatitis virus (MHV) was examined as a model of challenge immunity to coronavirus infection. Genetically susceptible BALB/cByJ mice were given an intranasal immunizing infection of respiratory-type MHV-JHM, MHV-S, or enterotropic MHV-Y. Control mice were sham-immunized with sterile tissue culture fluid. Recovered mice were challenged intranasally with MHV-JHM, MHV-S or sterile tissue culture fluid at 30 days after immunization. Resistance to challenge inoculation was evaluated in groups of mice at 4 and 30 days after challenge. At 4 days, the prevalence of MHV lesions in nose and liver was tabulated and MHV titers in liver were determined. At 30 days, the prevalence of residual brainstem spongiform lesions was tabulated and serum antibody to MHV-JHM and MVH-S was quantified by enzyme immunoassay. Mice immunized with MHV-JHM or MHV-S resisted challenge with the MHV homotype, but MHV-S-immunized mice were fully susceptible to challenge with MVH-JHM. Mice immunized with enterotropic MHV-Y were only partially protected against challenge with antigenically related, but biologically different MHV-S. Serum antibody responses to MHV supported these observations. These data indicate that challenge immunity to coronaviruses is strong, but highly virus strain-specific.

positive: Particulate multivalent presentation of the receptor binding domain induces protective immune responses against MERS-CoV. Middle East respiratory syndrome coronavirus (MERS-CoV) is a WHO priority pathogen for which vaccines are urgently needed. Using an immune-focusing approach, we created self-assembling particles multivalently displaying critical regions of the MERS-CoV spike protein ─fusion peptide, heptad repeat 2, and receptor binding domain (RBD) ─ and tested their immunogenicity and protective capacity in rabbits. Using a "plug-and-display" SpyTag/SpyCatcher system, we coupled RBD to lumazine synthase (LS) particles producing multimeric RBD-presenting particles (RBD-LS). RBD-LS vaccination induced antibody responses of high magnitude and quality (avidity, MERS-CoV neutralizing capacity, and mucosal immunity) with cross-clade neutralization. The antibody responses were associated with blocking viral replication and upper and lower respiratory tract protection against MERS-CoV infection in rabbits. This arrayed multivalent presentation of the viral RBD using the antigen-SpyTag/LS-SpyCatcher is a promising MERS-CoV vaccine candidate and this platform may be applied for the rapid development of vaccines against other emerging viruses such as SARS-CoV-2.

positive: Coronaviruses pandemics: Can neutralizing antibodies help? For the first time in Homo sapiens history, possibly, most of human activities is stopped by coronavirus disease 2019 (COVID-19). Nearly eight billion people of this world are facing a great challenge, maybe not “to be or not to be” yet, but unpredictable. What happens to other major pandemics in the past, and how human beings went through these hurdles? The human body is equipped with the immune system that can recognize, respond and fight against pathogens such as viruses. Following the innate response, immune system processes the adaptive response by which each pathogen is encoded and recorded in memory system. The humoral reaction containing cytokines and antibodies is expected to activate when the pathogens come back. Exploiting this nature of body protection, neutralizing antibodies have been investigated. Learning from past, in parallel to SARS-CoV-2, other coronaviruses SARS-CoV and MERS-CoV who caused previous pandemics, are recalled in this review. We here propose insights of origin and characteristics and perspective for the future of antibodies development.

positive: Anatomical features of anti-viral immunity in the respiratory tract Abstract The mucosal surfaces of the lungs are a major portal of entry for virus infections and there are urgent needs for new vaccines that promote effective pulmonary immunity. However, we have only a rudimentary understanding of the requirements for effective cellular immunity in the respiratory tract. Recent studies have revealed that specialized cellular immune responses and lymphoid tissues are involved in the protection of distinct anatomical microenvironments of the respiratory tract, such as the large airways of the nose and the alveolar airspaces. This review discusses some of the anatomical features of anti-viral immunity in the respiratory tract including the role of local lymphoid tissues and the relationship between effector and memory T cells in the airways, the lung parenchyma, and lymphoid organs.

positive: Immunogenicity of the spike glycoprotein of Bat SARS-like coronavirus A group of SARS-like coronaviruses (SL-CoV) have been identified in horseshoe bats. Despite SL-CoVs and SARS-CoV share identical genome structure and high-level sequence similarity, SL-CoV does not bind to the same cellular receptor as for SARS-CoV and the N-terminus of the S proteins only share 64% amino acid identity, suggesting there are fundamental differences between these two groups of coronaviruses. To gain insight into the basis of this difference, we established a recombinant adenovirus system expressing the S protein from SL-CoV (rAd-Rp3-S) to investigate its immune characterization. Our results showed that immunized mice generated strong humoral immune responses against the SL-CoV S protein. Moreover, a strong cellular immune response demonstrated by elevated IFN-γ and IL-6 levels was also observed in these mice. However, the induced antibody from these mice had weaker cross-reaction with the SARS-CoV S protein, and did not neutralize HIV pseudotyped with SARS-CoV S protein. These results demonstrated that the immunogenicity of the SL-CoV S protein is distinct from that of SARS-CoV, which may cause the immunological differences between human SARS-CoV and bat SL-CoV. Furthermore, the recombinant virus could serve as a potential vaccine candidate against bat SL-CoV infection.

positive: Functional prediction and comparative population analysis of variants in genes for proteases and innate immunity related to SARS-CoV-2 infection New coronavirus SARS-CoV-2 is capable to infect humans and cause a novel disease COVID-19. Aiming to understand a host genetic component of COVID-19, we focused on variants in genes encoding proteases and genes involved in innate immunity that could be important for susceptibility and resistance to SARS-CoV-2 infection. Analysis of sequence data of coding regions of FURIN, PLG, PRSS1, TMPRSS11a, MBL2 and OAS1 genes in 143 unrelated individuals from Serbian population identified 22 variants with potential functional effect. In silico analyses (PolyPhen-2, SIFT, MutPred2 and Swiss-Pdb Viewer) predicted that 10 variants could impact the structure and/or function of proteins. These protein-altering variants (p.Gly146Ser in FURIN; p.Arg261His and p.Ala494Val in PLG; p.Asn54Lys in PRSS1; p.Arg52Cys, p.Gly54Asp and p.Gly57Glu in MBL2; p.Arg47Gln, p.Ile99Val and p.Arg130His in OAS1) may have predictive value for inter-individual differences in the response to the SARS-CoV-2 infection. Next, we performed comparative population analysis for the same variants using extracted data from the 1000 genomes project. Population genetic variability was assessed using delta MAF and Fst statistics. Our study pointed to 7 variants in PLG, TMPRSS11a, MBL2 and OAS1 genes with noticeable divergence in allelic frequencies between populations worldwide. Three of them, all in MBL2 gene, were predicted to be damaging, making them the most promising population-specific markers related to SARS-CoV-2 infection. Comparing allelic frequencies between Serbian and other populations, we found that the highest level of genetic divergence related to selected loci was observed with African, followed by East Asian, Central and South American and South Asian populations. When compared with European populations, the highest divergence was observed with Italian population. In conclusion, we identified 4 variants in genes encoding proteases (FURIN, PLG and PRSS1) and 6 in genes involved in the innate immunity (MBL2 and OAS1) that might be relevant for the host response to SARS-CoV-2 infection.

positive: Broad and strong memory CD4+ and CD8+ T cells induced by SARS-CoV-2 in UK convalescent COVID-19 patients COVID-19 is an ongoing global crisis in which the development of effective vaccines and therapeutics will depend critically on understanding the natural immunity to the virus, including the role of SARS-CoV-2-specific T cells. We have conducted a study of 42 patients following recovery from COVID-19, including 28 mild and 14 severe cases, comparing their T cell responses to those of 16 control donors. We assessed the immune memory of T cell responses using IFNγ based assays with overlapping peptides spanning SARS-CoV-2 apart from ORF1. We found the breadth, magnitude and frequency of memory T cell responses from COVID-19 were significantly higher in severe compared to mild COVID-19 cases, and this effect was most marked in response to spike, membrane, and ORF3a proteins. Total and spike-specific T cell responses correlated with the anti-Spike, anti-Receptor Binding Domain (RBD) as well as anti-Nucleoprotein (NP) endpoint antibody titre (p<0.001, <0.001 and =0.002). We identified 39 separate peptides containing CD4+ and/or CD8+ epitopes, which strikingly included six immunodominant epitope clusters targeted by T cells in many donors, including 3 clusters in spike (recognised by 29%, 24%, 18% donors), two in the membrane protein (M, 32%, 47%) and one in the nucleoprotein (Np, 35%). CD8+ responses were further defined for their HLA restriction, including B*4001-restricted T cells showing central memory and effector memory phenotype. In mild cases, higher frequencies of multi-cytokine producing M- and NP-specific CD8+ T cells than spike-specific CD8+ T cells were observed. They furthermore showed a higher ratio of SARS-CoV-2-specific CD8+ to CD4+ T cell responses. Immunodominant epitope clusters and peptides containing T cell epitopes identified in this study will provide critical tools to study the role of virus-specific T cells in control and resolution of SARS-CoV-2 infections. The identification of T cell specificity and functionality associated with milder disease, highlights the potential importance of including non-spike proteins within future COVID-19 vaccine design.

positive: COVID-19 serology at population scale: SARS-CoV-2-specific antibody responses in saliva Non-invasive SARS-CoV-2 antibody testing is urgently needed to estimate the incidence and prevalence of SARS-CoV-2 infection at the general population level. Precise knowledge of population immunity could allow government bodies to make informed decisions about how and when to relax stay-at-home directives and to reopen the economy. We hypothesized that salivary antibodies to SARS-CoV-2 could serve as a non-invasive alternative to serological testing for widespread monitoring of SARS-CoV-2 infection throughout the population. We developed a multiplex SARS-CoV-2 antibody immunoassay based on Luminex technology and tested 167 saliva and 324 serum samples, including 134 and 118 negative saliva and serum samples, respectively, collected before the COVID-19 pandemic, and 33 saliva and 206 serum samples from participants with RT-PCR-confirmed SARS-CoV-2 infection. We evaluated the correlation of results obtained in saliva vs. serum and determined the sensitivity and specificity for each diagnostic media, stratified by antibody isotype, for detection of SARS-CoV-2 infection based on COVID-19 case designation for all specimens. Matched serum and saliva SARS-CoV-2 antigen-specific IgG responses were significantly correlated. Within the 10-plex SARS-CoV-2 panel, the salivary anti-nucleocapsid (N) protein IgG response resulted in the highest sensitivity for detecting prior SARS-CoV-2 infection (100% sensitivity at ≥10 days post-SARS-CoV-2 symptom onset). The salivary anti-receptor binding domain (RBD) IgG response resulted in 100% specificity. Among individuals with SARS-CoV-2 infection confirmed with RT-PCR, the temporal kinetics of IgG, IgA, and IgM in saliva were consistent with those observed in serum. SARS-CoV-2 appears to trigger a humoral immune response resulting in the almost simultaneous rise of IgG, IgM and IgA levels both in serum and in saliva, mirroring responses consistent with the stimulation of existing, cross-reactive B cells. SARS-CoV-2 antibody testing in saliva can play a critically important role in large-scale “sero”-surveillance to address key public health priorities and guide policy and decision-making for COVID-19.

positive: COVID‐19: a brief history and treatments in development Coronavirus disease (COVID‐19) is now dominating the lives of everyone, and its history is constantly being rewritten. This article gives a brief account of the story so far: where SARS‐CoV‐2 might have originated, how it compares with other viruses that cause major respiratory disease, and some of the treatments and vaccines currently being investigated to combat it.

positive: SARS-CoV-2 assays to detect functional antibody responses that block ACE2 recognition in vaccinated animals and infected patients SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2) has caused a global pandemic of COVID-19 resulting in cases of mild to severe respiratory distress and significant mortality. The global outbreak of this novel coronavirus has now infected >8 million people worldwide with >2 million cases in the US (June 17th, 2020). There is an urgent need for vaccines and therapeutics to combat the spread of this coronavirus. Similarly, the development of diagnostic and research tools to determine infection and vaccine efficacy are critically needed. Molecular assays have been developed to determine viral genetic material present in patients. Serological assays have been developed to determine humoral responses to the spike protein or receptor binding domain (RBD). Detection of functional antibodies can be accomplished through neutralization of live SARS-CoV2 virus, but requires significant expertise, an infectible stable cell line, a specialized BioSafety Level 3 (BSL-3) facility. As large numbers of people return from quarantine, it is critical to have rapid diagnostics that can be widely adopted and employed to assess functional antibody levels in the returning workforce. This type of surrogate neutralization diagnostic can also be used to assess humoral immune responses induced in patients from the large number of vaccine and immunotherapy trials currently on-going. Here we describe a rapid serological diagnostic assay for determining antibody receptor blocking and demonstrate the broad utility of the assay by measuring the antibody functionality of sera from small animals and non-human primates immunized with an experimental SARS-CoV-2 vaccine and using sera from infected patients.

positive: A SARS-CoV-2 Vaccination Strategy Focused on Population-Scale Immunity Here we propose a vaccination strategy for SARS-CoV-2 based on identification of both highly conserved regions of the virus and newly acquired adaptations that are presented by MHC class I and II across the vast majority of the population, are highly dissimilar from the human proteome, and are predicted B cell epitopes. We present 65 peptide sequences that we expect to result in a safe and effective vaccine which can be rapidly tested in DNA, mRNA, or synthetic peptide constructs. These include epitopes that are contained within evolutionarily divergent regions of the spike protein reported to increase infectivity through increased binding to the ACE2 receptor, and within a novel furin cleavage site thought to increase membrane fusion. This vaccination strategy specifically targets unique vulnerabilities of SARS-CoV-2 and should engage a robust adaptive immune response in the vast majority of the human population.

positive: Vaccines for SARS-CoV-2: Lessons from Other Coronavirus Strains. The emergence of the strain of coronavirus SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) and its impact on global health have made imperative the development of effective and safe vaccines for this lethal strain. SARS-CoV-2 now adds to the list of coronavirus diseases that have threatened global health, along with the SARS (severe acute respiratory syndrome) and MERS (Middle East respiratory syndrome) coronaviruses that emerged in 2002/2003 and 2012, respectively. As of April 2020, no vaccine is commercially available for these coronavirus strains. Nevertheless, the knowledge obtained from the vaccine development efforts for MERS and SARS can be of high value for COVID-19 (coronavirus disease 2019). Here, we review the past and ongoing vaccine development efforts for clinically relevant coronavirus strains with the intention that this information helps in the development of effective and safe vaccines for COVID-19. In addition, information from naturally exposed individuals and animal models to coronavirus strains is described for the same purpose of helping into the development of effective vaccines against COVID-19.

positive: Annotation of long non-coding RNAs expressed in Collaborative Cross founder mice in response to respiratory virus infection reveals a new class of interferon-stimulated transcripts The outcome of respiratory virus infection is determined by a complex interplay of viral and host factors. Some potentially important host factors for the antiviral response, whose functions remain largely unexplored, are long non-coding RNAs (lncRNAs). Here we systematically inferred the regulatory functions of host lncRNAs in response to influenza A virus and severe acute respiratory syndrome coronavirus (SARS-CoV) based on their similarity in expression with genes of known function. We performed total RNA-Seq on viral-infected lungs from eight mouse strains, yielding a large data set of transcriptional responses. Overall 5,329 lncRNAs were differentially expressed after infection. Most of the lncRNAs were co-expressed with coding genes in modules enriched in genes associated with lung homeostasis pathways or immune response processes. Each lncRNA was further individually annotated using a rank-based method, enabling us to associate 5,295 lncRNAs to at least one gene set and to predict their potential cis effects. We validated the lncRNAs predicted to be interferon-stimulated by profiling mouse responses after interferon-α treatment. Altogether, these results provide a broad categorization of potential lncRNA functions and identify subsets of lncRNAs with likely key roles in respiratory virus pathogenesis. These data are fully accessible through the MOuse NOn-Code Lung interactive database (MONOCLdb).

positive: Understanding SARS-CoV-2-Mediated Inflammatory Responses: From Mechanisms to Potential Therapeutic Tools Currently there is no effective antiviral therapy for SARS-CoV-2 infection, which frequently leads to fatal inflammatory responses and acute lung injury. Here, we discuss the various mechanisms of SARS-CoV-mediated inflammation. We also assume that SARS-CoV-2 likely shares similar inflammatory responses. Potential therapeutic tools to reduce SARS-CoV-2-induced inflammatory responses include various methods to block FcR activation. In the absence of a proven clinical FcR blocker, the use of intravenous immunoglobulin to block FcR activation may be a viable option for the urgent treatment of pulmonary inflammation to prevent severe lung injury. Such treatment may also be combined with systemic anti-inflammatory drugs or corticosteroids. However, these strategies, as proposed here, remain to be clinically tested for effectiveness.

positive: Emerging and re-emerging coronaviruses in pigs Porcine epidemic diarrhea virus (PEDV), porcine deltacoronavirus (PDCoV), and swine acute diarrhea syndrome-coronavirus (SADS-CoV) are emerging/reemerging coronaviruses (CoVs). They cause acute gastroenteritis in neonatal piglets. Sequence analyses suggest that PEDV and SADS-CoV may have originated from bat CoVs and PDCoV from a sparrow CoV, reaffirming the interspecies transmission of CoVs. The clinical signs and pathogenesis of the three viruses are similar. Necrosis of infected intestinal epithelial cells occurs, causing villous atrophy that results in malabsorptive diarrhea. The severe diarrhea and vomiting may lead to dehydration and death of piglets. Natural infection induces protective immunity, but there is no cross-protection among the three viruses. Besides strict biosecurity measures, individual vaccines are needed for each virus for disease prevention and control.

positive: COVID-19: Immunology and treatment options Abstract The novel coronavirus SARS-CoV2 causes COVID-19, a pandemic threatening millions. As protective immunity does not exist in humans and the virus is capable of escaping innate immune responses, it can proliferate, unhindered, in primarily infected tissues. Subsequent cell death results in the release of virus particles and intracellular components to the extracellular space, which result in immune cell recruitment, the generation of immune complexes and associated damage. Infection of monocytes/macrophages and/or recruitment of uninfected immune cells can result in massive inflammatory responses later in the disease. Uncontrolled production of pro-inflammatory mediators contributes to ARDS and cytokine storm syndrome. Antiviral agents and immune modulating treatments are currently being trialled. Understanding immune evasion strategies of SARS-CoV2 and the resulting delayed massive immune response will result in the identification of biomarkers that predict outcomes as well as phenotype and disease stage specific treatments that will likely include both antiviral and immune modulating agents.

positive: SARS‐CoV‐2‐reactive interferon‐γ‐producing CD8+ T cells in patients hospitalized with coronavirus disease 2019 There is limited information on severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) T‐cell immune responses in patients with coronavirus disease 2019 (COVID‐19). Both CD4+ and CD8+ T cells may be instrumental in resolution of and protection from SARS‐CoV‐2 infection. Here, we tested 25 hospitalized patients either with microbiologically documented COVID‐19 (n = 19) or highly suspected of having the disease (n = 6) for presence of SARS‐CoV‐2‐reactive CD69+ expressing interferon‐γ (IFN‐γ) producing CD8+ T cells using flow‐cytometry for intracellular cytokine staining assay. Two sets of overlapping peptides encompassing the SARS‐CoV‐2 Spike glycoprotein N‐terminal 1 to 643 amino acid sequence and the entire sequence of SARS‐CoV‐2 M protein were used simultaneously as antigenic stimulus. Ten patients (40%) had detectable responses, displaying frequencies ranging from 0.15 to 2.7% (median of 0.57 cells/µL; range, 0.43‐9.98 cells/µL). The detection rate of SARS‐CoV‐2‐reactive IFN‐γ CD8+ T cells in patients admitted to intensive care was comparable (P = .28) to the rate in patients hospitalized in other medical wards. No correlation was found between SARS‐CoV‐2‐reactive IFN‐γ CD8+ T‐cell counts and SARS‐CoV‐2 S‐specific antibody levels. Likewise, no correlation was observed between either SARS‐CoV‐2‐reactive IFN‐γ CD8+ T cells or S‐specific immunoglobulin G‐antibody titers and blood cell count or levels of inflammatory biomarkers. In summary, in this descriptive, preliminary study we showed that SARS‐CoV‐2‐reactive IFN‐γ CD8+ T cells can be detected in a non‐negligible percentage of patients with moderate to severe forms of COVID‐19. Further studies are warranted to determine whether quantitation of these T‐cell subsets may provide prognostic information on the clinical course of COVID‐19.

positive: Highlight of Immune Pathogenic Response and Hematopathologic Effect in SARS-CoV, MERS-CoV, and SARS-Cov-2 Infection A sudden outbreak of COVID-19 caused by a novel coronavirus, SARS-CoV-2, in Wuhan, China in December 2019 quickly grew into a global pandemic, putting at risk not only the global healthcare system, but also the world economy. As the disease continues to spread rapidly, the development of prophylactic and therapeutic approaches is urgently required. Although some progress has been made in understanding the viral structure and invasion mechanism of coronaviruses that may cause severe cases of the syndrome, due to the limited understanding of the immune effects caused by SARS-CoV-2, it is difficult for us to prevent patients from developing acute respiratory distress syndrome (ARDS) and pulmonary fibrosis (PF), the major complications of coronavirus infection. Therefore, any potential treatments should focus not only on direct killing of coronaviruses and prevention strategies by vaccine development, but also on keeping in check the acute immune/inflammatory responses, resulting in ARDS and PF. In addition, potential treatments currently under clinical trials focusing on killing coronaviruses or on developing vaccines preventing coronavirus infection largely ignore the host immune response. However, taking care of SARS-CoV-2 infected patients with ARDS and PF is considered to be the major difficulty. Therefore, further understanding of the host immune response to SARS-CoV-2 is extremely important for clinical resolution and saving medication cost. In addition to a breif overview of the structure, infection mechanism, and possible therapeutic approaches, we summarized and compared the hematopathologic effect and immune responses to SARS-CoV, MERS-CoV, and SARS-CoV-2. We also discussed the indirect immune response caused by SARS and direct infection, replication, and destroying of immune cells by MERS-CoV. The molecular mechanisms of SARS-CoV and MERS-CoV infection-induced lymphopenia or cytokine storm may provide some hint toward fight against SARS-CoV-2, the novel coronavirus. This may provide guidance over using immune therapy as a combined treatment to prevent patients developing severe respiratory syndrome and largely reduce complications.

positive: The trinity of COVID-19: immunity, inflammation and intervention Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the ongoing coronavirus disease 2019 (COVID-19) pandemic. Alongside investigations into the virology of SARS-CoV-2, understanding the fundamental physiological and immunological processes underlying the clinical manifestations of COVID-19 is vital for the identification and rational design of effective therapies. Here, we provide an overview of the pathophysiology of SARS-CoV-2 infection. We describe the interaction of SARS-CoV-2 with the immune system and the subsequent contribution of dysfunctional immune responses to disease progression. From nascent reports describing SARS-CoV-2, we make inferences on the basis of the parallel pathophysiological and immunological features of the other human coronaviruses targeting the lower respiratory tract — severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV). Finally, we highlight the implications of these approaches for potential therapeutic interventions that target viral infection and/or immunoregulation.

positive: Immunogenicity, safety, and protective efficacy of an inactivated SARS-associated coronavirus vaccine in rhesus monkeys An inactivated vaccine for severe acute respiratory syndrome (SARS)-associated coronavirus (SARS-CoV) was evaluated in rhesus monkeys. The monkeys were inoculated intramuscularly (i.m.) with 0.5, 5, 50, or 5000 μg of vaccine, or PBS as control, and boosted on day 7. After 3 weeks, they were challenged with the NS-1 strain of SARS-CoV. The humoral and mucosal immune responses, clinical signs, chemical indices and viremia were monitored following the immunization and challenge. The control animals who received PBS developed atypical SAR-CoV infection after viral challenge, according to clinical, virological and pathological findings. No systematic side effects were observed in vaccinated animals post-immunization, even in at the high dose of 5000 μg. The 50 μg dosage of vaccine elicited SARS-CoV specific immune responses against viral infection as compared to the partial immunity elicited by 0.5 and 5 μg doses. The results show that this inactivated vaccine can induce effective concomitant humoral and mucosal immunity against SARS-CoV infection, is safe in monkeys, and the vaccine maybe a good candidate for clinical trials.

positive: SARS-CoV-2: Combating Coronavirus Emergence Summary The emergence and rapid global spread of SARS-CoV-2 mark the third such identification of a novel coronavirus capable of causing severe, potentially fatal disease in humans in the 21st century. As noted by Andersen et al. (Nature Medicine), the sequencing of proximal zoonotic ancestors to SARS-CoV-2 has aided in the identification of alleles that may contribute to the virus’ virulence in humans.

positive: Emergence of Novel Coronavirus and COVID-19: whether to stay or die out? The last century has witnessed several assaults from RNA viruses, resulting in millions of death throughout the world. The 21st century appears no longer an exception, with the trend continued with escalated fear of SARS coronavirus in 2002 and further concern of influenza H5N1 in 2003. A novel influenza virus created the first pandemic of the 21st century, the pandemic flu in 2009 preceded with the emergence of another deadly virus, MERS-CoV in 2012. A novel coronavirus "SARS-CoV-2" (and the disease COVID-19) emerged suddenly, causing a rapid outbreak with a moderate case fatality rate. This virus is continuing to cause health care providers grave concern due to the lack of any existing immunity in the human population, indicating their novelty and lack of previous exposure. The big question is whether this novel virus will be establishing itself in an endemic form or will it eventually die out? Endemic viruses during circulation may acquire mutations to infect naïve, as well as individual with pre-existing immunity. Continuous monitoring is strongly advisable, not only to the newly infected individuals, but also to those recovered individuals who were infected by SARS-CoV-2 as re-infection may lead to the selection of escape mutants and subsequent dissemination to the population.

positive: Vaccines for SARS-CoV-2: Lessons from Other Coronavirus Strains The emergence of the strain of coronavirus SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) and its impact on global health have made imperative the development of effective and safe vaccines for this lethal strain. SARS-CoV-2 now adds to the list of coronavirus diseases that have threatened global health, along with the SARS (severe acute respiratory syndrome) and MERS (Middle East respiratory syndrome) coronaviruses that emerged in 2002/2003 and 2012, respectively. As of April 2020, no vaccine is commercially available for these coronavirus strains. Nevertheless, the knowledge obtained from the vaccine development efforts for MERS and SARS can be of high value for COVID-19 (coronavirus disease 2019). Here, we review the past and ongoing vaccine development efforts for clinically relevant coronavirus strains with the intention that this information helps in the development of effective and safe vaccines for COVID-19. In addition, information from naturally exposed individuals and animal models to coronavirus strains is described for the same purpose of helping into the development of effective vaccines against COVID-19.

positive: Development of passive immunity against SARS-CoV-2 for management of immunodeficient patients - a perspective

positive: Reflection on lower rates of COVID-19 in children: does childhood immunizations offer unexpected protection? The incidence of COVID-19 in children and teenagers is only about 2% in China. Children had mild symptoms and hardly infected other children or adults. It is worth considering that children are the most vulnerable to respiratory pathogens, but fatal SARS-like virus had not caused severe cases among them. According to the pathological studies of COVID-19 and SARS, a sharp decrease in T lymphocytes leads to the breakdown of the immune system. The cellular immune system of children differs from that of adults may be the keystone of atypical clinical manifestations or even covert infection. The frequent childhood vaccinations and repeated pathogens infections might be resulting in trained immunity of innate immune cells, immune fitness of adaptive immune cells or cross-protection of antibodies in the children. Therefore, due to lack of specific vaccine, some vaccines for tuberculosis, influenza and pneumonia may have certain application potential for the front-line health workers in the prevention and control of COVID-19. However, for high-risk susceptible populations, such as the elderly with basic diseases such as hypertension and diabetes, it is necessary to explore the acclimatization effect of the planned immune process on their immunity to achieve the trained immunity or immune fitness, so as to improve their own antiviral ability.

positive: Protective immunity after COVID-19 has been questioned: What can we do without SARS-CoV-2-IgG detection? Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) induces a severe acute respiratory syndrome that is called COVID-19. Clinical manifestations of COVID-19 include diarrhea, pneumonia, lymphopenia, exhausted lymphocytes, and pro-inflammatory cytokine production. Immunology is part of the process of clinical evolution, but there are some questions around immunity-based protection: (1) why some infected people have only mild symptoms of the disease or are asymptomatic; (2) why delayed and weak antibody responses are associated with severe outcomes; and (3) why positivity in molecular tests does not represent protective antibody IgG. Perhaps T cell responses may be the key to solving those questions. SARS-CoV-2-specific memory T cells persist in peripheral blood and may be capable of providing effective information about protective immunity. The T cells studies can be helpful in elucidating the pathways for development of vaccines, therapies, and diagnostics for COVID-19 and for filling these immunology knowledge gaps.

positive: Recent Insight into SARS-CoV2 Immunopathology and Rationale for Potential Treatment and Preventive Strategies in COVID-19 As the outbreak of the new coronavirus (SARS-CoV-2) infection is spreading globally, great effort is being made to understand the disease pathogenesis and host factors that predispose to disease progression in an attempt to find a window of opportunity for intervention. In addition to the direct cytopathic effect of the virus, the host hyper-inflammatory response has emerged as a key factor in determining disease severity and mortality. Accumulating clinical observations raised hypotheses to explain why some patients develop more severe disease while others only manifest mild or no symptoms. So far, Covid-19 management remains mainly supportive. However, many researches are underway to clarify the role of antiviral and immunomodulating drugs in changing morbidity and mortality in patients who become severely ill. This review summarizes the current state of knowledge on the interaction between SARS-CoV-2 and the host immune system and discusses recent findings on proposed pharmacologic treatments.

positive: Protective immunity after COVID-19 has been questioned: what can we do without SARS-CoV-2-IgG detection? Abstract Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) induces a severe acute respiratory syndrome that is called COVID-19. Clinical manifestations of COVID-19 include diarrhea, pneumonia, lymphopenia, exhausted lymphocytes, and pro-inflammatory cytokine production. Immunology is part of the process of clinical evolution, but there are some questions around immunity-based protection: (1) why some infected people have only mild symptoms of the disease or are asymptomatic; (2) why delayed and weak antibody responses are associated with severe outcomes; and (3) why positivity in molecular tests does not represent protective antibody IgG. Perhaps T cell responses may be the key to solving those questions. SARS-CoV-2-specific memory T cells persist in peripheral blood and may be capable of providing effective information about protective immunity. The T cells studies can be helpful in elucidating the pathways for development of vaccines, therapies, and diagnostics for COVID-19 and for filling these immunology knowledge gaps.

positive: A national prospective cohort study of SARS/COV2 pandemic outcomes in the U.S.: The CHASING COVID Cohort Introduction: The Chasing COVID Cohort (C3) study is a US-based, geographically and socio-demographically diverse sample of adults (18 and older) enrolled into a prospective cohort study during the upswing of the U.S. COVID-19 pandemic. Methods: We used internet-based strategies to enroll C3 participants beginning March 28th, 2020. Following baseline questionnaire completion, study participants will be contacted monthly (for 6 months) to complete assessments of engagement in non-pharmaceutical interventions (e.g., use of cloth masks, avoiding large gatherings); COVID-19 symptoms; SARS/COV2 testing and diagnosis; hospitalizations; healthcare access; and uptake of health messaging. Dried blood spot (DBS) specimens will be collected at the first follow-up assessment (last week of April 2020) and at month 3 (last week of June 2020) and stored until a validated serologic test is available. Results: As of April 20, 2020, the number of people that completed the baseline survey and provided contact information for follow-up was 7,070. Participants resided in all 50 US states, the District of Columbia, Puerto Rico, and Guam. At least 24% of participants were frontline workers (healthcare and other essential workers). Twenty-three percent (23%) were 60+ years, 24% were Black or Hispanic, 52% were men, and 52% were currently employed. Nearly 20% reported recent COVID-like symptoms (cough, fever or shortness of breath) and a high proportion reported engaging in non-pharmaceutical interventions that reduce SARS/COV2 spread (93% avoided groups >20, 58% wore masks; 73% quarantined). More than half (54%) had higher risk for severe COVID-19 illness should they become infected with SARS/COV2 based on age, underlying health conditions (e.g., chronic lung disease), or daily smoking. Discussion: A geographically and socio-demographically diverse group of participants was rapidly enrolled in the C3 during the upswing of the SARS/COV2 pandemic. Strengths of the C3 include the potential for direct observation of, and risk factors for, seroconversion and incident COVID disease (among those with or without antibodies to SARS/COV2) in areas of active transmission.

positive: Cell Attachment Domains of the Porcine Epidemic Diarrhea Virus Spike Protein Are Key Targets of Neutralizing Antibodies. Porcine epidemic diarrhea virus (PEDV) causes enteric disease in pigs, resulting in significant economic losses to the swine industry worldwide. Current vaccination approaches against this emerging coronavirus are only partially effective, though natural infection protects pigs against reinfection and provides lactogenic immunity to suckling piglets. The viral spike (S) glycoprotein, responsible for receptor binding and cell entry, is the major target for neutralizing antibodies. However, knowledge of antibody epitopes, their nature and location in the spike structure, and the mechanisms by which the antibodies interfere with infection is scarce. Here we describe the generation and characterization of 10 neutralizing and nonneutralizing mouse monoclonal antibodies raised against the S1 receptor binding subunit of the S protein. By expression of different S1 protein fragments, six antibody epitope classes distributed over the five structural domains of the S1 subunit were identified. Characterization of antibodies for cross-reactivity and cross-neutralization revealed antigenic differences among PEDV strains. The epitopes of potent neutralizing antibodies segregated into two epitope classes and mapped within the N-terminal sialic acid binding domain and in the more C-terminal receptor binding domain. Antibody neutralization escape mutants displayed single amino acid substitutions that impaired antibody binding and neutralization and defined the locations of the epitopes. Our observations picture the antibody epitope landscape of the PEDV S1 subunit and reveal that its cell attachment domains are key targets of neutralizing antibodies.IMPORTANCE Porcine epidemic diarrhea virus (PEDV), an emerging porcine coronavirus, causes an economically important enteric disease in pigs. Effective PEDV vaccines for disease control are currently lacking. The spike (S) glycoprotein on the virion surface is the key player in virus cell entry and, therefore, the main target of neutralizing antibodies. To understand the antigenic landscape of the PEDV spike protein, we developed monoclonal antibodies against the spike protein's S1 receptor binding region and characterized their epitopes, neutralizing activity, and cross-reactivity toward multiple PEDV strains. Epitopes of antibodies segregated into six epitope classes dispersed over the multidomain S1 structure. Monoclonal antibodies revealed antigenic variability in B-cell epitopes between PEDV strains. The epitopes of neutralizing antibodies mapped to two distinct domains in S1 that are involved in binding to carbohydrate and proteinaceous cell surface molecules, respectively, indicating the importance of these cell attachment sites on the PEDV spike protein in eliciting a protective humoral immune response.

positive: The novel coronavirus 2019 (2019-nCoV) uses the SARS-coronavirus receptor ACE2 and the cellular protease TMPRSS2 for entry into target cells The emergence of a novel, highly pathogenic coronavirus, 2019-nCoV, in China, and its rapid national and international spread pose a global health emergency. Coronaviruses use their spike proteins to select and enter target cells and insights into nCoV-2019 spike (S)-driven entry might facilitate assessment of pandemic potential and reveal therapeutic targets. Here, we demonstrate that 2019-nCoV-S uses the SARS-coronavirus receptor, ACE2, for entry and the cellular protease TMPRSS2 for 2019-nCoV-S priming. A TMPRSS2 inhibitor blocked entry and might constitute a treatment option. Finally, we show that the serum form a convalescent SARS patient neutralized 2019-nCoV-S-driven entry. Our results reveal important commonalities between 2019-nCoV and SARS-coronavirus infection, which might translate into similar transmissibility and disease pathogenesis. Moreover, they identify a target for antiviral intervention. One sentence summary The novel 2019 coronavirus and the SARS-coronavirus share central biological properties which can guide risk assessment and intervention.

positive: Neutralizing antibody and protective immunity to SARS coronavirus infection of mice induced by a soluble recombinant polypeptide containing an N-terminal segment of the spike glycoprotein Abstract A secreted, glycosylated polypeptide containing amino acids 14 to 762 of the SARS coronavirus (SARS-CoV) spike protein and a polyhistidine tag was expressed in recombinant baculovirus-infected insect cells. Mice received the affinity-purified protein with either a saponin (QS21) or a Ribi (MPL + TDM) adjuvant subcutaneously and were challenged intranasally with SARS-CoV. Both regimens induced binding and neutralizing antibodies and protection against SARS-CoV intranasal infection. However, the best results were obtained with QS21 and protein, which provided the highest antibody as well as complete protection of the upper and lower respiratory tract.

positive: Detection of IgM and IgG antibodies in patients with coronavirus disease 2019 OBJECTIVES: This study aimed to determine the IgM and IgG responses against severe acute respiratory syndrome coronavirus (SARS‐CoV)‐2 in coronavirus disease 2019 (COVID‐19) patients with varying illness severities. METHODS: IgM and IgG antibody levels were assessed via chemiluminescence immunoassay in 338 COVID‐19 patients. RESULTS: IgM levels increased during the first week after SARS‐CoV‐2 infection, peaked 2 weeks and then reduced to near‐background levels in most patients. IgG was detectable after 1 week and was maintained at a high level for a long period. The positive rates of IgM and/or IgG antibody detections were not significantly different among the mild, severe and critical disease groups. Severe and critical cases had higher IgM levels than mild cases, whereas the IgG level in critical cases was lower than those in both mild and severe cases. This might be because of the high disease activity and/or a compromised immune response in critical cases. The IgM antibody levels were slightly higher in deceased patients than recovered patients, but IgG levels in these groups did not significantly differ. A longitudinal detection of antibodies revealed that IgM levels decreased rapidly in recovered patients, whereas in deceased cases, either IgM levels remained high or both IgM and IgG were undetectable during the disease course. CONCLUSION: Quantitative detection of IgM and IgG antibodies against SARS‐CoV‐2 quantitatively has potential significance for evaluating the severity and prognosis of COVID‐19.

positive: Priming with SARS CoV S DNA and boosting with SARS CoV S epitopes specific for CD4(+) and CD8(+) T cells promote cellular immune responses Cellular immune response plays an important role in antiviral immunity. In our previous study, immunization of mice with severe acute respiratory syndrome coronavirus (SARS CoV) spike (S) DNA vaccine could induce both humoral and cellular immunity in response to a pool of entire overlapping S peptides. Identification of functional dominant epitopes in SARS CoV S protein for T cells is crucial for further understanding of cellular immune responses elicited by SARS CoV S DNA vaccine. In present study, mice were immunized with SARS CoV S DNA vaccine. Subsequently, a pool of 17–19 mers overlapped SARS CoV S peptides, which served as immunogens, were scanned to identify the specific epitopes for T cells. Two H-2(d) restricted CD4(+) T epitopes, N60 (S435–444) and P152 (S1111–1127), and two H-2(d) restricted CD8(+) T cell epitopes, N50 (S365–374) and P141 (S1031–1047) were identified by three different methods, enzyme-linked immunosorbent assay (ELISA), enzyme linked immunospot assay (ELISPOT) and fluorescence activated cell sorter (FACS). The dominant CD4(+) T cell epitope (N60) and CD8(+) T cell epitope (N50) located in the receptor-binding domain (RBD) of SARS CoV S protein, which mediated virus combining and fusing to susceptible cells. Importantly, our novel finding is that mice primed with SARS S DNA vaccine and boosted with T cell epitopes (N50 and N60) could promote antigen specific CD4(+) and CD8(+) T cell immune responses. Our study provides valuable information for the design of vaccine for SARS study.

positive: SARS: future research and vaccine Summary Severe acute respiratory syndrome (SARS) is a new infectious disease of the 21st century that has pandemic potential. A novel coronavirus (CoV) was identified as its aetiological agent and its genome was sequenced within months of the World Health Organisation issuing a global threat on SARS. The high morbidity and mortality of this potentially pandemic infection demands a rapid research response to develop effective antiviral treatment and vaccine. This will depend on understanding the pathogenesis and immune response to SARS CoV. Further understanding of the ecology of SARS CoV in human and animals will help prevent future cross species transmission. Likewise for the super-spreading events, clarification of the underlying reasons will be important to prevent a large scale outbreak of SARS. Lastly it is of utmost importance that international research collaboration should be strengthened to deal with SARS and any other emerging infectious disease that can seriously threaten our future.

positive: Structural basis for potent cross-neutralizing human monoclonal antibody protection against lethal human and zoonotic severe acute respiratory syndrome coronavirus challenge. Severe acute respiratory syndrome coronavirus (SARS-CoV) emerged in 2002, and detailed phylogenetic and epidemiological analyses have suggested that it originated from animals. The spike (S) glycoprotein has been identified as a major component of protective immunity, and 23 different amino acid changes were noted during the expanding epidemic. Using a panel of SARS-CoV recombinants bearing the S glycoproteins from isolates representing the zoonotic and human early, middle, and late phases of the epidemic, we identified 23 monoclonal antibodies (MAbs) with neutralizing activity against one or multiple SARS-CoV spike variants and determined the presence of at least six distinct neutralizing profiles in the SARS-CoV S glycoprotein. Four of these MAbs showed cross-neutralizing activity against all human and zoonotic S variants in vitro, and at least three of these were mapped in distinct epitopes using escape mutants, structure analyses, and competition assays. These three MAbs (S109.8, S227.14, and S230.15) were tested for use in passive vaccination studies using lethal SARS-CoV challenge models for young and senescent mice with four different homologous and heterologous SARS-CoV S variants. Both S227.14 and S230.15 completely protected young and old mice from weight loss and virus replication in the lungs for all viruses tested, while S109.8 completely protected mice from weight loss and clinical signs in the presence of viral titers. We conclude that a single human MAb can confer broad protection against lethal challenge with multiple zoonotic and human SARS-CoV isolates, and we identify a robust cocktail formulation that targets distinct epitopes and minimizes the likely generation of escape mutants.

positive: Lessons for COVID-19 immunity from other coronavirus infections Abstract A key goal to controlling COVID-19 is developing an effective vaccine. Development of a vaccine requires knowledge of what constitutes a protective immune response and also features that might be pathogenic. Protective and pathogenic aspects of the response to SARS-CoV-2 are not well understood, partly because the virus has infected humans for only 6 months. However, insight into coronavirus immunity can be informed by previous studies of immune responses to non-human coronaviruses, to common cold coronaviruses, and to SARS-CoV and MERS-CoV. Here we review the literature describing these responses and discuss their relevance to the SARS-CoV-2 immune response.

positive: COVIEdb: A database for potential immune epitopes of coronaviruses 2019 novel coronavirus (2019-nCoV) has caused large-scale pandemic COVID-19 all over the world. It’s essential to find out which parts of the 2019-nCoV sequence are recognized by human immune system for vaccine development. And for the prevention of the potential outbreak of similar coronaviruses in the future, vaccines against immunogenic epitopes shared by different human coronaviruses are essential. Here we predict all the potential B/T-cell epitopes for SARS-CoV, MERS-CoV, 2019-nCoV and RaTG13-CoV based on the protein sequences. We found YFKYWDQTY in ORF1ab protein, VYDPLQPEL and TVYDPLQPEL in spike (S) protein might be pan-coronavirus targets for vaccine development. All the predicted results are stored in a database COVIEdb (http://biopharm.zju.edu.cn/coviedb/).

positive: Stage of Gestation at Porcine Epidemic Diarrhea Virus Infection of Pregnant Swine Impacts Maternal Immunity and Lactogenic Immune Protection of Neonatal Suckling Piglets During pregnancy, the maternal immune response changes dramatically over the course of gestation. This has implications for generation of lactogenic immunity and subsequent protection in suckling neonates against enteric viral infections. For example, porcine epidemic diarrhea virus (PEDV) is an alphacoronavirus that causes acute diarrhea in neonatal piglets. Due to the high virulence of PEDV and the naïve, immature immune system of neonatal suckling piglets, passive lactogenic immunity to PEDV induced during pregnancy, via the gut-mammary gland (MG)-secretory IgA (sIgA) axis, is critical for piglet protection. However, the anti-PEDV immune response during pregnancy and stage of gestation required to optimally stimulate the gut-MG-sIgA axis is undefined. We hypothesize that there is a gestational window in which non-lethal PEDV infection of pregnant gilts influences maximum lymphocyte mucosal trafficking to the MG, resulting in optimal passive lactogenic protection in suckling piglets. To understand how the stages of gestation affect maternal immune responses to PEDV, three groups of gilts were orally infected with PEDV in the first, second or third trimester. Control (mock) gilts were inoculated with medium in the third trimester. To determine if lactogenic immunity correlated with protection, all piglets were PEDV-challenged at 3–5 days postpartum. PEDV infection of gilts at different stages of gestation significantly affected multiple maternal systemic immune parameters prepartum, including cytokines, B cells, PEDV antibodies (Abs), and PEDV antibody secreting cells (ASCs). Pregnant second trimester gilts had significantly higher levels of circulating PEDV IgA and IgG Abs and ASCs and PEDV virus neutralizing (VN) Abs post PEDV infection. Coinciding with the significantly higher PEDV Ab responses in second trimester gilts, the survival rate of their PEDV-challenged piglets was 100%, compared with 87.2, 55.9, and 5.7% for first, third, and mock litters, respectively. Additionally, piglet survival positively correlated with PEDV IgA Abs and ASCs and VN Abs in milk and PEDV IgA and IgG Abs in piglet serum. Our findings have implications for gestational timing of oral attenuated PEDV maternal vaccines, whereby PEDV intestinal infection in the second trimester optimally stimulated the gut-MG-sIgA axis resulting in 100% lactogenic immune protection in suckling piglets.

positive: Animal Models and Vaccines for SARS-CoV Infection We summarize findings of SARS-CoV infections in several animal models each of which support viral replication in lungs accompanied by histopathological changes and/or clinical signs of illness to varying degrees. New findings are reported on SARS-CoV replication and associated pathology in two additional strains (C57BL/6 and 129S6) of aged mice. We also provide new comparative data on viral replication and associated pathology following infection of golden Syrian hamsters with various SARS-CoV strains and report the levels of neutralizing antibody titers following these infections and the cross-protective efficacy of infection with these strains in protecting against heterologous challenge. Finally, we summarize findings of a variety of vaccine approaches and discuss the available in vitro and in vivo data addressing the potential for disease enhancement following re-infection in animals previously vaccinated against or infected with SARS-CoV.

positive: The Conserved Coronavirus Macrodomain Promotes Virulence and Suppresses the Innate Immune Response during Severe Acute Respiratory Syndrome Coronavirus Infection ADP-ribosylation is a common posttranslational modification that may have antiviral properties and impact innate immunity. To regulate this activity, macrodomain proteins enzymatically remove covalently attached ADP-ribose from protein targets. All members of the Coronavirinae, a subfamily of positive-sense RNA viruses, contain a highly conserved macrodomain within nonstructural protein 3 (nsp3). However, its function or targets during infection remain unknown. We identified several macrodomain mutations that greatly reduced nsp3’s de-ADP-ribosylation activity in vitro. Next, we created recombinant severe acute respiratory syndrome coronavirus (SARS-CoV) strains with these mutations. These mutations led to virus attenuation and a modest reduction of viral loads in infected mice, despite normal replication in cell culture. Further, macrodomain mutant virus elicited an early, enhanced interferon (IFN), interferon-stimulated gene (ISG), and proinflammatory cytokine response in mice and in a human bronchial epithelial cell line. Using a coinfection assay, we found that inclusion of mutant virus in the inoculum protected mice from an otherwise lethal SARS-CoV infection without reducing virus loads, indicating that the changes in innate immune response were physiologically significant. In conclusion, we have established a novel function for the SARS-CoV macrodomain that implicates ADP-ribose in the regulation of the innate immune response and helps to demonstrate why this domain is conserved in CoVs.

positive: Prevention and treatment of COVID‐19 disease by controlled modulation of innate immunity The recent outbreak of coronavirus disease 2019 (COVID‐19), triggered by the severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) poses an enormous threat to global public health and economies. Human coronaviruses normally cause no or mild respiratory disease but in the past two decades, potentially fatal coronavirus infections have emerged, causing respiratory tract illnesses such as pneumonia and bronchitis. These include severe acute respiratory syndrome coronavirus (SARS‐CoV), followed by the Middle East respiratory syndrome coronavirus (MERS‐CoV), and recently the SARS‐CoV‐2 coronavirus outbreak which emerged in Wuhan, China, in December 2019. Currently, most COVID‐19 patients receive traditional supportive care including breathing assistance. To halt the ongoing spread of the pandemic SARS‐CoV‐2 coronavirus and rescue individual patients, established drugs and new therapies are under evaluation. Since it will be some time until a safe and effective vaccine will be available, the immediate priority is to harness innate immunity to accelerate early antiviral immune responses. Secondly since excessive inflammation is a major cause of pathology, targeted anti‐inflammatory responses are being evaluated to reduce inflammation‐induced damage to the respiratory tract and cytokine storms. Here, we highlight prominent immunotherapies at various stages of development which aim for augmented anti‐coronavirus immunity and reduction of pathological inflammation. This article is protected by copyright. All rights reserved

positive: Immune and bioinformatics identification of T cell and B cell epitopes in the protein structure of SARS-CoV-2: A Systematic Review The beginning of 2020 was marked as the emergence of a COVID-19 outbreak caused by a new coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Currently, there is no vaccine or approved treatment for this infectious virus so the invention of an efficient vaccine is certainly a high priority. Some studies have employed several techniques to facilitate the combination of the immunoinformatics approach and comparative genomic approach in order to determine the potential peptides for designing the T-cell epitope-based peptide vaccine using the 2019-nCoV envelope protein as a target. Via screening the bioimmunoinformatic SARS-CoV2 derived B-cell and T-cell epitopes within the basic immunogenic of SARS-CoV2 proteins, we presented a set of inferred B-cell and T-cell epitopes from the spike (S) and nucleocapsid (N) proteins with high antigenicity and without allergenic property or toxic effects. Our findings provide a screened set of epitopes that can be introduced as potential targets for developing peptide vaccines against the SARS-CoV-2 virus.

positive: Epidemiology of seasonal coronaviruses: Establishing the context for COVID-19 emergence Public health preparedness for coronavirus disease 2019 (COVID-19) is challenging in the absence of setting-specific epidemiological data. Here we describe the epidemiology of seasonal human coronaviruses (sCoVs) and other cocirculating viruses in the West of Scotland, UK. We analyzed routine diagnostic data for >70,000 episodes of respiratory illness tested molecularly for multiple respiratory viruses between 2005 and 2017. Statistical associations with patient age and sex differed between CoV-229E, CoV-OC43 and CoV-NL63. Furthermore, the timing and magnitude of sCoV outbreaks did not occur concurrently and coinfections were not reported. With respect to other cocirculating respiratory viruses, we found evidence of positive, rather than negative, interactions with sCoVs. These findings highlight the importance of considering cocirculating viruses in the differential diagnosis of COVID-19. Further work is needed to establish the occurrence/degree of cross-protective immunity conferred across sCoVs and with COVID-19, as well as the role of viral coinfection in COVID-19 disease severity.

positive: Covid-19: loss of bridging between innate and adaptive immunity? COVID-19 has spread to most countries in the world. However, there are some striking differences in how COVID-19 is behaving in different age groups. While data on COVID-19 is limited, children appear to be less susceptible to severe disease. These unique characteristics may be considered as a potential link to understanding the immune system and response in COVID-19 and lead to an effective cure to the disease. We suggest a possible role of loss of bridging between innate and adaptive immunity in COVID-19 and a potential treatment modality also discussed.

positive: Investigation of Antibody-Dependent Enhancement (ADE) of SARS coronavirus infection and its role in pathogenesis of SARS

positive: Innate Immunity in Coronavirus Infection ;врожденный Иммунитет При Коронавирусной Инфекции Coronaviruses (CoVs) comprise a polymorphic group of respiratory viruses causing acute inflammatory diseases in domestic and agricultural animals (chicken, pig, buffalo, cat, dog) Until recently, this infection in humans was mainly observed during the autumn-winter period and characterized by a mild, often asymptomatic, course The situation changed dramatically in 2003, when SARS outbreak caused by pathogenic CoV (SARS-CoV) was recorded in China A decade later, a new CoV outbreak occurred in the form of the Middle East respiratory syndrome (MERS-CoV), whereas in December 2019, SARS-CoV-2 (COVID-19) cases were recorded, which transformed within the first months of 2020 into the pandemic In all three cases, CoV disease led to severe bronchopulmonary lesions, varying from dry, debilitating cough to acute respiratory distress syndrome (ARDS) At the same time, multiple changes in innate immunity were noted most often manifested as a pronounced inflammatory reaction in the lower respiratory tract, featured by damaged type II pneumocytes, apoptosis, hyalinization of alveolar membranes, focal or generalized pulmonary edema Destructive processes in the respiratory tract were accompanied by migration of monocytes/macrophages and granulocyte neutrophils to the inflammatory focus Such events were accompanied by production of pro-inflammatory cytokines, which magnitude could ascend up to a cytokine storm SARS-CoV is characterized by symptoms of secondary immunosuppression, manifested by the late onset of interferon production and activation of NLRP3 inflammasomes â€“ the key inflammatory factor The reason for such reaction may be accounted for by CoV arsenal containing extensive set of structural and inflammatory proteins exerting pro-inflammatory and immunosuppressive properties Delayed IFN production allowed CoV to replicate actively and freely, and when type I IFN synthesis was eventually triggered, its activity was detrimental and accompanied by an aggravated infection course Thus, SARS can surely be referred to immune-dependent infections with a marked immunopathological component The purpose of this review was to describe some mechanisms underlying formation of innate immune response to infection caused by pathogenic coronaviruses SARS-CoV, MERS-CoV and SARS-CoV-2 (COVID-19) ;ÐšÐ¾Ñ€Ð¾Ð½Ð°Ð²Ð¸Ñ€ÑƒÑÑ‹ (CoV) Ð¿Ñ€ÐµÐ´ÑÑ‚Ð°Ð²Ð»ÑÑŽÑ‚ ÑÐ¾Ð±Ð¾Ð¹ Ð¿Ð¾Ð»Ð¸Ð¼Ð¾Ñ€Ñ„Ð½ÑƒÑŽ Ð³Ñ€ÑƒÐ¿Ð¿Ñƒ Ñ€ÐµÑÐ¿Ð¸Ñ€Ð°Ñ‚Ð¾Ñ€Ð½Ñ‹Ñ… Ð²Ð¸Ñ€ÑƒÑÐ¾Ð², Ð²Ñ‹Ð·Ñ‹Ð²Ð°ÑŽÑ‰Ð¸Ñ… Ð¾ÑÑ‚Ñ€Ñ‹Ðµ Ð²Ð¾ÑÐ¿Ð°Ð»Ð¸Ñ‚ÐµÐ»ÑŒÐ½Ñ‹Ðµ Ð·Ð°Ð±Ð¾Ð»ÐµÐ²Ð°Ð½Ð¸Ñ Ñƒ Ð´Ð¾Ð¼Ð°ÑˆÐ½Ð¸Ñ… Ð¸ ÑÐµÐ»ÑŒÑÐºÐ¾Ñ…Ð¾Ð·ÑÐ¹ÑÑ‚Ð²ÐµÐ½Ð½Ñ‹Ñ… Ð¶Ð¸Ð²Ð¾Ñ‚Ð½Ñ‹Ñ… (ÐºÑƒÑ€Ñ‹, ÑÐ²Ð¸Ð½ÑŒÐ¸, Ð±ÑƒÐ¹Ð²Ð¾Ð»Ñ‹, ÐºÐ¾ÑˆÐºÐ¸, ÑÐ¾Ð±Ð°ÐºÐ¸) Ð£ Ð»ÑŽÐ´ÐµÐ¹ Ð¸Ð½Ñ„ÐµÐºÑ†Ð¸Ñ Ð´Ð¾ Ð½ÐµÐ´Ð°Ð²Ð½ÐµÐ³Ð¾ Ð²Ñ€ÐµÐ¼ÐµÐ½Ð¸ Ð½Ð°Ð±Ð»ÑŽÐ´Ð°Ð»Ð¾ÑÑŒ Ð¿Ñ€ÐµÐ¸Ð¼ÑƒÑ‰ÐµÑÑ‚Ð²ÐµÐ½Ð½Ð¾ Ð² Ð¾ÑÐµÐ½Ð½Ðµ-Ð·Ð¸Ð¼Ð½Ð¸Ð¹ Ð¿ÐµÑ€Ð¸Ð¾Ð´ Ð¸ Ñ…Ð°Ñ€Ð°ÐºÑ‚ÐµÑ€Ð¸Ð·Ð¾Ð²Ð°Ð»Ð°ÑÑŒ Ð»ÐµÐ³ÐºÐ¸Ð¼, Ð·Ð°Ñ‡Ð°ÑÑ‚ÑƒÑŽ Ð±ÐµÑÑÐ¸Ð¼Ð¿Ñ‚Ð¾Ð¼Ð½Ñ‹Ð¼, Ñ‚ÐµÑ‡ÐµÐ½Ð¸ÐµÐ¼ Ð¡Ð¸Ñ‚ÑƒÐ°Ñ†Ð¸Ñ Ñ€ÐµÐ·ÐºÐ¾ Ð¸Ð·Ð¼ÐµÐ½Ð¸Ð»Ð°ÑÑŒ, Ð² 2003 Ð³Ð¾Ð´Ñƒ, ÐºÐ¾Ð³Ð´Ð° Ð² ÐšÐ¸Ñ‚Ð°Ðµ Ð±Ñ‹Ð»Ð° Ð·Ð°Ñ€ÐµÐ³Ð¸ÑÑ‚Ñ€Ð¸Ñ€Ð¾Ð²Ð°Ð½Ð° Ð²ÑÐ¿Ñ‹ÑˆÐºÐ° Ð°Ñ‚Ð¸Ð¿Ð¸Ñ‡Ð½Ð¾Ð¹ Ð¿Ð½ÐµÐ²Ð¼Ð¾Ð½Ð¸Ð¸, Ð²Ñ‹Ð·Ð²Ð°Ð½Ð½Ð¾Ð¹ Ð¿Ð°Ñ‚Ð¾Ð³ÐµÐ½Ð½Ñ‹Ð¼ CoV (SARS-CoV) Ð¡Ð¿ÑƒÑÑ‚Ñ 10 Ð»ÐµÑ‚ Ð²Ð¾Ð·Ð½Ð¸ÐºÐ»Ð° Ð½Ð¾Ð²Ð°Ñ Ð²ÑÐ¿Ñ‹ÑˆÐºÐ° CoV Ð² Ð²Ð¸Ð´Ðµ Ð±Ð»Ð¸Ð¶Ð½ÐµÐ²Ð¾ÑÑ‚Ð¾Ñ‡Ð½Ð¾Ð³Ð¾ Ñ€ÐµÑÐ¿Ð¸Ñ€Ð°Ñ‚Ð¾Ñ€Ð½Ð¾Ð³Ð¾ ÑÐ¸Ð½Ð´Ñ€Ð¾Ð¼Ð° (MERS-CoV), Ð° Ð² Ð´ÐµÐºÐ°Ð±Ñ€Ðµ 2019 Ð³ Ð¾Ñ‚Ð¼ÐµÑ‡ÐµÐ½Ñ‹ ÑÐ»ÑƒÑ‡Ð°Ð¸ SARS-CoV-2 (COVID-19), Ñ‚Ñ€Ð°Ð½ÑÑ„Ð¾Ñ€Ð¼Ð¸Ñ€Ð¾Ð²Ð°Ð²ÑˆÐ¸ÐµÑÑ Ð² Ð¿ÐµÑ€Ð²Ñ‹Ðµ Ð¼ÐµÑÑÑ†Ñ‹ 2020 Ð³ Ð² Ð¿Ð°Ð½Ð´ÐµÐ¼Ð¸ÑŽ Ð’Ð¾ Ð²ÑÐµÑ… Ñ‚Ñ€ÐµÑ… ÑÐ»ÑƒÑ‡Ð°ÑÑ… Ð·Ð°Ð±Ð¾Ð»ÐµÐ²Ð°Ð½Ð¸Ðµ Ñ‡Ð°ÑÑ‚Ð¾ Ð¿Ñ€Ð¸Ð²Ð¾Ð´Ð¸Ð»Ð¾ Ðº Ñ‚ÑÐ¶ÐµÐ»Ñ‹Ð¼Ð¸ Ð±Ñ€Ð¾Ð½Ñ…Ð¾Ð»ÐµÐ³Ð¾Ñ‡Ð½Ñ‹Ð¼Ð¸ Ð¿Ð¾Ñ€Ð°Ð¶ÐµÐ½Ð¸ÑÐ¼Ð¸, Ð²Ð°Ñ€ÑŒÐ¸Ñ€Ð¾Ð²Ð°Ð²ÑˆÐ¸Ð¼ Ð¾Ñ‚ ÑÑƒÑ…Ð¾Ð³Ð¾ Ð¸Ð·Ð½ÑƒÑ€Ð¸Ñ‚ÐµÐ»ÑŒÐ½Ð¾Ð³Ð¾ ÐºÐ°ÑˆÐ»Ñ Ð´Ð¾ Ð¾ÑÑ‚Ñ€Ð¾Ð³Ð¾ Ñ€ÐµÑÐ¿Ð¸Ñ€Ð°Ñ‚Ð¾Ñ€Ð½Ð¾Ð³Ð¾ Ð´Ð¸ÑÑ‚Ñ€ÐµÑÑ ÑÐ¸Ð½Ð´Ñ€Ð¾Ð¼Ð° (ÐžÐ Ð”Ð¡) ÐžÐ´Ð½Ð¾Ð²Ñ€ÐµÐ¼ÐµÐ½Ð½Ð¾ Ñ ÑÑ‚Ð¸Ð¼ Ð¾Ñ‚Ð¼ÐµÑ‡ÐµÐ½Ñ‹ Ð¼Ð½Ð¾Ð¶ÐµÑÑ‚Ð²ÐµÐ½Ð½Ñ‹Ðµ Ð¸Ð·Ð¼ÐµÐ½ÐµÐ½Ð¸Ñ Ð² ÑÐ¸ÑÑ‚ÐµÐ¼Ðµ Ð²Ñ€Ð¾Ð¶Ð´ÐµÐ½Ð½Ð¾Ð³Ð¾ Ð¸Ð¼Ð¼ÑƒÐ½Ð¸Ñ‚ÐµÑ‚Ð Ñ‡Ð°Ñ‰Ðµ Ð²ÑÐµÐ³Ð¾ Ð² Ð²Ð¸Ð´Ðµ Ð²Ñ‹Ñ€Ð°Ð¶ÐµÐ½Ð½Ð¾Ð¹ Ð²Ð¾ÑÐ¿Ð°Ð»Ð¸Ñ‚ÐµÐ»ÑŒÐ½Ð¾Ð¹ Ñ€ÐµÐ°ÐºÑ†Ð¸Ð¸ Ð² Ð½Ð¸Ð¶Ð½Ð¸Ñ… Ð´Ñ‹Ñ…Ð°Ñ‚ÐµÐ»ÑŒÐ½Ñ‹Ñ… Ð¿ÑƒÑ‚ÑÑ…, Ð¿Ñ€Ð¾ÑÐ²Ð»ÑÐ²ÑˆÐ¸ÐµÑÑ Ð¿Ð¾Ð²Ñ€ÐµÐ¶Ð´ÐµÐ½Ð¸ÐµÐ¼ Ð¿Ð½ÐµÐ²Ð¼Ð¾Ñ†Ð¸Ñ‚Ð¾Ð² II Ð¿Ð¾Ñ€ÑÐ´ÐºÐ°, ÑÐ²Ð»ÐµÐ½Ð¸ÑÐ¼Ð¸ Ð°Ð¿Ð¾Ð¿Ñ‚Ð¾Ð·Ð°, Ð³Ð¸Ð°Ð»Ð¸Ð½Ð¸Ð·Ð°Ñ†Ð¸ÐµÐ¹ Ð°Ð»ÑŒÐ²ÐµÐ¾Ð»ÑÑ€Ð½Ñ‹Ñ… Ð¼ÐµÐ¼Ð±Ñ€Ð°Ð½, Ð¾Ñ‡Ð°Ð³Ð¾Ð²Ñ‹Ð¼ Ð¸Ð»Ð¸ Ð³ÐµÐ½ÐµÑ€Ð°Ð»Ð¸Ð·Ð¾Ð²Ð°Ð½Ð½Ñ‹Ð¼ Ð¾Ñ‚ÐµÐºÐ¾Ð¼ Ð»ÐµÐ³ÐºÐ¸Ñ… Ð”ÐµÑÑ‚Ñ€ÑƒÐºÑ‚Ð¸Ð²Ð½Ñ‹Ðµ Ð¿Ñ€Ð¾Ñ†ÐµÑÑÑ‹ Ð² Ñ€ÐµÑÐ¿Ð¸Ñ€Ð°Ñ‚Ð¾Ñ€Ð½Ð¾Ð¼ Ð¾Ñ‚Ð´ÐµÐ»Ðµ ÑÐ¾Ð¿Ñ€Ð¾Ð²Ð¾Ð¶Ð´Ð°Ð»Ð¸ÑÑŒ Ð¼Ð¸Ð³Ñ€Ð°Ñ†Ð¸ÐµÐ¹ Ð² Ð¾Ñ‡Ð°Ð³ Ð²Ð¾ÑÐ¿Ð°Ð»Ð¸Ñ‚ÐµÐ»ÑŒÐ½Ñ‹Ñ… Ð¼Ð¾Ð½Ð¾Ñ†Ð¸Ñ‚Ð¾Ð²/Ð¼Ð°ÐºÑ€Ð¾Ñ„Ð°Ð³Ð¾Ð² Ð¸ Ð³Ñ€Ð°Ð½ÑƒÐ»Ð¾Ñ†Ð¸Ñ‚Ð°Ñ€Ð½Ñ‹Ñ… Ð½ÐµÐ¹Ñ‚Ñ€Ð¾Ñ„Ð¸Ð»Ð¾Ð² ÐÐ° Ñ„Ð¾Ð½Ðµ Ð¿ÐµÑ€ÐµÑ‡Ð¸ÑÐ»ÐµÐ½Ð½Ñ‹Ñ… ÑÐ²Ð»ÐµÐ½Ð¸Ð¹ Ð½Ð°Ð±Ð»ÑŽÐ´Ð°Ð»Ð°ÑÑŒ Ð²Ñ‹Ñ€Ð°Ð±Ð¾Ñ‚ÐºÐ° Ð¿Ñ€Ð¾Ð²Ð¾ÑÐ¿Ð°Ð»Ð¸Ñ‚ÐµÐ»ÑŒÐ½Ñ‹Ñ… Ñ†Ð¸Ñ‚Ð¾ÐºÐ¸Ð½Ð¾Ð², Ð¸Ð½Ñ‚ÐµÐ½ÑÐ¸Ð²Ð½Ð¾ÑÑ‚ÑŒ ÐºÐ¾Ñ‚Ð¾Ñ€Ð¾Ð¹ Ð¼Ð¾Ð¶ÐµÑ‚ Ð½Ð°Ñ€Ð°ÑÑ‚Ð°Ñ‚ÑŒ Ð´Ð¾ Ñ†Ð¸Ñ‚Ð¾ÐºÐ¸Ð½Ð¾Ð²Ð¾Ð³Ð¾ ÑˆÑ‚Ð¾Ñ€Ð¼Ð° Ð”Ð»Ñ SARS-CoV Ñ…Ð°Ñ€Ð°ÐºÑ‚ÐµÑ€Ð½Ñ‹ ÑÐ¸Ð¼Ð¿Ñ‚Ð¾Ð¼Ñ‹ Ð²Ñ‚Ð¾Ñ€Ð¸Ñ‡Ð½Ð¾Ð¹ Ð¸Ð¼Ð¼ÑƒÐ½Ð¾Ð´ÐµÐ¿Ñ€ÐµÑÑÐ¸Ð¸, Ð¿Ñ€Ð¾ÑÐ²Ð»ÑÐ²ÑˆÐ¸ÐµÑÑ Ð² Ð¿Ð¾Ð·Ð´Ð½ÐµÐ¼ Ð½Ð°Ñ‡Ð°Ð»Ðµ ÑÐ¸Ð½Ñ‚ÐµÐ·Ð° Ð¸Ð½Ñ‚ÐµÑ€Ñ„ÐµÑ€Ð¾Ð½Ð¾Ð² Ð¸ Ð°ÐºÑ‚Ð¸Ð²Ð°Ñ†Ð¸Ð¸ ÐºÐ»ÑŽÑ‡ÐµÐ²Ð¾Ð³Ð¾ Ñ„Ð°ÐºÑ‚Ð¾Ñ€Ð° Ð²Ð¾ÑÐ¿Ð°Ð»ÐµÐ½Ð¸Ñ â€“ NLRP3 Ð¸Ð½Ñ„Ð»Ð°Ð¼Ð¼Ð°ÑÐ¾Ð¼Ñ‹ ÐŸÑ€Ð¸Ñ‡Ð¸Ð½Ð¾Ð¹ Ð¿Ð¾Ð´Ð¾Ð±Ð½Ð¾Ð¹ Ñ€ÐµÐ°ÐºÑ†Ð¸Ð¸ ÑÐ²Ð»ÑÐµÑ‚ÑÑ Â«Ð²Ð¾Ð¾Ñ€ÑƒÐ¶ÐµÐ½Ð½Ð¾ÑÑ‚ÑŒÂ» CoV Ð¾Ð±ÑˆÐ¸Ñ€Ð½Ñ‹Ð¼ Ð½Ð°Ð±Ð¾Ñ€Ð¾Ð¼ ÑÑ‚Ñ€ÑƒÐºÑ‚ÑƒÑ€Ð½Ñ‹Ñ… Ð¸ Ð²Ð¾ÑÐ¿Ð°Ð»Ð¸Ñ‚ÐµÐ»ÑŒÐ½Ñ‹Ñ… Ð±ÐµÐ»ÐºÐ¾Ð², Ð¾Ð±Ð»Ð°Ð´Ð°ÑŽÑ‰Ð¸Ñ… Ð¿Ñ€Ð¾Ð²Ð¾ÑÐ¿Ð°Ð»Ð¸Ñ‚ÐµÐ»ÑŒÐ½Ñ‹Ð¼Ð¸ Ð¸ Ð¸Ð¼Ð¼ÑƒÐ½Ð¾Ð´ÐµÐ¿Ñ€ÐµÑÑÐ¸Ð²Ð½Ñ‹Ð¼Ð¸ ÑÐ²Ð¾Ð¹ÑÑ‚Ð²Ð°Ð¼Ð¸ ÐžÑ‚ÑÑ€Ð¾Ñ‡ÐµÐ½Ð½Ñ‹Ð¹ ÑÐ¸Ð½Ñ‚ÐµÐ· IFN Ð¿Ð¾Ð·Ð²Ð¾Ð»ÑÐ» Ð²Ð¸Ñ€ÑƒÑÑƒ Ð°ÐºÑ‚Ð¸Ð²Ð½Ð¾ Ð¸ Ð±ÐµÑÐ¿Ñ€ÐµÐ¿ÑÑ‚ÑÑ‚Ð²ÐµÐ½Ð½Ð¾ Ñ€ÐµÐ¿Ð»Ð¸Ñ†Ð¸Ñ€Ð¾Ð²Ð°Ñ‚ÑŒ, Ð° ÐºÐ¾Ð³Ð´Ð° Ð²ÑÐµ Ð¶Ðµ Ð¾Ñ€Ð³Ð°Ð½Ð¸Ð·Ð¼ Ð·Ð°Ð¿ÑƒÑÐºÐ°Ð» ÑÐ¸Ð½Ñ‚ÐµÐ· IFN I, ÐµÐ³Ð¾ Ð´ÐµÐ¹ÑÑ‚Ð²Ð¸Ðµ Ð¾ÐºÐ°Ð·Ñ‹Ð²Ð°Ð»Ð¾ÑÑŒ Ð²Ñ€ÐµÐ´Ð½Ñ‹Ð¼ Ð¸ ÑÐ¾Ð¿Ñ€Ð¾Ð²Ð¾Ð¶Ð´Ð°Ð»Ð¾ÑÑŒ ÑƒÑ‚ÑÐ¶ÐµÐ»ÐµÐ½Ð¸ÐµÐ¼ Ñ‚ÐµÑ‡ÐµÐ½Ð¸Ñ Ð¸Ð½Ñ„ÐµÐºÑ†Ð¸Ð¸ Ð¢Ð°ÐºÐ¸Ð¼ Ð¾Ð±Ñ€Ð°Ð·Ð¾Ð¼, SARS Ð¼Ð¾Ð¶Ð½Ð¾ Ñ Ð¿Ð¾Ð»Ð½Ñ‹Ð¼ Ð¾ÑÐ½Ð¾Ð²Ð°Ð½Ð¸ÐµÐ¼ Ð¾Ñ‚Ð½ÐµÑÑ‚Ð¸Ðº Ñ‡Ð¸ÑÐ»Ñƒ Ð¸Ð¼Ð¼ÑƒÐ½Ð¾-Ð·Ð°Ð²Ð¸ÑÐ¸Ð¼Ñ‹Ñ… Ð¸Ð½Ñ„ÐµÐºÑ†Ð¸Ð¹ Ñ Ð²Ñ‹Ñ€Ð°Ð¶ÐµÐ½Ð½Ñ‹Ð¼ Ð¸Ð¼Ð¼ÑƒÐ½Ð¾Ð¿Ð°Ñ‚Ð¾Ð»Ð¾Ð³Ð¸Ñ‡ÐµÑÐºÐ¸Ð¼ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚Ð¾Ð¼ Ð¦ÐµÐ»ÑŒ ÑÑ‚Ð¾Ð³Ð¾ Ð¾Ð±Ð·Ð¾Ñ€Ð° Ð¾Ð¿Ð¸ÑÐ°Ñ‚ÑŒ Ð½ÐµÐºÐ¾Ñ‚Ð¾Ñ€Ñ‹Ðµ Ð¼ÐµÑ…Ð°Ð½Ð¸Ð·Ð¼Ñ‹ Ñ„Ð¾Ñ€Ð¼Ð¸Ñ€Ð¾Ð²Ð°Ð½Ð¸Ñ Ð²Ñ€Ð¾Ð¶Ð´ÐµÐ½Ð½Ð¾Ð³Ð¾ Ð¸Ð¼Ð¼ÑƒÐ½Ð½Ð¾Ð³Ð¾ Ð¾Ñ‚Ð²ÐµÑ‚Ð° Ð½Ð° Ð¸Ð½Ñ„Ð¸Ñ†Ð¸Ñ€Ð¾Ð²Ð°Ð½Ð¸Ðµ Ð¿Ð°Ñ‚Ð¾Ð³ÐµÐ½Ð½Ñ‹Ð¼Ð¸ ÐºÐ¾Ñ€Ð¾Ð½Ð°Ð²Ð¸Ñ€ÑƒÑÐ°Ð¼Ð¸: SARS-CoV, MERS-CoV Ð¸ CoV-2 (COVID-19)

positive: SARS-CoV-2 infection protects against rechallenge in rhesus macaques An understanding of protective immunity to SARS-CoV-2 is critical for vaccine and public health strategies aimed at ending the global COVID-19 pandemic. A key unanswered question is whether infection with SARS-CoV-2 results in protective immunity against re-exposure. We developed a rhesus macaque model of SARS-CoV-2 infection and observed that macaques had high viral loads in the upper and lower respiratory tract, humoral and cellular immune responses, and pathologic evidence of viral pneumonia. Following initial viral clearance, animals were rechallenged with SARS-CoV-2 and showed 5 log10 reductions in median viral loads in bronchoalveolar lavage and nasal mucosa compared with primary infection. Anamnestic immune responses following rechallenge suggested that protection was mediated by immunologic control. These data show that SARS-CoV-2 infection induced protective immunity against re-exposure in nonhuman primates.

positive: COVID-19: what has been learned and to be learned about the novel coronavirus disease The outbreak of Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome (SARS) coronavirus 2 (SARS-CoV-2), has thus far killed over 3,000 people and infected over 80,000 in China and elsewhere in the world, resulting in catastrophe for humans. Similar to its homologous virus, SARS-CoV, which caused SARS in thousands of people in 2003, SARS-CoV-2 might also be transmitted from the bats and causes similar symptoms through a similar mechanism. However, COVID-19 has lower severity and mortality than SARS but is much more transmissive and affects more elderly individuals than youth and more men than women. In response to the rapidly increasing number of publications on the emerging disease, this article attempts to provide a timely and comprehensive review of the swiftly developing research subject. We will cover the basics about the epidemiology, etiology, virology, diagnosis, treatment, prognosis, and prevention of the disease. Although many questions still require answers, we hope that this review helps in the understanding and eradication of the threatening disease.

positive: The many faces of the anti-COVID immune response The novel 2019 strain of coronavirus is a source of profound morbidity and mortality worldwide. Compared with recent viral outbreaks, COVID-19 infection has a relatively high mortality rate, the reasons for which are not entirely clear. Furthermore, treatment options for COVID-19 infection are currently limited. In this Perspective, we explore the contributions of the innate and adaptive immune systems to both viral control as well as toxicity during COVID-19 infections and offer suggestions to both understand and therapeutically modulate anti-COVID immunity.

positive: Next Generation Sequencing of T and B cell receptor repertoires from COVID-19 patients showed signatures associated with severity of disease Summary We profiled adaptive immunity in COVID-19 patients with active infection or after recovery and created a repository of currently >14 million B and T cell receptor (BCR, TCR) sequences from blood of these patients. The B cell response showed converging IGHV3-driven BCR clusters closely associated with SARS-CoV-2 antibodies. Clonality and skewing of TCR repertoires was associated with interferon type I and III responses, early CD4+ and CD8+ T cell activation and counterregulation by the coreceptors BTLA, Tim-3, PD-1, TIGIT and CD73. Tfh, Th17-like and nonconventional (but not classical anti-viral) Th1 cell polarizations were induced. SARS-CoV-2-specific T cell responses were driven by TCR clusters shared between patients with a characteristic trajectory of clonotypes and traceability over the disease course. Our data provide fundamental insight into adaptive immunity to SARS-CoV-2 with the actively updated repository providing a resource for the scientific community urgently needed to inform therapeutic concepts and vaccine development.

positive: Induction of neutralising antibodies and cellular immune responses against SARS coronavirus by recombinant measles viruses Live attenuated recombinant measles viruses (rMV) expressing a codon-optimised spike glycoprotein (S) or nucleocapsid protein (N) of severe acute respiratory syndrome-associated coronavirus (SARS-CoV) were generated (rMV-S and rMV-N). Both recombinant viruses stably expressed the corresponding SARS-CoV proteins, grew to similar end titres as the parental strain and induced high antibody titres against MV and the vectored SARS-CoV antigens (S and N) in transgenic mice susceptible to measles infection. The antibodies induced by rMV-S had a high neutralising effect on SARS-CoV as well as on MV. Moreover, significant N-specific cellular immune responses were measured by IFN-γ ELISPOT assays. The pre-existence of anti-MV antibodies induced by the initial immunisation dose did not inhibit boost of anti-S and anti-N antibodies. Immunisations comprising a mixture of rMV-S and rMV-N induced immune responses similar in magnitude to that of vaccine components administered separately. These data support the suitability of MV as a bivalent candidate vaccine vector against MV and emerging viruses such as SARS-CoV.

positive: Spiking Pandemic Potential: Structural and Immunological aspects of SARS-CoV-2 SUMMARY SARS-Coronavirus-2 (SARS-CoV-2) causes Coronavirus disease 2019 (COVID-19), an infectious respiratory disease causing thousands of deaths and overwhelming public health systems. The international spread of SARS-CoV-2 is associated with the ease of global travel, and societal dynamics, immunologic naiveté of the host population, and muted innate immune responses. Based on these factors and the expanding geographic scale of the disease, the WHO declared the COVID-19 outbreak a pandemic–the first caused by a coronavirus. In this review, we summarize the current epidemiological status of COVID-19 and consider the virological and immunological lessons, animal models, and tools developed in response to prior SARS-CoV and MERS-CoV outbreaks that can serve as resources for development of SARS-CoV-2 therapeutics and vaccines. In particular, we discuss structural insights into the SARS-CoV-2 spike protein, a major determinant of transmissibility, and discuss key molecular aspects that will aid in understanding and fighting this new global threat.

positive: COVID‐19 vaccines: knowing the unknown Vaccine development against SARS‐CoV‐2 has drawn attention around the globe due to the exploding pandemic. Although COVID‐19 is caused by a new coronavirus, SARS‐CoV‐2, previous research on other coronavirus vaccines, such as FIPV, SARS and MERS, has provided valuable information for the rapid development of COVID‐19 vaccine. However, important knowledge gaps remain – some are specific to SARS‐CoV‐2, others are fundamental to immunology and vaccinology. Here we discuss areas that need to be addressed for COVID‐19 vaccine development, and what can be learned from examples of vaccine development in the past. Since the beginning of the outbreak, the research progress on COVID‐19 has been remarkable. We are therefore optimistic about the rapid development of COVID‐19 vaccine. This article is protected by copyright. All rights reserved

positive: Human T-cell immunity against the emerging and re-emerging viruses Over the past decade, we have seen an alarming number of high-profile outbreaks of newly emerging and re-emerging viruses. Recent outbreaks of avian influenza viruses, Middle East respiratory syndrome coronaviruses, Zika virus and Ebola virus present great threats to global health. Considering the pivotal role of host T-cell immunity in the alleviation of symptoms and the clearance of viruses in patients, there are three issues to be primarily concerned about T-cell immunity when a new virus emerges: first, does the population possess pre-existing T-cells against the new virus through previous infections of genetically relevant viruses; second, does a proper immune response arise in the patients to provide protection through an immunopathogenic effect; lastly, how long can the virus-specific immune memory persist. Herein, we summarize the current updates on the characteristics of human T-cell immunological responses against recently emerged or re-emerged viruses, and emphasize the necessity for timely investigation on the T-cell features of these viral diseases, which may provide beneficial recommendations for clinical diagnosis and vaccine development.

positive: Broadening of Neutralization Activity to Directly Block a Dominant Antibody-Driven SARS-Coronavirus Evolution Pathway Phylogenetic analyses have provided strong evidence that amino acid changes in spike (S) protein of animal and human SARS coronaviruses (SARS-CoVs) during and between two zoonotic transfers (2002/03 and 2003/04) are the result of positive selection. While several studies support that some amino acid changes between animal and human viruses are the result of inter-species adaptation, the role of neutralizing antibodies (nAbs) in driving SARS-CoV evolution, particularly during intra-species transmission, is unknown. A detailed examination of SARS-CoV infected animal and human convalescent sera could provide evidence of nAb pressure which, if found, may lead to strategies to effectively block virus evolution pathways by broadening the activity of nAbs. Here we show, by focusing on a dominant neutralization epitope, that contemporaneous- and cross-strain nAb responses against SARS-CoV spike protein exist during natural infection. In vitro immune pressure on this epitope using 2002/03 strain-specific nAb 80R recapitulated a dominant escape mutation that was present in all 2003/04 animal and human viruses. Strategies to block this nAb escape/naturally occurring evolution pathway by generating broad nAbs (BnAbs) with activity against 80R escape mutants and both 2002/03 and 2003/04 strains were explored. Structure-based amino acid changes in an activation-induced cytidine deaminase (AID) “hot spot” in a light chain CDR (complementarity determining region) alone, introduced through shuffling of naturally occurring non-immune human VL chain repertoire or by targeted mutagenesis, were successful in generating these BnAbs. These results demonstrate that nAb-mediated immune pressure is likely a driving force for positive selection during intra-species transmission of SARS-CoV. Somatic hypermutation (SHM) of a single VL CDR can markedly broaden the activity of a strain-specific nAb. The strategies investigated in this study, in particular the use of structural information in combination of chain-shuffling as well as hot-spot CDR mutagenesis, can be exploited to broaden neutralization activity, to improve anti-viral nAb therapies, and directly manipulate virus evolution.

positive: SARS-CoV-2 Antibody Testing – Questions to be asked ABSTRACT SARS-CoV-2 infection and development of COVID-19 disease presents a major healthcare challenge of global dimensions. Laboratory diagnostics of infected patients, and the assessment of immunity against the SARS-CoV-2 virus presents a major cornerstone in handling the pandemic. Currently there is an increase in demand of antibody testing and a large number of tests are already marketed or in the late stage of development. However, the interpretation of test results depends on many variables and factors, including sensitivity, specificity, potential cross-reactivity and cross-protectivity; the diagnostic value of antibodies of different isotypes, the use of antibody testing in identification of acutely ill patients or in epidemiological settings. In this article the recently established COVID-19 Task Force of the German Society for Clinical Chemistry and Laboratory Medicine (DGKL) addresses these issues based on the currently available datasets in this rapidly moving field.

positive: Immune responses to porcine epidemic diarrhea virus (PEDV) in swine and protection against subsequent infection Understanding the immune responses against Porcine epidemic diarrhea virus (PEDV) is important to prevent infection and to design control strategies. We evaluated both systemic and mucosal immune responses to PEDV in pigs and assessed if prior exposure to virus protects against re-infection. Three-week-old pigs were infected with PEDV and immune response in blood, intestine, and mesenteric lymph node (MLN) was evaluated. At 30 dpi, virus exposed pigs were challenged with a field isolate of PEDV and immune response at 5 d post challenge was evaluated. We found that PEDV RNA persists in the intestine even after fecal shedding of the virus was stopped at 28 dpi and pigs previously exposed to PEDV are protected from virus shedding after re-infection. PEDV infection induced both humoral and cell mediated immune response with an increase in PEDV specific IgA and IgG antibodies in intestine and serum. Flow cytometry analysis showed a significantly higher frequency of B cells and lower frequency of T cells at 4 dpi. The frequency of CD4/CD8 double positive (DP) memory T cells was significantly increased in the MLN of challenged animals. These studies may provide further insights into understanding the mucosal immune response to PEDV and its role in protection against disease.

positive: High-Accuracy Multiplexed SARS-CoV-2 Antibody Assay with Avidity and Saliva Capability on a Nano-Plasmonic Platform The outbreak and rapid spread of SARS-CoV-2 virus has led to a dire global pandemic with millions of people infected and ~ 400,000 deaths thus far. Highly accurate detection of antibodies for COVID-19 is an indispensable part of the effort to combat the pandemic1,2. Here we developed two-plex antibody detection against SARS-CoV-2 spike proteins3 (the S1 subunit and receptor binding domain RBD) in human serum and saliva on a near-infrared nano-plasmonic gold (pGOLD) platform4–8. By testing nearly 600 serum samples, pGOLD COVID-19 assay achieved ~ 99.78 % specificity for detecting both IgG and IgM with 100 % sensitivity in sera collected > 14 days post disease symptom onset, with zero cross-reactivity to other diseases. Two-plex correlation analysis revealed higher binding of serum IgM to RBD than to S1. IgG antibody avidity toward multiple antigens were measured, shedding light on antibody maturation in COVID-19 patients and affording a powerful tool for differentiating recent from remote infections and identifying re-infection by SARS-CoV-2. Just as important, due to high analytical sensitivity, the pGOLD COVID-19 assay detected minute amounts of antibodies in human saliva, offering the first non-invasive detection of SARS-CoV-2 antibodies.

positive: COVID-19 vaccines: A race against time in the middle of death and devastation! The COVID-19 has turned in to a global human tragedy and economic devastation. Governments have implemented lockdown measures, blocked international travel, and enforced other public containment measures to mitigate the virus morbidity and mortality. As of today, no drug has the power to fight the infection and bring normalcy to the utter chaos. This leaves us with only one choice namely an effective and safe vaccine that shall be manufactured as soon as possible and available to all countries and populations affected by the pandemic at an affordable price. There has been an unprecedented fast track path taken in Research & Development (R&D) by the World community for developing an effective and safe vaccine. Platform technology has been exploited to develop candidate vaccines in a matter of days to weeks and as of now, 108 such vaccines are available. Six of these vaccines have entered clinical trials. As clinical trials are ‘rate-limiting’ and ‘time-consuming’, many innovative methods are in practice for a fast track. These include parallel phase I-II trials and obtaining efficacy data from phase IIb trials. Human ‘challenge experiments’ to confirm efficacy in humans is under serious consideration. The availability of the COVID-19 vaccine has become a race against time in the middle of death and devastation. There is an atmosphere of tremendous hype around the COVID-19 vaccine and developers are using every moment to make claims, which remain unverified. However, concerns are raised about a rush to deploy a COVID-19 vaccine. Applying ‘Quick fix’ and ‘short cuts’ can lead to errors with disastrous consequences.

positive: Human coronavirus reinfection dynamics: lessons for SARS-CoV-2 In the current SARS-CoV-2 pandemic a key unsolved question is the quality and duration of acquired immunity in recovered individuals. This is crucial to solve, however SARS-CoV-2 has circulated for under five months, precluding a direct study. We therefore monitored 10 subjects over a time span of 35 years (1985-2020), providing a total of 2473 follow up person-months, and determined a) their antibody levels following infection by any of the four seasonal human coronaviruses, and b) the time period after which reinfections by the same virus can occur. An alarmingly short duration of protective immunity to coronaviruses was found by both analyses. We saw frequent reinfections at 12 months post-infection and a substantial reduction in antibody levels as soon as 6 months post-infection.

positive: Potential antiviral options against SARS-CoV-2 infection As of June 2020, the number of people infected with severe acute respiratory coronavirus 2 (SARS-CoV-2) continues to skyrocket, with more than 6,5 million cases worldwide. Both the World Health Organization (WHO) and United Nations (UN) has highlighted the need for better control of SARS-CoV-2 infections. However, developing novel virus-specific vaccines, monoclonal antibodies and antiviral drugs against SARS-CoV-2 can be time-consuming and costly. Convalescent sera and safe-in-man broad-spectrum antivirals (BSAAs) are readily available treatment options. Here we developed a neutralization assay using SARS-CoV-2 strain and Vero-E6 cells. We identified most potent sera from recovered patients for treatment of SARS-CoV-2-infected patients. We also screened 136 safe-in-man broad-spectrum antivirals against SARS-CoV-2 infection in Vero-E6 cells and identified nelfinavir, salinomycin, amodiaquine, obatoclax, emetine and homoharringtonine. We found that combinations of virus-directed nelfinavir along with host-directed amodiaquine exhibited the highest synergy. Finally, we developed a website to disseminate the knowledge on available and emerging treatments of COVID-19.

positive: Antibody dynamics to SARS-CoV-2 in Asymptomatic and Mild COVID-19 patients Humoral immunity in asymptomatic infections with SARS-CoV-2 has not been well established. 63 healthy contacts, 63 asymptomatic individuals, and 51 mild patients were enrolled in this study and screened using nucleic acid testing (NAT) and commercial kits of serum IgM and IgG antibodies against recombinant nucleoprotein (N) and spike (S) proteins of SARS-CoV-2. Asymptomatic and mild patients were classified into at least four types based on NAT and serological tests, especially 81% and 25.4% negative NAT but positive IgM/IgG responses, respectively. Antibody dynamics were further demonstrated by IgM and IgG profile responses to SARS-CoV-2 proteome. IgM antibody responses against S1 were elicited in asymptomatic individuals as early to the seventh day after exposure and peaked on days from 17d to 25d, which might be used as early diagnostic biomarkers. Moreover, asymptomatic individuals evoked weaker S1 specific IgM and neutralizing antibody responses than mild patients. Most importantly, S1 specific IgM/IgG responses and the titers of neutralizing antibody in asymptomatic individuals gradually vanished in two months. Our findings might have important implications for serological survey, public health and immunization strategy.

positive: Neutralizing antibody responses to SARS-CoV-2 in a COVID-19 recovered patient cohort and their implications Background The COVID-19 pandemic caused by SARS-CoV-2 coronavirus threatens global public health. Currently, neutralizing antibodies (NAbs) versus this virus are expected to correlate with recovery and protection of this disease. However, the characteristics of these antibodies have not been well studied in association with the clinical manifestations in patients. Methods Plasma collected from 175 COVID-19 recovered patients with mild symptoms were screened using a safe and sensitive pseudotyped-lentiviral-vector-based neutralization assay. Spike-binding antibody in plasma were determined by ELISA using RBD, S1, and S2 proteins of SARS-CoV-2. The levels and the time course of SARS-CoV-2-specific NAbs and the spike-binding antibodies were monitored at the same time. Findings SARS-CoV-2 NAbs were unable to cross-reactive with SARS-CoV virus. SARS-CoV-2-specific NAbs were detected in patients from day 10-15 after the onset of the disease and remained thereafter. The titers of NAb among these patients correlated with the spike-binding antibodies targeting S1, RBD, and S2 regions. The titers of NAbs were variable in different patients. Elderly and middle-age patients had significantly higher plasma NAb titers (P<0.0001) and spike-binding antibodies (P=0.0003) than young patients. Notably, among these patients, there were ten patients whose NAb titers were under the detectable level of our assay (ID50: < 40); while in contrast, two patients, showed very high titers of NAb, with ID50 :15989 and 21567 respectively. The NAb titers were positive correlated with plasma CRP levels but negative correlated with the lymphocyte counts of patients at the time of admission, indicating an association between humoral response and cellular immune response. Interpretation The variations of SARS-CoV-2 specific NAbs in recovered COVID-19 patients may raise the concern about the role of NAbs on disease progression. The correlation of NAb titers with age, lymphocyte counts, and blood CRP levels suggested that the interplay between virus and host immune response in coronavirus infections should be further explored for the development of effective vaccine against SARS-CoV-2 virus. Furthermore, titration of NAb is helpful prior to the use of convalescent plasma for prevention or treatment. Funding Ministry of Science and Technology of China, National Natural Science Foundation of China, Shanghai Municipal Health Commission, and Chinese Academy of Medical Sciences

positive: Measles-derived vaccines to prevent emerging viral diseases Abstract Infectious disease epidemics match wars and natural disasters in their capacity to threaten lives and damage economies. Like SARS previously and Zika recently, the Ebola crisis in 2015 showed how vulnerable the world is to these epidemics, with over 11,000 people dying in the outbreak. In addition to causing immense human suffering, these epidemics particularly affect low- and middle-income countries. Many of these deadly infectious diseases that have epidemic potential can become global health emergencies in the absence of effective vaccines. But very few vaccines against these threats have been developed to create proven medical products. The measles vaccine is an efficient, live attenuated, replicating virus that has been safely administered to 2 billion children over the last 40 years, affording life-long protection after a single dose. Taking advantage of these characteristics, this attenuated virus was transformed into a versatile chimeric or recombinant vaccine vector with demonstrated proof-of-principle in humans and a preclinical track record of rapid adaptability and effectiveness for a variety of pathogens. Clinical trials have shown the safety and immunogenicity of this vaccine platform in individuals with preexisting immunity to measles. This review describes the potential of this platform to develop new vaccines against emerging viral diseases.

positive: Modulation of the immune response to the severe acute respiratory syndrome spike glycoprotein by gene-based and inactivated virus immunization. Although the initial isolates of the severe acute respiratory syndrome (SARS) coronavirus (CoV) are sensitive to neutralization by antibodies through their spike (S) glycoprotein, variants of S have since been identified that are resistant to such inhibition. Optimal vaccine strategies would therefore make use of additional determinants of immune recognition, either through cellular or expanded, cross-reactive humoral immunity. Here, the cellular and humoral immune responses elicited by different combinations of gene-based and inactivated viral particles with various adjuvants have been assessed. The T-cell response was altered by different prime-boost immunizations, with the optimal CD8 immunity induced by DNA priming and replication-defective adenoviral vector boosting. The humoral immune response was enhanced most effectively through the use of inactivated virus with adjuvants, either MF59 or alum, and was associated with stimulation of the CD4 but not the CD8 response. The use of inactivated SARS virus with MF59 enhanced the CD4 and antibody response even after gene-based vaccination. Because both cellular and humoral immune responses are generated by gene-based vaccination and inactivated viral boosting, this strategy may prove useful in the generation of SARS-CoV vaccines.

positive: Cross-reactive antibody response between SARS-CoV-2 and SARS-CoV infections The World Health Organization has recently declared the ongoing outbreak of COVID-19, which is caused by a novel coronavirus SARS-CoV-2, as pandemic. There is currently a lack of knowledge in the antibody response elicited from SARS-CoV-2 infection. One major immunological question is concerning the antigenic differences between SARS-CoV-2 and SARS-CoV. We address this question by using plasma from patients infected by SARS-CoV-2 or SARS-CoV, and plasma obtained from infected or immunized mice. Our results show that while cross-reactivity in antibody binding to the spike protein is common, cross-neutralization of the live viruses is rare, indicating the presence of non-neutralizing antibody response to conserved epitopes in the spike. Whether these non-neutralizing antibody responses will lead to antibody-dependent disease enhancement needs to be addressed in the future. Overall, this study not only addresses a fundamental question regarding the antigenicity differences between SARS-CoV-2 and SARS-CoV, but also has important implications in vaccine

positive: Expansion of SARS-CoV-2-specific Antibody-secreting Cells and Generation of Neutralizing Antibodies in Hospitalized COVID-19 Patients Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged in late 2019 and has since become a global pandemic. Pathogen-specific antibodies are typically a major predictor of protective immunity, yet B cell and antibody responses during COVID-19 are not fully understood. Here, we analyzed antibody-secreting cell (ASC) and antibody responses in twenty hospitalized COVID-19 patients. The patients exhibited typical symptoms of COVID-19, and presented with reduced lymphocyte numbers and increased T cell and B cell activation. Importantly, we detected an expansion of SARS-CoV-2 nucleocapsid protein-specific ASCs in all twenty COVID-19 patients using a multicolor FluoroSpot assay. Out of the 20 patients, 16 had developed SARS-CoV-2-neutralizing antibodies by the time of inclusion in the study. SARS-CoV-2-specific IgA, IgG and IgM antibody levels positively correlated with SARS-CoV-2-neutralizing antibody titers, suggesting that SARS-CoV-2-specific antibody levels may reflect the titers of neutralizing antibodies in COVID-19 patients during the acute phase of infection. Lastly, we showed that interleukin 6 (IL-6) and C-reactive protein (CRP) concentrations were higher in serum of patients who were hospitalized for longer, supporting the recent observations that IL-6 and CRP could be used to predict COVID-19 severity. Altogether, this study constitutes a detailed description of clinical and immunological parameters in twenty COVID-19 patients, with a focus on B cell and antibody responses, and provides tools to study immune responses to SARS-CoV-2 infection and vaccination.

positive: Cross-protection against a human enteric coronavirus and a virulent bovine enteric coronavirus in gnotobiotic calves. A group 2 human coronavirus designated HECV-4408 was isolated from a child with acute diarrhea and is antigenically and genetically more closely related to bovine coronavirus (BCoV) than to human coronavirus OC43 (X. M. Zhang, W. Herbst, K. G. Kousoulas, and J. Storz, J. Med. Virol. 44:152-161, 1994). To determine whether HECV-4408 infects gnotobiotic calves and induces cross-protective immunity against the virulent enteric BCoV DB2 strain, gnotobiotic calves (n = 4) were orally inoculated with HECV-4408 and then challenged with BCoV DB2 at postinoculation day (PID) 21. All calves inoculated with HECV-4408 developed diarrhea at PID 3 to 4 lasting 5 to 9 days. Fecal and nasal virus shedding were first detected by reverse transcription-PCR at PID 3 to 4 and at PID 2 to 4, respectively. After challenge with bovine coronavirus, no diarrhea or virus shedding was detected in calves inoculated with HECV-4408, but a mock-inoculated calf developed diarrhea and fecal and nasal shedding. Fecal immunoglobulin A (IgA) and serum IgG antibodies were first detected at PID 7 and PID 14, respectively. At postchallenge day 7, serum IgG and fecal IgA antibody titers remained the same or increased only twofold compared to prechallenge titers. An additional two gnotobiotic calves were inoculated with HECV-4408 and euthanized at PID 5. Moderate villous atrophy was observed in the small intestines, and viral antigen was detected in villous enterocytes of the small and large intestines by immunohistochemistry. These results support and extend the previous report that HECV-4408 is likely a variant of bovine coronavirus. They confirm its infectivity for calves and complete cross-protection against a bovine coronavirus (DB2 strain) showing 98.2% amino acid identity to HECV-4408 in the S protein.

positive: Review of Viral Testing (Polymerase Chain Reaction) and Antibody/Serology Testing for Severe Acute Respiratory Syndrome-Coronavirus-2 for the Intensivist OBJECTIVE: As the severe acute respiratory syndrome-coronavirus-2 pandemic develops, assays to detect the virus and infection caused by it are needed for diagnosis and management. To describe to clinicians how each assay is performed, what each assay detects, and the benefits and limitations of each assay. DATA SOURCES: Published literature and internet. STUDY SELECTION: As well done, relevant and recent as possible. DATA EXTRACTION: Sources were read to extract data from them. DATA SYNTHESIS: Was synthesized by all coauthors. CONCLUSIONS: Available assays test for current or previous severe acute respiratory syndrome-coronavirus-2 infection. Nucleic acid assays such as quantitative, or real-time, polymerase chain reaction and loop-mediated isothermal amplification are ideal for acute diagnosis with polymerase chain reaction testing remaining the “gold standard” to diagnose acute infection by severe acute respiratory syndrome-coronavirus-2, specifically the presence of viral RNA. Assays that detect serum antibodies can theoretically diagnose both acute and remote infection but require time for the patient to develop immunity and may detect nonspecific antibodies. Antibody assays that quantitatively measure neutralizing antibodies are needed to test efficacy of convalescent plasma therapy but are more specialized.

positive: How is immunosuppressive status affecting children and adults in SARS-CoV-2 infection? A systematic review Abstract Objectives SARS-CoV-2 infection has now a global resonance. Data on how COVID-19 is affecting immunocompromised patients are however few. With our study we aimed to systematically review the current knowledge on SARS-CoV-2 cases in children and adults with immunosuppression, to evaluate outcomes in this special population. Methods A systematic review of literature was carried out to identify relevant articles, searching the EMBASE, Medline, and Google Scholar databases. Studies reporting data on pre-defined outcomes and related to immunosuppressed adults and children with SARS-CoV-2 were included. Results Sixteen relevant articles were identified with 110 immunosuppressed patients, mostly presenting cancer, along with transplantation and immunodeficiency. Cancer was more often associated with a more severe course, but not necessarily with a bad prognosis. Our data show that both children and adults with immunosuppression seem to have a favorable disease course, as compared to the general population. Conclusion Immunosuppressed patients with COVID-19 seem to be few in relation to the overall figures, and to present a favorable outcome as compared to other comorbidities. This might be explained by a hypothetical protective role of a weaker immune response, determining a milder disease presentation and thus underdiagnosis. Nevertheless, surveillance on this special population should be encouraged.

positive: SARS-CoV-2, “common cold” coronaviruses’ cross-reactivity and “herd immunity”: The razor of Ockham (1285-1347)?

positive: Heterologous immunity between viruses. Immune memory responses to previously encountered pathogens can sometimes alter the immune response to and the course of infection of an unrelated pathogen by a process known as heterologous immunity. This response can lead to enhanced or diminished protective immunity and altered immunopathology. Here, we discuss the nature of T-cell cross-reactivity and describe matrices of epitopes from different viruses eliciting cross-reactive CD8(+) T-cell responses. We examine the parameters of heterologous immunity mediated by these cross-reactive T cells during viral infections in mice and humans. We show that heterologous immunity can disrupt T-cell memory pools, alter the complexity of the T-cell repertoire, change patterns of T-cell immunodominance, lead to the selection of viral epitope-escape variants, alter the pathogenesis of viral infections, and, by virtue of the private specificity of T-cell repertoires within individuals, contribute to dramatic variations in viral disease. We propose that heterologous immunity is an important factor in resistance to and variations of human viral infections and that issues of heterologous immunity should be considered in the design of vaccines.

positive: Immune responses against severe acute respiratory syndrome coronavirus induced by virus-like particles in mice Virus-like particles (VLPs) represent a promising vaccine against severe acute respiratory syndrome coronavirus (SARS CoV). In this study, recombinant baculovirus vAcS and vAcME were constructed to express the S protein and the M and E proteins of SARS CoV, respectively. Electron microscope analysis demonstrated the formation of VLPs in vAcME and vAcS coinfected insect cells. Mice immunized four times with VLPs developed high antibody titres against SARS CoV. In addition, VLPs elicited cell-mediated immunity as demonstrated by enhanced interferon-γ and interleukin-4 production. VLPs also conferred protective immunity against the infection of Spike protein pseudotyped murine leukaemia virus. Our findings demonstrate that SARS CoV VLPs are immunogenic and can elicit strong SARS CoV-specific humoral and cellular immune responses in mice. This is the first study describing the immunogenicity of SARS CoV VLPs, providing valuable data for developing a protective vaccine against SARS CoV infection.

positive: Systemic and mucosal antibody secretion specific to SARS-CoV-2 during mild versus severe COVID-19 Background Infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes an acute illness termed coronavirus disease 2019 (COVID-19). Humoral immune responses likely play an important role in containing SARS-CoV-2, however, the determinants of SARS-CoV-2-specific antibody responses are unclear. Methods Using immunoassays specific for the SARS-CoV-2 spike protein, we determined SARS-CoV-2-specific immunoglobulin A (IgA) and immunoglobulin G (IgG) in sera and mucosal fluids of two cohorts, including patients with quantitative reverse-transcriptase polymerase chain reaction (RT-qPCR)-confirmed SARS-CoV-2 infection (n = 56; median age 61 years) with mild versus severe COVID-19, and SARS-CoV-2-exposed healthcare workers (n = 109; median age 36 years) with or without symptoms and tested negative or positive by RT-qPCR. Findings On average, SARS-CoV-2-specific serum IgA titers in mild COVID-19 cases became positive eight days after symptom onset and were often transient, whereas serum IgG levels remained negative or reached positive values 9–10 days after symptom onset. Conversely, patients with severe COVID-19 showed a highly significant increase of SARS-CoV-2-specific serum IgA and IgG titers as a function of duration since symptom onset, independent of patient age and comorbidities. Very high levels of SARS-CoV-2-specific serum IgA correlated with severe acute respiratory distress syndrome (ARDS). Interestingly, some of the SARS-CoV-2-exposed healthcare workers with negative SARS-CoV-2-specific IgA and IgG serum titers had detectable SARS-CoV-2-specific IgA antibodies in their nasal fluids and tears. Moreover, SARS-CoV-2-specific IgA levels in nasal fluids of these healthcare workers were inversely correlated with patient age. Interpretation These data show that systemic IgA and IgG production against SARS-CoV-2 develops mainly in severe COVID-19, with very high IgA levels seen in patients with severe ARDS, whereas mild disease may be associated with transient serum titers of SARS-CoV-2-specific antibodies but stimulate mucosal SARS-CoV-2-specific IgA secretion. The findings suggest four grades of antibody responses dependent on COVID-19 severity.

positive: Two-way antigenic cross-reactivity between severe acute respiratory syndrome coronavirus (SARS-CoV) and group 1 animal CoVs is mediated through an antigenic site in the N-terminal region of the SARS-CoV nucleoprotein. In 2002, severe acute respiratory syndrome-associated coronavirus (SARS-CoV) emerged in humans, causing a global epidemic. By phylogenetic analysis, SARS-CoV is distinct from known CoVs and most closely related to group 2 CoVs. However, no antigenic cross-reactivity between SARS-CoV and known CoVs was conclusively and consistently demonstrated except for group 1 animal CoVs. We analyzed this cross-reactivity by an enzyme-linked immunosorbent assay (ELISA) and Western blot analysis using specific antisera to animal CoVs and SARS-CoV and SARS patient convalescent-phase or negative sera. Moderate two-way cross-reactivity between SARS-CoV and porcine CoVs (transmissible gastroenteritis CoV [TGEV] and porcine respiratory CoV [PRCV]) was mediated through the N but not the spike protein, whereas weaker cross-reactivity occurred with feline (feline infectious peritonitis virus) and canine CoVs. Using Escherichia coli-expressed recombinant SARS-CoV N protein and fragments, the cross-reactive region was localized between amino acids (aa) 120 to 208. The N-protein fragments comprising aa 360 to 412 and aa 1 to 213 reacted specifically with SARS convalescent-phase sera but not with negative human sera in ELISA; the fragment comprising aa 1 to 213 cross-reacted with antisera to animal CoVs, whereas the fragment comprising aa 360 to 412 did not cross-react and could be a potential candidate for SARS diagnosis. Particularly noteworthy, a single substitution at aa 120 of PRCV N protein diminished the cross-reactivity. We also demonstrated that the cross-reactivity is not universal for all group 1 CoVs, because HCoV-NL63 did not cross-react with SARS-CoV. One-way cross-reactivity of HCoV-NL63 with group 1 CoVs was localized to aa 1 to 39 and at least one other antigenic site in the N-protein C terminus, differing from the cross-reactive region identified in SARS-CoV N protein. The observed cross-reactivity is not a consequence of a higher level of amino acid identity between SARS-CoV and porcine CoV nucleoproteins, because sequence comparisons indicated that SARS-CoV N protein has amino acid identity similar to that of infectious bronchitis virus N protein and shares a higher level of identity with bovine CoV N protein within the cross-reactive region. The TGEV and SARS-CoV N proteins are RNA chaperons with long disordered regions. We speculate that during natural infection, antibodies target similar short antigenic sites within the N proteins of SARS-CoV and porcine group 1 CoVs that are exposed to an immune response. Identification of the cross-reactive and non-cross-reactive N-protein regions allows development of SARS-CoV-specific antibody assays for screening animal and human sera.

positive: ChAdOx1 and MVA based vaccine candidates against MERS-CoV elicit neutralising antibodies and cellular immune responses in mice The Middle East respiratory syndrome coronavirus (MERS-CoV) has infected more than 1900 humans, since 2012. The syndrome ranges from asymptomatic and mild cases to severe pneumonia and death. The virus is believed to be circulating in dromedary camels without notable symptoms since the 1980s. Therefore, dromedary camels are considered the only animal source of infection. Neither antiviral drugs nor vaccines are approved for veterinary or medical use despite active research on this area. Here, we developed four vaccine candidates against MERS-CoV based on ChAdOx1 and MVA viral vectors, two candidates per vector. All vaccines contained the full-length spike gene of MERS-CoV; ChAdOx1 MERS vaccines were produced with or without the leader sequence of the human tissue plasminogen activator gene (tPA) where MVA MERS vaccines were produced with tPA, but either the mH5 or F11 promoter driving expression of the spike gene. All vaccine candidates were evaluated in a mouse model in prime only or prime-boost regimens. ChAdOx1 MERS with tPA induced higher neutralising antibodies than ChAdOx1 MERS without tPA. A single dose of ChAdOx1 MERS with tPA elicited cellular immune responses as well as neutralising antibodies that were boosted to a significantly higher level by MVA MERS. The humoral immunogenicity of a single dose of ChAdOx1 MERS with tPA was equivalent to two doses of MVA MERS (also with tPA). MVA MERS with mH5 or F11 promoter induced similar antibody levels; however, F11 promoter enhanced the cellular immunogenicity of MVA MERS to significantly higher magnitudes. In conclusion, our study showed that MERS-CoV vaccine candidates could be optimized by utilising different viral vectors, various genetic designs of the vectors, or different regimens to increase immunogenicity. ChAdOx1 and MVA vectored vaccines have been safely evaluated in camels and humans and these MERS vaccine candidates should now be tested in camels and in clinical trials.

positive: Cross-Protection Induced by Encephalitis Vaccines against COVID-19 Might be a Reason for Relatively Lower Mortality Rate in Some Countries COronaVIrus Disease 2019 (COVID-19) is an on-going pandemic attributed to a novel virus named SARS‐CoV‐2. Comparing the statistics of incidence and death rates between nations reveals that there is discrepancy amongst countries in these regards, even between countries that share borders. We herein present information from the literature indicating how cross-protection against COVID-19 conferred by the encephalitis vaccine could be the reason for lower fatality rate in the countries where immunization against encephalitis is widespread or included in national programs. This may pave the way for arriving at efficient prevention strategies as well as vaccine development.

positive: Response of memory CD8+ T cells to severe acute respiratory syndrome (SARS) coronavirus in recovered SARS patients and healthy individuals. To date, the pathogenesis of severe acute respiratory syndrome (SARS) in humans is still not well understood. SARS coronavirus (SARS-CoV)-specific CTL responses, in particular their magnitude and duration of postinfection immunity, have not been extensively studied. In this study, we found that heat-inactivated SARS-CoV elicited recall CTL responses to newly identified spike protein-derived epitopes (SSp-1, S978, and S1202) in peripheral blood of all HLA-A*0201(+) recovered SARS patients over 1 year postinfection. Intriguingly, heat-inactivated SARS-CoV elicited recall-like CTL responses to SSp-1 but not to S978, S1202, or dominant epitopes from several other human viruses in 5 of 36 (13.8%) HLA-A*0201(+) healthy donors without any contact history with SARS-CoV. SSp-1-specific CTLs expanded from memory T cells of both recovered SARS patients, and the five exceptional healthy donors shared a differentiated effector CTL phenotype, CD45RA(+)CCR7(-)CD62L(-), and expressed CCR5 and CD44. However, compared with the high avidity of SSp-1-specific CTLs derived from memory T cells of recovered SARS patients, SSp-1-specific CTLs from the five exceptional healthy donors were of low avidity, as determined by their rapid tetramer dissociation kinetics and reduced cytotoxic reactivity, IFN-gamma secretion, and intracellular production of IFN-gamma, TNF-alpha, perforin, and granzyme A. These results indicate that SARS-CoV infection induces strong and long-lasting CTL-mediated immunity in surviving SARS patients, and that cross-reactive memory T cells to SARS-CoV may exist in the T cell repertoire of a small subset of healthy individuals and can be reactivated by SARS-CoV infection.

positive: A Comprehensive Literature Review on the Clinical Presentation, and Management of the Pandemic Coronavirus Disease 2019 (COVID-19) Coronavirus disease 2019 (COVID-19) is a declared global pandemic. There are multiple parameters of the clinical course and management of the COVID-19 that need optimization. A hindrance to this development is the vast amount of misinformation present due to scarcely sourced manuscript preprints and social media. This literature review aims to presents accredited and the most current studies pertaining to the basic sciences of SARS-CoV-2, clinical presentation and disease course of COVID-19, public health interventions, and current epidemiological developments. The review on basic sciences aims to clarify the jargon in virology, describe the virion structure of SARS-CoV-2 and present pertinent details relevant to clinical practice. Another component discussed is the brief history on the series of experiments used to explore the origins and evolution of the phylogeny of the viral genome of SARS-CoV-2. Additionally, the clinical and epidemiological differences between COVID-19 and other infections causing outbreaks (SARS, MERS, H1N1) are elucidated. Emphasis is placed on evidence-based medicine to evaluate the frequency of presentation of various symptoms to create a stratification system of the most important epidemiological risk factors for COVID-19. These can be used to triage and expedite risk assessment. Furthermore, the limitations and statistical strength of the diagnostic tools currently in clinical practice are evaluated. Criteria on rapid screening, discharge from hospital and discontinuation of self-quarantine are clarified. Epidemiological factors influencing the rapid rate of spread of the SARS-CoV-2 virus are described. Accurate information pertinent to improving prevention strategies is also discussed. The penultimate portion of the review aims to explain the involvement of micronutrients such as vitamin C and vitamin D in COVID19 treatment and prophylaxis. Furthermore, the biochemistry of the major candidates for novel therapies is briefly reviewed and a summary of their current status in the clinical trials is presented. Lastly, the current scientific data and status of governing bodies such as the Center of Disease Control (CDC) and the WHO on the usage of controversial therapies such as angiotensin-converting enzyme (ACE) inhibitors, nonsteroidal anti-inflammatory drugs (NSAIDs) (Ibuprofen), and corticosteroids usage in COVID-19 are discussed. The composite collection of accredited studies on each of these subtopics of COVID-19 within this review will enable clarification and focus on the current status and direction in the planning of the management of this global pandemic.

positive: Neutralizing antibodies mediate virus-immune pathology of COVID-19. SARS-CoV-2 is a novel beta-coronavirus causing over 200.000 lethal cases within six months of first infecting humans. SARS-CoV-2 causes COVID-19, a form of severe acute respiratory syndrome (SARS). COVID-19 is characterized by two phases: the first resembles the flu with pneumonia, but after about seven or eight days the disease suddenly worsens to a sepsis-like syndrome. It is difficult to explain this virus-immune-pathology sequence from virology or immunology only. This paper hypothesizes that host-produced anti-spike protein antibodies are responsible for immune-induced viral dissemination. Subsequently, systemic distribution of virus-antibodies complexes activates the immune pathology observed in severe COVID-19. This hypothesis may be counterintuitive to immunologist that consider many anti-spike antibodies to be virus-neutralizing antibodies. Although anti-spike antibodies may hinder infection of epithelial cells, antibody binding to the spike protein may facilitate virus infection of myeloid leukocytes. If myeloid leukocytes reenter the circulation, they could spread the virus from a locoregional infection to a systemic disease. Disseminated virus in combination with antibodies results in dispersed virus-antibody complexes that overstimulate the immune system. The hypothesis aligns with the sequences of virus, immune and pathological events in COVID-19. The delay in onset from both syndromes results from an immune system still naïve to the non-cross-reactive spike protein. Details of this hypothesis are in concordance with many clinical characteristics of COVID-19, including its predominant lethality for the elderly, and the mostly asymptomatic course of disease in children. It predicts putative detrimental effects of vaccines that induce virus-neutralizing antibodies against the spike protein, as has been shown for other coronaviruses. This hypothesis has consequences for treatment of patients, evaluation of personal and herd immunity and vaccine development. In patients, cellular immunity should be stimulated. Neutralizing antibodies might not be indicative for immunity. Vaccines should aim to stimulate cellular immunity COVID-19 and/or stimulate humoral immunity against viral proteins except for the immunodominant spike protein.

positive: The amount of cytokine-release defines different shades of Sars-Cov2 infection The recent outbreak of coronavirus disease (COVID 19), spreading from China all around the world in early 2020, has led scientists to investigate the immuno-mediated mechanisms underlying the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV2) infection. Depending on the amount of cytokines released as the result of the immunological activation induced by SARS-CoV2, three major clinical phenotypes can be identified: "mild",symbolized as a "drizzle" of cytokines, severe as a "storm", and critical as a "hurricane". In patients with mild symptoms, the release of pro-inflammatory cytokines is balanced to obtain a defense response against the virus which is often self-limiting and overcomes without tissue damage. In severe phenotype, resembling a "cytokine-release syndrome", SARS-CoV2 causes the lysis of the immune-mediators leading to a cytokine storm able to induce lung epithelium damage and acute respiratory distress syndrome. In critical patients, the immune response may become uncontrolled, thus the cytokine burst resembles a form of secondary hemophagocytic lymphohistiocytosis which may result in a multi organ failure. In addition to the standard of care, an immune-modulatory therapy tailored to each one of the different phenotypes should be used in order to prevent or reduce the release of cytokines responsible for organ damage and disease progression.

positive: Monoclonal antibodies for the S2 subunit of spike of SARS-CoV cross-react with the newly-emerged SARS-CoV-2 The emergence of a novel coronavirus, SARS-CoV-2, at the end of 2019 has resulted in widespread human infections across the globe. While genetically distinct from SARS-CoV, the etiological agent that caused an outbreak of severe acute respiratory syndrome (SARS) in 2003, both coronaviruses exhibit receptor binding domain (RBD) conservation and utilize the same host cell receptor, angiotensin-converting enzyme 2 (ACE2), for virus entry. Therefore, it will be important to test the cross-reactivity of antibodies that have been previously generated against the surface spike (S) glycoprotein of SARS-CoV in order to aid research on the newly emerged SARS-CoV-2. Here, we show that an immunogenic domain in the S2 subunit of SARS-CoV S is highly conserved in multiple strains of SARS-CoV-2. Consistently, four murine monoclonal antibodies (mAbs) raised against this immunogenic SARS-CoV fragment were able to recognise the S protein of SARS-CoV-2 expressed in a mammalian cell line. Importantly, one of them (mAb 1A9) was demonstrated to detect S in SARS-CoV-2-infected cells. To our knowledge, this is the first study showing that mAbs targeting the S2 domain of SARS-CoV can cross-react with SARS-CoV-2 and this observation is consistent with the high sequence conservation in the S2 subunit. These cross-reactive mAbs may serve as tools useful for SARS-CoV-2 research as well as for the development of diagnostic assays for its associated coronavirus disease COVID-19.

positive: Humoral and Cellular Immune Responses in Turkey Poults Infected with Turkey Coronavirus Abstract The objective of the present study was to elucidate the kinetics of humoral and cellular immune responses of turkey poults infected with turkey coronavirus (TCV). Turkey poults were orally inoculated with TCV at 10 d of age, and the immune responses were analyzed at 1, 3, 7, 14, 21, 28, 42, and 63 d postinfection (PI) in three different experiments. Total Ig to TCV was initially detected at 7 and 14 d PI in Experiments 1 and 3. In addition, Ig gradually increased from 7 to 21 d PI and remained at 80 immunofluroescent antibody assay (IFA) titers or more thereafter. Lymphocyte proliferation responses of spleen cells to concanavalin A were higher in TCV-infected turkeys than in noninfected control turkeys with significant differences (P < 0.05) being noted at 14 and 63 d PI in Experiment 2 and at 3 and 28 d PI in Experiment 3. Strong IFA staining response to TCV antigen was observed in intestines of turkeys at 1, 3, and 7 d PI, and the response declined from 14 to 28 d PI in Experiment 3. In Experiment 3, the IgG isotype antibody response to TCV was markedly increased after 21 d PI and remained high until 63 d PI. The IgM isotype antibody response to TCV was 1.40 and 0.91 at 7 and 14 d PI, respectively. The IgA isotype antibody response to TCV was very low as detected at 7 (0.13), 14 (0.20), and 21 (0.17) d PI. Turkeys infected with TCV had significantly higher (P < 0.05) antibody response to sheep erythrocytes than noninfected controls at 7 d PI. Virus-specific lymphocyte proliferation response of spleen cells was significantly stimulated (P < 0.05) at 63 d PI in Experiment 3. The proportion of the CD4+ subpopulation of T lymphocytes was significantly increased (P < 0.05) at 1, 7, and 21 d PI in Experiment 3. The results indicate that humoral and cellular immunities to TCV are elicited in turkeys following infection with TCV.

positive: Multiplex detection and dynamics of IgG antibodies to SARS-CoV2 and the highly pathogenic human Coronaviruses SARS-CoV and MERS-CoV BACKGROUND: Knowledge of the COVID-19 epidemic extent and the level of herd immunity is urgently needed to help manage this pandemic. METHODS: We used a panel of 167 samples (77 pre-epidemic and 90 COVID-19 seroconverters) and SARS-CoV1, SARS-CoV2 and MERS-CoV Spike and/or Nucleopcapsid (NC) proteins to develop a high throughput multiplex screening assay to detect IgG antibodies in human plasma. Assay performances were determined by ROC curves analysis. A subset of the COVID-19+ samples (n = 36) were also tested by a commercial NC-based ELISA test and the results compared with those of the novel assay. RESULTS: On samples collected ≥14 days after symptoms onset, the accuracy of the assay is 100% (95% CI: 100-100) for the Spike antigen and 99.9% (95% CI:99.7-100) for NC. By logistic regression, we estimated that 50% of the patients have seroconverted at 5.7 ± 1.6; 5.7 ± 1.8 and 7.9 ± 1.0 days after symptoms onset against Spike, NC or both antigens, respectively and all have seroconverted two weeks after symptoms onset. IgG titration in a subset of samples showed that early phase samples present lower IgG titers than those from later phase. IgG to SARS-CoV2 NC cross-reacted at 100% with SARS-CoV1 NC. Twenty-nine of the 36 (80.5%) samples tested were positive by the commercial ELISA while 31/36 (86.1%) were positive by the novel assay. CONCLUSIONS: Our assay is highly sensitive and specific for the detection of IgG antibodies to SARS-CoV2 proteins, suitable for high throughput epidemiological surveys. The novel assay is more sensitive than a commercial ELISA.

positive: Receptor-binding domain of MERS-CoV with optimal immunogen dosage and immunization interval protects human transgenic mice from MERS-CoV infection. Middle East respiratory syndrome (MERS) continues to raise worldwide concerns due to its pandemic potential. Increased MERS cases and no licensed MERS vaccines highlight the need to develop safe and effective vaccines against MERS. We have previously demonstrated that a receptor-binding domain (RBD) fragment containing residues 377-588 of MERS-coronavirus (MERS-CoV) spike protein is a critical neutralizing domain and an important vaccine target. Nevertheless, its optimal immunogen dosage and immunization interval, key factors for human-used vaccines that induce protective immunity, have never been investigated. In this study, we optimized these criteria using a recombinant MERS-CoV RBD protein fused with Fc (S377-588-Fc) and utilized the optimal immunization schedule to evaluate the protective efficacy of RBD against MERS-CoV infection in human dipeptidyl peptidase 4 transgenic (hDPP4-Tg) mice. Compared with one dose and 2 doses at 1-, 2-, and 3-week intervals, a regimen of 2 doses of this protein separated by an interval of 4 weeks induced the strongest antibody response and neutralizing antibodies against MERS-CoV infection, and maintained at a high level during the detection period. Notably, RBD protein at the optimal dosage and interval protected hDPP4-Tg mice against lethal MERS-CoV challenge, and the protection was positively correlated with serum neutralizing antibodies. Taken together, the optimal immunogen dosage and immunization interval identified in this study will provide useful guidelines for further development of MERS-CoV RBD-based vaccines for human use.

positive: Increased Immune Response Variability during Simultaneous Viral Coinfection Leads to Unpredictability in CD8 T Cell Immunity and Pathogenesis. UNLABELLED T cell memory is usually studied in the context of infection with a single pathogen in naive mice, but how memory develops during a coinfection with two pathogens, as frequently occurs in nature or after vaccination, is far less studied. Here, we questioned how the competition between immune responses to two viruses in the same naive host would influence the development of CD8 T cell memory and subsequent disease outcome upon challenge. Using two different models of coinfection, including the well-studied lymphocytic choriomeningitis (LCMV) and Pichinde (PICV) viruses, several differences were observed within the CD8 T cell responses to either virus. Compared to single-virus infection, coinfection resulted in substantial variation among mice in the size of epitope-specific T cell responses to each virus. Some mice had an overall reduced number of virus-specific cells to either one of the viruses, and other mice developed an immunodominant response to a normally subdominant, cross-reactive epitope (nucleoprotein residues 205 to 212, or NP205). These changes led to decreased protective immunity and enhanced pathology in some mice upon challenge with either of the original coinfecting viruses. In mice with PICV-dominant responses, during a high-dose challenge with LCMV clone 13, increased immunopathology was associated with a reduced number of LCMV-specific effector memory CD8 T cells. In mice with dominant cross-reactive memory responses, during challenge with PICV increased immunopathology was directly associated with these cross-reactive NP205-specific CD8 memory cells. In conclusion, the inherent competition between two simultaneous immune responses results in significant alterations in T cell immunity and subsequent disease outcome upon reexposure. IMPORTANCE Combination vaccines and simultaneous administration of vaccines are necessary to accommodate required immunizations and maintain vaccination rates. Antibody responses generally correlate with protection and vaccine efficacy. However, live attenuated vaccines also induce strong CD8 T cell responses, and the impact of these cells on subsequent immunity, whether beneficial or detrimental, has seldom been studied, in part due to the lack of known T cell epitopes to vaccine viruses. We questioned if the inherent increased competition and stochasticity between two immune responses during a simultaneous coinfection would significantly alter CD8 T cell memory in a mouse model where CD8 T cell epitopes are clearly defined. We show that some of the coinfected mice have sufficiently altered memory T cell responses that they have decreased protection and enhanced immunopathology when reexposed to one of the two viruses. These data suggest that a better understanding of human T cell responses to vaccines is needed to optimize immunization strategies.

positive: Middle East respiratory syndrome coronavirus vaccines: current status and novel approaches Middle East respiratory syndrome coronavirus (MERS-CoV) is a cause of severe respiratory infection in humans, specifically the elderly and people with comorbidities. The re-emergence of lethal coronaviruses calls for international collaboration to produce coronavirus vaccines, which are still lacking to date. Ongoing efforts to develop MERS-CoV vaccines should consider the different target populations (dromedary camels and humans) and the correlates of protection. Extending on our current knowledge of MERS, vaccination of dromedary camels to induce mucosal immunity could be a promising approach to diminish MERS-CoV transmission to humans. In addition, it is equally important to develop vaccines for humans that induce broader reactivity against various coronaviruses to be prepared for a potential next CoV outbreak.

positive: Antigenic Cross-Reactivity between Severe Acute Respiratory Syndrome—Associated Coronavirus and Human Coronaviruses 229E and OC43 Cross-reactivity between antibodies to different human coronaviruses (HCoVs) has not been systematically studied. By use of Western blot analysis, indirect immunofluorescence assay (IFA), and enzyme-linked immunosorbent assay (ELISA), antigenic cross-reactivity between severe acute respiratory syndrome (SARS)—associated coronavirus (SARS-CoV) and 2 HCoVs (229E and OC43) was demonstrated in immunized animals and human serum. In 5 of 11 and 10 of 11 patients with SARS, paired serum samples showed a ⩾4-fold increase in antibody titers against HCoV-229E and HCoV-OC43, respectively, by IFA. Overall, serum samples from convalescent patients who had SARS had a 1-way cross-reactivity with the 2 known HCoVs. Antigens of SARS-CoV and HCoV-OC43 were more cross-reactive than were those of SARS-CoV and HCoV-229E.

positive: High seroreactivity against SARS-CoV-2 Spike epitopes in a pre SARS-CoV-2 cohort: implications for antibody testing and vaccine design Little is known about the quality of polyclonal antibody responses in COVID-19 patients, and how it correlates with disease severity or patients' prior exposure to other pathogens. The whole polyclonal antibody repertoire in a retrospective cohort of 538 individuals was mapped against SARS-CoV-2 spike (S) glycoprotein, the main target of antibody immune responses in SARS-CoV-2 infection. Bioinformatic predictions identified 15 major B cell epitopes for S of SARS-CoV-2. Several epitopes localised in RBD of S including those spanning the ACE2-binding site, the highly conserved cryptic epitope of the neutralizing antibody of SARS-CoV, and fusion/entry domains of HR1 and HR2 of S protein of SARS-CoV-2. Intriguingly, some of these epitopes have cross-reactivity to antigens of common pathogens, potentially affecting SARS-CoV-2 infection outcome. High level of anti-Spike SARS-CoV-2 seroreactivity in populations with no history of exposure to SARS-CoV-2 is of clinical relevance and could underpin better understanding of COVID-19 pathophysiology in different populations and provide a blueprint for design of effective vaccines and developing better strategies for antibody testing.

positive: Long-term protection from SARS coronavirus infection conferred by a single immunization with an attenuated VSV-based vaccine Abstract Although the recent SARS coronavirus (SARS-CoV) that appeared in 2002 has now been contained, the possibility of re-emergence of SARS-CoV remains. Due to the threat of re-emergence, the overall fatality rate of ∼10%, and the rapid dispersion of the virus via international travel, viable vaccine candidates providing protection from SARS are clearly needed. We developed an attenuated VSV recombinant (VSV-S) expressing the SARS coronavirus (SARS-CoV) spike (S) protein. In cells infected with this recombinant, S protein was synthesized, glycosylated at approximately 17 Asn residues, and transported via the Golgi to the cell surface. Mice vaccinated with VSV-S developed SARS-neutralizing antibody and were able to control a challenge with SARS-CoV performed at 1 month or 4 months after a single vaccination. We also demonstrated, by passive antibody transfer, that the antibody response induced by the vaccine was sufficient for controlling SARS-CoV infection. A VSV-vectored SARS vaccine could have significant advantages over other SARS vaccine candidates described to date.

positive: Robust T cell immunity in convalescent individuals with asymptomatic or mild COVID-19 SARS-CoV-2-specific memory T cells will likely prove critical for long-term immune protection against COVID-19. We systematically mapped the functional and phenotypic landscape of SARS-CoV-2-specific T cell responses in a large cohort of unexposed individuals as well as exposed family members and individuals with acute or convalescent COVID-19. Acute phase SARS-CoV-2-specific T cells displayed a highly activated cytotoxic phenotype that correlated with various clinical markers of disease severity, whereas convalescent phase SARS-CoV-2-specific T cells were polyfunctional and displayed a stem-like memory phenotype. Importantly, SARS-CoV-2-specific T cells were detectable in antibody-seronegative family members and individuals with a history of asymptomatic or mild COVID-19. Our collective dataset shows that SARS-CoV-2 elicits robust memory T cell responses akin to those observed in the context of successful vaccines, suggesting that natural exposure or infection may prevent recurrent episodes of severe COVID-19 also in seronegative individuals.

positive: MERS-CoV vaccine candidates in development: The current landscape Middle East respiratory syndrome coronavirus (MERS-CoV), an emerging infectious disease of growing global importance, has caused severe acute respiratory disease in more than 1600 people, resulting in more than 600 deaths. The high case fatality rate, growing geographic distribution and vaguely defined epidemiology of MERS-CoV have created an urgent need for effective public health countermeasures, paramount of which is an effective means of prevention through a vaccine or antibody prophylaxis. Despite the relatively few number of cases to-date, research and development of MERS-CoV vaccine candidates is advancing quickly. This review surveys the landscape of these efforts across multiple groups in academia, government and industry.

positive: COVID‐19 is milder in children possibly due to cross immunity It has been unclear why the new severe acute respiratory syndrome coronavirus (sars‐CoV‐2) hits a small minority hard, while the vast majority of children appear to be protected and develop mild or no disease (1,2). The editorial by Brodin suggests some possible mechanisms why it is so (1). I would like to emphasize the significance of cross immunity due to previous exposure to seasonal coronavirus; it may be a plausible explanation for why children appear to be protected (2,3).

positive: Immune responses in COVID-19 and potential vaccines: Lessons learned from SARS and MERS epidemic. As the world is witnessing the epidemic of COVID-19, a disease caused by a novel coronavirus, SARS-CoV-2, emerging genetics and clinical evidences suggest a similar path to those of SARS and MERS. The rapid genomic sequencing and open access data, together with advanced vaccine technology, are expected to give us more knowledge on the pathogen itself, including the host immune response as well as the plan for therapeutic vaccines in the near future. This review aims to provide a comparative view among SARS-CoV, MERS-CoV and the newly epidemic SARS-CoV-2, in the hope to gain a better understanding of the host-pathogen interaction, host immune responses, and the pathogen immune evasion strategies. This predictive view may help in designing an immune intervention or preventive vaccine for COVID-19 in the near future.

positive: T-cell immunity of SARS-CoV: Implications for vaccine development against MERS-CoV Abstract Over 12 years have elapsed since severe acute respiratory syndrome (SARS) triggered the first global alert for coronavirus infections. Virus transmission in humans was quickly halted by public health measures and human infections of SARS coronavirus (SARS-CoV) have not been observed since. However, other coronaviruses still pose a continuous threat to human health, as exemplified by the recent emergence of Middle East respiratory syndrome (MERS) in humans. The work on SARS-CoV widens our knowledge on the epidemiology, pathophysiology and immunology of coronaviruses and may shed light on MERS coronavirus (MERS-CoV). It has been confirmed that T-cell immunity plays an important role in recovery from SARS-CoV infection. Herein, we summarize T-cell immunological studies of SARS-CoV and discuss the potential cross-reactivity of the SARS-CoV-specific immunity against MERS-CoV, which may provide useful recommendations for the development of broad-spectrum vaccines against coronavirus infections.

positive: Molecular immune pathogenesis and diagnosis of COVID-19 Coronavirus disease 2019 (COVID-19) is a kind of viral pneumonia which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The emergence of SARS-CoV-2 has been marked as the third introduction of a highly pathogenic coronavirus into the human population after the severe acute respiratory syndrome coronavirus (SARS-CoV) and the Middle East respiratory syndrome coronavirus (MERS-CoV) in the twenty-first century. In this minireview, we provide a brief introduction of the general features of SARS-CoV-2 and discuss current knowledge of molecular immune pathogenesis, diagnosis and treatment of COVID-19 on the base of the present understanding of SARS-CoV and MERS-CoV infections, which may be helpful in offering novel insights and potential therapeutic targets for combating the SARS-CoV-2 infection.

positive: The recombinant N-terminal domain of spike proteins is a potential vaccine against Middle East respiratory syndrome coronavirus (MERS-CoV) infection Abstract The persistent public health threat of infection with the Middle East respiratory syndrome coronavirus (MERS-CoV) highlights the need for an effective MERS-CoV vaccine. Previous studies have focused mainly on the receptor-binding domain (RBD) on the spike protein of MERS-CoV. Herein, we investigated the immunogenicity and protective potential of the recombinant N-terminal domain (rNTD) of spike proteins as a vaccine candidate. BALB/c mice vaccinated with 5 or 10μg of rNTD protein demonstrated a significant humoral immune response (serum IgG and neutralizing activity). Additionally, according to the enzyme-linked immunospot, intracellular cytokine staining, and cytometric bead array assays, significant and functional T-cell immunity was induced by 10μg of the rNTD vaccination with aluminum and CpG adjuvant. Furthermore, rNTD-immunized mice showed reduced lung abnormalities in a MERS-CoV-challenge mouse model transfected with an adenoviral vector expressing human DPP4, showing protection consistent with that found with rRBD vaccination. These data show that rNTD induced potent cellular immunity and antigen-specific neutralizing antibodies in mice and that it demonstrated protective capacity against a viral challenge, indicating that rNTD is a vaccine candidate against MERS-CoV infection.

positive: Evaluation of Serologic and Antigenic Relationships Between Middle Eastern Respiratory Syndrome Coronavirus and Other Coronaviruses to Develop Vaccine Platforms for the Rapid Response to Emerging Coronaviruses Background. Middle East respiratory syndrome coronavirus (MERS-CoV) emerged in 2012, causing severe acute respiratory disease and pneumonia, with 44% mortality among 136 cases to date. Design of vaccines to limit the virus spread or diagnostic tests to track newly emerging strains requires knowledge of antigenic and serologic relationships between MERS-CoV and other CoVs. Methods. Using synthetic genomics and Venezuelan equine encephalitis virus replicons (VRPs) expressing spike and nucleocapsid proteins from MERS-CoV and other human and bat CoVs, we characterize the antigenic responses (using Western blot and enzyme-linked immunosorbent assay) and serologic responses (using neutralization assays) against 2 MERS-CoV isolates in comparison with those of other human and bat CoVs. Results. Serologic and neutralization responses against the spike glycoprotein were primarily strain specific, with a very low level of cross-reactivity within or across subgroups. CoV N proteins within but not across subgroups share cross-reactive epitopes with MERS-CoV isolates. Our findings were validated using a convalescent-phase serum specimen from a patient infected with MERS-CoV (NA 01) and human antiserum against SARS-CoV, human CoV NL63, and human CoV OC43. Conclusions. Vaccine design for emerging CoVs should involve chimeric spike protein containing neutralizing epitopes from multiple virus strains across subgroups to reduce immune pathology, and a diagnostic platform should include a panel of nucleocapsid and spike proteins from phylogenetically distinct CoVs.

positive: Human memory T cell responses to SARS-CoV E protein Abstract E protein is a membrane component of severe acute respiratory syndrome coronavirus (SARS-CoV). Disruption of E protein may reduce viral infectivity. Thus, the SARS-CoV E protein is considered a potential target for the development of antiviral drugs. However, the cellular immune responses to E protein remain unclear in humans. In this study, we found that peripheral blood mononuclear cells (PBMCs) from fully recovered SARS individuals rapidly produced IFN-γ and IL-2 following stimulation with a pool of 9 peptides overlapping the entire E protein sequence. Analysis of the immune responses by flow cytometry showed that both CD4+ and CD8+T cells were involved in the SARS-CoV E-specific immune responses after stimulation with SARS-CoV E peptides. Moreover, the majority of IFN-γ+CD4+T cells were central memory cells expressing CD45RO+CCR7+CD62L−; whereas IFN-γ+CD8+ memory T cells were mostly effector memory cells expressing CD45RO−CCR7−CD62L−. The results of T-cell responses to 9 individual peptides indicated that the E protein contained at least two major T cell epitopes (E2 amino acid [aa] 9–26 and E5–6: aa 33–57) which were important in eliciting cellular immune response to SARS-CoV E protein in humans.

positive: Antibodies to SARS-CoV-2 and their potential for therapeutic passive immunization We review aspects of the antibody response to SARS-CoV-2, the causative agent of the COVID-19 pandemic. The topics we cover are relevant to immunotherapy with plasma from recovered patients, monoclonal antibodies against the viral S-protein, and soluble forms of the receptor for the virus, angiotensin converting enzyme 2. The development of vaccines against SARS-CoV-2, an essential public health tool, will also be informed by an understanding of the antibody response in infected patients. Although virus-neutralizing antibodies are likely to protect, antibodies could potentially trigger immunopathogenic events in SARS-CoV-2-infected patients or enhance infection. An awareness of these possibilities may benefit clinicians and the developers of antibody-based therapies and vaccines.

positive: Explore the Possible Impact of BCG Vaccination Policy on the Morbidity, Mortality, and Recovery Rates due to COVID-19 Infection. BACKGROUND The Coronavirus Disease-19 (COVID-19) is the new form of an acute infectious respiratory disease and has quickly spread over most continents in the world. Recently, it has been shown that Bacille Calmette-Guerin (BCG) might protect against COVID-19. This study aims to investigate the possible correlation between BCG vaccination and morbidity/mortality/recovery rate associated with COVID-19 infection. METHODS Data of COVID-19 confirmed cases, deaths, recoveries, and population were obtained from https://www.worldometers.info/coronavirus/ (Accessed on 12 June, 2020). To have meaningful comparisons among countries' mortality and recovery rates, we only choose those countries with COVID-19 infected cases at least 200. The Poisson regression and logistic regression were used to explore the relationship between BCG vaccination and morbidity, mortality and recovery rates. RESULTS Among those 158 countries with at least 200 COVID-19 infected cases, there were 141 countries with BCG vaccination information available. The adjusted rates ratio of COVID-19 confirmed cases for Current BCG vaccination vs. non-Current BCG vaccination was 0.339 (with 95% CI= (0.338,0.340)). Moreover, the adjusted odds ratio (OR) of death and recovery after coronavirus infected for Current BCG vaccination vs. non-Current BCG vaccination were 0.258 (with 95% CI= (0.254,0.261)) and 2.151 (with 95% CI= (2.140,2.163)), respectively. CONCLUSIONS That data in this study show the BCG might provide the protection against COVID-19, with consequent less COVID-19 infection and deaths and more rapid recovery. BCG vaccine might bridge the gap before the disease-specific vaccine is developed, but this hypothesis needs to be further tested in rigorous randomized clinical trials.

positive: COVID-19 Vaccine Candidates: Prediction and Validation of 174 SARS-CoV-2 Epitopes The recent outbreak of SARS-CoV-2 (2019-nCoV) virus has highlighted the need for fast and efficacious vaccine development. Stimulation of a proper immune response that leads to protection is highly dependent on presentation of epitopes to circulating T-cells via the HLA complex. SARS-CoV-2 is a large RNA virus and testing of all overlapping peptides in vitro to deconvolute an immune response is not feasible. Therefore HLA-binding prediction tools are often used to narrow down the number of peptides to test. We tested 19 epitope-HLA-binding prediction tools, and using an in vitro peptide MHC stability assay, we assessed 777 peptides that were predicted to be good binders across 11 MHC allotypes. In this investigation of potential SARS-CoV-2 epitopes we found that current prediction tools vary in performance when assessing binding stability, and they are highly dependent on the MHC allotype in question. Designing a COVID-19 vaccine where only a few epitope targets are included is therefore a very challenging task. Here, we present 174 SARS-CoV-2 epitopes with high prediction binding scores, validated to bind stably to 11 HLA allotypes. Our findings may contribute to the design of an efficacious vaccine against COVID-19.

positive: Targets of T Cell Responses to SARS-CoV-2 Coronavirus in Humans with COVID-19 Disease and Unexposed Individuals Understanding adaptive immunity to SARS-CoV-2 is important for vaccine development, interpreting coronavirus disease 2019 (COVID-19) pathogenesis, and calibration of pandemic control measures. Using HLA class I and II predicted peptide "megapools," circulating SARS-CoV-2-specific CD8+ and CD4+ T cells were identified in â¼70% and 100% of COVID-19 convalescent patients, respectively. CD4+ T cell responses to spike, the main target of most vaccine efforts, were robust and correlated with the magnitude of the anti-SARS-CoV-2 IgG and IgA titers. The M, spike, and N proteins each accounted for 11%-27% of the total CD4+ response, with additional responses commonly targeting nsp3, nsp4, ORF3a, and ORF8, among others. For CD8+ T cells, spike and M were recognized, with at least eight SARS-CoV-2 ORFs targeted. Importantly, we detected SARS-CoV-2-reactive CD4+ T cells in â¼40%-60% of unexposed individuals, suggesting cross-reactive T cell recognition between circulating "common cold" coronaviruses and SARS-CoV-2.

positive: Single-dose replicating RNA vaccine induces neutralizing antibodies against SARS-CoV-2 in nonhuman primates The ongoing COVID-19 pandemic, caused by infection with SARS-CoV-2, is having a dramatic and deleterious impact on health services and the global economy. Grim public health statistics highlight the need for vaccines that can rapidly confer protection after a single dose and be manufactured using components suitable for scale-up and efficient distribution. In response, we have rapidly developed repRNA-CoV2S, a stable and highly immunogenic vaccine candidate comprised of an RNA replicon formulated with a novel Lipid InOrganic Nanoparticle (LION) designed to enhance vaccine stability, delivery and immunogenicity. We show that intramuscular injection of LION/repRNA-CoV2S elicits robust anti-SARS-CoV-2 spike protein IgG antibody isotypes indicative of a Type 1 T helper response as well as potent T cell responses in mice. Importantly, a single-dose administration in nonhuman primates elicited antibody responses that potently neutralized SARS-CoV-2. These data support further development of LION/repRNA-CoV2S as a vaccine candidate for prophylactic protection from SARS-CoV-2 infection.

positive: Long-term coexistence of SARS-CoV-2 with antibody response in COVID-19 patients Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection causing coronavirus disease 2019 (COVID-19) has spread worldwide. Whether antibodies are important for the adaptive immune responses against SARS-CoV-2 infection needs to be determined. Here, 26 cases of COVID-19 in Jinan, China, were examined and shown to be mild or with common clinical symptoms, and no case of severe symptoms was found among these patients. Strikingly, a subset of these patients had SARS-CoV-2 and virus-specific IgG coexist for an unexpectedly long time, with two cases for up to 50 days. One COVID-19 patient who did not produce any SARS-CoV-2-bound IgG successfully cleared SARS-CoV-2 after 46 days of illness, revealing that without antibody-mediated adaptive immunity, innate immunity alone may still be powerful enough to eliminate SARS-CoV-2. This report may provide a basis for further analysis of both innate and adaptive immunity in SARS-CoV-2 clearance, especially in nonsevere cases.

positive: Two X‐linked agammaglobulinemia patients develop pneumonia as COVID‐19 manifestation but recover BACKGROUND: The recent SARS‐CoV‐2 pandemic, which has recently affected Italy since February 21, constitutes a threat to normal subjects, as the coronavirus disease‐19 (COVID‐19) can manifest with a broad spectrum of clinical phenotypes ranging from asymptomatic cases to pneumonia or even death. There is evidence that older age and several comorbidities can affect the risk to develop severe pneumonia and possibly the need of mechanic ventilation in subjects infected with SARS‐CoV‐2. Therefore, we evaluated the outcome of SARS‐CoV‐2 infection in patients with inborn errors of immunity (IEI) such as X‐linked agammaglobulinemia (XLA). METHODS: When the SARS‐CoV‐2 epidemic has reached Italy, we have activated a surveillance protocol of patients with IEI, to perform SARS‐CoV‐2 search by nasopharyngeal swab in patients presenting with symptoms that could be a manifestation of COVID‐19, such as fever, cough, diarrhea, or vomiting. RESULTS: We describe two patients with X‐linked agammaglobulinemia (XLA) aged 34 and 26 years with complete absence of B cells from peripheral blood who developed COVID‐19, as diagnosed by SARS‐CoV‐2 detection by nasopharyngeal swab, while receiving immunoglobulin infusions. Both patients developed interstitial pneumonia characterized by fever, cough, and anorexia and associated with elevation of CRP and ferritin, but have never required oxygen ventilation or intensive care. CONCLUSION: Our report suggests that XLA patients might present with high risk to develop pneumonia after SARS‐CoV‐2 infection, but can recover from infection, suggesting that B‐cell response might be important, but is not strictly required to overcome the disease. However, there is a need for larger observational studies to extend these conclusions to other patients with similar genetic immune defects.

positive: Therapeutic Targeting of RIG-I and MDA5 Might Not Lead to the Same Rome RIG-I and MDA5 receptors are key sensors of pathogen-associated molecular pattern (PAMP)-containing viral RNA and transduce downstream signals to activate an antiviral and immunomodulatory response. Fifteen years of research have put them at the center of an ongoing hunt for novel pharmacological pan-antivirals, vaccine adjuvants, and antitumor strategies. Current knowledge testifies to the redundant, but also distinct, functions mediated by RIG-I and MDA5, opening opportunities for the use of specific and potent nucleic acid agonists. We critically discuss the evidence and remaining knowledge gaps that have an impact on the choice and design of optimal RNA ligands to achieve an appropriate immunostimulatory response, with limited adverse effects, for prophylactic and therapeutic interventions against viruses and cancer in humans.

positive: The paramount importance of serological surveys of SARS-CoV-2 infection and immunity

positive: A perspective on potential antibody-dependent enhancement of SARS-CoV-2. The possibility of antibody-dependent enhancement (ADE) of disease is a general concern for the development of vaccines and antibody therapies because the mechanisms that underlie antibody protection have the theoretical potential to amplify viral infections or trigger immunopathology. Observations relevant to the risks of ADE of disease require careful review at this critical point in the SARS-CoV-2 pandemic. At present, no clinical findings, immunologic assays or biomarkers are known to differentiate any severe viral infection from immune-enhanced disease, whether by antibodies, T cells or intrinsic host responses. In vitro systems and animal models do not predict the risk of ADE of disease, in part because protective and potentially detrimental antibody-mediated mechanisms are the same, and designing animal models depends on understanding how antiviral host responses may become harmful in people. The implications of our lack of knowledge are twofold. First, comprehensive studies are urgently needed to define clinical correlates of protective immunity against SARS-CoV-2. Second, since we cannot predict ADE of disease reliably after either vaccination or treatment with antibodies, regardless of what virus is the causative agent, it will be essential to depend on careful analysis of safety in humans as immune interventions for COVID-19 disease move forward.

positive: CD8+ T cell cross-reactivity against SARS-CoV-2 conferred by other coronavirus strains and influenza virus While individuals infected with coronavirus disease 2019 (COVID-19) manifested a broad range in susceptibility and severity to the disease, the pre-existing immune memory of related pathogens can influence the disease outcome. Here, we investigated the potential extent of T cell cross-reactivity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that can be conferred by other coronaviruses and influenza virus, and generated a map of public and private predicted CD8+ T cell epitopes between coronaviruses. Moreover, to assess the potential risk of self-reactivity and/or diminished T cell response for peptides identical or highly similar to the host, we identified predicted epitopes with high sequence similarity with human proteome. Lastly, we compared predicted epitopes from coronaviruses with epitopes from influenza virus deposited in IEDB to support vaccine development against different virus strains. We believe the comprehensive in silico profile of private and public predicted epitopes across coronaviruses and influenza viruses will facilitate design of vaccines capable of protecting against various viral infections.

positive: Immunity and protection from COVID‐19—Environmental mycobacteria play a role Kerboua et al1 discussed about the immunity induced by nonspecific inflammation and BCG (Bacillus Calmette-Guerin) as factors altering the susceptibility to severe illness from coronavirus disease 2019 (COVID-19). Ozdemir et al2 in their study have shown proportionately less number of cases, milder illness and a lower death rate in BCG vaccinated population as compared to BCG non-vaccinated across different countries and hemispheres.2 This article is protected by copyright. All rights reserved.

positive: Substantial undocumented infection facilitates the rapid dissemination of novel coronavirus (SARS-CoV2) Estimation of the prevalence and contagiousness of undocumented novel coronavirus (SARS-CoV2) infections is critical for understanding the overall prevalence and pandemic potential of this disease. Here we use observations of reported infection within China, in conjunction with mobility data, a networked dynamic metapopulation model and Bayesian inference, to infer critical epidemiological characteristics associated with SARS-CoV2, including the fraction of undocumented infections and their contagiousness. We estimate 86% of all infections were undocumented (95% CI: [82%–90%]) prior to 23 January 2020 travel restrictions. Per person, the transmission rate of undocumented infections was 55% of documented infections ([46%–62%]), yet, due to their greater numbers, undocumented infections were the infection source for 79% of documented cases. These findings explain the rapid geographic spread of SARS-CoV2 and indicate containment of this virus will be particularly challenging.

positive: Lack of peripheral memory B cell responses in recovered patients with severe acute respiratory syndrome: a six-year follow-up study. Six years have passed since the outbreak of severe acute respiratory syndrome (SARS). Previous studies indicated that specific Abs to SARS-related coronavirus (SARS-CoV) waned over time in recovered SARS patients. It is critical to find out whether a potential anamnestic response, as seen with other viral infections, exists to protect a person from reinfection in case of another SARS outbreak. Recovered SARS patients were followed up to 6 y to estimate the longevity of specific Ab. The specific memory B cell and T cell responses to SARS-CoV Ags were measured by means of ELISPOT assay. Factors in relation to humoral and cellular immunity were investigated. Six years postinfection, specific IgG Ab to SARS-CoV became undetectable in 21 of the 23 former patients. No SARS-CoV Ag-specific memory B cell response was detected in either 23 former SARS patients or 22 close contacts of SARS patients. Memory T cell responses to a pool of SARS-CoV S peptides were identified in 14 of 23 (60.9%) recovered SARS patients, whereas there was no such specific response in either close contacts or healthy controls. Patients with more severe clinical manifestations seemed to present a higher level of Ag-specific memory T cell response. SARS-specific IgG Ab may eventually vanish and peripheral memory B cell responses are undetectable in recovered SARS patients. In contrast, specific T cell anamnestic responses can be maintained for at least 6 y. These findings have applications in preparation for the possible reemergence of SARS.

positive: SARS-CoV-2 will constantly sweep its tracks: a vaccine containing CpG motifs in ‘lasso’ for the multi-faced virus During the current COVID-19 pandemic, the global ratio between the dead and the survivors is approximately 1 to 10, which has put humanity on high alert and provided strong motivation for the intensive search for vaccines and drugs. It is already clear that if we follow the most likely scenario, which is similar to that used to create seasonal influenza vaccines, then we will need to develop improved vaccine formulas every year to control the spread of the new, highly mutable coronavirus SARS-CoV-2. In this article, using well-known RNA viruses (HIV, influenza viruses, HCV) as examples, we consider the main successes and failures in creating primarily highly effective vaccines. The experience accumulated dealing with the biology of zoonotic RNA viruses suggests that the fight against COVID-19 will be difficult and lengthy. The most effective vaccines against SARS-CoV-2 will be those able to form highly effective memory cells for both humoral (memory B cells) and cellular (cross-reactive antiviral memory T cells) immunity. Unfortunately, RNA viruses constantly sweep their tracks and perhaps one of the most promising solutions in the fight against the COVID-19 pandemic is the creation of 'universal' vaccines based on conservative SARS-CoV-2 genome sequences (antigen-presenting) and unmethylated CpG dinucleotides (adjuvant) in the composition of the phosphorothioate backbone of single-stranded DNA oligonucleotides (ODN), which can be effective for long periods of use. Here, we propose a SARS-CoV-2 vaccine based on a lasso-like phosphorothioate oligonucleotide construction containing CpG motifs and the antigen-presenting unique ACG-containing genome sequence of SARS-CoV-2. We found that CpG dinucleotides are the least rare dinucleotides in the genomes of SARS-CoV-2 and other known human coronaviruses, and hypothesized that their higher frequency could be responsible for the unwanted increased lethality to the host, causing a ‘cytokine storm’ in people who overexpress cytokines through the activation of specific Toll-like receptors in a manner similar to TLR9-CpG ODN interactions. Interestingly, the virus strains sequenced in China (Wuhan) in February 2020 contained on average one CpG dinucleotide more in their genome than the later strains from the USA (New York) sequenced in May 2020. Obviously, during the first steps of the microevolution of SARS-CoV-2 in the human population, natural selection tends to select viral genomes containing fewer CpG motifs that do not trigger a strong innate immune response, so the infected person has moderate symptoms and spreads SARS-CoV-2 more readily. However, in our opinion, unmethylated CpG dinucleotides are also capable of preparing the host immune system for the coronavirus infection and should be present in SARS-CoV-2 vaccines as strong adjuvants.

positive: Neutralizing antibodies mediate virus-immune pathology of COVID-19 SARS-CoV-2 is a novel beta-coronavirus causing over 200.000 lethal cases within six months of first infecting humans. SARS-CoV-2 causes COVID-19, a form of severe acute respiratory syndrome (SARS). COVID-19 is characterized by two phases: the first resembles the flu with pneumonia, but after about seven or eight days the disease suddenly worsens to a sepsis-like syndrome. It is difficult to explain this virus-immune-pathology sequence from virology or immunology only. This paper hypothesizes that host-produced anti-spike protein antibodies are responsible for immune-induced viral dissemination. Subsequently, systemic distribution of virus-antibodies complexes activates the immune pathology observed in severe COVID-19. This hypothesis may be counterintuitive to immunologist that consider many anti-spike antibodies to be virus-neutralizing antibodies. Although anti-spike antibodies may hinder infection of epithelial cells, antibody binding to the spike protein may facilitate virus infection of myeloid leukocytes. If myeloid leukocytes reenter the circulation, they could spread the virus from a locoregional infection to a systemic disease. Disseminated virus in combination with antibodies results in dispersed virus-antibody complexes that overstimulate the immune system. The hypothesis aligns with the sequences of virus, immune and pathological events in COVID-19. The delay in onset from both syndromes results from an immune system still naïve to the non-cross-reactive spike protein. Details of this hypothesis are in concordance with many clinical characteristics of COVID-19, including its predominant lethality for the elderly, and the mostly asymptomatic course of disease in children. It predicts putative detrimental effects of vaccines that induce virus-neutralizing antibodies against the spike protein, as has been shown for other coronaviruses. This hypothesis has consequences for treatment of patients, evaluation of personal and herd immunity and vaccine development. In patients, cellular immunity should be stimulated. Neutralizing antibodies might not be indicative for immunity. Vaccines should aim to stimulate cellular immunity COVID-19 and/or stimulate humoral immunity against viral proteins except for the immunodominant spike protein.

positive: The production of antibodies for SARS-CoV-2 and its clinical implication Background: Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2), a novel betacoronavirus, has caused an outburst of pneumonia cases in Wuhan, China. We report the production of specific IgM and IgG antibodies after the infection of SARS-CoV-2 and its implication for the diagnosis, pathology and the course of the disease as well as the recurrence of positive nucleic acid tests after discharge. Methods: Test results for SARS-CoV-2 IgM and IgG antibodies of 221 confirmed COVID-19 patients were retrospectively examined, and their clinical data were collected and analyzed based on various subgroups. SARS-CoV-2 IgM and IgG antibodies were determined with the chemiluminescence method. Findings: The concentration (S/CO) of SARS-CoV-2 IgM and IgG antibodies peaked on day 19-21 after symptom onset, with a median of 17.38 (IQR 4.39-36.4) for IgM and 5.59 (IQR 0.73-13.65) for IgG. Detection rates reached highest on day 16-18 and day 19-21 for IgM and IgG, which were 73.6% and 98.6%, respectively, with significantly higher concentration of IgG in critically ill patients than in those with mild to moderate disease (P=0.027). The concentration of the antibodies on day 16-21 is not correlated with the course or outcome of the disease (Spearman r < 0.20, P > 0.05). Nasopharyngeal swabs revealed positive SARS-CoV-2 RNA in up to 52.7% of recovered patients after discharge, whose IgG proved to be significantly lower than that of those with negative RNA results (P = 0.009). IgG and IgM were tested twice within 14 days after discharge with a 7-day interval, and the second testing of these antibodies displayed a decrease in concentration of 21.2% (IQR, 11.2%34.48%) for IgG and 23.05% (IQR, -27.96%46.13%) for IgM, without statistical significance between the patients with re-detectable positive RNA results and those with negative RNA results after discharge. However, those with positive results experienced a count decrease in lymphocyte subsets. Interpretation: The concentration of SARS-CoV-2 IgM and IgG antibodies peaked on day 19-21 after symptom onset, and antibody testing on day 16-21 is associated with increased detection rates, but the antibody concentration does not affect the course and outcome of the infection. Recovering patients with re-detectable positive SARS-CoV-2 RNA displayed lower concentration of IgG, but the downward trend of IgG during recovery indicated its limited duration of protection, and the protective effect of IgG remains to be investigated.

positive: Immune responses against SARS-coronavirus nucleocapsid protein induced by DNA vaccine Abstract The nucleocapsid (N) protein of SARS-coronavirus (SARS-CoV) is the key protein for the formation of the helical nucleocapsid during virion assembly. This protein is believed to be more conserved than other proteins of the virus, such as spike and membrane glycoprotein. In this study, the N protein of SARS-CoV was expressed in Escherichia coli DH5α and identified with pooled sera from patients in the convalescence phase of SARS. A plasmid pCI-N, encoding the full-length N gene of SARS-CoV, was constructed. Expression of the N protein was observed in COS1 cells following transfection with pCI-N. The immune responses induced by intramuscular immunization with pCI-N were evaluated in a murine model. Serum anti-N immunoglobulins and splenocytes proliferative responses against N protein were observed in immunized BALB/c mice. The major immunoglobulin G subclass recognizing N protein was immunoglobulin G2a, and stimulated splenocytes secreted high levels of gamma interferon and IL-2 in response to N protein. More importantly, the immunized mice produced strong delayed-type hypersensitivity (DTH) and CD8+ CTL responses to N protein. The study shows that N protein of SARS-CoV not only is an important B cell immunogen, but also can elicit broad-based cellular immune responses. The results indicate that the N protein may be of potential value in vaccine development for specific prophylaxis and treatment against SARS.

positive: In silico approach for designing of a multi-epitope based vaccine against novel Coronavirus (SARS-COV-2) A novel Coronavirus (SARS-COV-2) has now become a global pandemic. Considering the severity of infection and the associated mortalities, there is an urgent need to develop an effective preventive measure against this virus. In this study, we have designed a novel vaccine construct using computational strategies. Spike (S) glycoprotein is the major antigenic component that trigger the host immune responses. Detailed investigation of S protein with various immunoinformatics tools enabled us to identify 5 MHC I and 5 MHC II B-cell derived T-cell epitopes with VaxiJen score > 1 and IC50 value < 100nM. These epitopes were joined with a suitable adjuvant and appropriate linkers to form a multi-epitope based vaccine construct. Further, in silico testing of the vaccine construct for its antigenicity, allergenicity, solubility, and other physicochemical properties showed it to be safe and immunogenic. Suitable tertiary structure of the vaccine protein was generated using 3Dpro of SCRATCH suite, refined with GalaxyRefine, and validated with ProSA, PROCHECK, and ERRAT server. Finally, molecular docking studies were performed to ensure a favorable binding affinity between the vaccine construct and TLR3 receptor. The designed multi-epitope vaccine showed potential to elicit specific immune responses against the SARS-COV-2. However, further wet lab validation is necessary to confirm the actual effectiveness, safety and immunogenic potency of the vaccine construct against derived in this study.

positive: Protective effects of vaccinations and endemic infections on COVID-19: A Hypothesis

positive: Comparing the binding interactions in the receptor binding domains of SARS-CoV-2 and SARS-CoV COVID-19, since emerged in Wuhan, China, has been a major concern due to its high infection rate, leaving more than one million infected people around the world. Huge number of studies tried to reveal the structure of the SARS-CoV-2 compared to the SARS-CoV-1, in order to suppress this high infection rate. Some of these studies showed that the mutations in the SARS-CoV-1 Spike protein might be responsible for its higher affinity to the ACE2 human cell receptor. In this work, we used molecular dynamics simulations and Monte Carlo sampling to compare the binding affinities of the spike proteins of SARS-CoV and SARS-CoV-2 to the ACE2. We found that the SARS-CoV-2 binds to ACE2 stronger than SARS-CoV by 7 kcal/mol, due to enhanced electrostatic interactions. The major contributions to the electrostatic binding energies are resulting from the salt-bridges formed between R426 and ACE2-E329 in case of SARS-CoV and K417 and ACE2-D30 for SARS-CoV2. In addition, there is no significant contribution from a single mutant to the binding energies. However, these mutations induce sophisticated structural changes that enhance the binding energies. Our results also indicate that the SARS-CoV-2 is unlikely a lab engineered virus.

positive: Th2 predominance and CD8+ memory T cell depletion in patients with severe acute respiratory syndrome Abstract The immune spectrum of severe acute respiratory syndrome (SARS) is poorly understood. To define the dynamics of the immune spectrum in SARS, serum levels of cytokines, chemokines, immunoglobulins, complement and specific antibodies against SARS-associated coronavirus (SARS-CoV) were assayed by enzyme-linked immunosorbent assay (ELISA), and phenotypes of peripheral lymphocytes were analyzed by flow cytometry in 95 SARS-infected patients. Results showed that interleukin (IL)-10 and transforming growth factor β (TGF-β) were continuously up-regulated during the entirety of SARS. Regulated on activation normally T cell-expressed and secreted (RANTES) levels were decreased, while monocyte chemoattractant protein-1 (MCP-1) was elevated in acute patients. Immunoglobulins and complement were elevated during the first month of SARS. Both serum-positive rates and titers of specific IgM and IgG antibodies responding to SARS-CoV peaked at days 41–60 from the onset of SARS. CD4+ and CD8+ T lymphocytes decreased significantly in acute-phase. CD3+CD8+CD45RO+ T lymphocytes were decreased by 36.78% in the convalescent patients. Conclusion: SARS-CoV seemed to elicit effective humoral immunity but inhibited cellular immunity, especially CD8+ memory T lymphocytes over time. Prolonged overproduction of IL-10 and TGF-β may play an important role in the disease.

positive: Is it fair to hope that patients with Type 1 Diabetes (autoimmune) may be spared by the infection of Covid-19? The CoV-19 infection appears to be unusual among patients with type 1Diabetes Mellitus, although they are considered a fragile population. We think that this in part due to the peculiar immune condition that leads to the destruction of the Beta cells.

positive: The epidemiology and pathogenesis of coronavirus disease (COVID-19) outbreak Abstract Coronavirus disease (COVID-19) is caused by SARS-COV2 and represents the causative agent of a potentially fatal disease that is of great global public health concern. Based on the large number of infected people that were exposed to the wet animal market in Wuhan City, China, it is suggested that this is likely the zoonotic origin of COVID-19. Person-to-person transmission of COVID-19 infection led to the isolation of patients that were subsequently administered a variety of treatments. Extensive measures to reduce person-to-person transmission of COVID-19 have been implemented to control the current outbreak. Special attention and efforts to protect or reduce transmission should be applied in susceptible populations including children, health care providers, and elderly people. In this review, we highlights the symptoms, epidemiology, transmission, pathogenesis, phylogenetic analysis and future directions to control the spread of this fatal disease.

positive: Recurrence of positive SARS-CoV-2 RNA in COVID-19: A case report Abstract The ongoing outbreak of COVID-19 that began in Wuhan, China, has constituted a Public Health Emergency of International Concern, with cases confirmed in multiple countries. Currently, patients are the primary source of infection. We report a confirmed case of COVID-19 whose oropharyngeal swab test of SARS-CoV-2 RNA turned positive in convalescence. This case highlights the importance of active surveillance of SARS-CoV-2 RNA for infectivity assessment.

positive: Assessment of synthetic peptides of severe acute respiratory syndrome coronavirus recognized by long‐lasting immunity Abstract: In order to determine highly immunogenic severe acute respiratory syndrome coronavirus (SARS‐CoV) epitope peptides capable of inducing long‐lasting immunity, we first screened immunoglobulin‐G (IgG) antibodies reactive to 197 different overlapping 15‐mers from the SARS‐CoV proteins in the sera of three infected patients. Forty‐two peptides among them were reactive to the sera from all three patients. Consequently, we tested for the reactivity of these 42 peptides to patients' sera (n = 45) at 6‐month post‐infection. The significantly higher levels of IgG antibodies specific to three (S791, M207 and N161) of 42 peptides were detectable in the post‐infection sera from 23 (51%), 27 (60%) and 19 (42%) of 45 patients, respectively. These three peptides, recognized by their long‐lasting immunity, may provide a better understanding of the immunogenicity of SARS‐CoV.

positive: Cross-sectional evaluation of humoral responses against SARS-CoV-2 Spike The SARS-CoV-2 virus is responsible for the current worldwide coronavirus disease 2019 (COVID-19) pandemic, infecting millions of people and causing hundreds of thousands of deaths. The Spike glycoprotein of SARS-CoV-2 mediates viral entry and is the main target for neutralizing antibodies. Understanding the antibody response directed against SARS-CoV-2 is crucial for the development of vaccine, therapeutic and public health interventions. Here we performed a cross-sectional study on 98 SARS-CoV-2-infected individuals to evaluate humoral responses against the SARS-CoV-2 Spike. The vast majority of infected individuals elicited anti-Spike antibodies within 2 weeks after the onset of symptoms. The levels of receptor-binding domain (RBD)-specific IgG persisted overtime, while the levels of anti-RBD IgM decreased after symptoms resolution. Some of the elicited antibodies cross-reacted with other human coronaviruses in a genus-restrictive manner. While most of individuals developed neutralizing antibodies within the first two weeks of infection, the level of neutralizing activity was significantly decreased over time. Our results highlight the importance of studying the persistence of neutralizing activity upon natural SARS-CoV-2 infection.

positive: Identification of IgG antibody response to SARS-CoV-2 spike protein and its receptor binding domain does not predict rapid recovery from COVID-19 Diagnostic testing and evaluation of patient immunity against the novel severe acute respiratory syndrome (SARS) corona virus that emerged last year (SARS-CoV-2) are essential for health and economic crisis recovery of the world. It is suggested that potential acquired immunity against SARS-CoV-2 from prior exposure may be determined by detecting the presence of circulating IgG antibodies against viral antigens, such as the spike glycoprotein and its receptor binding domain (RBD). Testing our asymptomatic population for evidence of COVID-19 immunity would also offer valuable epidemiologic data to aid health care policies and health care management. Currently, there are over 100 antibody tests that are being used around the world without approval from the FDA or similar regulatory bodies, and they are mostly for rapid and qualitative assessment, with different degrees of error rates. ELISA-based testing for sensitive and rigorous quantitative assessment of SARS-CoV-2 antibodies can potentially offer mechanistic insights into the COVID-19 disease and aid communities uniquely challenged by limited financial resources and access to commercial testing products. Employing recombinant SARS-CoV-2 RBD and spike protein generated in the laboratory, we devised a quantitative ELISA for the detection of circulating serum antibodies. Serum from twenty SARS-CoV-2 RT-PCR confirmed COVID-19 hospitalized patients were used to detect circulating IgG titers against SARS-CoV-2 spike protein and RBD. Quantitative detection of IgG antibodies to the spike glycoprotein or the RBD in patient samples was not always associated with faster recovery, compared to patients with borderline antibody response to the RBD. One patient who did not develop antibodies to the RBD completely recovered from COVID-19. In surveying 99 healthy donor samples (procured between 2017-February 2020), we detected RBD antibodies in one donor from February 2020 collection with three others exhibiting antibodies to the spike protein but not the RBD. Collectively, our study suggests that more rigorous and quantitative analysis, employing large scale sample sets, is required to determine whether antibodies to SARS-CoV-2 spike protein or RBD is associated with protection from COVID-19 disease. It is also conceivable that humoral response to SARS-CoV-2 spike protein or RBD works in association with adaptive T cell response to determine clinical sequela and severity of COVID-19 disease.

positive: Characterization of protection against coronavirus infection by noninternal image antiidiotypic antibody. Previously, we have reported protective vaccination of mice against a coronavirus infection using rabbit polyclonal noninternal image Ab2gamma anti-idiotypic (anti-Id) antibody specific for a virus-neutralizing and protective monoclonal antibody (mAb) 7-10A against the viral surface S glycoprotein. To characterize further the mechanisms involved in the induction of protective immunity by this noninternal image anti-Id, plasma and splenocytes from Ab2gamma-immunized BALB/c mice were passively transferred to naive BALB/c mice, followed by viral challenge. A reproducible significant delay in mortality observed in mice to which plasma was passively transferred, together with the presence of specific in vitro neutralizing antiviral Ab3 identified the humoral immune response as the major element responsible for protection. The activation of specific and cross-reactive T lymphocytes by both virus and anti-Id in immunized mice and the absence of adoptive transfer of protection by splenocytes suggested the participation of T helper activity in the induction of protective virus-neutralizing Ab3. To obtain more defined monoclonal reagents for a better understanding of anti-Id-induced protection, mAb2 were generated against the same mAb1 7-10A and characterized. We report the successful generation of mAb2 of the gamma type. However, unlike the polyclonal Ab2gamma, they were not capable of inducing a protective immune response.

positive: Novel SARS-CoV-2 specific antibody and neutralization assays reveal wide range of humoral immune response during COVID-19 Development of antibody protection during SARS-CoV-2 (CoV-2) infection is a pressing question for public health and for vaccine development. We developed highly sensitive CoV-2-specific antibody and neutralization assays. CoV-2 Spike protein or Nucleocapsid protein specific IgG antibodies at titers more than 1:100,000 were detectable in all PCR+ subjects (n=87) and were absent in the negative controls. Other isotype antibodies (IgA, IgG1-4) were also detected. CoV-2 neutralization was determined in COVID-19 and convalescent plasma up to 10,000-fold dilution, using Spike protein pseudotyped lentiviruses, which was also blocked by neutralizing antibodies (NAbs). Hospitalized patients had up to 3000-fold higher antibody and neutralization titers compared to outpatients or convalescent plasma donors. Further, subjects who donated plasma further out from the diagnosis of COVID-19 appeared to have lower titers. Interestingly, some COVID-19 patients also contained NAbs against SARS Spike protein pseudovirus. Together these results demonstrate the high specificity and sensitivity of our assays, which may impact understanding the quality or duration of the antibody response during COVID-19 and in determining the effectiveness of potential vaccines.

positive: Long‐term coexistence of SARS‐CoV‐2 with antibody response in COVID‐19 patients Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infection causing coronavirus disease 2019 (COVID‐19) has spread worldwide. Whether antibodies are important for the adaptive immune responses against SARS‐CoV‐2 infection needs to be determined. Here, 26 cases of COVID‐19 in Jinan, China, were examined and shown to be mild or with common clinical symptoms, and no case of severe symptoms was found among these patients. Strikingly, a subset of these patients had SARS‐CoV‐2 and virus‐specific IgG coexist for an unexpectedly long time, with two cases for up to 50 days. One COVID‐19 patient who did not produce any SARS‐CoV‐2–bound IgG successfully cleared SARS‐CoV‐2 after 46 days of illness, revealing that without antibody‐mediated adaptive immunity, innate immunity alone may still be powerful enough to eliminate SARS‐CoV‐2. This report may provide a basis for further analysis of both innate and adaptive immunity in SARS‐CoV‐2 clearance, especially in nonsevere cases.

positive: Passive Immunity for Coronavirus Disease 2019: A Commentary on Therapeutic Aspects Including Convalescent Plasma. In the ongoing pandemic of coronavirus disease 2019 (COVID-19), the novel virus SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) is infecting a naïve population. The innate immunity of the infected patient is unable to mount an effective defense, resulting in a severe illness with substantial morbidity and mortality. As most treatment modalities including antivirals and anti-inflammatory agents are mostly ineffective, an immunological approach is needed. The mechanism of innate immunity to this viral illness is not fully understood. Passive immunity becomes an important avenue for the management of these patients. In this article, the immune responses of COVID-19 patients are reviewed. As SARS-CoV-2 has many characteristics in common with two other viruses, SARS-CoV that cause severe acute respiratory syndrome (SARS) and MERS-CoV (Middle East respiratory syndrome coronavirus) that causes Middle East respiratory syndrome (MERS), the experiences learned from the use of passive immunity in treatment can be applied to COVID-19. The immune response includes the appearance of immunoglobulin M followed by immunoglobulin G and neutralizing antibodies. Convalescent plasma obtained from patients recovered from the illness with high titers of neutralizing antibodies was successful in treating many COVID-19 patients. The factors that determine responses as compared with those seen in SARS and MERS are also reviewed. As there are no approved vaccines against all three viruses, it remains a challenge in the ongoing development for an effective vaccine for COVID-19.

positive: Macrophage Pattern Recognition Receptors in Immunity, Homeostasis and Self Tolerance Macrophages, a major component of innate immune defence, express a large repertoire of different classes of pattern recognition receptors and other surface antigens which determine the immunologic and homeostatic potential of these versatile cells. In the light of present knowledge of macrophage surface antigens, we discuss self versus nonself recognition, microbicidal effector functions and self tolerance in the innate immune system.

positive: Microneedle array delivered recombinant coronavirus vaccines: Immunogenicity and rapid translational development Abstract Background Coronaviruses pose a serious threat to global health as evidenced by Severe Acute Respiratory Syndrome (SARS), Middle East Respiratory Syndrome (MERS), and COVID-19. SARS Coronavirus (SARS-CoV), MERS Coronavirus (MERS-CoV), and the novel coronavirus, previously dubbed 2019-nCoV, and now officially named SARS-CoV-2, are the causative agents of the SARS, MERS, and COVID-19 disease outbreaks, respectively. Safe vaccines that rapidly induce potent and long-lasting virus-specific immune responses against these infectious agents are urgently needed. The coronavirus spike (S) protein, a characteristic structural component of the viral envelope, is considered a key target for vaccines for the prevention of coronavirus infection. Methods We first generated codon optimized MERS-S1 subunit vaccines fused with a foldon trimerization domain to mimic the native viral structure. In variant constructs, we engineered immune stimulants (RS09 or flagellin, as TLR4 or TLR5 agonists, respectively) into this trimeric design. We comprehensively tested the pre-clinical immunogenicity of MERS-CoV vaccines in mice when delivered subcutaneously by traditional needle injection, or intracutaneously by dissolving microneedle arrays (MNAs) by evaluating virus specific IgG antibodies in the serum of vaccinated mice by ELISA and using virus neutralization assays. Driven by the urgent need for COVID-19 vaccines, we utilized this strategy to rapidly develop MNA SARS-CoV-2 subunit vaccines and tested their pre-clinical immunogenicity in vivo by exploiting our substantial experience with MNA MERS-CoV vaccines. Findings Here we describe the development of MNA delivered MERS-CoV vaccines and their pre-clinical immunogenicity. Specifically, MNA delivered MERS-S1 subunit vaccines elicited strong and long-lasting antigen-specific antibody responses. Building on our ongoing efforts to develop MERS-CoV vaccines, promising immunogenicity of MNA-delivered MERS-CoV vaccines, and our experience with MNA fabrication and delivery, including clinical trials, we rapidly designed and produced clinically-translatable MNA SARS-CoV-2 subunit vaccines within 4 weeks of the identification of the SARS-CoV-2 S1 sequence. Most importantly, these MNA delivered SARS-CoV-2 S1 subunit vaccines elicited potent antigen-specific antibody responses that were evident beginning 2 weeks after immunization. Interpretation MNA delivery of coronaviruses-S1 subunit vaccines is a promising immunization strategy against coronavirus infection. Progressive scientific and technological efforts enable quicker responses to emerging pandemics. Our ongoing efforts to develop MNA-MERS-S1 subunit vaccines enabled us to rapidly design and produce MNA SARS-CoV-2 subunit vaccines capable of inducing potent virus-specific antibody responses. Collectively, our results support the clinical development of MNA delivered recombinant protein subunit vaccines against SARS, MERS, COVID-19, and other emerging infectious diseases.

positive: Antibody tests in detecting SARS-CoV-2 infection: a meta-analysis With the emergence of SARS-CoV-2 and the associated Coronavirus disease 2019 (COVID-19), there is an imperative need for diagnostic tests that can identify the infection. Although Nucleic Acid Test (NAT) is considered to be the gold standard, serological tests based on antibodies could be very helpful. However, individual studies measuring the accuracy of the various tests are usually underpowered and inconsistent, thus, a comparison of different tests is needed. We performed a systematic review and meta-analysis following the PRISMA guidelines. We conducted the literature search in PubMed, medRxiv and bioRxiv. For the statistical analysis we used the bivariate method for meta-analysis of diagnostic tests pooling sensitivities and specificities. We evaluated IgM and IgG tests based on Enzyme-linked immunosorbent assay (ELISA), Chemiluminescence Enzyme Immunoassays (CLIA), Fluorescence Immunoassays (FIA) and the point-of-care (POC) Lateral Flow Immunoassays (LFIA) that are based on immunochromatography. In total, we identified 38 eligible studies that include data from 7,848 individuals. The analyses showed that tests using the S antigen are more sensitive than N antigen-based tests. IgG tests perform better compared to IgM ones, and show better sensitivity when the samples were taken longer after the onset of symptoms. Moreover, irrespective of the method, a combined IgG/IgM test seems to be a better choice in terms of sensitivity than measuring either antibody type alone. All methods yielded high specificity with some of them (ELISA and LFIA) reaching levels around 99%. ELISA- and CLIA-based methods performed better in terms of sensitivity (90-94%) followed by LFIA and FIA with sensitivities ranging from 80% to 86%. ELISA tests could be a safer choice at this stage of the pandemic. POC tests (LFIA), that are more attractive for large seroprevalence studies show high specificity but lower sensitivity and this should be taken into account when designing and performing seroprevalence studies.

positive: Immunization with the receptor–binding domain of SARS-CoV-2 elicits antibodies cross-neutralizing SARS-CoV-2 and SARS-CoV without antibody-dependent enhancement Recently emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the pathogen responsible for the ongoing coronavirus disease 2019 (COVID-19) pandemic. Currently, there is no vaccine available for preventing SARS-CoV-2 infection. Like closely related severe acute respiratory syndrome coronavirus (SARS-CoV), SARS-CoV-2 also uses its receptor-binding domain (RBD) on the spike (S) protein to engage the host receptor, human angiotensin-converting enzyme 2 (ACE2), facilitating subsequent viral entry. Here we report the immunogenicity and vaccine potential of SARS-CoV-2 RBD (SARS2-RBD)-based recombinant proteins. Immunization with SARS2-RBD recombinant proteins potently induced a multi-functional antibody response in mice. The resulting antisera could efficiently block the interaction between SARS2-RBD and ACE2, inhibit S-mediated cell-cell fusion, and neutralize both SARS-CoV-2 pseudovirus entry and authentic SARS-CoV-2 infection. In addition, the anti-RBD sera also exhibited cross binding, ACE2-blockade, and neutralization effects towards SARS-CoV. More importantly, we found that the anti-RBD sera did not promote antibody-dependent enhancement of either SARS-CoV-2 pseudovirus entry or authentic virus infection of Fc receptor-bearing cells. These findings provide a solid foundation for developing RBD-based subunit vaccines for SARS-CoV2.

positive: SARS-CoV-2 infection in children: Transmission dynamics and clinical characteristics

positive: Serologic cross-reactivity of SARS-CoV-2 with endemic and seasonal Betacoronaviruses In order to properly understand the spread of SARS-CoV-2 infection and development of humoral immunity, researchers have evaluated the presence of serum antibodies of people worldwide experiencing the pandemic. These studies rely on the use of recombinant proteins from the viral genome in order to identify serum antibodies that recognize SARS-CoV-2 epitopes. Here, we discuss the cross-reactivity potential of SARS-CoV-2 antibodies with the full spike proteins of four other Betacoronaviruses that cause disease in humans, MERS-CoV, SARS-CoV, HCoV-OC43, and HCoV-HKU1. Using enzyme-linked immunosorbent assays (ELISAs), we detected the potential cross-reactivity of antibodies against SARS-CoV-2 towards the four other coronaviruses, with the strongest cross-recognition between SARS-CoV-2 and SARS /MERS-CoV antibodies, as expected based on sequence homology of their respective spike proteins. Further analysis of cross-reactivity could provide informative data that could lead to intelligently designed pan-coronavirus therapeutics or vaccines.

positive: Could BCG be used to protect against COVID-19? Nearly 100 years since it was first used in humans as a vaccine for tuberculosis, Bacillus Calmette–Guérin (BCG) has been suggested as a possible agent to prevent coronavirus disease 2019 (COVID-19). A number of studies are underway to investigate this possibility but — even if they prove effective — many questions will remain.

positive: Direct observation of repeated infections with endemic coronaviruses Background: While the mechanisms of adaptive immunity to pandemic coronavirus SARS-CoV-2 are still unknown, the immune response to the widespread endemic coronaviruses HKU1, 229E, NL63 and OC43 provide a useful reference for understanding repeat infection risk. Methods: Here we used data from proactive sampling carried out in New York City from fall 2016 to spring 2018. We combined weekly nasal swab collection with self-reports of respiratory symptoms from 191 participants to investigate the profile of recurring infections with endemic coronaviruses. Results: During the study, 12 individuals tested positive multiple times for the same coronavirus. We found no significant difference between the probability of testing positive at least once and the probability of a recurrence for the beta-coronaviruses HKU1 and OC43 at 34 weeks after enrollment/first infection. We also found no significant association between repeat infections and symptom severity but strong association between symptom severity and belonging to the same family. Conclusion: This study provides evidence that re-infections with the same endemic coronavirus are not atypical in a time window shorter than 1 year and that the genetic basis of innate immune response may be a greater determinant of infection severity than immune memory acquired after a previous infection.

positive: Antigenic evolution on global scale reveals potential natural selection of SARS-CoV-2 by pre-existing cross-reactive T cell immunity The mutation pattern of severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) is constantly changing with the places of transmission, but the reason remains to be revealed. Here, we presented the study that comprehensively analyzed the potential selective pressure of immune system restriction, which can drive mutations in circulating SARS-CoV-2 isolates. The results showed that the most common mutation sites of SARS-CoV-2 proteins were located on the non-structural protein ORF1ab and the structural protein Spike. Further analysis revealed mutations in cross-reactive epitopes between SARS-CoV-2 and seasonal coronavirus may help SARS-CoV-2 to escape cellular immunity under the long-term and large-scale community transmission. Meanwhile, the mutations on Spike protein may enhance the ability of SARS-CoV-2 to enter the host cells and escape the recognition of B-cell immunity. This study will increase the understanding of the evolutionary direction and warn about the potential immune escape ability of SARS-CoV-2, which may provide important guidance for the potential vaccine design.

positive: Universal coronavirus vaccines: the time to start is now The continued explosive spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) despite aggressive public health measures has triggered an unprecedented international vaccine effort. However, correlates of protection, which can help guide intelligent vaccine design, are not known for SARS-CoV-2. Research on influenza immunity and vaccine development may provide valuable lessons for coronavirus efforts, especially considering similarities in rapid evolutionary potential. The apparent inevitability of future novel coronavirus outbreaks must prompt work on a universal coronavirus vaccine.

positive: [Potent neutralization antibody elicited in mice by SARS-associated coronavirus spike protein S1 domain]. OBJECTIVE To study the antigenicity of SARS associated coronavirus (CoV) spike S1 (12-672Aa) domain. METHODS BALB/c mice were immunized with a plasmid bearing codon-optimized SARS-CoV (Tor2 strain) S1 domain and then boosted with purified S1 protein; the SARS-CoV specific IgG antibody was tested by ELISA and neutralization antibody was determined by in vitro microneutralization assay. RESULTS S1 domain of SARS-CoV spike, which has been demonstrated harboring the receptor binding domain, successfully elicited SARS-CoV specific IgG antibody in mouse after combined immunization with DNA and purified S1 protein; the antibody elicited solely by S1 could potently neutralize SARS-CoV (HKU-39849) in vitro, 50% of 1 000 TCID50 SARS-CoV challenged cells were protected from viral infection by a 1:1499.68 dilution of mice sera immunized with S1 protein, but negative control sera showed no protection. CONCLUSION S1 domain of SARS-CoV spike protein, which is responsible for receptor binding, can efficiently and sufficiently induce highly potent neutralizing antibody in mice. This result suggested that S1 domain could be an effective subunit vaccines against SARS-CoV.

positive: Differences in antibody kinetics and functionality between severe and mild SARS-CoV-2 infections. We determined and compared the humoral immune response in severe, hospitalized and mild, non-hospitalized COVID-19 patients. Severe patients (n=38) develop a robust antibody response to SARS-CoV-2, including IgG and IgA antibodies. The geometric mean 50% virus neutralization titer is 1:240. SARS-CoV-2 infected hospital personnel (n=24), who developed mild symptoms necessitating leave of absence, self-isolation, but not hospitalization, 75 % develop antibodies, but with low/absent virus neutralization (60% < 1:20). While severe COVID-19 patients develop a strong antibody response, mild SARS-CoV-2 infections induce a modest antibody response. Long term monitoring will show whether these responses predict protection against future infections.

positive: Acute inflammation and pathogenesis of SARS-CoV-2 infection: Cannabidiol as a potential anti-inflammatory treatment?

positive: Coronavirus derived expression systems Abstract Both helper dependent expression systems, based on two components, and single genomes constructed by targeted recombination, or by using infectious cDNA clones, have been developed. The sequences that regulate transcription have been characterized mainly using helper dependent expression systems and it will now be possible to validate them using single genomes. The genome of coronaviruses has been engineered by modification of the infectious cDNA leading to an efficient (>20 μg ml−1) and stable (>20 passages) expression of the foreign gene. The possibility of engineering the tissue and species tropism to target expression to different organs and animal species, including humans, increases the potential of coronaviruses as vectors. Thus, coronaviruses are promising virus vectors for vaccine development and, possibly, for gene therapy.

positive: Meta-analysis of transcriptomes of SARS-Cov2 infected human lung epithelial cells identifies transmembrane serine proteases co-expressed with ACE2 and biological processes related to viral entry, immunity, inflammation and cellular stress The COVID-19 pandemic resulting from the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) which emerged in December 2019 in the Chinese city of Wuhan in the province Hubei has placed immense burden on national economies and global health. At present neither vaccination nor therapies are available although several antiviral agents such as remdesivir, originally an Ebola drug, nelfinavir, an HIV-1 protease inhibitor and other drugs such as lopinavir have been evaluated. Here, we performed a meta-analysis of RNA-sequencing data from three studies employing human lung epithelial cells. Of these one focused on lung epithelial cells infected with SARS-CoV-2. We aimed at identifying genes co-expressed with angiotensin I converting enzyme 2 (ACE2) the human cell entry receptor of SARS-CoV-2, and unveiled several genes correlated or inversely correlated with high significance, among the most significant of these was the transmembrane serine protease 4 (TMPRSS4). Serine proteases are known to be involved in the infection process by priming the virus spike protein. Pathway analysis revealed papilloma virus infection amongst the most significantly correlated pathways. Gene Ontologies revealed regulation of viral life cycle, immune responses, pro-inflammatory responses-several interleukins such as IL6, IL1, IL20 and IL33, IFI16 regulating the interferon response to a virus, chemo-attraction of macrophages, last and not least cellular stress resulting from activated Reactive Oxygen Species. We believe that this dataset will aid in a better understanding of the molecular mechanism(s) underlying COVID-19.

positive: A systematic review of antibody mediated immunity to coronaviruses: antibody kinetics, correlates of protection, and association of antibody responses with severity of disease The duration and nature of immunity generated in response to SARS-CoV-2 infection is unknown. Many public health responses and modeled scenarios for COVID-19 outbreaks caused by SARSCoV-2 assume that infection results in an immune response that protects individuals from future infections or illness for some amount of time. The timescale of protection is a critical determinant of the future impact of the pathogen. The presence or absence of protective immunity due to infection or vaccination (when available) will affect future transmission and illness severity. The dynamics of immunity and nature of protection are relevant to discussions surrounding therapeutic use of convalescent sera as well as efforts to identify individuals with protective immunity. Here, we review the scientific literature on antibody immunity to coronaviruses, including SARS-CoV-2 as well as the related SARS-CoV-1, MERS-CoV and human endemic coronaviruses (HCoVs). We reviewed 1281 abstracts and identified 322 manuscripts relevant to 5 areas of focus: 1) antibody kinetics, 2) correlates of protection, 3) immunopathogenesis, 4) antigenic diversity and cross-reactivity, and 5) population seroprevalence. While studies of SARS-CoV-2 are necessary to determine immune responses to it, evidence from other coronaviruses can provide clues and guide future research.

positive: COVID‐19: Herd Immunity and Convalescent Plasma Transfer Therapy Coronavirus disease 2019 (COVID‐19), caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS‐CoV‐2), has spread worldwide triggering a pandemic. Its first case was reported in Wuhan, the capital of China's Hubei province, and since then it has spread across world becoming one of the worst pandemics in the history of mankind(1). Its basic reproductive number (R(0)) has been determined to be 2‐3(2). This article is protected by copyright. All rights reserved.

positive: Global efforts on vaccines for COVID-19: Since, sooner or later, we all will catch the coronavirus COVID-19 is an emerging infectious disease that has turned into a pandemic. It spreads through droplet transmission of the new coronavirus SARS-CoV-2. It is an RNA virus displaying a spike protein as the major surface protein with significant sequence similarity to SARS-CoV which causes severe acute respiratory syndrome. The receptor binding domain of the spike protein interacts with the human angiotensin converting enzyme 2 and is considered as the antigenic determinant for stimulating an immune response. While multiple candidate vaccines are currently under different stages of development, there are no known therapeutic interventions at the moment. This review describes the key genetic features that are being considered for generating vaccine candidates by employing innovative technologies. It also highlights the global efforts being undertaken to deliver vaccines for COVID-19 through unprecedented international cooperation and future challenges post development.

positive: Dissecting antibody-mediated protection against SARS-CoV-2 Understanding the properties and mechanisms by which antibodies provide protection is essential to defining immunity. Although neutralizing antibodies have been proposed as a potential key mechanism of protection against many viral pathogens, antibodies mediate additional immune functions that may have both protective and pathological consequences. Dissecting these properties against SARS-CoV-2 is likely necessary for defining metrics of immunity that will inform the design of vaccines and therapeutics and improve clinical management.

positive: Virus-host interactome and proteomic survey of PMBCs from COVID-19 patients reveal potential virulence factors influencing SARS-CoV-2 pathogenesis The ongoing coronavirus disease (COVID-19) pandemic caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is a global public health concern due to relatively easy person-to-person transmission and the current lack of effective antiviral therapy. However, the exact molecular mechanisms of SARS-CoV-2 pathogenesis remain largely unknown. We exploited an integrated proteomics approach to systematically investigate intra-viral and virus-host interactomes for the identification of unrealized SARS-CoV-2 host targets and participation of cellular proteins in the response to viral infection using peripheral blood mononuclear cells (PBMCs) isolated from COVID-19 patients. Using this approach, we elucidated 251 host proteins targeted by SARS-CoV-2 and more than 200 host proteins that are significantly perturbed in COVID-19 derived PBMCs. From the interactome, we further identified that non-structural protein nsp9 and nsp10 interact with NKRF, a NF-КB repressor, and may precipitate the strong IL-8/IL-6 mediated chemotaxis of neutrophils and overexuberant host inflammatory response observed in COVID-19 patients. Our integrative study not only presents a systematic examination of SARS-CoV-2-induced perturbation of host targets and cellular networks to reflect disease etiology, but also reveals insights into the mechanisms by which SARS-CoV-2 triggers cytokine storms and represents a powerful resource in the quest for therapeutic intervention.

positive: Long-lived memory T lymphocyte responses against SARS coronavirus nucleocapsid protein in SARS-recovered patients Abstract The nucleocapsid (N) protein is a structural component of severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV) and can induce antibody responses in SARS patients during infection. However, it is not known whether SARS-CoV N protein can induce a long persistence of memory T-cell response in human. In this study, we found that peripheral blood mononuclear cells (PBMCs) from fully recovered SARS individuals rapidly produced IFN-γ and IL-2 following stimulation with a pool of overlapping peptides that cover the entire N protein sequence. The N-specific IFN-γ+CD4+ T cells were mainly composed of CD45RA−CCR7+CD62L− cells, whereas IFN-γ+CD8+ memory T cells were mostly contained within CD45RA+CCR7−CD62L− cell population. Epitope mapping study indicated that a cluster of overlapping peptides located in the C-terminal region (amino acids [aa] 331 to 362) of N protein contained at least two different T-cell epitopes. The results indicated that human memory T-cell responses specific for SARS-CoV N protein could persist for 2 years in the absence of antigen, which would be a valuable for the design of effective vaccines against SARS-CoV and for basic studies of human T-cell memory.

positive: Analysis of adaptive immune cell populations and phenotypes in the patients infected by SARS-CoV-2 Coronavirus disease-2019 (COVID-19), caused by SARS-CoV-2, has rapidly spread to most of countries in the world, threatening the health and lives of many people. Unfortunately, information regarding the immunological characteristics in COVID-19 patients remains limited. Here we collected the blood samples from 18 healthy donors (HD) and 38 COVID-19 patients to analyze changes in the adaptive immune cell populations and phenotypes. In comparison to HD, the lymphocyte percentage was slightly decreased, the percentages of CD4 and CD8 T cells in lymphocytes are similar, whereas B cell percentage increased in COVID-19 patients. T cells, especially CD8 T cells, showed an enhanced expression of late activation marker CD25 and exhaustion marker PD-1. Importantly, SARS-CoV-2 induced an increased percentage of T follicular helpher (Tfh)- and germinal center B-like (GCB-like) cells in the blood. However, the parameters in COVD-19 patients remained unchanged across various age groups. Therefore, we demonstrated that the T and B cells can be activated normally and exhibit functional features. These data provide a clue that the adaptive immunity in most people could be primed to induce a significant immune response against SARS-CoV-2 infection upon receiving standard medical care.

positive: Prior infection of pigs with a recent human H3N2 influenza virus confers minimal cross‐protection against a European swine H3N2 virus BACKGROUND: H3N2 influenza viruses circulating in humans and European pigs originate from the pandemic A/Hong Kong/68 virus. Because of slower antigenic drift in swine, the antigenic divergence between swine and human viruses has been increasing. It remains unknown to what extent this results in a reduced cross‐protection between recent human and swine H3N2 influenza viruses. OBJECTIVES: We examined whether prior infection of pigs with an old [A/Victoria/3/75 (A/Vic/75)] or a more recent [A/Wisconsin/67/05 (A/Wis/05)] human H3N2 virus protected against a European swine H3N2 virus [sw/Gent/172/08 (sw/Gent/08)]. Genetic and antigenic relationships between sw/Gent/08 and a selection of human H3N2 viruses were also assessed. RESULTS: After challenge with sw/Gent/08, all challenge controls had high virus titers in the entire respiratory tract at 3 days post‐challenge and nasal virus excretion for 5–6 days. Prior infection with sw/Gent/08 or A/Vic/75 offered complete virological protection against challenge. Pigs previously inoculated with A/Wis/05 showed similar virus titers in the respiratory tract as challenge controls, but the mean duration of nasal shedding was 1·3 days shorter. Unlike sw/Gent/08‐ and A/Vic/75‐inoculated pigs, A/Wis/05‐inoculated pigs lacked cross‐reactive neutralizing antibodies against sw/Gent/08 before challenge, but they showed a more rapid antibody response to sw/Gent/08 than challenge controls after challenge. Cross‐protection and serological responses correlated with genetic and antigenic differences. CONCLUSIONS: Infection immunity to a recent human H3N2 virus confers minimal cross‐protection against a European swine H3N2 virus. We discuss our findings with regard to the recent zoonotic infections of humans in the United States with a swine‐origin H3N2 variant virus.

positive: A SARS DNA Vaccine Induces Neutralizing Antibody and Cellular Immune Responses in Healthy Adults in a Phase I Clinical Trial BACKGROUND: The severe acute respiratory syndrome (SARS) virus is a member of the Coronaviridae (CoV) family that first appeared in the Guangdong Province of China in 2002 and was recognized as an emerging infectious disease in March 2003. Over 8,000 cases and 900 deaths occurred during the epidemic. We report the safety and immunogenicity of a SARS DNA vaccine in a Phase I human study. METHODS: A single-plasmid DNA vaccine encoding the Spike (S) glycoprotein was evaluated in 10 healthy adults. Nine subjects completed the 3 dose vaccination schedule and were evaluated for vaccine safety and immune responses. Immune response was assessed by intracellular cytokine staining (ICS), ELISpot, ELISA, and neutralization assays. RESULTS: The vaccine was well-tolerated. SARS-CoV-specific antibody was detected by ELISA in 8 of 10 subjects and neutralizing antibody was detected in all subjects who received 3 doses of vaccine. SARS-CoV-specific CD4+ T cell responses were detected in all vaccinees, and CD8+ T cell responses in ∼20% of individuals. CONCLUSIONS: The VRC SARS DNA vaccine was well tolerated and produced cellular immune responses and neutralizing antibody in healthy adults.

negative: Comparative analysis of innate immune responses following infection of newborn calves with bovine rotavirus and bovine coronavirus. Bovine rotavirus (BRV) and bovine coronavirus (BCV) are important causes of diarrhoea and death in newborn calves. Although these viruses belong to distinct viral classes, they both infect intestinal epithelial cells and induce similar clinical symptoms. Rotavirus usually causes an acute infection, but coronavirus infection can persist and reoccur in adults. Differences in viral structure and clinical outcome prompted us to postulate that innate mucosal immune responses would be markedly different following rotavirus and coronavirus infections. To address this hypothesis, gene expression following BRV and BCV infection was analysed in surgically prepared intestinal loops from 1-day-old colostrum-deprived calves. Gene expression was profiled at 18 h post-infection using bovine cDNA microarrays; the majority of differentially expressed significant genes were associated with the cell cycle and innate immune responses. A select group of these genes was validated by quantitative real-time PCR (qRT-PCR). The expression of genes associated with interferons (IFNs), cytokines and Toll-like receptors, which were not present on the microarray, was analysed further by qRT-PCR. Strong activation of TLR3, IL-6 and p65 was observed in BRV-infected host tissues, but not in tissues infected with BCV. Both viruses also downregulated IFN- and pro-inflammatory cytokine-associated pathways. In vitro studies confirmed that IFN inhibited viral replication. All of these results together suggested either that very early events of host responses at 18 h post-infection were being observed, or that both viruses have unique effective strategies to evade host immune responses.

negative: P136 Combined action of type I and type III IFN restricts initial replication of SARS-coronavirus in the lung but fails to inhibit systemic virus spread Introduction STAT1-deficient mice are more susceptible to infection with SARS-Coronavirus (SARS-CoV) than type I IFN receptor-deficient mice. The increased susceptibility of STAT1-deficient mice is potentially due to the lack of functional type III IFN (IFN-λ) signalling. Methods We used mice lacking functional receptors for both type I and type III IFN (dKO) to evaluate the possibility that type III IFN plays a decisive role in SARS-CoV protection. Results We found that viral peak titres in lungs of dKO and STAT1-deficient mice were similar, although significantly higher than in wild-type mice. The kinetics of viral clearance from the lung was also comparable in dKO and STAT1-deficient mice. Surprisingly, however, infected dKO mice remained healthy, whereas infected STAT1-deficient mice developed liver pathology and eventually succumbed to neurological disease. Conclusion Our data suggest that the failure of STAT1-deficient mice to efficiently control initial SARS-CoV replication in the lung is due to impaired type I and type III IFN signaling, whereas the failure to control subsequent systemic viral spread is due to unrelated defects in STAT1-deficient mice.

negative: Obstacles and advances in SARS vaccine development The emergence of the severe acute respiratory syndrome (SARS) that resulted in a pandemic in 2003 spurred a flurry of interest in the development of vaccines to prevent and treat the potentially deadly viral infection. Researchers around the world pooled their scientific resources and shared early data in an unprecedented manner in light of the impending public health crisis. There are still large gaps in knowledge about the pathogenesis of this virus. While significant advances have been made in the development of animal models, the practicality of their use may be hampered by a lack of pathological similarity with human disease. Described here are issues related to progress in vaccine development and the obstacles that lie ahead for both researchers and regulatory agencies.

negative: Updated Vaccination Recommendations for Carnivores

negative: Recommendations for coronavirus infection in rheumatic diseases treated with biologic therapy The Coronavirus-associated disease, that was first identified in 2019 in China (CoViD-19), is a pandemic caused by a bat-derived beta-coronavirus, named SARS-CoV2. It shares homology with SARS and MERS-CoV, responsible for past outbreaks in China and in Middle East. SARS-CoV2 spread from China where the first infections were described in December 2019 and is responsible for the respiratory symptoms that can lead to acute respiratory distress syndrome. A cytokine storm has been shown in patients who develop fatal complications, as observed in past coronavirus infections. The management includes ventilatory support and broad-spectrum antiviral drugs, empirically utilized, as a targeted therapy and vaccines have not been developed. Based upon our limited knowledge on the pathogenesis of CoViD-19, a potential role of some anti-rheumatic drugs may be hypothesized, acting as direct antivirals or targeting host immune response. Antimalarial drugs, commonly used in rheumatology, may alter the lysosomal proteases that mediates the viral entry into the cell and have demonstrated efficacy in improving the infection. Anti-IL-1 and anti-IL-6 may interfere with the cytokine storm in severe cases and use of tocilizumab has shown good outcomes in a small cohort. Baricitinib has both antiviral and anti-inflammatory properties. Checkpoints inhibitors such as anti-CD200 and anti-PD1 could have a role in the treatment of CoViD-19. Rheumatic disease patients taking immunosuppressive drugs should be recommended to maintain the chronic therapy, prevent infection by avoiding social contacts and pausing immunosuppressants in case of infection. National and international registries are being created to collect data on rheumatic patients with CoViD-19.

negative: Full spectrum of COVID-19 severity still being depicted

negative: Deep sequencing identifies viral and wasp genes with potential roles in replication of Microplitis demolitor Bracovirus. Viruses in the genus Bracovirus (BV) (Polydnaviridae) are symbionts of parasitoid wasps that specifically replicate in the ovaries of females. Recent analysis of expressed sequence tags from two wasp species, Cotesia congregata and Chelonus inanitus, identified transcripts related to 24 different nudivirus genes. These results together with other data strongly indicate that BVs evolved from a nudivirus ancestor. However, it remains unclear whether BV-carrying wasps contain other nudivirus-like genes and what types of wasp genes may also be required for BV replication. Microplitis demolitor carries Microplitis demolitor bracovirus (MdBV). Here we characterized MdBV replication and performed massively parallel sequencing of M. demolitor ovary transcripts. Our results indicated that MdBV replication begins in stage 2 pupae and continues in adults. Analysis of prereplication- and active-replication-stage ovary RNAs yielded 22 Gb of sequence that assembled into 66,425 transcripts. This breadth of sampling indicated that a large percentage of genes in the M. demolitor genome were sequenced. A total of 41 nudivirus-like transcripts were identified, of which a majority were highly expressed during MdBV replication. Our results also identified a suite of wasp genes that were highly expressed during MdBV replication. Among these products were several transcripts with conserved roles in regulating locus-specific DNA amplification by eukaryotes. Overall, our data set together with prior results likely identify the majority of nudivirus-related genes that are transcriptionally functional during BV replication. Our results also suggest that amplification of proviral DNAs for packaging into BV virions may depend upon the replication machinery of wasps.

negative: Transmissible Gastroenteritis Virus Infection Up-Regulates FcRn Expression via Nucleocapsid Protein and Secretion of TGF-β in Porcine Intestinal Epithelial Cells Transmissible gastroenteritis virus (TGEV) is a porcine intestinal coronavirus that causes fatal severe watery diarrhea in piglets. The neonatal Fc receptor (FcRn) is the only IgG transport receptor, its expression on mucosal surfaces is triggered upon viral stimulation, which significantly enhances mucosal immunity. We utilized TGEV as a model pathogen to explore the role of FcRn in resisting viral invasion in overall intestinal mucosal immunity. TGEV induced FcRn expression by activating NF-κB signaling in porcine small intestinal epithelial (IPEC-J2) cells, however, the underlying mechanisms are unclear. First, using small interfering RNAs, we found that TGEV up-regulated FcRn expression via TLR3, TLR9 and RIG-I. Moreover, TGEV induced IL-1β, IL-6, IL-8, TGF-β, and TNF-α production. TGF-β-stimulated IPEC-J2 cells highly up-regulated FcRn expression, while treatment with a JNK-specific inhibitor down-regulated the expression. TGEV nucleocapsid (N) protein also enhanced FcRn promoter activity via the NF-κB signaling pathway and its central region (aa 128–252) was essential for FcRn activation. Additionally, N protein-mediated FcRn up-regulation promotes IgG transcytosis. Thus, TGEV N protein and TGF-β up-regulated FcRn expression, further clarifying the molecular mechanism of up-regulation of FcRn expression by TGEV.

negative: BCG vaccine protection from severe coronavirus disease 2019 (COVID-19). A series of epidemiological explorations has suggested a negative association between national bacillus Calmette-Guérin (BCG) vaccination policy and the prevalence and mortality of coronavirus disease 2019 (COVID-19). However, these comparisons are difficult to validate due to broad differences between countries such as socioeconomic status, demographic structure, rural vs. urban settings, time of arrival of the pandemic, number of diagnostic tests and criteria for testing, and national control strategies to limit the spread of COVID-19. We review evidence for a potential biological basis of BCG cross-protection from severe COVID-19, and refine the epidemiological analysis to mitigate effects of potentially confounding factors (e.g., stage of the COVID-19 epidemic, development, rurality, population density, and age structure). A strong correlation between the BCG index, an estimation of the degree of universal BCG vaccination deployment in a country, and COVID-19 mortality in different socially similar European countries was observed (r 2 = 0.88; P = 8 × 10-7), indicating that every 10% increase in the BCG index was associated with a 10.4% reduction in COVID-19 mortality. Results fail to confirm the null hypothesis of no association between BCG vaccination and COVID-19 mortality, and suggest that BCG could have a protective effect. Nevertheless, the analyses are restricted to coarse-scale signals and should be considered with caution. BCG vaccination clinical trials are required to corroborate the patterns detected here, and to establish causality between BCG vaccination and protection from severe COVID-19. Public health implications of a plausible BCG cross-protection from severe COVID-19 are discussed.

negative: Systemic immunobiological, immunosuppressant, and oncologic agents for the treatment of dermatologic diseases during the SARS-CoV-2 (COVID-19) pandemic emergency: A quick review for a quick consultation The precision medicine era has helped to better manage patients with immunological and oncological diseases, improving the quality of life of this class of patients. Regarding the management of these patients and positivity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), currently, limited data are available and information is evolving. In this quick review, we have analyzed the mechanisms of action and related infective risk of drugs used for the treatment of immune-mediated and oncologic skin conditions during the daily clinical practice. In general, immunosuppressant and antineoplastic agents for dermatologic treatments do not require suspension and do not require special measures, if not those commonly observed. In the case of a coronavirus disease (COVID-19) patient with complications (such as pneumonia, respiratory failure), treatment suspension should always be considered after taking into account the general condition of the patient, the risk-benefit ratio, and the pathophysiology of COVID-19 infection. The COVID-19 emergency pandemic does not imply undertreatment of existing skin conditions, which together with the SARS-CoV-2 infection may jeopardize the patient's life.

negative: MERS-CoV and H5N1 influenza virus antagonize antigen presentation by altering the epigenetic landscape Convergent evolution dictates that diverse groups of viruses will target both similar and distinct host pathways to manipulate the immune response and improve infection. In this study, we sought to leverage this uneven viral antagonism to identify critical host factors that govern disease outcome. Utilizing a systems-based approach, we examined differential regulation of IFN-γ–dependent genes following infection with robust respiratory viruses including influenza viruses [A/influenza/Vietnam/1203/2004 (H5N1-VN1203) and A/influenza/California/04/2009 (H1N1-CA04)] and coronaviruses [severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome CoV (MERS-CoV)]. Categorizing by function, we observed down-regulation of gene expression associated with antigen presentation following both H5N1-VN1203 and MERS-CoV infection. Further examination revealed global down-regulation of antigen-presentation gene expression, which was confirmed by proteomics for both H5N1-VN1203 and MERS-CoV infection. Importantly, epigenetic analysis suggested that DNA methylation, rather than histone modification, plays a crucial role in MERS-CoV–mediated antagonism of antigen-presentation gene expression; in contrast, H5N1-VN1203 likely utilizes a combination of epigenetic mechanisms to target antigen presentation. Together, the results indicate a common mechanism utilized by H5N1-VN1203 and MERS-CoV to modulate antigen presentation and the host adaptive immune response.

negative: Understanding the emerging coronavirus: what it means for health security and infection prevention

negative: Intranasal DNA Vaccine for Protection against Respiratory Infectious Diseases: The Delivery Perspectives Intranasal delivery of DNA vaccines has become a popular research area recently. It offers some distinguished advantages over parenteral and other routes of vaccine administration. Nasal mucosa as site of vaccine administration can stimulate respiratory mucosal immunity by interacting with the nasopharyngeal-associated lymphoid tissues (NALT). Different kinds of DNA vaccines are investigated to provide protection against respiratory infectious diseases including tuberculosis, coronavirus, influenza and respiratory syncytial virus (RSV) etc. DNA vaccines have several attractive development potential, such as producing cross-protection towards different virus subtypes, enabling the possibility of mass manufacture in a relatively short time and a better safety profile. The biggest obstacle to DNA vaccines is low immunogenicity. One of the approaches to enhance the efficacy of DNA vaccine is to improve DNA delivery efficiency. This review provides insight on the development of intranasal DNA vaccine for respiratory infections, with special attention paid to the strategies to improve the delivery of DNA vaccines using non-viral delivery agents.

negative: Influencia de la infección SARS-CoV-2 sobre enfermedades neurodegenerativas y neuropsiquiátricas: ¿una pandemia demorada? INTRODUCTION: SARS-CoV-2 was first detected in December 2019 in the Chinese city of Wuhan and has since spread across the world. At present, the virus has infected over 1.7 million people and caused over 100 000 deaths worldwide. Research is currently focused on understanding the acute infection and developing effective treatment strategies. In view of the magnitude of the epidemic, we conducted a speculative review of possible medium- and long-term neurological consequences of SARS-CoV-2 infection, with particular emphasis on neurodegenerative and neuropsychiatric diseases of neuroinflammatory origin, based on the available evidence on neurological symptoms of acute SARS-CoV-2 infection. DEVELOPMENT: We systematically reviewed the available evidence about the pathogenic mechanisms of SARS-CoV-2 infection, the immediate and lasting effects of the cytokine storm on the central nervous system, and the consequences of neuroinflammation for the central nervous system. CONCLUSIONS: SARS-CoV-2 is a neuroinvasive virus capable of triggering a cytokine storm, with persistent effects in specific populations. Although our hypothesis is highly speculative, the impact of SARS-CoV-2 infection on the onset and progression of neurodegenerative and neuropsychiatric diseases of neuroinflammatory origin should be regarded as the potential cause of a delayed pandemic that may have a major public health impact in the medium to long term. Cognitive and neuropsychological function should be closely monitored in COVID-19 survivors.

negative: Molecular advances in the cell biology of SARS-CoV and current disease prevention strategies In the aftermath of the SARS epidemic, there has been significant progress in understanding the molecular and cell biology of SARS-CoV. Some of the milestones are the availability of viral genome sequence, identification of the viral receptor, development of an infectious cDNA clone, and the identification of viral antigens that elicit neutralizing antibodies. However, there is still a large gap in our understanding of how SARS-CoV interacts with the host cell and the rapidly changing viral genome adds another variable to this equation. Now the SARS-CoV story has entered a new phase, a search for preventive strategies and a cure for the disease. This review highlights the progress made in identifying molecular aspects of SARS-CoV biology that is relevant in developing disease prevention strategies. Authors conclude that development of successful SARS-CoV vaccines and antivirals depends on the progress we make in these areas in the immediate future.

negative: Angiotensin receptor blockers as tentative SARS‐CoV‐2 therapeutics At the time of writing this commentary (February 2020), the coronavirus COVID‐19 epidemic has already resulted in more fatalities compared with the SARS and MERS coronavirus epidemics combined. Therapeutics that may assist to contain its rapid spread and reduce its high mortality rates are urgently needed. Developing vaccines against the SARS‐CoV‐2 virus may take many months. Moreover, vaccines based on viral‐encoded peptides may not be effective against future coronavirus epidemics, as virus mutations could make them futile. Indeed, new Influenza virus strains emerge every year, requiring new immunizations. A tentative suggestion based on existing therapeutics, which would likely be resistant to new coronavirus mutations, is to use available angiotensin receptor 1 (AT1R) blockers, such as losartan, as therapeutics for reducing the aggressiveness and mortality from SARS‐CoV‐2 virus infections. This idea is based on observations that the angiotensin‐converting enzyme 2 (ACE2) very likely serves as the binding site for SARS‐CoV‐2, the strain implicated in the current COVID‐19 epidemic, similarly to strain SARS‐CoV implicated in the 2002–2003 SARS epidemic. This commentary elaborates on the idea of considering AT1R blockers as tentative treatment for SARS‐CoV‐2 infections, and proposes a research direction based on datamining of clinical patient records for assessing its feasibility.

negative: Coronavirus: la emergencia geriátrica de 2020. Documento conjunto de la Sección de Cardiología Geriátrica de la Sociedad Española de Cardiología y la Sociedad Española de Geriatría y Gerontología Resumen La infección por SARS-CoV-2, denominada COVID-19 (Coronavirus Infectious Disease-19), es una enfermedad desconocida hasta diciembre de 2019 a la que nos enfrentamos en España desde el 31 de enero de 2020 —fecha del primer caso diagnosticado en nuestro país— y que ya ha causado la muerte de 7.340 personas (a 30 de marzo de 2020), sobre todo mayores. Es importante tener en cuenta que, dado que la información evoluciona con extremada rapidez en este campo, lo expuesto en el presente documento puede estar sujeto a modificaciones. La población de mayor edad es especialmente susceptible a la infección por COVID-19, así como a desarrollar criterios de gravedad. Este aumento de morbimortalidad en el paciente mayor se ha asociado tanto con las comorbilidades, especialmente la enfermedad cardiovascular, como con la situación de fragilidad, que conlleva una respuesta inmunológica más pobre. La situación actual, tanto por los países afectados como por el número de casos, constituye una pandemia y supone una emergencia sanitaria de primer nivel. Como España es uno de los países más envejecidos del mundo, la COVID-19 se ha convertido en una emergencia geriátrica. El presente documento se ha elaborado conjuntamente entre la Sección de Cardiología Geriátrica de la Sociedad Española de Cardiología y la Sociedad Española de Geriatría y Gerontología. Abstract SARS-CoV2 infection, also known as COVID-19 (coronavirus infectious disease-19), was first identified in December 2019. In Spain, the first case of this infection was diagnosed on 31 January, 2020 and, by 30 March 2020, has caused 7340 deaths, especially in the elderly. Due to the rapidly evolving situation regarding this disease, the data reported in this article may be subject to modifications. The older population are particularly susceptible to COVID-19 infection and to developing severe disease. The higher morbidity and mortality rates in older people have been associated with comorbidity, especially cardiovascular disease, and frailty, which weakens the immune response. Due to both the number of affected countries and the number of cases, the current situation constitutes an ongoing pandemic and a major health emergency. Because Spain has one of the largest older populations in the world, COVID-19 has emerged as a geriatric emergency. This document has been prepared jointly between the Geriatric Cardiology Section of the Spanish Society of Cardiology and the Spanish Society of Geriatrics and Gerontology.

negative: COVID-SGIS: A smart tool for dynamic monitoring and temporal forecasting of Covid-19 Objective The new kind of coronavirus SARS-Cov2 spread to countries in all continents in the World. The coronavirus disease 2019 (Covid-19) causes fever, cough, sore throat, and in severe cases shortness of breath and death. To evaluate strategies, it is necessary to forecast the number of cases and deaths, in order to aid the stakeholders in the process of making decisions against the disease. We propose a system for real-time forecast of the cumulative cases of Covid-19 in Brazil. Study Design Monitoring of all Brazilian cities using oficial information from the National Notification System, from March to May 2020, concentrated on Brazil.io databases. Training and evaluation of ARIMA and other machine learning algorithms for temporal forecasting using correlation indexes (Pearson's, Spearman's, and Kendall's) and RMSE(%). Validation from the relative errors of the following six days. Methods Our developed software, COVID-SGIS, captures information from the 26 states and the Distrito Federal at the Brazil.io database. From these data, ARIMA models are created for the accumulation of confirmed cases and death cases by Covid-19. Finally, six-day forecasts graphs are available for Brazil and for each of its federative units, separately, with a 95% CI. In addition to these predictions, the worst and best scenarios are also presented. Results ARIMA models were generated for Brazil and its 27 federative units. The states of Bahia, Maranhao, Piaui, Rio Grande do Norte, Amapa, Rondonia every day of the predictions were in the projection interval. The same happened to the states of Espirito Santo, Minas Gerais, Parana and Santa Catarina. In Brazil, the percentage error between the predicted values and the actual values varied between 2.56% and 6.50%. For the days when the forecasts outside the prediction interval, the percentage errors in relation to the worst case scenario were below 5%. The states of Bahia, Maranhao, Piaui, Rio Grande do Norte, Amapa, and Rondonia every day of the predictions were in the projection interval. The same happened to the states of Espirito Santo, Minas Gerais, Parana and Santa Catarina. Conclusion The proposed method for dynamic forecasting may be used to guide social policies and plan direct interventions in a robust, flexible and fast way. Since it is based on information from multiple databases, it can be adapted to the different realities, becoming an important tool to guide the course of politics and action against Covid-19 pandemic worldwide.

negative: Role of the inflammasome-related cytokines Il-1 and Il-18 during infection with murine coronavirus The inflammasome, a cytosolic protein complex that mediates the processing and secretion of pro-inflammatory cytokines, is one of the first responders during viral infection. The cytokines secreted following inflammasome activation, which include IL-1 and IL-18, regulate cells of both the innate and adaptive immune system, guiding the subsequent immune responses. In this study we used murine coronavirus, mouse hepatitis virus (MHV), infection of the central nervous system and liver to assess of the role of the inflammasome and its related cytokines on pathogenesis and host defense during viral infection. Mice lacking all inflammasome signaling due to the absence of caspase-1 and -11 were more vulnerable to infection, with poor survival and elevated viral replication compared to wild type mice. Mice lacking IL-1 signaling experienced elevated viral replication but similar survival compared to wild type controls. In the absence of IL-18, mice had elevated viral replication and poor survival, and this protective effect of IL-18 was found to be due to promotion of interferon gamma production in αβ T cells. These data suggest that inflammasome signaling is largely protective during murine coronavirus infection, in large part due to the pro-inflammatory effects of IL-18.

negative: Rapid isolation and profiling of a diverse panel of human monoclonal antibodies targeting the SARS-CoV-2 spike protein Antibodies are a principal determinant of immunity for most RNA viruses and have promise to reduce infection or disease during major epidemics. The novel coronavirus SARS-CoV-2 has caused a global pandemic with millions of infections and hundreds of thousands of deaths to date1,2. In response, we used a rapid antibody discovery platform to isolate hundreds of human monoclonal antibodies (mAbs) against the SARS-CoV-2 spike (S) protein. We stratify these mAbs into five major classes based on their reactivity to subdomains of S protein as well as their cross-reactivity to SARS-CoV. Many of these mAbs inhibit infection of authentic SARS-CoV-2 virus, with most neutralizing mAbs recognizing the receptor-binding domain (RBD) of S. This work defines sites of vulnerability on SARS-CoV-2 S and demonstrates the speed and robustness of new antibody discovery methodologies.

negative: How the SARS vaccine effort can learn from HIV—speeding towards the future, learning from the past A remarkable collaborative effort coordinated by the severe acute respiratory syndrome (SARS) team at WHO resulted in discovery of the etiologic agent of severe acute respiratory syndrome less than 2 months after the announcement of global alert. The development of a vaccine to prevent SARS should be pursued with the same urgency and cooperative spirit, as SARS is highly lethal and, if not controlled during the first few generations of transmission, is likely to become endemic in regions of the world where health-care infrastructure is underdeveloped and epidemiological control measures are weak. The scientific community already learned many important lessons from HIV vaccine development; these should be heeded. For example, consideration should be given to the development of a vaccine that will protect across regional strains of SARS, as the newly emergent coronavirus SARS-coronavirus (SARS-CoV) is proving to be variable and may be mutating in response to immune pressure. SARS-specific research reagents should also be collected and shared. These would include SARS peptides, adjuvants, DNA vaccine vectors and clinical grade viral vectors. Rapidly developing a collaborative approach to developing a SARS vaccine that will be both effective and safe is the only way to go. This article reviews parallels between HIV and SARS and proposes an approach that would accelerate the development of a SARS vaccine.

negative: BCG vaccine-induced protection from COVID-19 infection, wishful thinking or a game changer? A series of epidemiological explorations have suggested a negative association between national BCG vaccination policy and the prevalence and mortality of COVID-19. Nevertheless, these comparisons are difficult to validate due to broad differences between countries such as socioeconomic status, demographic structure, rural vs. urban settings, time of arrival of the pandemic, number of diagnostic tests and criteria for testing, and national control strategies to limit the spread of COVID-19. We review evidence for the potential biological basis of BCG cross-protection from severe COVID-19 and refine the epidemiological analysis to mitigate effects of potentially confounding factors (e.g., stage of the COVID-19 epidemic, development, rurality, population density and age structure). Results fail to confirm the null hypothesis of no-association between BCG vaccination and COVID-19 mortality, and suggest that BCG could have a protective effect. Nevertheless, the analyses are restricted to coarse-scale signals and should be considered with caution. BCG vaccination clinical trials are required to corroborate the patterns detected here and to establish causality between BCG vaccination and protection from severe COVID-19. Public health implications of a plausible BCG cross-protection from severe COVID-19 are discussed.

negative: Association of national Bacille Calmette-Guerin vaccination policy with COVID-19 epidemiology: an ecological study in 78 countries A possible association between national Bacille Calmette-Guerin (BCG) vaccination policy and lower COVID-19 incidence has been suggested in some preprint papers. Using publicly accessible databases, I explored associations of national BCG vaccination policy with COVID-19 epidemiology in 78 countries. Data collection was conducted from April 25 to May 5, 2020. I compared countries that have a current universal BCG vaccination policy (BCG countries), with countries that currently lack such a policy (non-BCG countries). The mixed effect model revealed national BCG policy decreases in the country-specific risk of death by COVID-19, correspond to odds ratio of 0.446 (95% confidence intervals 0.323 - 0.614, P =1x10-5). In BCG countries, the case increase rate was attenuated marginally by 25.4% (95% CI 3.0 to 42.7, P=0.029) as compared with those of the non-BCG countries. Although the protective mechanism of BCG vaccination against COVID-19 remains unknown, further laboratory and clinical research should be warranted.

negative: COVID-19 (Novel Coronavirus 2019) - recent trends The World Health Organization (WHO) has issued a warning that, although the 2019 novel coronavirus (COVID-19) from Wuhan City (China), is not pandemic, it should be contained to prevent the global spread. The COVID-19 virus was known earlier as 2019-nCoV. As of 12 February 2020, WHO reported 45,171 cases and 1115 deaths related to COVID-19. COVID-19 is similar to Severe Acute Respiratory Syndrome coronavirus (SARS-CoV) virus in its pathogenicity, clinical spectrum, and epidemiology. Comparison of the genome sequences of COVID-19, SARS-CoV, and Middle East Respiratory Syndrome coronavirus (MERS-CoV) showed that COVID-19 has a better sequence identity with SARS-CoV compared to MERS CoV. However, the amino acid sequence of COVID-19 differs from other coronaviruses specifically in the regions of 1ab polyprotein and surface glycoprotein or S-protein. Although several animals have been speculated to be a reservoir for COVID-19, no animal reservoir has been already confirmed. COVID-19 causes COVID-19 disease that has similar symptoms as SARS-CoV. Studies suggest that the human receptor for COVID-19 may be angiotensin-converting enzyme 2 (ACE2) receptor similar to that of SARS-CoV. The nucleocapsid (N) protein of COVID-19 has nearly 90% amino acid sequence identity with SARS-CoV. The N protein antibodies of SARS-CoV may cross react with COVID-19 but may not provide cross-immunity. In a similar fashion to SARS-CoV, the N protein of COVID-19 may play an important role in suppressing the RNA interference (RNAi) to overcome the host defense. This mini-review aims at investigating the most recent trend of COVID-19.

negative: COVID-19 in diabetic patients: related risks and specifics of management Abstract Diabetes is among the most frequently reported comorbidities in patients infected with COVID-19. According to current data, diabetic patients do not appear to be at increased risk of contracting SARS-CoV-2 compared to the general population. On the other hand, diabetes is a risk factor for developing severe and critical forms of COVID-19, the latter requiring admission to an intensive care unit and/or use of invasive mechanical ventilation, with high mortality rates. The characteristics of diabetic patients at risk for developing severe and critical forms of COVID-19, as well as the prognostic impact of diabetes on the course of COVID-19, are under current investigation. Obesity, the main risk factor for incident type 2 diabetes, is more common in patients with critical forms of COVID-19 requiring invasive mechanical ventilation. On the other hand, COVID-19 is usually associated with poor glycemic control and a higher risk of ketoacidosis in diabetic patients. There are currently no recommendations in favor of discontinuing antihypertensive medications that interact with the renin-angiotensin-aldosterone system. Metformin and SGLT2 inhibitors should be discontinued in patients with severe forms of COVID-19 owing to the risks of lactic acidosis and ketoacidosis. Finally, we advise for systematic screening for (pre)diabetes in patients with proven COVID-19 infection.

negative: Immunosuppression for hyperinflammation in COVID-19: a double-edged sword?

negative: The Role of Chest Imaging in Patient Management during the COVID-19 Pandemic: A Multinational Consensus Statement from the Fleischner Society Abstract With more than 900,000 confirmed cases worldwide and nearly 50,000 deaths during the first three months of 2020, the COVID-19 pandemic has emerged as an unprecedented healthcare crisis. The spread of COVID-19 has been heterogeneous, resulting in some regions having sporadic transmission and relatively few hospitalized patients with COVID-19 and others having community transmission that has led to overwhelming numbers of severe cases. For these regions, healthcare delivery has been disrupted and compromised by critical resource constraints in diagnostic testing, hospital beds, ventilators, and healthcare workers who have fallen ill to the virus exacerbated by shortages of personal protective equipment. While mild cases mimic common upper respiratory viral infections, respiratory dysfunction becomes the principal source of morbidity and mortality as the disease advances. Thoracic imaging with chest radiography (CXR) and computed tomography (CT) are key tools for pulmonary disease diagnosis and management, but their role in the management of COVID-19 has not been considered within the multivariable context of the severity of respiratory disease, pre-test probability, risk factors for disease progression, and critical resource constraints. To address this deficit, a multidisciplinary panel comprised principally of radiologists and pulmonologists from 10 countries with experience managing COVID-19 patients across a spectrum of healthcare environments evaluated the utility of imaging within three scenarios representing varying risk factors, community conditions, and resource constraints. Fourteen key questions, corresponding to 11 decision points within the three scenarios and three additional clinical situations, were rated by the panel based upon the anticipated value of the information that thoracic imaging would be expected to provide. The results were aggregated, resulting in five main and three additional recommendations intended to guide medical practitioners in the use of CXR and CT in the management of COVID-19.

negative: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and coronavirus disease-2019 (COVID-19): The epidemic and the challenges The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2; previously provisionally named 2019 novel coronavirus or 2019-nCoV) disease (COVID-19) in China at the end of 2019 has caused a large global outbreak and is a major public health issue. As of 11 February 2020, data from the World Health Organization (WHO) have shown that more than 43 000 confirmed cases have been identified in 28 countries/regions, with >99% of cases being detected in China. On 30 January 2020, the WHO declared COVID-19 as the sixth public health emergency of international concern. SARS-CoV-2 is closely related to two bat-derived severe acute respiratory syndrome-like coronaviruses, bat-SL-CoVZC45 and bat-SL-CoVZXC21. It is spread by human-to-human transmission via droplets or direct contact, and infection has been estimated to have mean incubation period of 6.4 days and a basic reproduction number of 2.24–3.58. Among patients with pneumonia caused by SARS-CoV-2 (novel coronavirus pneumonia or Wuhan pneumonia), fever was the most common symptom, followed by cough. Bilateral lung involvement with ground-glass opacity was the most common finding from computed tomography images of the chest. The one case of SARS-CoV-2 pneumonia in the USA is responding well to remdesivir, which is now undergoing a clinical trial in China. Currently, controlling infection to prevent the spread of SARS-CoV-2 is the primary intervention being used. However, public health authorities should keep monitoring the situation closely, as the more we can learn about this novel virus and its associated outbreak, the better we can respond.

negative: Maternal antibody to infectious bronchitis virus: its role in protection against infection and development of active immunity to vaccine Abstract Chicks hatched with high levels of maternal antibody had excellent protection (>95%) against infectious bronchitis virus (IBV) challenge at 1 day of age, but not at 7 days (<30%). This protection significantly (P<0.05) correlated with levels of local respiratory antibody and not with serum antibody. A high percentage of both maternal antibody-positive (Mab+) and maternal antibody-negative (Mab−) chicks failed to produce IBV antibody when vaccinated at 1 day of age by the intraocular route. In addition, Mab+ chickens had a weaker virus-neutralizing antibody response to a second IBV vaccination compared to Mab− birds (P<0.05). Mab+ chicks experienced a more rapid decline (P<0.01) in maternal antibody after 1-day-of-age vaccination compared to their unvaccinated counterparts. A monoclonal antibody-based blocking ELISA that measured antibody levels specific to S1 glycoprotein of IBV correlated well with virus-neutralizing antibody titers.

negative: Infectious Bronchitis Virus Population Structure Defines Immune Response and Protection. A commercial Arkansas (Ark) Delmarva Poultry Industry (DPI)-type vaccine and a more homogeneous population of that vaccine obtained previously through adaptation to chicken embryo kidney (CEK) cells (CEK-ArkDPI) were used as a model to further understand the impact of population genetic structure on generation of immune responses and protection. In a first experiment, vaccinated chickens were challenged with an IBV Ark99-type virulent strain (AL/4614/98). Despite extensive sequence similarity between the vaccines, the more heterogeneous commercial ArkDPI was more efficient at reducing viral loads in challenged chickens, while respiratory signs and tracheal lesions were reduced similarly by either vaccine. A distinct subpopulation of the Ark challenge virus showing asparagine at S1 position 56 was consistently negatively selected by immune pressure originating from vaccination with either vaccine. Antibody levels and antibody avidity to Ark-type S1 protein were greater in CEK-ArkDPI-vaccinated chickens compared to chickens vaccinated with the more diverse commercial ArkDPI vaccine. Synchronous replication of a homogeneous virus population likely elicits clonal expansion and affinity maturation of a greater number of responding B cells compared to a diverse virus population continuously changing its proportion of phenotypes during replication. The results of a second experiment showed that during initial vaccine virus replication (24 and 48 hr postvaccination), the virus population showing increased diversity (commercial ArkDPI) achieved higher concentrations of IBV RNA in the trachea compared to the more homogenous virus. mRNA expression of genes associated with innate immune responses in the trachea 48 hr postvaccination generally showed greater upregulation in chickens vaccinated with the heterogeneous commercial ArkDPI vaccine compared to the CEK-adapted virus. The greater upregulation of these genes is likely associated with higher virus replication achieved by the heterogeneous commercial vaccine. Thus, while the adaptive antibody response was favored by the more homogenous structure of the CEK-ArkDPI vaccine population (higher antibody levels and antibody avidity), the innate immune response was favored by the more diverse viral population of the commercial ArkDPI. We confirmed previous results that distinct subpopulations in wild Ark challenge virus become selected by immune pressure originating from vaccination, and we concluded that the population structure of IBV vaccines impacts innate immune response, antibody avidity, and protection.

negative: Investigation into SARS-CoV-2 Resistance of Compounds in Garlic Essential Oil [Image: see text] Eighteen active substances, including 17 organosulfur compounds found in garlic essential oil (T), were identified by GC–MS analysis. For the first time, using the molecular docking technique, we report the inhibitory effect of the considered compounds on the host receptor angiotensin-converting enzyme 2 (ACE2) protein in the human body that leads to a crucial foundation about coronavirus resistance of individual compounds on the main protease (PDB6LU7) protein of SARS-CoV-2. The results show that the 17 organosulfur compounds, accounting for 99.4% contents of the garlic essential oil, have strong interactions with the amino acids of the ACE2 protein and the main protease PDB6LU7 of SARS-CoV-2. The strongest anticoronavirus activity is expressed in allyl disulfide and allyl trisulfide, which account for the highest content in the garlic essential oil (51.3%). Interestingly, docking results indicate the synergistic interactions of the 17 substances, which exhibit good inhibition of the ACE2 and PDB6LU7 proteins. The results suggest that the garlic essential oil is a valuable natural antivirus source, which contributes to preventing the invasion of coronavirus into the human body.

negative: Practical recommendations for the management of diabetes in patients with COVID-19 Summary Diabetes is one of the most important comorbidities linked to the severity of all three known human pathogenic coronavirus infections, including severe acute respiratory syndrome coronavirus 2. Patients with diabetes have an increased risk of severe complications including Adult Respiratory Distress Syndrome and multi-organ failure. Depending on the global region, 20–50% of patients in the coronavirus disease 2019 (COVID-19) pandemic had diabetes. Given the importance of the link between COVID-19 and diabetes, we have formed an international panel of experts in the field of diabetes and endocrinology to provide some guidance and practical recommendations for the management of diabetes during the pandemic. We aim to briefly provide insight into potential mechanistic links between the novel coronavirus infection and diabetes, present practical management recommendations, and elaborate on the differential needs of several patient groups.

negative: Acute asthma management during SARS-CoV2-pandemic 2020 Abstract Background The current COVID-19 pandemic has changed many medical practices in order to provide additional protection to both our patients and our healthcare providers. In many cases this includes seeing patients through electronic means such as telehealth or telephone rather than seeing them in person. Asthma exacerbations cannot always be treated in this way. Problem Current emergency unit asthma guidelines recommend bronchodilators be administered by metered dose inhaler (MDI) and spacer for mild-moderate asthma and include it as a choice even in severe asthma, but many emergency units continue to prefer nebulised therapy for patients who urgently require beta-agonists. The utilization of nebulised therapy potentially increases the risk of aerosolization of the coronavirus. Since nosocomial transmission of respiratory pathogens is a major threat in the context of the SARS-CoV-2 pandemic, use of nebulised therapy is of even greater concern due to the potential increased risk of infection spread to nearby patients and health-care workers. Practical implications We propose a risk stratification plan that aims to avoid nebulised therapy, when possible, by providing an algorithm to help better delineate those who require nebulised therapy. Protocols that include strategies to allow flexibility in using MDIs rather than nebulisers in all but the most severe patients should help mitigate this risk of aerosolised infection transmission to patients and health care providers. Furthermore, expedient treatment of patients with high dose MDI therapy augmented with more rapid initiation of systemic therapy may help ensure patients are less likely to deteriorate to the stage where nebulisers are required.

negative: No SARS-CoV-2 in expressed prostatic secretion of patients with coronavirus disease 2019: a descriptive multicentre study in China Abstract Purpose: The aim of the present study was to assess whether SARS-CoV-2 can be detected in the expressed prostatic secretion (EPS) of patients with corona virus disease 2019 (COVID-19). Methods: 18 cases of COVID-19, and 5 suspected cases, were selected from three medical centers to detect the RNA expression of SARS-CoV-2 in their EPS with RT-PCR. Results: Results were negative in all EPS samples for SARS-CoV-2 of suspected and confirmed patients. Conclusions: No SARS-CoV-2 was expressed in EPS of patients with COVID-19.

negative: Epitope specificity of protective lactogenic immunity against swine transmissible gastroenteritis virus. The epitope specificity of the protective immune response against swine transmissible gastroenteritis (TGE) has been investigated by using circulating and secretory antibodies. This study was carried out with sows vaccinated with TGEV or the antigenically related porcine respiratory coronavirus (PRCV). TGEV vaccination of sows resulted in greater lactogenic protection of suckling piglets against TGEV challenge and a higher secretory immune response than PRCV vaccination did. These differences in the immune response were conditioned by the route of antigen presentation as a result of the different tropism of each virus. Epitopes on S protein, and in particular those contained in its antigenic site. A, were more immunogenic than epitopes on N and M proteins in both groups of vaccinated sows, as determined by a competitive radioimmunoassay. Minor differences in antibody response against the previously defined antigenic subsites Aa, Ab, and Ac were also detected, with subsite Ab being the most antigenic in both TGEV- and PRCV-immune sows. These findings suggest that antigenic site A on S protein, involved in virus neutralization, is the immunodominant site in pregnant sows that confer lactogenic protection. They also validate, in experiments with secretory antibodies, the antigenic maps made with murine monoclonal antibodies. Therefore, this antigenic site should be considered for vaccine or diagnostic development.

negative: Screening of Natural Extracts for Inhibitors against Japanese Encephalitis Virus Infection The mosquito-borne Japanese encephalitis virus (JEV) causes serious illness worldwide that is associated with high morbidity and mortality. Currently, there are no effective drugs approved for the treatment of JEV infection. Drug-repurposing screening is an alternative approach to discover potential antiviral agents. In this study, high-content screening (HCS) of a natural extracts library was performed, and two hit FDA-approved Na(+)/K(+)-ATPase inhibitors, ouabain and digoxin, were identified as having robust efficiency against JEV infection with the selectivity indexes over 1,000. The results indicated that ouabain and digoxin blocked the JEV infection at the replication stage by targeting the Na(+)/K(+)-ATPase. Furthermore, it was proven that ouabain significantly reduced the morbidity and mortality caused by JEV in a BALB/c mouse model. This work demonstrated that Na(+)/K(+)-ATPase could serve as the target of treatment of JEV infection, and ouabain has the potential to be developed as an effective anti-JEV drug.

negative: Emerging SARS-CoV-2 mutation hot spots include a novel RNA-dependent-RNA polymerase variant BACKGROUND: SARS-CoV-2 is a RNA coronavirus responsible for the pandemic of the Severe Acute Respiratory Syndrome (COVID-19). RNA viruses are characterized by a high mutation rate, up to a million times higher than that of their hosts. Virus mutagenic capability depends upon several factors, including the fidelity of viral enzymes that replicate nucleic acids, as SARS-CoV-2 RNA dependent RNA polymerase (RdRp). Mutation rate drives viral evolution and genome variability, thereby enabling viruses to escape host immunity and to develop drug resistance. METHODS: We analyzed 220 genomic sequences from the GISAID database derived from patients infected by SARS-CoV-2 worldwide from December 2019 to mid-March 2020. SARS-CoV-2 reference genome was obtained from the GenBank database. Genomes alignment was performed using Clustal Omega. Mann-Whitney and Fisher-Exact tests were used to assess statistical significance. RESULTS: We characterized 8 novel recurrent mutations of SARS-CoV-2, located at positions 1397, 2891, 14408, 17746, 17857, 18060, 23403 and 28881. Mutations in 2891, 3036, 14408, 23403 and 28881 positions are predominantly observed in Europe, whereas those located at positions 17746, 17857 and 18060 are exclusively present in North America. We noticed for the first time a silent mutation in RdRp gene in England (UK) on February 9th, 2020 while a different mutation in RdRp changing its amino acid composition emerged on February 20th, 2020 in Italy (Lombardy). Viruses with RdRp mutation have a median of 3 point mutations [range: 2-5], otherwise they have a median of 1 mutation [range: 0-3] (p value < 0.001). CONCLUSIONS: These findings suggest that the virus is evolving and European, North American and Asian strains might coexist, each of them characterized by a different mutation pattern. The contribution of the mutated RdRp to this phenomenon needs to be investigated. To date, several drugs targeting RdRp enzymes are being employed for SARS-CoV-2 infection treatment. Some of them have a predicted binding moiety in a SARS-CoV-2 RdRp hydrophobic cleft, which is adjacent to the 14408 mutation we identified. Consequently, it is important to study and characterize SARS-CoV-2 RdRp mutation in order to assess possible drug-resistance viral phenotypes. It is also important to recognize whether the presence of some mutations might correlate with different SARS-CoV-2 mortality rates.

negative: Investigating a safe ventilation rate for the prevention of indoor SARS transmission: An attempt based on a simulation approach This paper identifies the “safe ventilation rate” for eliminating airborne viral infection and preventing cross-infection of severe acute respiratory syndrome (SARS) in a hospital-based setting. We used simulation approaches to reproduce three actual cases where groups of hospital occupants reported to be either infected or not infected when SARS patients were hospitalized in nearby rooms. Simulations using both computational fluid dynamics (CFD) and multi-zone models were carried out to understand the dilution level of SARS virus-laden aerosols during these scenarios. We also conducted a series of measurements to validate the simulations. The ventilation rates (dilution level) for infection and non-infection were determined based on these scenarios. The safe ventilation rate for eliminating airborne viral infection is to dilute the air emitted from a SARS patient by 10000 times with clean air. Dilution at lower volumes, specifically 1000 times, is insufficient for protecting non-infected people from SARS exposure and the risk of infection is very high. This study provides a methodology for investigating the necessary ventilation rate from an engineering viewpoint.

negative: Extremely low exposure of a community to severe acute respiratory syndrome coronavirus: false seropositivity due to use of bacterially derived antigens. Estimates of seropositivity to a new infectious agent in a community are useful to public health. For severe acute respiratory syndrome (SARS), the figures are conflicting. Herein, we screened 12,000 people in a community stricken by SARS 10 months previously and found 53 individuals (0.44%) who had immunoglobulin G antibodies to the SARS coronavirus (SARS-CoV) nucleocapsid (N) produced in bacteria. However, only seven of these (group 1) had sera which also reacted with the native N antigen expressed in SARS-CoV-infected Vero cells, N-transfected 293T cells, and tissues of infected SARS patients. Of these, six individuals had had SARS previously. The remaining person, as well as the 46 other individuals (group 2), were healthy and had no history of SARS. Group 1 antibodies recognized epitopes located slightly differently in N from those of group 2 antibodies, and a mouse hybridoma antibody resembling the former type was generated. Unusually, group 2 antibodies appeared to recognize cross-reactive bacterial epitopes that presumably were posttranslationally modified in eukaryotes and hence were probably not induced by SARS-CoV or related coronaviruses but rather by bacteria. The N antigen is thus highly unique. The extremely low rate (0.008%) of asymptomatic SARS infection found attests to the high virulence of the SARS-CoV virus.

negative: Combating Canine ‘Visiting Cards’: Public Hygiene and the Management of Dog Mess in Paris since the 1920s This article examines the history of dog mess in Paris, from its ‘discovery’ in the late 1920s to the management regime of the early twenty-first century. Mayor Jacques Chirac’s anti-excrement campaigns in the 1980s are a particular focus. Situating the meaning and management of dog mess within histories of public hygiene and disgust, and mobilising insights from work on public hygiene, biopolitics and governmentality, this article shows how Chirac’s attempt to produce self-regulating and responsible dog owners through education failed to persuade them to overcome their disgust at their pets’ excrement. Fining alongside education proved a more effective management strategy. The history of dog mess in Paris highlights the biopolitical problems raised by animal excrement decades after the apogee of the public hygiene movement, and shows how human–animal partnerships expose the limits of governmentality approaches to public hygiene and neo-liberal urban governance.

negative: Towards a Coronavirus-Based HIV Multigene Vaccine Human immunodeficiency virus (HIV) infection represents one of the major health threats in the developing world. The costly treatment of infected individuals with multiple highly efficient anti-HIV drugs is only affordable in industrialized countries. Thus, an efficient vaccination strategy is required to prevent the further spread of the infection. The molecular biology of coronaviruses and particular features of the human coronavirus 229E (HCoV 229E) indicate that HCoV 229E-based vaccine vectors can become a new class of highly efficient vaccines. First, the receptor of HCoV 229E, human aminopeptidase N (hAPN or CD13) is expressed mainly on human dendritic cells (DCs) and macrophages indicating that targeting of HCoV 229E-based vectors to professional antigen presenting cells can be achieved by receptor-mediated transduction. Second, HCoV 229E structural genes can be replaced by multiple transcriptional units encoding various antigens. These virus-like particles (VLPs) containing HCoV 229E-based vector RNA have the ability to transduce human DCs and to mediate heterologous gene expression in these cells. Finally, coronavirus infections are associated with mainly respiratory and enteric diseases, and natural transmission of coronaviruses occurs via mucosal surfaces. In humans, HCoV 229E causes common cold by infecting the upper respiratory tract. HCoV 229E infections are mainly encountered in children and re-infection occurs frequently in adults. It is thus most likely that pre-existing immunity against HCoV 229E will not significantly impact on the vaccination efficiency if HCoV 229E-based vectors are used in humans.

negative: Priming with a DNA vaccine and boosting with an inactivated vaccine enhance the immune response against infectious bronchitis virus Abstract The methods of repeated immunization with inactivated vaccines have been used widely to increase antibody protection against infectious bronchitis virus (IBV). However, compared with DNA vaccines, these methods usually induce poor cellular responses. In the present study, specific pathogen-free (SPF) chickens were immunized intramuscularly with a DNA vaccine carrying the main IBV structural genes (pVAX1-S1, pVAX1-M, and pVAX1-N, respectively) and boosted with the IBV M41 strain inactivated vaccine to assess whether such a new strategy could enhance the immune responses against IBV. The protection efficacy of the DNA vaccine carrying different structural genes for priming was evaluated further. The chickens were immunized primely on day 7 and boosted 2 weeks later. After that, distribution of the DNA vaccine in vivo, the percentage of CD4+CD3+ and CD8+CD3+ subgroups of peripheral blood T-lymphocytes, and the specific IgG and virus neutralizing antibodies were measured. Chickens were then challenged by the nasal–ocular route with the IBV M41 strain 4 weeks after booster immunization. The results demonstrated that priming with a DNA vaccine encoding nucleocapsid protein (pVAX1-N) and boosting with the inactivated IBV vaccine led to the dramatic augmentation of humoral and cellular responses, and provided up to 86.7% rate of immune protection, providing an effective approach to protect chickens from IBV.

negative: Compassionate use of others’ immunity — understanding gut microbiome in Covid-19

negative: Still puzzling questions in immunology (infection and immunity)

negative: El síndrome respiratorio agudo grave: primera pandemia del siglo XXI

negative: Metronomic oral vinorelbine and lung cancer therapy during the COVID 19 pandemic: a single-center experience • Intravenous vinorelbine is a standard treatment for advanced NSCLC; • Oral vinorelbine is equally effective as compared to intravenous vinorelbine; • Metronomic oral formulation of vinorelbine is a safe and active treatment for advanced NSCLC; • No established treatment is a “gold standard” during COVID19 era; • Metronomic oral vinorelbine permitted to carry on active treatment during COVID Emergency; • Metronomic oral vinorelbine reduce side effects and hospital visits to lung cancer patients; • Management of lung cancer patients may be improved by metronomic oral vinorelbine.

negative: Recombinant Live Vaccines to Protect Against the Severe Acute Respiratory Syndrome Coronavirus The severe acute respiratory syndrome (SARS) coronavirus (CoV) was identified as the etiological agent of an acute respiratory disease causing atypical pneumonia and diarrhea with high mortality. Different types of SARS-CoV vaccines, including nonreplicative and vectored vaccines, have been developed. Administration of these vaccines to animal model systems has shown promise for the generation of efficacious and safe vaccines. Nevertheless, the identification of side effects, preferentially in the elderly animal models, indicates the need to develop novel vaccines that should be tested in improved animal model systems. Live attenuated viruses have generally proven to be the most effective vaccines against viral infections. A limited number of SARS-CoV attenuating modifications have been described, including mutations, and partial or complete gene deletions affecting the replicase, like the nonstructural proteins (nsp1 or nsp2), or the structural genes, and drastic changes in the sequences that regulate the expression of viral subgenomic mRNAs. A promising vaccine candidate developed in our laboratory was based on deletion of the envelope E gene alone, or in combination with the removal of six additional genes nonessential for virus replication. Viruses lacking E protein were attenuated, grew in the lung, and provided homologous and heterologous protection. Improvements of this vaccine candidate have been directed toward increasing virus titers using the power of viruses with mutator phenotypes, while maintaining the attenuated phenotype. The safety of the live SARS-CoV vaccines is being increased by the insertion of complementary modifications in genes nsp1, nsp2, and 3a, by gene scrambling to prevent the rescue of a virulent phenotype by recombination or remodeling of vaccine genomes based on codon deoptimization using synthetic biology. The newly generated vaccine candidates are very promising, but need to be evaluated in animal model systems that include young and aged animals.

negative: COVID-19 infection: Origin, transmission, and characteristics of human coronaviruses The coronavirus disease 19 (COVID-19) is a highly transmittable and pathogenic viral infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which emerged in Wuhan, China and spread around the world. Genomic analysis revealed that SARS-CoV-2 is phylogenetically related to severe acute respiratory syndrome-like (SARS-like) bat viruses, therefore bats could be the possible primary reservoir. The intermediate source of origin and transfer to humans is not known, however, the rapid human to human transfer has been confirmed widely. There is no clinically approved antiviral drug or vaccine available to be used against COVID-19. However, few broad-spectrum antiviral drugs have been evaluated against COVID-19 in clinical trials, resulted in clinical recovery. In the current review, we summarize and comparatively analyze the emergence and pathogenicity of COVID-19 infection and previous human coronaviruses severe acute respiratory syndrome coronavirus (SARS-CoV) and middle east respiratory syndrome coronavirus (MERS-CoV). We also discuss the approaches for developing effective vaccines and therapeutic combinations to cope with this viral outbreak.

negative: Structural basis of SARS-CoV-2 3CLpro and anti-COVID-19 drug discovery from medicinal plants † Abstract The recent outbreak of coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 in December 2019 raised global health concerns. The viral 3-chymotrypsin-like cysteine protease (3CLpro) enzyme controls coronavirus replication and is essential for its life cycle. 3CLpro is a proven drug discovery target in the case of severe acute respiratory syndrome coronavirus (SARS-CoV) and middle east respiratory syndrome coronavirus (MERS-CoV). Recent studies revealed that the genome sequence of SARS-CoV-2 is very similar to that of SARS-CoV. Therefore, herein, we analysed the 3CLpro sequence, constructed its 3D homology model, and screened it against a medicinal plant library containing 32,297 potential anti-viral phytochemicals/traditional Chinese medicinal compounds. Our analyses revealed that the top nine hits might serve as potential anti- SARS-CoV-2 lead molecules for further optimisation and drug development process to combat COVID-19.

negative: Differential COVID-19-attributable mortality and BCG vaccine use in countries While mortality attributable to COVID-19 has devastated global health systems and economies, striking regional differences have been observed. The Bacille Calmette Guerin (BCG) vaccine has previously been shown to have non-specific protective effects on infections, as well as long-term efficacy against tuberculosis. Using publicly available data we built a simple log-linear regression model to assess the association of BCG use and COVID-19-attributable mortality per 1 million population after adjusting for confounders including country economic status (GDP per capita), and proportion of elderly among the population. The timing of country entry into the pandemic epidemiological trajectory was aligned by plotting time since the 100th reported case. Countries with economies classified as lower-middle-income, upper-middle-income and high-income countries (LMIC, UMIC, HIC) had median crude COVID-19 log-mortality of 0.4 (Interquartile Range (IQR) 0.1, 0.4), 0.7 (IQR 0.2, 2.2) and 5.5 (IQR 1.6, 13.9), respectively. COVID-19-attributable mortality among BCG-using countries was 5.8 times lower [95% CI 1.8-19.0] than in non BCG-using countries. Notwithstanding limitations due to testing constraints in LMICs, case ascertainment bias and a plausible rise of cases as countries progress along the epidemiological trajectory, these analyses provide intriguing observations that urgently warrant mobilization of resources for prospective randomized interventional studies and institution of systematic disease surveillance, particularly in LMICs.

negative: Importance of early precautionary actions in avoiding the spread of COVID-19: Saudi Arabia as an Example Late in 2019, several cases of new strains of coronavirus were reported in China. This new strain was later officially named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by the World Health Organization (WHO). This new virus (SARS-CoV2-) mainly affects the respiratory system and causes coronavirus disease 2019 (COVID-19). The first case of COVID-19 was reported to the WHO on December 31(st), 2019, and the virus has spread dramatically in many countries worldwide. On March 11(th), 2020, the WHO declared that COVID-19 and had affected most of the world, and many cases of death were linked to COVID-19. Unfortunately, there is no available treatment for COVID-19, and there is no available vaccine against SARS-CoV-2. Thus, prevention methods are the only way to limit the spread of the virus. Preventive actions have been taken by many countries, such as travel bans, closing borders and working from home. Saudi Arabia was one of the countries that took very early precautionary actions in the belief that these actions are the best way to fight the virus. Therefore, we present the actions that were taken by the Kingdom of Saudi Arabia to fight the new virus pandemic.

negative: SARS CORONAVIRUS AND INNATE IMMUNITY The emergence of the highly pathogenic SARS coronavirus (SARS-CoV) has reignited interest in coronavirus biology and pathogenesis. An emerging theme in coronavirus pathogenesis is that the interaction between specific viral genes and the host immune system, specifically the innate immune system, functions as a key determinant in regulating virulence and disease outcomes. Using SARS-CoV as a model, we will review the current knowledge of the interplay between coronavirus infection and the host innate immune system in vivo, and then discuss the mechanisms by which specific gene products antagonize the host innate immune response in cell culture models. Our data suggests that the SARS-CoV uses specific strategies to evade and antagonize the sensing and signaling arms of the interferon pathway. We summarize by identifying future points of consideration that will contribute greatly to our understanding of the molecular mechanisms governing coronavirus pathogenesis and virulence, and the development of severe disease in humans and animals.

negative: Successful vaccination strategies that protect aged mice from lethal challenge from influenza virus and heterologous severe acute respiratory syndrome coronavirus. Newly emerging viruses often circulate as a heterogeneous swarm in wild animal reservoirs prior to their emergence in humans, and their antigenic identities are often unknown until an outbreak situation. The newly emerging severe acute respiratory syndrome coronavirus (SARS-CoV) and reemerging influenza virus cause disproportionate disease in the aged, who are also notoriously difficult to successfully vaccinate, likely due to immunosenescence. To protect against future emerging strains, vaccine platforms should induce broad cross-reactive immunity that is sufficient to protect from homologous and heterologous challenge in all ages. From initial studies, we hypothesized that attenuated Venezuelan equine encephalitis virus (VEE) replicon particle (VRP) vaccine glycoproteins mediated vaccine failure in the aged. We then compared the efficacies of vaccines bearing attenuated (VRP(3014)) or wild-type VEE glycoproteins (VRP(3000)) in young and aged mice within novel models of severe SARS-CoV pathogenesis. Aged animals receiving VRP(3000)-based vaccines were protected from SARS-CoV disease, while animals receiving the VRP(3014)-based vaccines were not. The superior protection for the aged observed with VRP(3000)-based vaccines was confirmed in a lethal influenza virus challenge model. While the VRP(3000) vaccine's immune responses in the aged were sufficient to protect against lethal homologous and heterologous challenge, our data suggest that innate defects within the VRP(3014) platform mediate vaccine failure. Exploration into the mechanism(s) of successful vaccination in the immunosenescent should aid in the development of successful vaccine strategies for other viral diseases disproportionately affecting the elderly, like West Nile virus, influenza virus, norovirus, or other emerging viruses of the future.

negative: Machine intelligence design of 2019-nCoV drugs Wuhan coronavirus, called 2019-nCoV, is a newly emerged virus that infected more than 9692 people and leads to more than 213 fatalities by January 30, 2020. Currently, there is no effective treatment for this epidemic. However, the viral protease of a coronavirus is well-known to be essential for its replication and thus is an effective drug target. Fortunately, the sequence identity of the 2019-nCoV protease and that of severe-acute respiratory syndrome virus (SARS-CoV) is as high as 96.1%. We show that the protease inhibitor binding sites of 2019-nCoV and SARS-CoV are almost identical, which means all potential anti-SARS-CoV chemotherapies are also potential 2019-nCoV drugs. Here, we report a family of potential 2019-nCoV drugs generated by a machine intelligence-based generative network complex (GNC). The potential effectiveness of treating 2019-nCoV by using some existing HIV drugs is also analyzed.

negative: Control of influenza virus infection by immunity to conserved viral features. Influenza has circulated among humans for centuries and kills more people than many newly emerging diseases. The present methods for control of influenza are not adequate, especially for dealing with a pandemic. In the face of a rapidly spreading outbreak, a race to isolate the virus and prepare a vaccine would probably not succeed in time to avoid great losses. Thus, additional anti-infection strategies are needed. Broad cross-protection against widely divergent influenza A subtypes is readily achieved in animals by several means of immunization. How does cross-protection work in animals, and can we apply what we have learned about it to induce broad cross-protection in humans?

negative: Composition and divergence of coronavirus spike proteins and host ACE2 receptors predict potential intermediate hosts of SARS‐CoV‐2 From the beginning of 2002 and 2012, severe respiratory syndrome coronavirus (SARS‐CoV) and Middle East respiratory syndrome coronavirus (MERS‐CoV) crossed the species barriers to infect humans, causing thousands of infections and hundreds of deaths, respectively. Currently, a novel coronavirus (SARS‐CoV‐2), which has become the cause of the outbreak of Coronavirus Disease 2019 (COVID‐19), was discovered. Until 18 February 2020, there were 72 533 confirmed COVID‐19 cases (including 10 644 severe cases) and 1872 deaths in China. SARS‐CoV‐2 is spreading among the public and causing substantial burden due to its human‐to‐human transmission. However, the intermediate host of SARS‐CoV‐2 is still unclear. Finding the possible intermediate host of SARS‐CoV‐2 is imperative to prevent further spread of the epidemic. In this study, we used systematic comparison and analysis to predict the interaction between the receptor‐binding domain (RBD) of coronavirus spike protein and the host receptor, angiotensin‐converting enzyme 2 (ACE2). The interaction between the key amino acids of S protein RBD and ACE2 indicated that, other than pangolins and snakes, as previously suggested, turtles (Chrysemys picta bellii, Chelonia mydas, and Pelodiscus sinensis) may act as the potential intermediate hosts transmitting SARS‐CoV‐2 to humans.

negative: Modeling Return of the Epidemic: Impact of Population Structure, Asymptomatic Infection, Case Importation and Personal Contacts Background: Proactive interventions have halted the pandemic of coronavirus infected disease in some regions. However, without reaching herd immunity, the return of epidemic is possible. We investigate the impact of population structure, case importation, asymptomatic cases, and the number of contacts on a possible second wave of epidemic through mathematical modelling. Methods: we built a modified Susceptible-exposed-Infectious-Removed (SEIR) model with parameters mirroring those of the COVID-19 pandemic and reported simulated characteristics of epidemics for incidence, hospitalizations and deaths under different scenarios. Results: A larger percent of old people leads to higher number of hospitalizations, while a large percent of prior infection will effectively curb the epidemic. The number of imported cases and the speed of importation have small impact on the epidemic progression. However, a higher percent of asymptomatic cases slows the epidemic down and reduces the number of hospitalizations and deaths at the epidemic peak. Finally, reducing the number of contacts among young people alone has moderate effects on themselves, but little effects on the old population. However, reducing the number of contacts among old people alone can mitigate the epidemic significantly in both groups, even though young people remain active within themselves. Conclusion: Reducing the number of contacts among high risk populations alone can mitigate the burden of epidemic in the whole society. Interventions targeting high risk groups may be more effective in containing or mitigating the epidemic.

negative: The use of anti-inflammatory drugs in the treatment of people with severe coronavirus disease 2019 (COVID-19): The Perspectives of clinical immunologists from China Abstract The pandemic outbreak of coronavirus disease 2019 (COVID-19) is rapidly spreading all over the world. Reports from China showed that about 20% of patients developed severe disease, resulting in a fatality of 4%. In the past two months, we clinical immunologists participated in multi-rounds of MDT (multidiscipline team) discussion on the anti-inflammation management of critical COVID-19 patients, with our colleagues dispatched from Chinese leading PUMC Hospital to Wuhan to admit and treat the most severe patients. Here, from the perspective of clinical immunologists, we will discuss the clinical and immunological characteristics of severe patients, and summarize the current evidence and share our experience in anti-inflammation treatment, including glucocorticoids, IL-6 antagonist, JAK inhibitors and choloroquine/hydrocholoroquine, of patients with severe COVID-19 that may have an impaired immune system.

negative: Middle East respiratory syndrome coronavirus neutralising serum antibodies in dromedary camels: a comparative serological study Summary Background A new betacoronavirus—Middle East respiratory syndrome coronavirus (MERS-CoV)—has been identified in patients with severe acute respiratory infection. Although related viruses infect bats, molecular clock analyses have been unable to identify direct ancestors of MERS-CoV. Anecdotal exposure histories suggest that patients had been in contact with dromedary camels or goats. We investigated possible animal reservoirs of MERS-CoV by assessing specific serum antibodies in livestock. Methods We took sera from animals in the Middle East (Oman) and from elsewhere (Spain, Netherlands, Chile). Cattle (n=80), sheep (n=40), goats (n=40), dromedary camels (n=155), and various other camelid species (n=34) were tested for specific serum IgG by protein microarray using the receptor-binding S1 subunits of spike proteins of MERS-CoV, severe acute respiratory syndrome coronavirus, and human coronavirus OC43. Results were confirmed by virus neutralisation tests for MERS-CoV and bovine coronavirus. Findings 50 of 50 (100%) sera from Omani camels and 15 of 105 (14%) from Spanish camels had protein-specific antibodies against MERS-CoV spike. Sera from European sheep, goats, cattle, and other camelids had no such antibodies. MERS-CoV neutralising antibody titres varied between 1/320 and 1/2560 for the Omani camel sera and between 1/20 and 1/320 for the Spanish camel sera. There was no evidence for cross-neutralisation by bovine coronavirus antibodies. Interpretation MERS-CoV or a related virus has infected camel populations. Both titres and seroprevalences in sera from different locations in Oman suggest widespread infection. Funding European Union, European Centre For Disease Prevention and Control, Deutsche Forschungsgemeinschaft.

negative: Emerging Respiratory Viruses Other than Influenza Non-influenza respiratory virus infections are common worldwide and contribute to morbidity and mortality in all age groups. The recently identified Middle East respiratory syndrome coronavirus has been associated with rapidly progressive pneumonia and high mortality rate. Adenovirus 14 has been increasingly recognized in severe acute respiratory illness in both military and civilian individuals. Rhinovirus C and human bocavirus type 1 have been commonly detected in infants and young children with respiratory tract infection and studies have shown a positive correlation between respiratory illness and high viral loads, mono-infection, viremia, and/or serologically-confirmed primary infection.

negative: Does the Bacillus Calmette–Guérin vaccine provide protection from COVID-19? OBJECTIVE: The novel coronavirus pandemic is ravaging throughout the world. It has infected more than 1.2 million people and killed more than 64,000. Frantic research is underway to find prevention and cure. Of late, Bacillus Calmette–Guérin (BCG) has been speculated as a possible protection from COVID-19. We sought to investigate the evidence behind the claim. MATERIAL AND METHODS: Data were collected regarding the total number of COVID-19 cases per million and total number of COVID-19 deaths per million in various countries. The BCG vaccination policies of these countries were also obtained. RESULTS: It was seen that the countries with no universal BCG policy had a mean 1272.9 (median 795) cases per million and 80.7 deaths (median 18) per million population. On the contrary, the countries with a universal BCG vaccination policy had a mean 131.2 (median 40) cases per million and 4 deaths (median 1) per population. The difference is highly significant (P < 0.001). CONCLUSION: The data strongly support the hypothesis that BCG may offer protection from COVID-19. Heterologous protection offered by BCG through production of trained immunity, epigenetic reprogramming of monocytes, non-specific activation of NK cells, and increase of pro-inflammatory cytokines (particularly, tumor necrosis factor [TNF]-alpha and interleukin 1 beta) production may be the mechanism behind its cross- protection against the novel coronavirus.

negative: Anwendungsgebiete für rekombinante Antikörper Antikörper werden seit Jahrzenten in zahlreichen unterschiedlichen Assays eingesetzt. Der wohl meistverbreitete Assay in der Forschung und Diagnostik ist der Immunblot, auch häufig als Westernblot bezeichnet. Hier werden zuerst Proteine mittels SDS-PAGE aufgetrennt, dann auf eine Nitrocellulose- oder PVDF-Membran übertragen und die nachzuweisenden Proteine mit Hilfe eines Detektionsantikörpers gefärbt.

negative: Influenza species and subtypes circulation among hospitalized patients in Laleh hospital during two influenza seasonal (2016-2017 and 2017-2018) using a multiplex Real Time-Polymerase Chain Reaction The introduction of polymerase chain reaction (PCR) techniques has improved the detection of respiratory viruses, particularly with the use of multiplex real-time technique with the capability of simultaneous detection of various pathogens in a single reaction. The aim of this study was to apply the above technology for the diagnosis of influenza infections and at the same time to differentiate between common flu species between hospitalized patients in Laleh hospital (Iran) between two flu seasons (2016-2017 and 2017-2018). Different respiratory specimens were collected from 540 patients from a period of December 2016 to May 2018 and were sent to the laboratory for molecular diagnosis. RNAs were extracted and subsequently, a multiplex real time PCR identifying flu A, flu B and typing flu A (H1N1) was carried out. The mean age of patients was 47.54±23.96. 216 (40%) and 321 (60%) of subjects were male and female, respectively. 219 out of 540 (40.5%) were positive for influenza infection including flu A (n=97, 44.3%), flu A (H1N1) (n=45, 20.7%) and flu B (n=77, 35%). Flu A was the dominant species on 2016-2017 and flu B was the major species on 2017-2018. Flu A (H1N1) was comparable in both time periods. Flu infections were most frequently diagnosed in age groups 21-40. Flu-positive patients suffered more from body pain and sore throat than flunegative patients with significant statistical difference (P values <0.001). The mean duration of hospitalization was shorter for flu-positive patients (P value = 0.016). Application of multiplex real time PCR could facilitate the influenza diagnosis in a short period of time, benefiting patients from exclusion of bacterial infections and avoiding unnecessary antibiotic therapy. Influenza diagnosis was not achieved in up to 60% of flu-like respiratory infections, suggesting the potential benefit of adopting the same methodology for assessing the involvement of other viral or/and bacterial pathogens in those patients.

negative: Thromboinflammation and the hypercoagulability of COVID-19

negative: Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2): Emergence, History, Basic and Clinical Aspects Abstract In late December 2019, the world woke to a reality of a pandemic of Coronavirus Disease (COVID-19), elicited by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), which belongs to a group of β-coronavirus. The potential to cause life-threatening respiratory failure and rapid transmission puts COVID-19 in the list of Public Health Emergency of International Concern (PHEIC). In the last two decades, this is the 3rd deadliest Coronavirus pandemic, following SARS which lasted between 2002 and 2003 and Middle East Respiratory Syndrome (MERS) from 2012 till date. Globally and as of April 1st 2020, COVID-19 has affected 924,688 individuals in over 200 countries, causing 46,368 fatalities. While the SARS-CoV-2 originated in China with over 82,724 confirmed cases and more than 3000 deaths as at the time of writing this review, the rapid transmission of SARS-CoV-2 has resulted in exponential increase in the number of cases outside of China to about 10 times the report case and death in mainland China. SARS-CoV-2 is suspected to be zoonotic in nature as genetic studies have shown sequence similarity to viruses originating from bats. Extreme precautionary measures, such as curfew, shutting of borders and quarantining of individuals suspected to be infected have been instituted with immediate effect; however, due to individuals that are asymptomatic, uncontrolled human-to-human transmission has resulted in exponential infection rate and numerous loss of lives even with this lockdown measures. This review article summarizes the developing situation surrounding the SARS-CoV-2 pandemic with respect to its epidemiology, unique genomic structure, possible origins, transmission, pathogenesis, comparison with other deadly species of Coronaviruses (CoV) and emerging treatment strategies built on informed literature.

negative: Potential Neurologic and Oncologic Implications of the Novel Coronavirus

negative: Mechanisms of Adaptive Immunity to Porcine Reproductive and Respiratory Syndrome Virus The adaptive immune response is necessary for the development of protective immunity against infectious diseases. Porcine reproductive and respiratory syndrome virus (PRRSV), a genetically heterogeneous and rapidly evolving RNA virus, is the most burdensome pathogen of swine health and wellbeing worldwide. Viral infection induces antigen-specific immunity that ultimately clears the infection. However, the resulting immune memory, induced by virulent or attenuated vaccine viruses, is inconsistently protective against diverse viral strains. The immunological mechanisms by which primary and memory protection are generated and used are not well understood. Here, we summarize current knowledge regarding cellular and humoral components of the adaptive immune response to PRRSV infection that mediate primary and memory immune protection against viruses.

negative: Towards treatment planning of COVID-19: Rationale and hypothesis for the use of multiple immunosuppressive agents: anti-antibodies, immunoglobulins, and corticosteroids Abstract The novel coronavirus, SARS-CoV2, can cause a potentially fatal disease, COVID-19, in humans. Here, we will provide an overview of therapeutic options for COVID-19. Plasma from patients recovered from COVID-19 that contains antibodies against SARS-CoV2 has shown promising results in patients with severe COVID-19. Also, IVIG, combined with moderate-dose of corticosteroids, might improve patient outcomes. Evidence links COVID-19 to variable degrees of inflammation. Studies show that the use of corticosteroids might accelerate recovery from COVID-19. There are, however, no controlled clinical trials that show whether the use of corticosteroids can reduce COVID-19-related death. Also, the pro-inflammatory cytokine IL6 is the best-documented cytokine in COVID-19 correlated with severity, criticality, viral load, and prognosis of patients with COVID-19. Tocilizumab, a monoclonal antibody against IL6, could confer clinical benefit in patients with high IL6 levels. Essential elements that process SARS-CoV2 cell entry and specific characteristics that allow SARS-CoV2 to escape the immune system have the potential as targets for COVID-19 therapy.

negative: Molecular conservation and Differential mutation on ORF3a gene in Indian SARS-CoV2 genomes A global emergency due to the COVID-19 pandemic demands various studies related to genes and genomes of the SARS-CoV2. Among other important proteins, the role of accessory proteins are of immense importance in replication, regulation of infections of the coronavirus in the hosts. The largest accessory proteins in the SARS-CoV2 genome is ORF3a which modulates the host response to the virus infection and consequently it plays an important role in pathogenesis. In this study, an attempt is made to decipher the conservation of nucleotides, dimers, codons and amino acids in the ORF3a genes across thirty two genomes of Indian patients. ORF3a gene possesses single and double point mutations in Indian SARS-CoV2 genomes suggesting the change of SARS-CoV2’s virulence property in Indian patients. We find that the parental origin of the ORF3a gene over the genomes of SARS-CoV2 and Pangolin-CoV is same from the phylogenetic analysis based on conservations of nucleotides and so on. This study highlights the accumulation of mutation on ORF3a in Indian SARS-CoV2 genomes which may provide the designing therapeutic approach against SARS-CoV2.

negative: Chapter 11 New Technologies for Monitoring Marine Mammal Health Abstract Omics technologies have been developed in recent decades and applied to different subjects, although the greatest advancements have been achieved in human biology and disease. Genome sequencing and the exploration of its coding and noncoding regions are rapidly yielding meaningful answers to diverse questions, relating genome information to protein activity to environmental changes. In the past, marine mammal genetic and transcriptional studies have been restricted due to the lack of reference genomes. But the advance of high-throughput sequencing is revolutionizing the life sciences technologies. As long-lived organisms, at the top of the food chain, marine mammals play an important role in marine ecosystems and while their protected status is in favor of conservation of the species, it also complicates the researcher's approach to traditional measurements of health. Omics data generated by high-throughput technologies will represent an important key for improving the scientific basis for understanding both marine mammal and environment health.

negative: Immune responses with DNA vaccines encoded different gene fragments of severe acute respiratory syndrome coronavirus in BALB/c mice Abstract To analyze the immune responses of DNA vaccine encoded different gene fragments of severe acute respiratory syndrome coronavirus (SARS-Cov), SARS-Cov gene fragments of membrane (M), nucleocapsid (N), spike a (Sa), and spike b (Sb) proteins were cloned into pcDNA3.1 (Invitrogen) vector to form plasmids pcDNAM, pcDNAN, pcDNASa, and pcDNASb, respectively. After mice were immunized intramuscularly with pcDNAM, pcDNAN or pcDNASa–pcDNASb plasmid, blood was collected and serum was separated. Humoral immune response was detected with the enzyme-linked immunosorbent assay, and cellular immune response of SARS-Cov DNA vaccines was detected with lymphoproliferation assay and cytotoxic T lymphocyte assay. Results show that cellular and humoral immune responses can be detected after immunization with pcDNAM, pcDNAN or pcDNASa–pcDNASb plasmids in BALB/c mice. However, pcDNAM stimulated the highest cellular immune response than other plasmids, and pcDNASa–pcDNASb stimulated the highest humoral immune response in week 12. The present results not only suggest that DNA immunization with pcDNAM, pcDNAN or pcDNASa–pcDNASb could be used as potential DNA vaccination approaches to induce antibody in BALB/c mice, but also to illustrate that gene immunization with these SARS DNA vaccines different immune response characters.

negative: SARS Cov2 infection in a renal transplanted patients. A case report. The clinical manifestation of COVID-19 can vary from an asymptomatic course to ARDS requiring invasive mechanical ventilation and extracorporeal membrane oxygenation. A kidney transplanted patient infected with SARS CoV2 infection showed a mild disease despite immune suppression. It is possible that Immunosuppression can "be protective" as the cytokine storm is an important factor in the disease story. Despite the good outcome reported in the present case report, is remains of vital importance the solid organ transplant patients use precautions in order to avoid the infection.

negative: Severe Acute Respiratory Syndrome Coronavirus Infection in Vaccinated Ferrets Background. Development of vaccines to prevent severe acute respiratory syndrome (SARS) is limited by the lack of well-characterized animal models. Previous vaccine reports have noted robust neutralizing antibody and inflammatory responses in ferrets, resulting in enhanced hepatitis. Methods. We evaluated the humoral immune response and pathological end points in ferrets challenged with the Urbani strain of SARS-associated coronavirus (SARS-CoV) after having received formalin-inactivated whole-virus vaccine or mock vaccine. Results. Humoral responses were observed in ferrets that received an inactivated virus vaccine. Histopathological findings in lungs showed that infection of ferrets produced residual lung lesions not seen in both mock and vaccinated ferrets. SARS-CoV infection demonstrated bronchial and bronchiolar hyperplasia and perivascular cuffing in ferret lung tissue, as seen previously in infected mice. No evidence of enhanced disease was observed in any of the ferrets. All of the ferrets cleared the virus by day 14, 1 week earlier if vaccinated. Conclusions. The vaccine provided mild immune protection to the ferrets after challenge; however, there was no evidence of enhanced liver or lung disease induced by the inactivated whole-virus vaccine. The ferret may provide another useful model for evaluating SARS vaccine safety and efficacy.

negative: Novel vaccine strategies against emerging viruses One of the main public health concerns of emerging viruses is their potential introduction into and sustained circulation among populations of immunologically naïve, susceptible hosts. The induction of protective immunity through vaccination can be a powerful tool to prevent this concern by conferring protection to the population at risk. Conventional approaches to develop vaccines against emerging pathogens have significant limitations: lack of experimental tools for several emerging viruses of concern, poor immunogenicity, safety issues, or lack of cross-protection against antigenic variants. The unpredictability of the emergence of future virus threats demands the capability to rapidly develop safe, effective vaccines. We describe some recent advances in new vaccine strategies that are being explored as alternatives to classical attenuated and inactivated vaccines, and provide examples of potential novel vaccines for emerging viruses. These approaches might be applied to the control of many other emerging pathogens.

negative: Therapeutic strategies in an outbreak scenario to treat the novel coronavirus originating in Wuhan, China A novel coronavirus (2019-nCoV) originating in Wuhan, China presents a potential respiratory viral pandemic to the world population. Current efforts are focused on containment and quarantine of infected individuals. Ultimately, the outbreak could be controlled with a protective vaccine to prevent 2019-nCoV infection. While vaccine research should be pursued intensely, there exists today no therapy to treat 2019-nCoV upon infection, despite an urgent need to find options to help these patients and preclude potential death. Herein, I review the potential options to treat 2019-nCoV in patients, with an emphasis on the necessity for speed and timeliness in developing new and effective therapies in this outbreak. I consider the options of drug repurposing, developing neutralizing monoclonal antibody therapy, and an oligonucleotide strategy targeting the viral RNA genome, emphasizing the promise and pitfalls of these approaches. Finally, I advocate for the fastest strategy to develop a treatment now, which could be resistant to any mutations the virus may have in the future. The proposal is a biologic that blocks 2019-nCoV entry using a soluble version of the viral receptor, angiotensin-converting enzyme 2 (ACE2), fused to an immunoglobulin Fc domain (ACE2-Fc), providing a neutralizing antibody with maximal breath to avoid any viral escape, while also helping to recruit the immune system to build lasting immunity. The ACE2-Fc therapy would also supplement decreased ACE2 levels in the lungs during infection, thereby directly treating acute respiratory distress pathophysiology as a third mechanism of action. The sequence of the ACE2-Fc protein is provided to investigators, allowing its possible use in recombinant protein expression systems to start producing drug today to treat patients under compassionate use, while formal clinical trials are later undertaken. Such a treatment could help infected patients before a protective vaccine is developed and widely available in the coming months to year(s).

negative: Single intranasal immunization with chimpanzee adenovirus-based vaccine induces sustained and protective immunity against MERS-CoV infection The recently identified Middle East Respiratory Syndrome Coronavirus (MERS-CoV) causes severe and fatal acute respiratory illness in humans. However, no approved prophylactic and therapeutic interventions are currently available. The MERS-CoV envelope spike protein serves as a crucial target for neutralizing antibodies and vaccine development, as it plays a critical role in mediating viral entry through interactions with the cellular receptor, dipeptidyl peptidase 4 (DPP4). Here, we constructed a recombinant rare serotype of the chimpanzee adenovirus 68 (AdC68) that expresses full-length MERS-CoV S protein (AdC68-S). Single intranasal immunization with AdC68-S induced robust and sustained neutralizing antibody and T cell responses in BALB/c mice. In a human DPP4 knock-in (hDPP4-KI) mouse model, it completely protected against lethal challenge with a mouse-adapted MERS-CoV (MERS-CoV-MA). Passive transfer of immune sera to naïve hDPP4-KI mice also provided survival advantages from lethal MERS-CoV-MA challenge. Analysis of sera absorption and isolated monoclonal antibodies from immunized mice demonstrated that the potent and broad neutralizing activity was largely attributed to antibodies targeting the receptor binding domain (RBD) of the S protein. These results show that AdC68-S can induce protective immune responses in mice and represent a promising candidate for further development against MERS-CoV infection in both dromedaries and humans.

negative: Review on Machine and Deep Learning Models for the Detection and Prediction of Coronavirus The novel Coronavirus disease has increased rapidly in the Wuhan city of China in December 2019. This fatal virus has spread across the whole world like a fire in different stages and affecting millions of population and thousands of deaths worldwide. Therefore, it is essential to classify the infected people, so that they can take the precaution in the earlier stages. Also, due to the increasing cases spread of Coronavirus, there are only limited numbers of polymerase change reaction kits available in the hospitals for testing Coronavirus patients. That why it is extremely important to develop artificial intelligence-based automatic diagnostic tools to classify the Coronavirus outbreak. The objective of this paper is to know the novel disease epidemiology, major prevention from spreading of Coronavirus Severe Acute Respiratory Syndrome, and to assess the machine and deep learning-based architectures performance that is proposed in the present year for classification of Coronavirus images such as, X-Ray and computed tomography. Specifically, advanced deep learning-based algorithms known as the Convolutional neural network, which plays a great effect on extracting highly essential features, mostly in terms of medical images. This technique, with using CT and X-Ray image scans, has been adopted in most of the recently published articles on the Coronavirus with remarkable results. Furthermore, according to this paper, this can be noted and said that deep learning technology has potential clinical applications.

negative: Chloroquine: A Potential Drug in the COVID-19 Scenario Today, the whole world is fighting a public health emergency called ‘COVID-19’ caused by a new infectious virus called SARS-CoV2. Any person can catch COVID-19 from an infected person via aerosol droplets when the person coughs, sneezes, or speaks. To limit such a transmission, World Health Organization (WHO) has recommended people to wear masks and physically distance themselves by staying at least 1 m (3 feet) away from others. As aerosol droplets (by cough or sneeze) land on objects and surfaces around the person such as tables, doorknobs and handrails, and remain active on these surfaces for hours to days, people are advised to use soaps for at least 20 s. and alcohol-based sanitizers as well. As the public made efforts, clinicians and researchers investigated and found that drugs which were initially used to treat other diseases may work as a treatment option for COVID-19. One of those drugs was Chloroquine and its related derivative called hydroxychloroquine. In this review article, we have systematically searched for details of COVID-19 pandemic till May 2020 and assembled few data pertaining to (i) Corona viruses; (ii) SARS-CoV2, the virus that causes COVID-19’ and (iii) How chloroquine and hydroxychloroquine mediates anti-viral effect in both prophylactic and therapeutic setting. These data have been acquired mostly from PubMed and websites of WHO and Indian Council for Medical Research (ICMR). We did a systematic search and found that the properties of chloroquine are very much essential for the COVID-19 scenario. We also bring to you some evidence that the anti-lysosomal activity of chloroquine may be increased by botanicals like betulinic acid.

negative: Will There Be an Epidemic of Corollary Illnesses Linked to a COVID-19-Related Recession? Currently, US unemployment claims have skyrocketed to 30 million in the past six weeks, continuing in a stark upward trend, and labor economists estimate the unemployment rate at minimally 18.3%. These unemployment figures are a feature of the COVID-19 recession that is characterized by sharp gross domestic product (GDP) growth decline. Despite the greatly damaging impact of the opioid crisis over 2015 to 2017 resulting in a decrease in life expectancy over these three years, the long-term increases in average GDP per capita from 1999 to 2018 managed to save lives on average (i.e., age-adjusted mortality rates declined in the United States). For example, during 1999 to 2018, the average GDP per capita annually increased 1.2%, whereas the related age-adjusted mortality rate has shown an annual decrease of approximately 1% on average (0.99%). However, recessions erase some of this beneficial effect of GDP growth on mortality reduction.1 (Am J Public Health. Published online ahead of print May 14, 2020: e1-e2. doi:10.2105/AJPH.2020.305724).

negative: Cell-Membrane-Mimicking Nanodecoys against Infectious Diseases [Image: see text] Infectious diseases are a leading cause of mortality worldwide, with viruses and bacteria in particular having enormous impacts on global healthcare. One major challenge in combatting such diseases is a lack of effective drugs or specific treatments. In addition, drug resistance to currently available therapeutics and adverse effects caused by long-term overuse are both serious public health issues. A promising treatment strategy is to employ cell-membrane mimics as decoys to trap and to detain the pathogens. In this Perspective, we briefly review the infection mechanisms adopted by different pathogens at the cellular membrane interface and highlight the applications of cell-membrane-mimicking nanodecoys for systemic protection against infectious diseases. We also discuss the implication of nanodecoy–pathogen complexes in the development of vaccines. We anticipate this Perspective will provide new insights on design and development of advanced materials against emerging infectious diseases.

negative: Total predicted MHC-I epitope load is inversely associated with mortality from SARS-CoV-2 Polymorphism in MHC-I protein sequences across human populations significantly impacts their binding to viral peptides and alters T cell immunity to infection. Prioritization of MHC-I restricted viral epitopes remains a fundamental challenge for understanding adaptive immunity to SARS-CoV-2. Here, we present a consensus MHC-I binding prediction model, EnsembleMHC, based on the biochemical and structural basis of peptide presentation to aid the discovery of SARS-CoV-2 MHC-I peptides. We performed immunopeptidome predictions of SARS-CoV-2 proteins across 52 common MHC-I alleles identifying 658 high confidence peptides. Analysis of the resulting peptide-allele assignment distribution demonstrated significant variation across the allele panel up to an order of magnitude. Using MHC-I population-based allele frequencies, we estimated the average SARS-CoV-2 peptide population binding capacity across 21 individual countries. We have discovered a strong inverse association between the predicted population SARS-CoV-2 peptide binding capacity and overall mortality from SARS-CoV-2. Furthermore, we found that the consideration of only structural proteins produced a stronger association with observed death rate, highlighting their importance in protein-targeted immune responses. The 108 predicted SARS-CoV-2 structural protein peptides were shown to be derived from enriched regions in the originating protein, and present minimal risk for disruption by mutation. These results suggest that the immunologic fitness of both individuals and populations to generate class I-restricted T cell immunity to SARS-CoV-2 infection may impact clinical outcome from viral infection.

negative: Potential interventions for novel coronavirus in China: A systematic review An outbreak of a novel coronavirus (COVID‐19 or 2019‐CoV) infection has posed significant threats to international health and the economy. In the absence of treatment for this virus, there is an urgent need to find alternative methods to control the spread of disease. Here, we have conducted an online search for all treatment options related to coronavirus infections as well as some RNA‐virus infection and we have found that general treatments, coronavirus‐specific treatments, and antiviral treatments should be useful in fighting COVID‐19. We suggest that the nutritional status of each infected patient should be evaluated before the administration of general treatments and the current children's RNA‐virus vaccines including influenza vaccine should be immunized for uninfected people and health care workers. In addition, convalescent plasma should be given to COVID‐19 patients if it is available. In conclusion, we suggest that all the potential interventions be implemented to control the emerging COVID‐19 if the infection is uncontrollable.

negative: ACE2 Expression is Increased in the Lungs of Patients with Comorbidities Associated with Severe COVID-19 The pandemic caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has resulted in several thousand deaths worldwide in just a few months. Patients who died from Coronavirus disease 2019 (COVID-19) often had comorbidities, such as hypertension, diabetes, and chronic obstructive lung disease. The angiotensin-converting enzyme 2 (ACE2) was identified as a crucial factor that facilitates SARS-CoV2 to bind and enter host cells. To date, no study has assessed the ACE2 expression in the lungs of patients with these diseases. Here, we analyzed over 700 lung transcriptome samples of patients with comorbidities associated with severe COVID-19 and found that ACE2 was highly expressed in these patients, compared to control individuals. This finding suggests that patients with such comorbidities may have higher chances of developing severe COVID-19. We also found other genes, such as RAB1A, that can be important for SARS-CoV-2 infection in the lung. Correlation and network analyses revealed many potential regulators of ACE2 in the human lung, including genes related to histone modifications, such as HAT1, HDAC2, and KDM5B. In fact, epigenetic marks found in ACE2 locus were compatible to with those promoted by KDM5B. Our systems biology approach offers a possible explanation for increase of COVID-19 severity in patients with certain comorbidities.

negative: SARS-CoV-2 is sensitive to type I interferon pretreatment. SARS-CoV-2, a novel coronavirus (CoV), has recently emerged causing an ongoing outbreak of viral pneumonia around the world. While genetically distinct from the original SARS-CoV, both group 2B CoVs share similar genome organization and origins to coronaviruses harbored in bats. Importantly, initial guidance has used insights from SARS-CoV infection to inform treatment and public health strategies. In this report, we evaluate type-I Interferon (IFN-I) sensitivity of SARS-CoV-2 relative to the original SARS-CoV. Our results indicate that while SARS-CoV-2 maintains similar viral replication kinetics to SARS-CoV in Vero cell, the novel CoV is much more sensitive to IFN-I pretreatment. Examining transcriptional factor activation and interferon stimulated gene (ISG) induction, SARS-CoV-2 in the context of type I IFN induces phosphorylation of STAT1 and increased ISG proteins. In contrast, the original SARS-CoV has no evidence for STAT1 phosphorylation or ISG protein increases even in the presence of type I IFN pretreatment. Next, we examined IFN competent Calu3 2B4 cells finding SARS-CoV-2 had reduced viral replication relative to SARS-CoV and induced STAT1 phosphorylation late during infection. Finally, we examined homology between SARS-CoV and SARS-CoV-2 in viral proteins shown to be interferon antagonist. The absence of open reading frame (ORF) 3b and significant changes to ORF6 suggest the two key IFN antagonists may not maintain equivalent function in SARS-CoV-2. Together, the results identify key differences in susceptibility to the IFN-I response between SARS-CoV and SARS-CoV-2. that could help inform disease progression, treatment options, and animal model development.

negative: Differential Diagnosis of Common Acute Toxicologic Versus Nontoxicologic Illness This table outlines common toxicologic versus nontoxicologic rule outs based on clinical abnormalities seen in an acutely ill animal. The purpose is to provide an initial guideline for considering toxicologic versus nontoxicologic rule outs when a patient is presented to a practicing veterinarian. Major clinical abnormalities followed by common toxicologic rule outs and non-toxicologic rule outs have been listed so that practicing veterinarians can narrow down an etiology quickly. Based on history, physical examination findings, and blood work changes, once a reasonable etiology has been narrowed down or established, the reader is encouraged to review a more detailed discussion on management of the particular poisoning or disease listed in this or other references.

negative: SARS - CoV-2: Reasons of epidemiology of severe ill disease cases and therapeutic approach using trivalent vaccine (tetanus, diphtheria and Bordetella pertussis) The novel coronavirus Covid-19 follows transmission route and clinical presentation of all community-acquired coronaviruses. Instead, the rate of transmission is significative higher, with a faster spread of the virus responsible of the worldwide outbreak and a significative higher mortality rate due to the development of a severe lung injury. Most noteworthy is the distribution of death rate among age groups. Children and younger people are almost protected from severe clinical presentation. Possible explanation of this phenomenon could be the ability of past vaccinations (especially tetanic, diphtheria toxoids and inactivated bacteria as pertussis) to stimulate immune system and to generate a scattered immunity against non-self antigens in transit, as coronaviruses and other community-circulating viruses and make immune system readier to develop specific immunity against Covid-19. The first support to this hypothesis is the distribution of mortality rate during historical pandemics ("Spanish flu" 1918, "Asian flu" 1956 and "the Hong Kong flu" 1968) among age groups before and after the introduction of vaccines. The immunological support to the hypothesis derives from recent studies about immunotherapy for malignancies, which propose the use of oncolytic vaccines combined with toxoids in order to exploit CD4 + memory T cell recall in supporting the ongoing anti-tumour response. According to this hypothesis vaccine formulations (tetanus, diphtheria, Bordetella pertussis) could be re-administrate after the first contact with Covid-19, better before the development of respiratory severe illness and of course before full-blown ARDS (Acute Respiratory Distress Syndrome). The CD4 + memory exploiting could help immune system to recall immunity of already know antigens against coronaviruses, avoiding or limiting "lung crash" until virus specific immunity develops and making it faster and prolonged. Finally, this administration could be helpful not only in already infected patients, but also before infection. In fact, people could have an immune system more ready when the contact with the Covid-19 will occur.

negative: Alveolar Macrophage Dysfunction and Increased PD-1 Expression During Chronic SIV Infection of Rhesus Macaques HIV infected individuals have been shown to be pre-disposed to pulmonary infections even while receiving anti-retroviral therapy. Alveolar macrophages (AMs) play a critical role in lung innate immunity, but contradictory results have been reported regarding their functionality following HIV infection. Here, using the SIV rhesus macaque model, we document the effect of SIV infection on the phenotypic and functional properties of AMs. Following infection with SIV(mac251), AMs in bronchoalveolar lavage (BAL) sampled over 2- to 20-weeks post-infection (wpi) were compared to those in BAL samples from naïve macaques. AM expression of proinflammatory cytokines TNF-α, IL-6, IL-1β, and chemokine RANTES drastically increased 2-wpi compared to AMs of naïve macaques (p < 0.0001 for all), but dropped significantly with progression to chronic infection. Phagocytic activity of AMs 2-and 4-wpi was elevated compared to AMs of naive animals (p = 0.0005, p = 0.0004, respectively) but significantly decreased by 12-wpi (p = 0.0022, p = 0.0019, respectively). By 20-wpi the ability of AMs from chronically infected animals to perform SIV-specific antibody-dependent phagocytosis (ADP) was also diminished (p = 0.028). Acute SIV infection was associated with increased FcγRIII expression which subsequently declined with disease progression. Frequency of FcγRIII(+) AMs showed a strong trend toward correlation with SIV-specific ADP, and at 2-wpi FcγRIII expression negatively correlated with viral load (r = −0.6819; p = 0.0013), suggesting a contribution to viremia control. Importantly, PD-1 was found to be expressed on AMs and showed a strong trend toward correlation with plasma viral load (r = 0.8266; p = 0.058), indicating that similar to over-expression on T-cells, PD-1 expression on AMs may also be associated with disease progression. Further, AMs predominantly expressed PD-L2, which remained consistent over the course of infection. PD-1 blockade enhanced SIV-specific ADP by AMs from chronic infection indicating that the PD-1/PD-L2 pathway may modulate functional activity of AMs at that stage. These findings provide new insight into the dynamics of SIV infection leading to AM dysfunction and alteration of pulmonary innate immunity. Our results suggest new pathways to exploit in developing therapies targeting pulmonary disease susceptibility in HIV-infected individuals.

negative: Chapter 13 Viral Disease Abstract This chapter discusses infections of rats with viruses in the following 14 virus families: Adenoviridae, Arenaviridae, Coronaviridae, Flaviviridae, Hantaviridae, Hepeviridae, Herpesviridae, Paramyxoviridae, Parvoviridae, Picornaviridae, Pneumoviridae, Polyomaviridae, Poxviridae, and Reoviridae. Serological surveys indicate that parvoviruses, coronaviruses, cardioviruses, and pneumoviruses are the most prevalent in laboratory rats. A new polyomavirus and a new cardiovirus that cause disease in laboratory rats are described. Metagenomic analyses of feces or intestinal contents from wild rats have detected viruses from an additional nine virus families that could potentially cause infections in laboratory rats.

negative: Pre-existing immunity against Ad vectors: Humoral, cellular, and innate response, what's important? Pre-existing immunity against human adenovirus (HAd) serotype 5 derived vector in the human population is widespread, thus hampering its clinical use. Various components of the immune system, including neutralizing antibodies (nAbs), Ad specific T cells and type I IFN activated NK cells, contribute to dampening the efficacy of Ad vectors in individuals with pre-existing Ad immunity. In order to circumvent pre-existing immunity to adenovirus, numerous strategies, such as developing alternative Ad serotypes, varying immunization routes and utilizing prime-boost regimens, are under pre-clinical or clinical phases of development. However, these strategies mainly focus on one arm of pre-existing immunity. Selection of alternative serotypes has been largely driven by the absence in the human population of nAbs against them with little attention paid to cross-reactive Ad specific T cells. Conversely, varying the route of immunization appears to mainly rely on avoiding Ad specific tissue-resident T cells. Finally, prime-boost regimens do not actually circumvent pre-existing immunity but instead generate immune responses of sufficient magnitude to confer protection despite pre-existing immunity. Combining the above strategies and thus taking into account all components regulating pre-existing Ad immunity will help further improve the development of Ad vectors for animal and human use.

negative: Rational Vaccine Design in the Time of COVID-19 As scientists consider SARS-CoV-2 vaccine design, we discuss problems that may be encountered and how to tackle them by what we term “rational vaccine design.” We further discuss approaches to pan-coronavirus vaccines. We draw on experiences from recent research on several viruses including HIV and influenza, as well as coronaviruses.

negative: Development of CRISPR as an Antiviral Strategy to Combat SARS-CoV-2 and Influenza Summary The coronavirus disease 2019 (COVID-19) pandemic, caused by the SARS-CoV-2 virus, has highlighted the need for antiviral approaches that can target emerging viruses with no effective vaccines or pharmaceuticals. Here, we demonstrate a CRISPR-Cas13-based strategy, PAC-MAN (prophylactic antiviral CRISPR in human cells), for viral inhibition that can effectively degrade RNA from SARS-CoV-2 sequences and live influenza A virus (IAV) in human lung epithelial cells. We designed and screened CRISPR RNAs (crRNAs) targeting conserved viral regions and identified functional crRNAs targeting SARS-CoV-2. This approach effectively reduced H1N1 IAV load in respiratory epithelial cells. Our bioinformatic analysis showed that a group of only six crRNAs can target more than 90% of all coronaviruses. With the development of a safe and effective system for respiratory tract delivery, PAC-MAN has the potential to become an important pan-coronavirus inhibition strategy.

negative: An insertion unique to SARS-CoV-2 exhibits superantigenic character strengthened by recent mutations Multisystem Inflammatory Syndrome in Children (MIS-C) associated with Coronavirus Disease 2019 (COVID-19) is a newly recognized condition in which children with recent SARS-CoV-2 infection present with a constellation of symptoms including hypotension, multiorgan involvement, and elevated inflammatory markers. These symptoms and the associated laboratory values strongly resemble toxic shock syndrome, an escalation of the cytotoxic adaptive immune response triggered upon the binding of pathogenic superantigens to MHCII molecules and T cell receptors (TCRs). Here, we used structure-based computational models to demonstrate that the SARS-CoV-2 spike (S) exhibits a high-affinity motif for binding TCR, interacting closely with both the α- and β-chains variable domains’ complementarity-determining regions. The binding epitope on S harbors a sequence motif unique to SARS-CoV-2 (not present in any other SARS coronavirus), which is highly similar in both sequence and structure to bacterial superantigens. Further examination revealed that this interaction between the virus and human T cells is strengthened in the context of a recently reported rare mutation (D839Y/N/E) from a European strain of SARS-CoV-2. Furthermore, the interfacial region includes selected residues from a motif shared between the SARS viruses from the 2003 and 2019 pandemics, which has intracellular adhesion molecule (ICAM)-like character. These data suggest that the SARS-CoV-2 S may act as a superantigen to drive the development of MIS-C as well as cytokine storm in adult COVID-19 patients, with important implications for the development of therapeutic approaches.

negative: Nsp1 proteins of group I and SARS coronaviruses share structural and functional similarities Abstract The nsp1 protein of the highly pathogenic SARS coronavirus suppresses host protein synthesis, including genes involved in the innate immune system. A bioinformatic analysis revealed that the nsp1 proteins of group I and SARS coronaviruses have similar structures. Nsp1 proteins of group I coronaviruses interacted with host ribosomal 40S subunit and did not inhibit IRF-3 activation. However, synthesis of host immune and non-immune proteins was inhibited by nsp1 proteins at both transcriptional and translational levels, similar to SARS coronavirus nsp1. These results indicate that different coronaviruses might employ the same nsp1 mechanism to antagonize host innate immunity and cell proliferation. However, nsp1 may not be the key determinant of viral pathogenicity, or the factor used by the SARS coronavirus to evade host innate immunity.

negative: Acute asthma management during SARS-CoV2-pandemic 2020 Background: The current COVID-19 pandemic has changed many medical practices in order to provide additional protection to both our patients and our healthcare providers. In many cases this includes seeing patients through electronic means such as telehealth or telephone rather than seeing them in person. Asthma exacerbations cannot always be treated in this way. Problem: Current emergency unit asthma guidelines recommend bronchodilators be administered by metered dose inhaler (MDI) and spacer for mild-moderate asthma and include it as a choice even in severe asthma, but many emergency units continue to prefer nebulised therapy for patients who urgently require beta-agonists. The utilization of nebulised therapy potentially increases the risk of aerosolization of the coronavirus. Since nosocomial transmission of respiratory pathogens is a major threat in the context of the SARS-CoV-2 pandemic, use of nebulised therapy is of even greater concern due to the potential increased risk of infection spread to nearby patients and health-care workers. Practical implications: We propose a risk stratification plan that aims to avoid nebulised therapy, when possible, by providing an algorithm to help better delineate those who require nebulised therapy. Protocols that include strategies to allow flexibility in using MDIs rather than nebulisers in all but the most severe patients should help mitigate this risk of aerosolised infection transmission to patients and health care providers. Furthermore, expedient treatment of patients with high dose MDI therapy augmented with more rapid initiation of systemic therapy may help ensure patients are less likely to deteriorate to the stage where nebulisers are required.

negative: Building resilience against biological hazards and pandemics: COVID-19 and its implications for the Sendai Framework Abstract 2020 has become the year of coping with COVID-19. This year was to be the “super year” for sustainability, a year of strengthening global actions to accelerate the transformations required for achieving the 2030 agenda. We argue that 2020 can and must be a year of both. Thus we call for more utilisation of the health-emergency disaster risk management (Health-EDRM) framework to complement current responses to COVID-19 and the patent risk of similar phenomena in the future. To make our case, we examine current responses to COVID-19 and their implications for the SFDRR. We argue that current mechanisms and strategies for disaster resilience, as outlined in the SFDRR, can enhance responses to epidemics or global pandemics such as COVID-19. In this regard, we make several general and DRR-specific recommendations. These recommendations concern knowledge and science provision in understanding disaster and health-related emergency risks, the extension of disaster risk governance to manage both disaster risks and potential health-emergencies, particularly for humanitarian coordination aspects; and the strengthening of community-level preparedness and response.

negative: Ecoepidemiology and complete genome comparison of different strains of severe acute respiratory syndrome-related Rhinolophus bat coronavirus in China reveal bats as a reservoir for acute, self-limiting infection that allows recombination events. Despite the identification of severe acute respiratory syndrome-related coronavirus (SARSr-CoV) in Rhinolophus Chinese horseshoe bats (SARSr-Rh-BatCoV) in China, the evolutionary and possible recombination origin of SARSr-CoV remains undetermined. We carried out the first study to investigate the migration pattern and SARSr-Rh-BatCoV genome epidemiology in Chinese horseshoe bats during a 4-year period. Of 1,401 Chinese horseshoe bats from Hong Kong and Guangdong, China, that were sampled, SARSr-Rh-BatCoV was detected in alimentary specimens from 130 (9.3%) bats, with peak activity during spring. A tagging exercise of 511 bats showed migration distances from 1.86 to 17 km. Bats carrying SARSr-Rh-BatCoV appeared healthy, with viral clearance occurring between 2 weeks and 4 months. However, lower body weights were observed in bats positive for SARSr-Rh-BatCoV, but not Rh-BatCoV HKU2. Complete genome sequencing of 10 SARSr-Rh-BatCoV strains showed frequent recombination between different strains. Moreover, recombination was detected between SARSr-Rh-BatCoV Rp3 from Guangxi, China, and Rf1 from Hubei, China, in the possible generation of civet SARSr-CoV SZ3, with a breakpoint at the nsp16/spike region. Molecular clock analysis showed that SARSr-CoVs were newly emerged viruses with the time of the most recent common ancestor (tMRCA) at 1972, which diverged between civet and bat strains in 1995. The present data suggest that SARSr-Rh-BatCoV causes acute, self-limiting infection in horseshoe bats, which serve as a reservoir for recombination between strains from different geographical locations within reachable foraging range. Civet SARSr-CoV is likely a recombinant virus arising from SARSr-CoV strains closely related to SARSr-Rh-BatCoV Rp3 and Rf1. Such frequent recombination, coupled with rapid evolution especially in ORF7b/ORF8 region, in these animals may have accounted for the cross-species transmission and emergence of SARS.

negative: Retinal pathology in multiple sclerosis: insight into the mechanisms of neuronal pathology

negative: Therapeutic strategies for critically ill patients with COVID-19 Since the 2019 novel coronavirus disease (COVID-19) outbreak originated from Wuhan, Hubei Province, China, at the end of 2019, it has become a clinical threat to the general population worldwide. Among people infected with the novel coronavirus (2019-nCoV), the intensive management of the critically ill patients in intensive care unit (ICU) needs substantial medical resource. In the present article, we have summarized the promising drugs, adjunctive agents, respiratory supportive strategies, as well as circulation management, multiple organ function monitoring and appropriate nutritional strategies for the treatment of COVID-19 in the ICU based on the previous experience of treating other viral infections and influenza. These treatments are referable before the vaccine and specific drugs are available for COVID-19.

negative: Children coronavirus dilemma Other reasons rather then absence of prior immunity could play a crucial role in the children coronavirus dilemma

negative: Contribution of type III interferons to antiviral immunity: location, location, location. Type I interferons (IFN-α/β) and the more recently identified type III IFNs (IFN-λ) function as the first line of defense against virus infection and regulate the development of both innate and adaptive immune responses. Type III IFNs were originally identified as a novel ligand-receptor system acting in parallel with type I IFNs, but subsequent studies have provided increasing evidence for distinct roles for each IFN family. In addition to their compartmentalized antiviral actions, these two systems appear to have multiple levels of cross-regulation and act coordinately to achieve effective antimicrobial protection with minimal collateral damage to the host.

negative: No indications for overt innate immune suppression in critically ill COVID-19 patients At the end of March 2020, there were in excess of 800.000 confirmed cases of coronavirus disease 2019 (COVID-19) worldwide. Several reports suggest that, in severe cases, COVID-19 may cause a hyperinflammatory 'cytokine storm'. However, unlike SARS-CoV infection, high levels of anti-inflammatory mediators have also been reported in COVID-19 patients. One study reported that 16% of COVID-19 patients who died developed secondary infection, which might indicate an immune-suppressed state. We explored kinetics of mHLA-DR expression, the most widely used marker of innate immune suppression in critically ill patients, in COVID-19 patients admitted to the ICU. Twenty-four confirmed COVID-19 patients were included, of which 75% was male and 79% had comorbidities. All patients were mechanically ventilated and exhibited large high levels of inflammatory parameters such as CRP and PCT. mHLA-DR expression levels were mostly within the normal range of 15000 - 45000 mAb/cell and showed no change over time. COVID-19 patients displayed notably higher mHLA-DR expression levels compared with bacterial septic shock patients. None of the COVID-19 patients developed a secondary infection. In conclusion, despite a pronounced inflammatory response, mHLA-DR expression kinetics indicate no overt innate immune suppression in COVID-19 patients. These data signify that innate immune suppression as a negative feedback mechanism following PAMP-induced inflammation appears not to be present in COVID-19.

negative: A Tale of Two Communities: Characterizing Reddit Response to COVID-19 through /r/China_Flu and /r/Coronavirus The COVID-19 pandemic has deeply impacted people's lives around the globe. During the extended lockdowns caused by the pandemic, online communities are crucial for people to access information and share experiences. In particular, two"new"communities have emerged on Reddit: /r/China_flu and /r/Coronavirus. By studying activities and users in these two communities, we provide a characterization of people's responses to COVID-19 on Reddit. First, we find that user activity peaks around March 17, when the World Health Organization (WHO) announced COVID-19 as a pandemic. Shortly after that, the activity levels of both communities have been declining week by week. We further illustrate the central role of these two communities in the emergence of COVID-related communities. Second, we study the differences between these two communities. /r/Coronavirus is recommended as the official community for COVID-19 on Reddit, while /r/China_flu adopts a loose moderation practice. As a result, we observe that these two communities are gradually growing apart and more extremism is being found in /r/China_flu. Finally, we examine the spillover effect of the COVID-19 pandemic on user activity across the entire Reddit platform. Our results show significant changes in user activities outside COVID-related communities. In subreddits related to finance, food, and countries/cities, user activity is recovering to the pre-pandemic level in late April and May as countries reopen, but subreddits related to travel and sports remain highly impacted and show lower activity levels than the pre-pandemic period. Our work highlights the strength of Reddit as a source for understanding public reactions to COVID-19 and the importance of content moderation on the Internet during a pandemic.

negative: Roles of meteorological conditions in COVID-19 transmission on a worldwide scale The novel coronavirus (SARS-CoV-2/ 2019-nCoV) identified in Wuhan, China, in December 2019 has caused great damage to public health and economy worldwide with over 140,000 infected cases up to date. Previous research has suggested an involvement of meteorological conditions in the spread of droplet-mediated viral diseases, such as influenza. However, as for the recent novel coronavirus, few studies have discussed systematically about the role of daily weather in the epidemic transmission of the virus. Here, we examine the relationships of meteorological variables with the severity of the outbreak on a worldwide scale. The confirmed case counts, which indicates the severity of COVID-19 spread, and four meteorological variables, i.e., air temperature, relative humidity, wind speed, and visibility, were collected daily between January 20 and March 11 (52 days) for 430 cities and districts all over China, 21 cities/ provinces in Italy, 21 cities/ provinces in Japan, and 51 other countries around the world. Four different time delays of weather (on the day, 3 days ago, 7 days ago, and 14 days ago) as to the epidemic situation were taken for modeling and we finally chose the weather two weeks ago to model against the daily epidemic situation as its correlated with the outbreak best. Taken Chinese cities as a discovery dataset, it was suggested that temperature, wind speed, and relative humidity combined together could best predict the epidemic situation. The meteorological model could well predict the outbreak around the world with a high correlation (r2>0.6) with the real data. Using this model, we further predicted the possible epidemic situation in the future 12 days in several high-latitude cities with potential outbreak. This model could provide more information for government's future decisions on COVID-19 outbreak control.

negative: Identification of potential binders of the main protease 3CL(pro) of the COVID-19 via structure-based ligand design and molecular modeling We have applied a computational strategy, using a combination of virtual screening, docking and molecular dynamics techniques, aimed at identifying possible lead compounds for the non-covalent inhibition of the main protease 3CL(pro) of the SARS-CoV2 Coronavirus. Based on the X-ray structure (PDB code: 6LU7), ligands were generated using a multimodal structure-based design and then docked to the monomer in the active state. Docking calculations show that ligand-binding is strikingly similar in SARS-CoV and SARS-CoV2 main proteases. The most potent docked ligands are found to share a common binding pattern with aromatic moieties connected by rotatable bonds in a pseudo-linear arrangement.

negative: Humoral immunity to human metapneumovirus infection in adults() Human metapneumovirus (hMPV) is a significant cause of respiratory illness in children and adults. Presently, there are no human data regarding the role of antibody for protection against hMPV illness. Therefore, we measured serum and nasal antibody titers against hMPV by EIA and neutralization assay at baseline in hMPV infected adults compared with subjects who remained uninfected. Antibody titers were also compared in patients with mild and severe illness. Mean serum binding and neutralizing antibody titers of hMPV infected subjects were significantly lower compared to uninfected subjects. Seventy-one percent of subjects with titers ≤10.5 (log 2) were infected compared to 36% with titers >10.5, p = 0.003. There was no difference in the mean acute antibody titers for patients with mild compared to severe illness. Serum antibody may play a role in protection from hMPV infection supporting the development of an hMPV vaccine that stimulates humoral immunity.

negative: Risk interactions of coronavirus infection across age groups after the peak of COVID-19 epidemic Background: the COVID-19 epidemic has incurred significant disease burden worldwide, particularly on elderly population. This study aims to explore how risks of infection interact across age groups and compared risk patterns between South Korea and US Florida state. Methods: Daily new COVID-19 cases were scraped from online sources. A multivariate vector autoregressive model for time series count data was used to examine the risk interactions across age groups. Case counts from previous days were included as predictors to dynamically examine the change of risk patterns. Results: In both South Korea and Florida, the risk of coronavirus infection among elderly people was significantly affected by other age groups. An increase of virus infection among people aged 20 -39 could double the risk of infection among elderly people. Meanwhile, an increase in virus infection among elderly people also significantly increased risks of infection among other age groups. The risks of infection among younger people were relatively unaffected by that of other age groups. Conclusions: Protecting elderly people from coronavirus infection could not only reduce the risk of infection among themselves but also ameliorate the risks of virus infection among other age groups. Such interventions should be effective and for long term.

negative: Combination anti-HIV-1 antibody therapy is associated with increased virus-specific T cell immunity Combination antiretroviral therapy (ART) is highly effective in controlling human immunodeficiency virus (HIV)-1 but requires lifelong medication due to the existence of a latent viral reservoir(1,2). Potent broadly neutralizing antibodies (bNAbs) represent a potential alternative or adjuvant to ART. In addition to suppressing viremia, bNAbs may have T cell immunomodulatory effects as seen for other forms of immunotherapy(3). However, this has not been established in individuals who are infected with HIV-1. Here, we document increased HIV-1 Gag-specific CD8(+) T cell responses in the peripheral blood of all nine study participants who were infected with HIV-1 with suppressed blood viremia, while receiving bNAb therapy during ART interruption(4). Increased CD4(+) T cell responses were detected in eight individuals. The increased T cell responses were due both to newly detectable reactivity to HIV-1 Gag epitopes and the expansion of pre-existing measurable responses. These data demonstrate that bNAb therapy during ART interruption is associated with enhanced HIV-1-specific T cell responses. Whether these augmented T cell responses can contribute to bNAb-mediated viral control remains to be determined.

negative: Understand Research Hotspots Surrounding COVID-19 and Other Coronavirus Infections Using Topic Modeling Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a virus that causes severe respiratory illness in humans, which eventually results in the current outbreak of novel coronavirus disease (COVID-19) around the world. The research community is interested to know what are the hotspots in coronavirus (CoV) research and how much is known about COVID-19. This study aimed to evaluate the characteristics of publications involving coronaviruses as well as COVID-19 by using a topic modeling analysis. Methods: We extracted all abstracts and retained the most informative words from the COVID-19 Open Research Dataset, which contains all the 35,092 pieces of coronavirus related literature published up to March 20, 2020. Using Latent Dirichlet Allocation modeling, we trained an eight-topic model from the corpus. We then analyzed the semantic relationships between topics and compared the topic distribution between COVID-19 and other CoV infections. Results: Eight topics emerged overall: clinical characterization, pathogenesis research, therapeutics research, epidemiological study, virus transmission, vaccines research, virus diagnostics, and viral genomics. It was observed that COVID-19 research puts more emphasis on clinical characterization, epidemiological study, and virus transmission at present. In contrast, topics about diagnostics, therapeutics, vaccines, genomics and pathogenesis only accounted for less than 10% or even 4% of all the COVID-19 publications, much lower than those of other CoV infections. Conclusions: These results identified knowledge gaps in the area of COVID-19 and offered directions for future research. Keywords: COVID-19, coronavirus, topic modeling, hotspots, text mining

negative: The current understanding and potential therapeutic options to combat COVID-19 Abstract The ongoing wreaking global outbreak of the novel human beta coronavirus (CoV) pathogen was presumed to be from a seafood wholesale market in Wuhan, China, belongs to the Coronaviridae family in the Nidovirales order. The virus is highly contagious with potential human-human transmission which was named as the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has spread across six continents and emerged as a global pandemic in short span with alarming levels of spread and severity. This virus associated symptoms and infectious respiratory illness is designated as coronavirus disease 19 (COVID-19). The SARS-CoV-2 possesses enveloped club-like spike protein projections with positive-sense large RNA genome and has a unique replication strategy. This virus was believed to have zoonotic origin with genetical identity to bat and pangolin CoV. In the current review, we introduce a general overview about the human CoVs and the associated diseases, the origin, structure, replication and key clinical events that occur in the COVID-19 pathogenicity. Furthermore, we focused on possible therapeutic options such as repurposing drugs including antimalarials, antivirals, antiparasitic drugs, and anti-HIV drugs, as well as monoclonal antibodies, vaccines as potential treatment options. Also we have summarized the latest research progress on the usage of stem cell therapy, human convalescent serum, interferon's, in the treatment of COVID-19.

negative: Growth and Quantification of MERS-CoV Infection Middle East respiratory syndrome coronavirus (MERS-CoV) is an emerging highly pathogenic respiratory virus. Although MERS-CoV only emerged in 2012, we and others have developed assays to grow and quantify infectious MERS-CoV and RNA products of replication in vitro. MERS-CoV is able to infect a range of cell types, but replicates to high titers in Vero E6 cells. Protocols for the propagation and quantification of MERS-CoV are presented.

negative: Do checkpoint inhibitors compromise the cancer patients’ immunity and increase the vulnerability to COVID-19 infection? The severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) has been declared a pandemic by the WHO that claimed the lives of thousands of people within a few months. Cancer patients represent a vulnerable population due to the acquired immunodeficiency associated with anti-cancer therapy. Immune checkpoint inhibitors have largely impacted the prognosis of a multitude of malignancies with significant improvement in survival outcomes and a different, tolerable toxicity profile. In this paper, we assess the safety of ICI administration in cancer patients during the coronavirus pandemic in order to guide the usage of these highly efficacious agents.

negative: Understanding Fc Receptor Involvement in Inflammatory Diseases: From Mechanisms to New Therapeutic Tools Fc receptors (FcRs) belong to the ITAM-associated receptor family. FcRs control the humoral and innate immunity which are essential for appropriate responses to infections and prevention of chronic inflammation or auto-immune diseases. Following their crosslinking by immune complexes, FcRs play various roles such as modulation of the immune response by released cytokines or of phagocytosis. Here, we review FcR involvement in pathologies leading notably to altered intracellular signaling with functionally relevant consequences to the host, and targeting of Fc receptors as therapeutic approaches. Special emphasis will be given to some FcRs, such as the FcαRI, the FcγRIIA and the FcγRIIIA, which behave like the ancient god Janus depending on the ITAM motif to inhibit or activate immune responses depending on their targeting by monomeric/dimeric immunoglobulins or by immune complexes. This ITAM duality has been recently defined as inhibitory or activating ITAM (ITAMi or ITAMa) which are controlled by Src family kinases. Involvement of various ITAM-bearing FcRs observed during infectious or autoimmune diseases is associated with allelic variants, changes in ligand binding ability responsible for host defense perturbation. During auto-immune diseases such as rheumatoid arthritis, lupus or immune thrombocytopenia, the autoantibodies and immune complexes lead to inflammation through FcR aggregation. We will discuss the role of FcRs in autoimmune diseases, and focus on novel approaches to target FcRs for resolution of antibody-mediated autoimmunity. We will finally also discuss the down-regulation of FcR functionality as a therapeutic approach for autoimmune diseases.

negative: Point-of-care testing for community-acquired pneumonia

negative: MERS-CoV: transmisión y el papel de nuevas especies hospederas

negative: Molecular and serological investigation of 2019-nCoV infected patients: implication of multiple shedding routes In December 2019, a novel coronavirus (2019-nCoV) caused an outbreak in Wuhan, China, and soon spread to other parts of the world. It was believed that 2019-nCoV was transmitted through respiratory tract and then induced pneumonia, thus molecular diagnosis based on oral swabs was used for confirmation of this disease. Likewise, patient will be released upon two times of negative detection from oral swabs. However, many coronaviruses can also be transmitted through oral–fecal route by infecting intestines. Whether 2019-nCoV infected patients also carry virus in other organs like intestine need to be tested. We conducted investigation on patients in a local hospital who were infected with this virus. We found the presence of 2019-nCoV in anal swabs and blood as well, and more anal swab positives than oral swab positives in a later stage of infection, suggesting shedding and thereby transmitted through oral–fecal route. We also showed serology test can improve detection positive rate thus should be used in future epidemiology. Our report provides a cautionary warning that 2019-nCoV may be shed through multiple routes.

negative: [Strategies for vaccine development of COVID-19] An epidemic of acute respiratory syndrome in humans, which appeared in Wuhan, China in December 2019, was caused by a novel coronavirus (SARS-CoV-2). This disease was named as "Coronavirus Disease 2019" (COVID-19). SARS-CoV-2 was first identified as an etiological pathogen of COVID-19, belonging to the species of severe acute respiratory syndrome-related coronaviruses (SARSr-CoV). The speed of both the geographical transmission and the sudden increase in numbers of cases is much faster than SARS and Middle East respiratory syndrome (MERS). COVID-19 is the first global pandemic caused by a coronavirus, which outbreaks in 211 countries/territories/areas. The vaccine against COVID-19, regarded as an effective prophylactic strategy for control and prevention, is being developed in about 90 institutions worldwide. The experiences and lessons encountered in the previous SARS and MERS vaccine research can be used for reference in the development of COVID-19 vaccine. The present paper hopes to provide some insights for COVID-19 vaccines researchers.

negative: Genetic deletion of Sphk2 confers protection against Pseudomonas aeruginosa mediated differential expression of genes related to virulent infection and inflammation in mouse lung BACKGROUND: Pseudomonas aeruginosa (PA) is an opportunistic Gram-negative bacterium that causes serious life threatening and nosocomial infections including pneumonia. PA has the ability to alter host genome to facilitate its invasion, thus increasing the virulence of the organism. Sphingosine-1- phosphate (S1P), a bioactive lipid, is known to play a key role in facilitating infection. Sphingosine kinases (SPHK) 1&2 phosphorylate sphingosine to generate S1P in mammalian cells. We reported earlier that Sphk2(−/−) mice offered significant protection against lung inflammation, compared to wild type (WT) animals. Therefore, we profiled the differential expression of genes between the protected group of Sphk2(−/−) and the wild type controls to better understand the underlying protective mechanisms related to the Sphk2 deletion in lung inflammatory injury. Whole transcriptome shotgun sequencing (RNA-Seq) was performed on mouse lung tissue using NextSeq 500 sequencing system. RESULTS: Two-way analysis of variance (ANOVA) analysis was performed and differentially expressed genes following PA infection were identified using whole transcriptome of Sphk2(−/−) mice and their WT counterparts. Pathway (PW) enrichment analyses of the RNA seq data identified several signaling pathways that are likely to play a crucial role in pneumonia caused by PA such as those involved in: 1. Immune response to PA infection and NF-κB signal transduction; 2. PKC signal transduction; 3. Impact on epigenetic regulation; 4. Epithelial sodium channel pathway; 5. Mucin expression; and 6. Bacterial infection related pathways. Our genomic data suggests a potential role for SPHK2 in PA-induced pneumonia through elevated expression of inflammatory genes in lung tissue. Further, validation by RT-PCR on 10 differentially expressed genes showed 100% concordance in terms of vectoral changes as well as significant fold change. CONCLUSION: Using Sphk2(−/−) mice and differential gene expression analysis, we have shown here that S1P/SPHK2 signaling could play a key role in promoting PA pneumonia. The identified genes promote inflammation and suppress others that naturally inhibit inflammation and host defense. Thus, targeting SPHK2/S1P signaling in PA-induced lung inflammation could serve as a potential therapy to combat PA-induced pneumonia.

negative: Development of a Novel, Genome Subtraction-Derived, SARS-CoV-2-Specific COVID-19-nsp2 Real-Time RT-PCR Assay and Its Evaluation Using Clinical Specimens The pandemic novel coronavirus infection, Coronavirus Disease 2019 (COVID-19), has affected at least 190 countries or territories, with 465,915 confirmed cases and 21,031 deaths. In a containment-based strategy, rapid, sensitive and specific testing is important in epidemiological control and clinical management. Using 96 SARS-CoV-2 and 104 non-SARS-CoV-2 coronavirus genomes and our in-house program, GolayMetaMiner, four specific regions longer than 50 nucleotides in the SARS-CoV-2 genome were identified. Primers were designed to target the longest and previously untargeted nsp2 region and optimized as a probe-free real-time reverse transcription-polymerase chain reaction (RT-PCR) assay. The new COVID-19-nsp2 assay had a limit of detection (LOD) of 1.8 TCID(50)/mL and did not amplify other human-pathogenic coronaviruses and respiratory viruses. Assay reproducibility in terms of cycle threshold (Cp) values was satisfactory, with the total imprecision (% CV) values well below 5%. Evaluation of the new assay using 59 clinical specimens from 14 confirmed cases showed 100% concordance with our previously developed COVID-19-RdRp/Hel reference assay. A rapid, sensitive, SARS-CoV-2-specific real-time RT-PCR assay, COVID-19-nsp2, was developed.

negative: 2019-nCoV: The Identify-Isolate-Inform (3I) Tool Applied to a Novel Emerging Coronavirus 2019 Novel Coronavirus (2019-nCoV) is an emerging infectious disease closely related to MERS-CoV and SARS-CoV that was first reported in Wuhan City, Hubei Province, China in December 2019. As of January 2020, cases of 2019-nCoV are continuing to be reported in other Eastern Asian countries as well as in the United States, Europe, Australia, and numerous other countries. An unusually high volume of domestic and international travel corresponding to the beginning of the 2020 Chinese New Year complicated initial identification and containment of infected persons. Due to the rapidly rising number of cases and reported deaths, all countries should be considered at risk of imported 2019-nCoV. Therefore, it is essential for prehospital, clinic, and emergency department personnel to be able to rapidly assess 2019-nCoV risk and take immediate actions if indicated. The Identify-Isolate-Inform (3I) Tool, originally conceived for the initial detection and management of Ebola virus and later adjusted for other infectious agents, can be adapted for any emerging infectious disease. This paper reports a modification of the 3I Tool for use in the initial detection and management of patients under investigation for 2019-nCoV. After initial assessment for symptoms and epidemiological risk factors, including travel to affected areas and exposure to confirmed 2019-nCoV patients within 14 days, patients are classified in a risk-stratified system. Upon confirmation of a suspected 2019-nCoV case, affected persons must immediately be placed in airborne infection isolation and the appropriate public health agencies notified. This modified 3I Tool will assist emergency and primary care clinicians, as well as out-of-hospital providers, in effectively managing persons with suspected or confirmed 2019-nCoV.

negative: Strong evolutionary convergence of receptor-binding protein spike between COVID-19 and SARS-related coronaviruses Coronavirus Disease 2019 (COVID-19) and severe acute respiratory syndrome (SARS)-related coronaviruses (e.g., 2019-nCoV and SARS-CoV) are phylogenetically distantly related, but both are capable of infecting human hosts via the same receptor, angiotensin-converting enzyme 2, and cause similar clinical and pathological features, suggesting their phenotypic convergence. Yet, the molecular basis that underlies their phenotypic convergence remains unknown. Here, we used a recently developed molecular phyloecological approach to examine the molecular basis leading to their phenotypic convergence. Our genome-level analyses show that the spike protein, which is responsible for receptor binding, has undergone significant Darwinian selection along the branches related to 2019-nCoV and SARS-CoV. Further examination shows an unusually high proportion of evolutionary convergent amino acid sites in the receptor binding domain (RBD) of the spike protein between COVID-19 and SARS-related CoV clades, leading to the phylogenetic uniting of their RBD protein sequences. In addition to the spike protein, we also find the evolutionary convergence of its partner protein, ORF3a, suggesting their possible co-evolutionary convergence. Our results demonstrate a strong adaptive evolutionary convergence between COVID-19 and SARS-related CoV, possibly facilitating their adaptation to similar or identical receptors. Finally, it should be noted that many observed bat SARS-like CoVs that have an evolutionary convergent RBD sequence with 2019-nCoV and SARS-CoV may be pre-adapted to human host receptor ACE2, and hence would be potential new coronavirus sources to infect humans in the future.

negative: Determination of daily reproduction numbers of SARS-CoV2 based on death cases suggests more rapid initial spread in Italy and the United States Population density, behaviour and cultural habits strongly influence the spread of pathogens. Consequently, key epidemiological parameters may vary from country to country. Confirmed COVID-19 cases in in China have been used to estimate those parameters, that vary largely (reviewed in 1). The estimates also depend on testing frequency and case definitions that are prone to change during ongoing epidemics, providing additional uncertainties. The rise in fatal cases due to SARS-CoV2 could be a more reliable parameter, since missing of deaths is less likely. In the absence of changes in the management of severe COVID-19 cases, the rise in death cases should be proportional to the rise in virus infections. Although the fluctuating low numbers of fatal cases very early in the epidemic may lead to some uncertainty, more than 100 deaths per day are reported since 10.03.2020 in Italy and since 21.03.2020 in the US. Therefore, the dynamics of deaths were analysed to estimate the daily reproduction numbers (Rt) and the effectiveness of control measures. Thus, our analysis provides evidence that basic epidemiological parameters differ between countries to an extent compromising epidemiological predictions of the pandemic. It also suggests that suppression of spread in Italy and the US may be more difficult to achieve. Although we assume that variations in social behaviour are responsible for the different estimates of R0, selection of more rapidly spreading variants of SARS-CoV-2 cannot be excluded. Despite uncertainty in the reliability of the data used and lack of information on possible changes in the effectiveness of registration of COVID-19 deaths during the observation period, our findings should be considered as a working hypothesis demanding further investigations. As the number of deaths rapidly increases worldwide, we encourage more sophisticated modelling of the epidemic based on the dynamics of death cases by experts in the field.

negative: Using statistics and mathematical modelling to understand infectious disease outbreaks: COVID-19 as an example During an infectious disease outbreak, biases in the data and complexities of the underlying dynamics pose significant challenges in mathematically modelling the outbreak and designing policy. Motivated by the ongoing response to COVID-19, we provide a toolkit of statistical and mathematical models beyond the simple SIR-type differential equation models for analysing the early stages of an outbreak and assessing interventions. In particular, we focus on parameter estimation in the presence of known biases in the data, and the effect of non-pharmaceutical interventions in enclosed subpopulations, such as households and care homes. We illustrate these methods by applying them to the COVID-19 pandemic.

negative: Serological and molecular findings during SARS-CoV-2 infection: the first case study in Finland, January to February 2020 The first case of coronavirus disease (COVID-19) in Finland was confirmed on 29 January 2020. No secondary cases were detected. We describe the clinical picture and laboratory findings 3–23 days since the first symptoms. The SARS-CoV-2/Finland/1/2020 virus strain was isolated, the genome showing a single nucleotide substitution to the reference strain from Wuhan. Neutralising antibody response appeared within 9 days along with specific IgM and IgG response, targeting particularly nucleocapsid and spike proteins.

negative: Informational needs assessment of non‐Hodgkin lymphoma survivors and their physicians

negative: Swine acute diarrhea syndrome coronavirus (SADS-CoV) antagonizes interferon-ß production via blocking IPS-1 and RIG-I Swine acute diarrhea syndrome coronavirus (SADS-CoV), a newly emerging enteric coronavirus, is considered to be associated with swine acute diarrhea syndrome (SADS) which has caused significantly economic losses to the porcine industry. Interactions between SADS-CoV and the host innate immune response is unclear yet. In this study, we used IPEC-J2 cells as a model to explore potential evasion strategies employed by SADS-CoV. Our results showed that SADS-CoV infection failed to induce IFN-ß production, and inhibited poly (I:C) and Sendai virus (SeV)-triggered IFN-ß expression. SADS-CoV also blocked poly (I:C)-induced phosphorylation and nuclear translocation of IRF-3 and NF-κB. Furthermore, SADS-CoV did not interfere with the activity of IFN-ß promoter stimulated by IRF3, TBK1 and IKKÎµ, but counteracted its activation induced by IPS-1 and RIG-I. Collectively, this study is the first investigation that shows interactions between SADS-CoV and the host innate immunity, which provides information of the molecular mechanisms underlying SASD-CoV infection.

negative: National Institute for the Infectious Diseases “L. Spallanzani”, IRCCS. Recommendations for COVID-19 clinical management On January 9 2020, the World Health Organization (WHO) declared the identification, by Chinese Health authorities, of a novel coronavirus, further classified as SARS-CoV-2 responsible of a disease (COVID-19) ranging from asymptomatic cases to severe respiratory involvement. On March 9 2020, WHO declared COVID-19 a global pandemic. Italy is the second most affected country by COVID-19 infection after China. The “L. Spallanzani” National Institute for the Infectious Diseases, IRCCS, Rome, Italy, has been the first Italian hospital to admit and manage patients affected by COVID-19. Hereby, we show our recommendations for the management of COVID-19 patients, based on very limited clinical evidences; they should be considered as expert opinions, which may be modified according to newly produced literature data.

negative: Optimized pseudotyping conditions for the SARS-COV2 Spike glycoprotein The SARS-COV2 Spike glycoprotein is solely responsible for binding to the host cell receptor and facilitating fusion between the viral and host membranes. The ability to generate viral particles pseudotyped with SARS-COV2 Spike is useful for many types of studies, such as characterization of neutralizing antibodies or development of fusion-inhibiting small molecules. Here we characterized the use of a codon-optimized SARS-COV2 Spike glycoprotein for the generation of pseudotyped HIV-1, MLV, and VSV particles. The full-length Spike protein functioned inefficiently with all three systems but was enhanced over 10-fold by deleting the last 19 amino acids of the cytoplasmic tail of Spike. Infection of 293FT target cells was only possible if the cells were engineered to stably express the human ACE-2 receptor, but stably introducing an additional copy of this receptor did not further enhance susceptibility. Stable introduction of the Spike activating protease TMPRSS2 further enhanced susceptibility to infection by 5-10 fold. Substitution of the signal peptide of the Spike protein with an optimal signal peptide did not enhance or reduce infectious particle production. However, modification of a single amino acid in the furin cleavage site of Spike (R682Q) enhanced infectious particle production another 10-fold. With all enhancing elements combined, the titer of pseudotyped particles reached almost 106 infectious particles/ml. Finally, HIV-1 particles pseudotyped with SARS-COV2 Spike was successfully used to detect neutralizing antibodies in plasma from COVID-19 patients, but not plasma from uninfected individuals. Importance When working with pathogenic viruses, it is useful to have rapid quantitative tests for viral infectivity that can be performed without strict biocontainment restrictions. A common way of accomplishing this is to generate viral pseudoparticles that contain the surface glycoprotein from the pathogenic virus incorporated into a replication-defective viral particle that contains a sensitive reporter system. These pseudoparticles enter cells using the glycoprotein from the pathogenic virus leading to a readout for infection. Conditions that block entry of the pathogenic virus, such as neutralizing antibodies, will also block entry of the viral pseudoparticles. However, viral glycoproteins often are not readily suited for generating pseudoparticles. Here we describe a series of modifications that result in the production of relatively high titer SARS-COV2 pseudoparticles that are suitable for detection of neutralizing antibodies from COVID-19 patients.

negative: The RNA Virus Database http://virus.zoo.ox.ac.uk/rnavirusdb; http://hivweb.sanbi.ac.za/rnavirusdb; http://bioinf.cs.auckland.ac.nz/rnavirusdb; http://tree.bio.ed.ac.uk/rnavirusdb.

negative: MERS-CoV as an emerging respiratory illness: A review of prevention methods Abstract Introduction Middle East Respiratory Coronavirus Virus (MERS-CoV) first emerged from Saudi Arabia in 2012 and has since been recognized as a significant human respiratory pathogen on a global level. Methods In this narrative review, we focus on the prevention of MERS-CoV. We searched PubMed, Embase, Cochrane, Scopus, and Google Scholar, using the following terms: ‘MERS’, ‘MERS-CoV’, ‘Middle East respiratory syndrome’ in combination with ‘prevention’ or ‘infection control’. We also reviewed the references of each article to further include other studies or reports not identified by the search. Results As of Nov 2019, a total of 2468 laboratory-confirmed cases of MERS-CoV were diagnosed mostly from Middle Eastern regions with a mortality rate of at least 35%. A major outbreak that occurred outside the Middle East (in South Korea) and infections reported from 27 countries. MERS-CoV has gained recognition as a pathogen of global significance. Prevention of MERS-CoV infection is a global public health priority. Healthcare facility transmission and by extension community transmission, the main amplifier of persistent outbreaks, can be prevented through early identification and isolation of infected humans. While MERS-CoV vaccine studies were initially hindered by multiple challenges, recent vaccine development for MERS-CoV is showing promise. Conclusions The main factors leading to sustainability of MERS-CoV infection in high risk courtiers is healthcare facility transmission. MERS-CoV transmission in healthcare facility mainly results from laps in infection control measures and late isolation of suspected cases. Preventive measures for MERS-CoV include disease control in camels, prevention of camel to human transmission.

negative: Lactogenic immunity in transgenic mice producing recombinant antibodies neutralizing coronavirus. Protection against coronavirus infections can be provided by the oral administration of virus neutralizing antibodies. To provide lactogenic immunity, eighteen lines of transgenic mice secreting a recombinant IgG1 monoclonal antibody (rIgG1) and ten lines of transgenic mice secreting recombinant IgA monoclonal antibodies (rIgA) neutralizing transmissible gastroenteritis coronavirus (TGEV) into the milk were generated. Genes encoding the light and heavy chains of monoclonal antibody (MAb) 6A.C3 were expressed under the control of regulatory sequences derived from the mouse genomic DNA encoding the whey acidic protein (WAP) and beta-lactoglobulin (BLG), which are highly abundant milk proteins. The MAb 6A.C3 binds to a highly conserved epitope present in coronaviruses of several species. This MAb does not allow the selection of neutralization escaping virus mutants. The antibody was expressed in the milk of transgenic mice with titers of one million as determined by RIA, and neutralized TGEV infectivity by one million fold corresponding to immunoglobulin concentrations of 5 to 6 mg per ml. Matrix attachment regions (MAR) sequences were not essential for rIgG1 transgene expression, but co-microinjection of MAR and antibody genes led to a twenty to ten thousand-fold increase in the antibody titer in 50% of the rIgG1 transgenic animals generated. Co-microinjection of the genomic BLG gene with rIgA light and heavy chain genes led to the generation of transgenic mice carrying the three transgenes. The highest antibody titers were produced by transgenic mice that had integrated the antibody and BLG genes, although the number of transgenic animals generated does not allow a definitive conclusion on the enhancing effect of BLG co-integration. Antibody expression levels were transgene copy number independent and integration site dependent. The generation of transgenic animals producing virus neutralizing antibodies in the milk could be a general approach to provide protection against neonatal infections of the enteric tract.

negative: Network-based drug repurposing for novel coronavirus 2019-nCoV/SARS-CoV-2 Human coronaviruses (HCoVs), including severe acute respiratory syndrome coronavirus (SARS-CoV) and 2019 novel coronavirus (2019-nCoV, also known as SARS-CoV-2), lead global epidemics with high morbidity and mortality. However, there are currently no effective drugs targeting 2019-nCoV/SARS-CoV-2. Drug repurposing, representing as an effective drug discovery strategy from existing drugs, could shorten the time and reduce the cost compared to de novo drug discovery. In this study, we present an integrative, antiviral drug repurposing methodology implementing a systems pharmacology-based network medicine platform, quantifying the interplay between the HCoV–host interactome and drug targets in the human protein–protein interaction network. Phylogenetic analyses of 15 HCoV whole genomes reveal that 2019-nCoV/SARS-CoV-2 shares the highest nucleotide sequence identity with SARS-CoV (79.7%). Specifically, the envelope and nucleocapsid proteins of 2019-nCoV/SARS-CoV-2 are two evolutionarily conserved regions, having the sequence identities of 96% and 89.6%, respectively, compared to SARS-CoV. Using network proximity analyses of drug targets and HCoV–host interactions in the human interactome, we prioritize 16 potential anti-HCoV repurposable drugs (e.g., melatonin, mercaptopurine, and sirolimus) that are further validated by enrichment analyses of drug-gene signatures and HCoV-induced transcriptomics data in human cell lines. We further identify three potential drug combinations (e.g., sirolimus plus dactinomycin, mercaptopurine plus melatonin, and toremifene plus emodin) captured by the “Complementary Exposure” pattern: the targets of the drugs both hit the HCoV–host subnetwork, but target separate neighborhoods in the human interactome network. In summary, this study offers powerful network-based methodologies for rapid identification of candidate repurposable drugs and potential drug combinations targeting 2019-nCoV/SARS-CoV-2.

negative: Current status of potential therapeutic candidates for the COVID-19 crisis Abstract As of April 15, 2020, the ongoing coronavirus disease 2019 (COVID-2019) pandemic has swept through 213 countries and infected more than 1,870,000 individuals, posing an unprecedented threat to international health and the economy. There is currently no specific treatment available for patients with COVID-19 infection. The lessons learned from past management of respiratory viral infections have provided insights into treating COVID-19. Numerous potential therapies, including supportive intervention, immunomodulatory agents, antiviral therapy, and convalescent plasma transfusion, have been tentatively applied in clinical settings. A number of these therapies have provided substantially curative benefits in treating patients with COVID-19 infection. Furthermore, intensive research and clinical trials are underway to assess the efficacy of existing drugs and identify potential therapeutic targets to develop new drugs for treating COVID-19. Herein, we summarize the current potential therapeutic approaches for diseases related to COVID-19 infection and introduce their mechanisms of action, safety, and effectiveness.

negative: SARS-CoV-2 in the ocular surface of COVID-19 patients The 2019 novel coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread globally, while the routes of transmission of this virus are still controversial. We enrolled 33 patients, without any ocular manifestation, with their ocular surface swabs collected for virus detection. RNA was detected strong positive in samples of both eyes from two patients. Therefore, SARS-CoV-2 may exist in the normal ocular surface of COVID-19 patients, suggesting that this virus might be spread through conjunctival contact.

negative: Ebselen as a highly active inhibitor of PLProCoV2 Since December 2019 a novel a coronavirus identified as SARS-CoV-2 or COV2 has been spreading around the world. On the 16th of May around 4.5 million people got infected and over 300,000 died due to the infection of COV2. The effective treatment remains a challenge. Targeted therapeutics are still under investigation. The papain-like protease (PLPro) from the human SARS-CoV-2 coronavirus is a cysteine protease that plays a critical role in virus replication. Its activity is required to process the viral polyprotein into functional, mature subunits. Moreover, COV2 uses this enzyme to modulate the host’s immune system to its own benefit. Therefore, it represents a highly promising target for the development of antiviral drugs. In this work, we discovered that ebselen, a synthetic organoselenium drug molecule with anti-inflammatory, anti-oxidant and cytoprotective activity in mammalian cells and cytotoxicity in lower organisms, is a highly active inhibitor of PLProCoV2. We proved that ebselen is a covalent, fast-binding inhibitor of PLProCoV2 exhibiting a low micromolar potency. Furthermore, we identified a difference between PLPro from SARS-CoV-1 (the corona virus which caused the 2002–2004 outbreak, SARS) and SARS-CoV-2 that allows to explain the difference in dynamics of the replication, and, thus, the disease progression. Namely, we present that they show differences in the binding affinity of substrates that we observed through kinetics and molecular docking studies. Using a novel Approximate Bayesian Computation method we were able to find kinetic constants for both enzymes. Molecular modeling study on the structure of the active site and binding mode of the ebselen with SARS and COV2 showed also significant differences that could explain our observation that ebselen is less active and slower bounding with SARS than COV2. In conclusion, we show that ebselen inhibits the activity of the essential viral enzyme papain-like protease (PLpro) from SARS-COV-2 in low micromolar range.

negative: Unveiling the roles of autophagy in innate and adaptive immunity Cells digest portions of their interiors in a process known as autophagy to recycle nutrients, remodel and dispose of unwanted cytoplasmic constituents. This ancient pathway, conserved from yeast to humans, is now emerging as a central player in the immunological control of bacterial, parasitic and viral infections. The process of autophagy may degrade intracellular pathogens, deliver endogenous antigens to MHC-class-II-loading compartments, direct viral nucleic acids to Toll-like receptors and regulate T-cell homeostasis. This Review describes the mechanisms of autophagy and highlights recent advances relevant to the role of autophagy in innate and adaptive immunity.

negative: COVID-19 and immigration detention in the USA: time to act

negative: Comparative analysis of non structural protein 1 of SARS-COV2 with SARS-COV1 and MERS-COV: An in silico study The recently emerged SARS-COV2 caused a major pandemic of coronavirus disease (COVID-19). The main goal of this study is to elucidate the structural conformations of non structural protein 1(nsp1), prediction of epitope sites and identification of important residues for targeted therapy against COVID-19. In this study, molecular modelling coupled with molecular dynamics simulations were performed to analyse the conformational change of SARS-COV1, SARS-COV2 and MERS-COV at molecular level. Free energy landscape was constructed by using the first (PC1) and second (PC2) principle components. From the sequence alignment it was observed when compared to SERS-COV1 28 mutations are present in SERS-COV2 nsp1 protein. Several B-cell and T-cell epitopes were identified by immunoinformatics study. The ΔG values for SARS-COV1, SARS-COV2 and MERS-COV nsp1 proteins were 4.44, 5.82 and 6.15 kJ/mol respectively. SARS-COV2 nsp1 protein binds with the interface region of the palm and finger domain of POLA1 by using hydrogen bonds and salt bridges interactions. The present study provided a comprehensive structural model of nsp1 by threading process. The MD simulation parameters indicated that all three nsp1 proteins were stable during the simulation run. These findings can be used to develop therapeutics specific against COVID-19. Highlights Structural elucidation at molecular level of nsp1 of SARS-COV1, SARS-COV2, and MERS-COV Identifications of epitopes by immunoinformatics approach SARS-COV2 nsp1 cover a large conformational space due to greater flexibility Molecular docking between SARS-COV2 nsp1 and POLA1 to identify important residues Structural insights of nsp1 could be used in drug design process against COVID-19 Graphical abstract

negative: Human monoclonal antibodies for prophylaxis and therapy of viral infections

negative: Development of an inactivated vaccine candidate for SARS-CoV-2 The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in an unprecedented public health crisis. Because of the novelty of the virus, there are currently no SARS-CoV-2-specific treatments or vaccines available. Therefore, rapid development of effective vaccines against SARS-CoV-2 are urgently needed. Here, we developed a pilot-scale production of PiCoVacc, a purified inactivated SARS-CoV-2 virus vaccine candidate, which induced SARS-CoV-2-specific neutralizing antibodies in mice, rats, and nonhuman primates. These antibodies neutralized 10 representative SARS-CoV-2 strains, suggesting a possible broader neutralizing ability against other strains. Three immunizations using two different doses, 3 or 6 micrograms per dose, provided partial or complete protection in macaques against SARS-CoV-2 challenge, respectively, without observable antibody-dependent enhancement of infection. These data support the clinical development and testing of PiCoVacc for use in humans.

negative: Cytokine storm intervention in the early stages of COVID-19 pneumonia Abstract Clinical intervention in patients with corona virus disease 2019 (COVID-19) has demonstrated a strong upregulation of cytokine production in patients who are critically ill with SARS-CoV2-induced pneumonia. In a retrospective study of 41 patients with COVID-19, most patients with SARS-CoV-2 infection developed mild symptoms, whereas some patients later developed aggravated disease symptoms, and eventually passed away because of multiple organ dysfunction syndrome (MODS), as a consequence of a severe cytokine storm. Guidelines for the diagnosis and treatment of SARS-CoV-2 infected pneumonia were first published January 30th, 2020; these guidelines recommended for the first time that cytokine monitoring should be applied in severely ill patients to reduce pneumonia related mortality. The cytokine storm observed in COVID-19 illness is also an important component of mortality in other viral diseases, including SARS, MERS and influenza. In view of the severe morbidity and mortality of COVID-19 pneumonia, we review the current understanding of treatment of human coronavirus infections from the perspective of a dysregulated cytokine and immune response.

negative: Proposing a fungal metabolite-Flaviolin as a potential inhibitor of 3CLpro of novel coronavirus SARS-CoV2 using docking and molecular dynamics Here after performing docking and molecular dynamics of various small molecules derived as a secondary metabolite from fungi, we propose Flaviolin to act as potent inhibitor of 3-chymotrypsin (3C) like protease (3CLpro) of noval corona virus SARS-CoV2 responsible for pandemic condition caused by coronavirus disease 2019 (COVID-19).

negative: Population implications of the deployment of novel universal vaccines against epidemic and pandemic influenza There is increasing interest in the development of new, ‘universal’ influenza vaccines (UIVs) that––unlike current vaccines––are effective against a broad range of seasonal influenza strains, as well as against novel pandemic viruses. While the existing literature discusses the potential epidemiological benefits of UIVs, it is also important to anticipate their potential unintended population consequences. Using mathematical modelling, we illustrate two such types of adverse consequences. First, by reducing the amount of infection-induced immunity in a population without fully replacing it, a seasonal UIV programme may permit larger pandemics than in the absence of vaccination. Second, the more successful a future UIV programme is in reducing transmission of seasonal influenza, the more vulnerable the population could become to the emergence of a vaccine escape variant. These risks could be mitigated by optimal deployment of any future UIV vaccine: namely, the use of a combined vaccine formulation (incorporating conventional as well as multiple universal antigenic targets) and achieving sufficient population coverage to compensate for any reductions in infection-induced immunity. In the absence of large-scale trials of UIVs, disease-dynamic models can provide helpful, early insights into their potential impact. In future, data from continuing vaccine development will be invaluable in developing robustly predictive modelling approaches.

negative: Immunodepletion with Hypoxemia: A Potential High Risk Subtype of Coronavirus Disease 2019 Background The outbreak of COVID-2019 is becoming a global public health emergency. Although its basic clinical features have been reported, the dynamic characteristics of immune system in COVID-2019 patients, especially those critical patients with refractory hypoxemia, are not yet well understood. We aim to describe the dynamic characteristics of immune system in 3 critical patients with refractory hypoxemia, and discuss the relationship between hypoxemia severity and immune cell levels, and the changes of gut microbes of COVID-2019 patient. Methods This is a retrospective study from 3 patients with 2019-nCoV infection admitted to Renmin Hospital of Wuhan University, a COVID-2019 designated hospital in Wuhan, from January 31 to February 6, 2020. All patients were diagnosed and classified based on the Diagnosis and Treatment of New Coronavirus Pneumonia (6th edition) published by the National Health Commission of China4. We recorded the epidemiological history, demographic features, clinical characteristics, symptoms and signs, treatment and clinical outcome in detail. Blood samples were collected and we determined the expression levels of immune cells (CD3+ T cells, CD4+ T cells, CD8+ T cells, CD19+ B cells, and CD16+56+ NK cells) in different time points. Nanopore Targeted Sequencing was used to determine the alterations of gut microbiota homeostasis. Results Apart from the clinical features described previously4, we found that four patients had decreased immune cells and refractory hypoxemia during the hospitalization, and the severity of hypoxemia was strongly correlated to the expression levels of immune cells. Additionally, we found that the proportion of probiotics was significantly reduced, such as Bifidobacterium, Lactobacillus, and Eubacterium, and the proportion of conditioned pathogenic bacteria was significantly increased, such as Corynebacterium of Actinobacteria and Ruthenibacterium of Firmicutes. Notably, all patients died. Conclusions We discussed the dynamic characteristics of host immune system and the imbalance of gut microbiota in 3 critical patients with COVID-2019. Hypoxemia severity was closely related with host immune cell levels, and the vicious circle between immune disorder and gut microbiota imbalance may be a high risk of fatal pneumonia. To the best of our knowledge, this is the first study which revealing that immunodepletion with refractory hypoxemia is a potential high risk subtype of COVID-2019 and the vicious circle between immune disorder and gut dysbiosis may be a high risk of fatal pneumonia.

negative: SARS‐CoV‐2 and Multiple Sclerosis: Not All Immune Depleting DMTs are Equal or Bad A major concern during the current severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic1 is the use of immunosuppressive therapies for the treatment of multiple sclerosis (MS) due to an increased risk of contracting SARS-CoV-2 and more severe disease. The Society of Italian Neurologists (SIN) and the Association of British Neurologists (ABN) MS and Neuroimmunology Advisory Group published guidance for the use of current disease modifying treatments (DMTs) in MS (Table 1)2 . However, taking into account, less conservative viewpoints3 , the emerging knowledge of the biology of SARS-CoV-2, and in particular the role of the immune mechanisms contributing to the disease, we propose modification of these guidelines since it is not clear that immunosuppression is indeed detrimental in people with MS infected with SARS-CoV-2. We are thus proposing a more nuanced approach and that the categories of DMTs should be modified based on scientific principles and the biology of severe COVID-19 (Table 2). This article is protected by copyright. All rights reserved.

negative: Increased susceptibility of SARS-CoV2 infection on Oral Cancer patients; Cause and effects: An Hypothesis In 2019, a new coronavirus (SARS CoV2) infecting Humans has emerged in Wuhan, China which caused an unprecedented pandemic involving at least 185 countries infecting 2.5 million people till date. This virus is transmitted directly or indirectly through the upper aerodigestive tract. As it is evident from the recent studies that SARS-CoV-2 requires host enzyme Furin to activate receptor binding domain of its S protein and host Angiotensin Convertase Enzyme 2 (ACE2) is required as binding receptor, facilitating the entry of virus into the host cell. Evidence from literature shows that oral cancer tissues as well as paracarcinoma tissue exhibit higher expression of both Furin and ACE2, giving rise to the hypothesis that patients with oral cancer have higher chances of SARS CoV2 infection. It is also hypothesised that there will be increased severity of disease due to facilitated entry of the virus into the cells. Therefore, we suggest oral cancer patients require extra attention during COVID-19 pandemic and re-evaluation of current treatment paradigms in oral oncology is also needed.

negative: Mucosal immunisation and immunoprophylaxis as potential strategies for prevention of SARS

negative: The amount of cytokine-release defines different shades of Sars-Cov2 infection. The recent outbreak of coronavirus disease (COVID 19), spreading from China all around the world in early 2020, has led scientists to investigate the immuno-mediated mechanisms underlying the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV2) infection. Depending on the amount of cytokines released as the result of the immunological activation induced by SARS-CoV2, three major clinical phenotypes can be identified: "mild",symbolized as a "drizzle" of cytokines, severe as a "storm", and critical as a "hurricane". In patients with mild symptoms, the release of pro-inflammatory cytokines is balanced to obtain a defense response against the virus which is often self-limiting and overcomes without tissue damage. In severe phenotype, resembling a "cytokine-release syndrome", SARS-CoV2 causes the lysis of the immune-mediators leading to a cytokine storm able to induce lung epithelium damage and acute respiratory distress syndrome. In critical patients, the immune response may become uncontrolled, thus the cytokine burst resembles a form of secondary hemophagocytic lymphohistiocytosis which may result in a multi organ failure. In addition to the standard of care, an immune-modulatory therapy tailored to each one of the different phenotypes should be used in order to prevent or reduce the release of cytokines responsible for organ damage and disease progression.

negative: Identification of Human Immune Cell Subtypes Most Vulnerable to IL-1β-induced Inflammatory Signaling Using Mass Cytometry IL-1β has emerged as a key mediator of the cytokine storm linked to high morbidity and mortality from COVID-19 and blockade of the IL-1 receptor (IL-1R) with Anakinra has entered clinical trials in COVID-19 subjects. Yet, knowledge of the specific immune cell subsets targeted by IL-1β and IL-1β-induced signaling pathways in humans is limited. Utilizing mass cytometry (CyTOF) of human peripheral blood mononuclear cells, we identified effector memory CD4 T cells and CD4−CD8low/-CD161+ T cells as the circulating immune subtypes with the greatest expression of p-NF-κB in response to IL-1β stimulation. Notably, CCR6 distinctly identified T cells most responsive to IL-1β. Other subsets including CD11c myeloid dendritic cells (mDCs), classical monocytes (CM), two subsets of natural killer cells (CD16−CD56brightCD161− and CD16−CD56dimCD161+) and a population of lineage−(Lin-) cells expressing CD161 and CD25 also showed IL-1β-induced expression of p-NF-kB. The IL-1R antagonist, Anakinra significantly inhibited IL-1β-induced p-NF-kB in the CCR6+ T cells and CD11c mDCs with a trending inhibition in CD14 monocytes and Lin−CD161+CD25+ cells. IL-1β also induced a rapid but much less robust increase in p-p38 expression as compared to p-NF-kB in the majority of these same immune cell subsets. Prolonged IL-1β stimulation greatly increased p-STAT3 and to a much lesser extent p-STAT1 and p-STAT5 in T cell subsets, monocytes, DCs and the Lin−CD161+CD25+ cells suggesting IL-1β-induced production of downstream STAT-activating cytokines, consistent with its role in cytokine storm. Interindividual heterogeneity and inhibition of this activation by Anakinra raises the intriguing possibility that assays to measure IL-1β-induced p-NF-kB in CCR6+ T cell subtypes could identify those at higher risk of cytokine storm and those most likely to benefit from Anakinra therapy.

negative: A systematic review of lopinavir therapy for SARS coronavirus and MERS coronavirus—A possible reference for coronavirus disease‐19 treatment option In the past few decades, coronaviruses have risen as a global threat to public health. Currently, the outbreak of coronavirus disease‐19 (COVID‐19) from Wuhan caused a worldwide panic. There are no specific antiviral therapies for COVID‐19. However, there are agents that were used during the severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) epidemics. We could learn from SARS and MERS. Lopinavir (LPV) is an effective agent that inhibits the protease activity of coronavirus. In this review, we discuss the literature on the efficacy of LPV in vitro and in vivo, especially in patients with SARS and MERS, so that we might clarify the potential for the use of LPV in patients with COVID‐19.

negative: T Cells in Viral Infections: The Myriad Flavours of Antiviral Immunity Viral diseases are a major cause of morbidity and mortality and result in a significant public health burden. T lymphocytes first identified in the chordate lineage and constitute a highly sophisticated branch of adaptive immune system. Apart from B cells, it is the only cell type that exhibits antigenic specificities; achieved by gene rearrangement. T cells are unique with respect to diversity of their subsets, which have distinct effector specificities, proliferative abilities, memory generation, and life span. T cells are impactful in viral infections by virtue of their capability to combat intracellular pathogens. The effector functions of T cells are mediated through cytokines/chemokines and by direct cytotoxicity of infected cells. T cell response can be beneficial or detrimental to host; prognosis depending on qualitative and quantitative differences in the response. Persistent viral infections are associated with functionally suboptimal, exhausted T cell responses, which are unable to clear virus. Specific subsets such as regulatory T cells (Tregs) dampen antiviral responses; thereby favouring viral persistence. However, Tregs protect the host from immunopathology by limiting perpetual inflammation. Certain other subsets such as Th17 cells may contribute to autoimmune component of viral infections. The importance of T cells is highlighted by the fact that modern vaccination and therapeutic approaches focus on modulating T cell frequencies and effector functions. This chapter emphasises the understanding how T cells influence outcomes of viral infections, modern vaccination and therapeutic strategies with thrust on T cell biology.

negative: Recomendaciones sobre el manejo clínico de la infección por el «nuevo coronavirus¼ SARS-CoV2. Grupo de trabajo de la Asociación Española de Pediatría (AEP)./ [Recommendations on the clinical management of the COVID-19 infection by the «new coronavirus¼ SARS-CoV2. Spanish Paediatric Association working group] On 31 December 2019, the Wuhan Municipal Committee of Health and Healthcare (Hubei Province, China) reported that there were 27 cases of pneumonia of unknown origin with symptoms starting on the 8 December. There were 7 serious cases with common exposure in market with shellfish, fish, and live animals, in the city of Wuhan. On 7 January 2020, the Chinese authorities identified that the agent causing the outbreak was a new type of virus of the Coronaviridae family, temporarily called «new coronavirus¼, 2019-nCoV. On January 30th, 2020, the World Health Organisation (WHO) declared the outbreak an International Emergency. On 11 February 2020 the WHO assigned it the name of SARS-CoV2 and COVID-19 (SARS-CoV2 and COVID-19). The Ministry of Health summoned the Specialties Societies to prepare a clinical protocol for the management of COVID-19. The Spanish Paediatric Association appointed a Working Group of the Societies of Paediatric Infectious Diseases and Paediatric Intensive Care to prepare the present recommendations with the evidence available at the time of preparing them.

negative: Vaccination with single plasmid DNA encoding IL-12 and antigens of severe fever with thrombocytopenia syndrome virus elicits complete protection in IFNAR knockout mice Severe fever with thrombocytopenia syndrome (SFTS) is an emerging tick-borne disease caused by SFTS virus (SFTSV) infection. Despite a gradual increase of SFTS cases and high mortality in endemic regions, no specific viral therapy nor vaccine is available. Here, we developed a single recombinant plasmid DNA encoding SFTSV genes, Gn and Gc together with NP-NS fusion antigen, as a vaccine candidate. The viral antigens were fused with Fms-like tyrosine kinase-3 ligand (Flt3L) and IL-12 gene was incorporated into the plasmid to enhance cell-mediated immunity. Vaccination with the DNA provides complete protection of IFNAR KO mice upon lethal SFTSV challenge, whereas immunization with a plasmid without IL-12 gene resulted in partial protection. Since we failed to detect antibodies against surface glycoproteins, Gn and Gc, in the immunized mice, antigen-specific cellular immunity, as confirmed by enhanced antigen-specific T cell responses, might play major role in protection. Finally, we evaluated the degree of protective immunity provided by protein immunization of the individual glycoprotein, Gn or Gc. Although both protein antigens induced a significant level of neutralizing activity against SFTSV, Gn vaccination resulted in relatively higher neutralizing activity and better protection than Gc vaccination. However, both antigens failed to provide complete protection. Given that DNA vaccines have failed to induce sufficient immunogenicity in human trials when compared to protein vaccines, optimal combinations of DNA and protein elements, proper selection of target antigens, and incorporation of efficient adjuvant, need to be further investigated for SFTSV vaccine development.

negative: The unleashing of the immune system in COVID-19 and sepsis: the calm before the storm? The novel coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is sorely testing health care systems and economies around the world and is rightly considered as the major health emergency in a century. Despite the course of the disease appearing to be mild in many cases, a significant proportion of symptomatic patients develop pneumonia requiring hospitalisation or progress to manifest respiratory complications leading to intensive care treatment. Potential interventions for SARS-CoV2-associated pneumonia are being tested, some of which holding promise, but as of today none of these has yet demonstrated outstanding efficacy in treating COVID-19. In this article, we discuss fresh perspectives and insights into the potential role of immune dysregulation in COVID-19 as well as similarities with systemic inflammatory response in sepsis and the rationale for exploring novel treatment options affecting host immune response.

negative: Infectious and Parasitic Diseases of the Alimentary Tract

negative: The time-series ages distribution of the reported COVID-2019 infected people suggests the undetected local spreading of COVID-2019 in Hubei and Guangdong provinces before 19th Jan 2020 COVID-2019 is broken out in China. It becomes a severe public health disaster in one month. Find the period in which the spreading of COVID-2019 was overlooked, and understand the epidemiological characteristics of COVID-2019 in the period will provide valuable information for the countries facing the threats of COVID-2019. The most extensive epidemiological analysis of COVID-2019 shows that older people have lower infection rates compared to middle-aged persons. Common sense is that older people prefer to report their illness and get treatment from the hospital compared to middle-aged persons. We propose a hypothesis that when the spreading of COVID-2019 was overlooked, we will find more older cases than the middle-aged cases. At first, we tested the hypothesis with 4597 COVID-2019 infected samples reported from 26th Nov 2019 to 17th Feb 2020 across the mainland of China. We found that 19th Jan 2020 is a critical time point. Few samples were reported before that day, and most of them were older ones. Then samples were explosively increased after that day, and many of them were middle-aged people. We have demonstrated the hypothesis to this step. Then, we grouped samples by their residences(provinces). We found that, in the provinces of Hubei and Guangdong, the ages of samples reported before 19th Jan 2020 are significantly higher than the ages of samples reported after that day. It suggests the COVID-2019 may be spreading in Hubei and Guangdong provinces before 19th Jan 2020 while people were unconscious of it. At last, we proposed that the ages distribution of each-day-reported samples could serve as a warning indicator of whether all potential COVID-2019 infected people are found. We think the power of our analysis is limit because 1. the work is data-driven, and 2. only ~5% of the COVID-2019 infected people in China are included in the study. However, we believe it still shows some value for its ability to estimate the possible unfound COVID-2019 infected people.

negative: Transmissible Gastroenteritis Virus Papain-Like Protease 1 Antagonizes Production of Interferon-β through Its Deubiquitinase Activity Coronaviruses (CoVs), such as human coronavirus NL63 (HCoV-NL63), severe acute respiratory syndrome CoV (SARS-CoV), murine hepatitis virus (MHV), porcine epidemic diarrhea virus (PEDV), and Middle East Respiratory Syndrome Coronavirus (MERS-CoV), encode papain-like (PL) proteases that inhibit Sendai virus- (SeV-) induced interferon (IFN-β) production. Recently, the crystal structure of transmissible gastroenteritis virus (TGEV) PL1 has been solved, which was similar to that of SARS-CoV PL2(pro), which may antagonize host innate immunity. However, very little is known about whether TGEV PL1 can antagonize host innate immune response. Here, we presented evidence that TGEV PL1 encoded by the replicase gene could suppress the IFN-β expression and inhibit the nuclear translocation of interferon regulatory factor 3 (IRF3). The ability to antagonize IFN-β production was dependent on the intact catalytic activity of PL1. Furthermore, TGEV PL1 exerted deubiquitinase (DUB) activity which strongly inhibited the retinoic acid-induced gene I- (RIG-1-) and stimulator of interferon gene- (STING-) dependent IFN expression. Our data collectively suggest that TGEV PL1 can inhibit the IFN-β expression and interfere with RIG-1- and STING-mediated signaling through a viral DUB activity. Our study has yielded strong evidence for the TGEV PL1 mechanisms that counteract the host innate immunity.

negative: Covid-19 and immunomodulation in IBD The current coronavirus pandemic is an ongoing global health crisis due to covid-19, caused by severe acute respiratory syndrome coronavirus 2. Although covid-19 leads to little or mild flu-like symptoms in the majority of affected patients, the disease may cause severe, frequently lethal complications such as progressive pneumonia, acute respiratory distress syndrome and organ failure driven by hyperinflammation and a cytokine storm syndrome. This situation causes various major challenges for gastroenterology. In the context of IBD, several key questions arise. For instance, it is an important question to understand whether patients with IBD (eg, due to intestinal ACE2 expression) might be particularly susceptible to covid-19 and the cytokine release syndrome associated with lung injury and fatal outcomes. Another highly relevant question is how to deal with immunosuppression and immunomodulation during the current pandemic in patients with IBD and whether immunosuppression affects the progress of covid-19. Here, the current understanding of the pathophysiology of covid-19 is reviewed with special reference to immune cell activation. Moreover, the potential implications of these new insights for immunomodulation and biological therapy in IBD are discussed.

negative: Immunology of COVID-19: current state of the science Abstract The coronavirus disease 2019 (COVID-19) pandemic, caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has affected millions of people worldwide, igniting an unprecedented effort from the scientific community to understand the biological underpinning of COVID19 pathophysiology. In this review, we summarize the current state of knowledge of innate and adaptive immune responses elicited by SARS-CoV-2 infection and the immunological pathways that likely contribute to disease severity and death. We also discuss the rationale and clinical outcome of current therapeutic strategies as well as prospective clinical trials to prevent or treat SARS-CoV-2 infection.

negative: Induced Pluripotent Stem Cells (iPSCs) Derived 3D Human Lung Organoids from Different Ethnicities to Understand the SARS-CoV2 Severity/Infectivity Percentage

negative: Clinical findings in a group of patients infected with the 2019 novel coronavirus (SARS-Cov-2) outside of Wuhan, China: retrospective case series OBJECTIVE: To study the clinical characteristics of patients in Zhejiang province, China, infected with the 2019 severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) responsible for coronavirus disease 2019 (covid-2019). DESIGN: Retrospective case series. SETTING: Seven hospitals in Zhejiang province, China. PARTICIPANTS: 62 patients admitted to hospital with laboratory confirmed SARS-Cov-2 infection. Data were collected from 10 January 2020 to 26 January 2020. MAIN OUTCOME MEASURES: Clinical data, collected using a standardised case report form, such as temperature, history of exposure, incubation period. If information was not clear, the working group in Hangzhou contacted the doctor responsible for treating the patient for clarification. RESULTS: Of the 62 patients studied (median age 41 years), only one was admitted to an intensive care unit, and no patients died during the study. According to research, none of the infected patients in Zhejiang province were ever exposed to the Huanan seafood market, the original source of the virus; all studied cases were infected by human to human transmission. The most common symptoms at onset of illness were fever in 48 (77%) patients, cough in 50 (81%), expectoration in 35 (56%), headache in 21 (34%), myalgia or fatigue in 32 (52%), diarrhoea in 3 (8%), and haemoptysis in 2 (3%). Only two patients (3%) developed shortness of breath on admission. The median time from exposure to onset of illness was 4 days (interquartile range 3-5 days), and from onset of symptoms to first hospital admission was 2 (1-4) days. CONCLUSION: As of early February 2020, compared with patients initially infected with SARS-Cov-2 in Wuhan, the symptoms of patients in Zhejiang province are relatively mild.

negative: Application and optimization of RT-PCR in diagnosis of SARS-CoV-2 infection Background: Coronavirus Disease 2019 (COVID-19) caused by Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a global threat to public health. Aiming to construct an efficient screening pattern, we comprehensively evaluated the performances of RT-PCR and chest CT in diagnosing COVID-19. Methods: The records including demographics, RT-PCR, and CT from 87 confirmed COVID-19 cases and 481 exclusion cases were collected. The diagnostic accuracy of the pharyngeal swab RT-PCR, CT, combination with the second pharyngeal swab RT-PCR or with CT were evaluated individually. Besides, all the stool RT-PCR results were plotted by time to explore the value of stool RT-PCR. Findings: Combination of RT-PCR and CT has the higher sensitivity (91.9%,79/86) than RT-PCR alone (78.2%，68/87) or CT alone (66.7%, 54 of 81) or combination of two RT-PCR tests (86.2%,75/87). There was good agreement between RT-PCR and CT (kappa-value, 0.430). In 34 COVID-19 cases with inconsistent results, 94.1% (n=32) are mild infection, 62.5% of which (20/32) showed positive RT-PCR. 46.7% (35/75) COVID-19 patients had at least one positive stool during the course. Two cases had positive stool earlier than the pharyngeal swabs. Importantly, one patient had consecutive positive stool but negative pharyngeal swabs. Interpretation: Combination of RT-PCR and CT with the highest sensitivity is an optimal pattern to screen COVID-19. RT-PCR is superior to CT in diagnosing mild infections. Stool RT-PCR should be considered as an item for improving discovery rate and hospital discharge. This study shed light for optimizing scheme of screening and monitoring of SARS-CoV-2 infection.

negative: Nelfinavir inhibits replication of severe acute respiratory syndrome coronavirus 2 in vitro In December 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in Wuhan, Hubei Province, China. No specific treatment has been established against coronavirus disease-2019 (COVID-19) so far. Therefore, it is urgently needed to identify effective antiviral agents for the treatment of this disease, and several approved drugs such as lopinavir have been evaluated. Here, we report that nelfinavir, an HIV-1 protease inhibitor, potently inhibits replication of SARS-CoV-2. The effective concentrations for 50% and 90% inhibition (EC50 and EC90) of nelfinavir were 1.13 µM and 1.76 µM respectively, the lowest of the nine HIV-1 protease inhibitors including lopinavir. The trough and peak serum concentrations of nelfinavir were three to six times higher than EC50 of this drug. These results suggest that nelfinavir is a potential candidate drug for the treatment of COVID-19 and should be assessed in patients with COVID-19.

negative: Anesthesia Management and Perioperative Infection Control in Patients With the Novel Coronavirus Anesthesiologists have a high risk of infection with COVID-19 during perioperative care and as first responders to airway emergencies. The potential of becoming infected can be reduced by a systematic and integrated approach that assesses infection risk. The latter leads to an acceptable choice of materials and techniques for personal protection and prevention of cross-contamination to other patients and staff. The authors have presented a protocolized approach that uses diagnostic criteria to clearly define benchmarks from the medical history along with clinical symptoms and laboratory tests. Patients can then be rapidly assigned into 1 of 3 risk categories that direct the choice of protective materials and/or techniques. Each hospital can adapt this approach to develop a system that fits its individual resources. Educating medical staff about the proper use of high-risk areas for containment serves to protect staff and patients.

negative: Lack of Antiviral Activity of Darunavir against SARS-CoV-2 Given the high need and the absence of specific antivirals for treatment of COVID-19 (the disease caused by severe acute respiratory syndrome-associated coronavirus-2 [SARS-CoV-2]), human immunodeficiency virus (HIV) protease inhibitors are being considered as therapeutic alternatives. Prezcobix/Rezolsta is a fixed-dose combination of 800 mg of the HIV protease inhibitor darunavir (DRV) and 150 mg cobicistat, a CYP3A4 inhibitor, which is indicated in combination with other antiretroviral agents for the treatment of HIV infection. There are currently no definitive data on the safety and efficacy of DRV/cobicistat for treatment of COVID-19. The in vitro antiviral activity of darunavir against a clinical isolate from a patient infected with SARS-CoV-2 was assessed. DRV showed no activity against SARS-CoV-2 at clinically relevant concentrations (EC50 >100 μM). Remdesivir, used as a positive control, showed potent antiviral activity (EC50 = 0.38 μM). Overall, the data do not support the use of DRV for treatment of COVID-19.

negative: English dictionaries, gold and silver standard corpora for biomedical natural language processing related to SARS-CoV-2 and COVID-19 Here we present a toolbox for natural language processing tasks related to SARS-CoV-2. It comprises English dictionaries of synonyms for SARS-CoV-2 and COVID-19, a silver standard corpus generated with the dictionaries and a gold standard corpus of 10 Pubmed abstracts manually annotated for disease, virus, symptom and protein/gene terms. This toolbox is freely available on github (on https://github.com/Aitslab/corona) and can be used for text analytics in a variety of settings related to the COVID-19 crisis. It will be expanded and applied in NLP tasks over the next weeks and the community is invited to contribute.

negative: Systemic Immunobiological, Immunosuppressant and Oncologic Agents for the Treatment of Dermatologic Diseases during the SARS‐Cov‐2 (COVID19) Pandemic Emergency: a Quick Review for a Quick Consultation The Precision Medicine Era has helped to better manage patients with immunological and oncological disease, improving the quality of life of this class of patients. Regarding the management of these patients and positivity to SARS‐Cov2, currently, limited data is available and information is evolving. In this quick review we have analyzed the mechanisms of action and related infective risk of drugs used for the treatment of immune‐mediated and oncologic skin conditions during the daily clinical practice. In general immunosuppressant and antineoplastic agents for dermatologic treatments do not require suspension and do not require special measures, if not those commonly observed. In the case of a COVID19 patient with complication (such as pneumonia, respiratory failure), treatment suspension should always be considered after taking into account the general condition of the patient, the risk‐benefit ratio and the pathophysiology of COVID19 infection. The COVID19 emergency pandemic does not imply an under‐treatment of existing skin conditions, which together with the SARS‐Cov2 infection may jeopardize the patient's life. This article is protected by copyright. All rights reserved.

negative: Coronavirus replication and pathogenesis: Implications for the recent outbreak of severe acute respiratory syndrome (SARS), and the challenge for vaccine development A novel coronavirus has been recently identified as the causative agent of the severe acute respiratory syndrome (SARS) outbreak that has accounted for more than 8000 infected people worldwide. This review will discuss current knowledge on coronavirus replication, pathogenesis, evolution, and vaccine strategies, as well as the most recent findings on SARS coronavirus.

negative: Parasites and their protection against COVID-19- Ecology or Immunology? Background: Despite the high infectivity of SARS-CoV-2, the incidence of COVID-19 in Africa has been slower than predicted. We aimed to investigate a possible association between parasitic infections and COVID-19. Methods: An ecological study in which we analysed WHO data on COVID-19 cases in comparison to WHO data on helminths and malaria cases using correlation, regression, and Geographical Information Services analyses. Results: Of the global 3.34 million COVID-19 cases and 238,628 deaths as at May 4th 2020, Africa reported 0.029/3.3 million (0.88%) cases and 1,064/238,628 (0.45%) deaths. In 2018, Africa reported 213/229 million (93%) of all malaria cases, 204/229 million (89%) of schistosomiasis cases, and 271/1068 million (25%) of soil-transmitted helminth cases globally. In contrast, Europe reported 1.5/3.3 million (45%) of global COVID-19 cases and 142,667/238,628 (59%) deaths. Europe had 5.8/1068 million (0.55%) soil-transmitted helminths cases and no malaria/schistosomiasis cases in 2018. We found an inverse correlation between the incidence of COVID-19 and malaria (r -0.17, p =0.002) and COVID-19 and soil-transmitted helminths (r -0.25, p <0.001). Malaria-endemic countries were less likely to have COVID-19 (OR 0.51, 95% CI 0.29-0.90; p =0.02). Similarly, countries endemic for soil-transmitted helminths were less likely to have COVID-19 (OR 0.24, 95% CI 0.13-0.44; p <0.001), as were countries endemic for schistosomiasis (OR 0.22, 95% CI 0.11-0.45; p<0.001). Conclusions: One plausible hypothesis for the comparatively low COVID-19 cases/deaths in parasite-endemic areas is immunomodulation induced by parasites. Studies to elucidate the relationship between parasitic infections and susceptibility to COVID-19 at an individual level are warranted.

negative: Prior immunization with severe acute respiratory syndrome (SARS)-associated coronavirus (SARS-CoV) nucleocapsid protein causes severe pneumonia in mice infected with SARS-CoV. The details of the mechanism by which severe acute respiratory syndrome-associated coronavirus (SARS-CoV) causes severe pneumonia are unclear. We investigated the immune responses and pathologies of SARS-CoV-infected BALB/c mice that were immunized intradermally with recombinant vaccinia virus (VV) that expressed either the SARS-CoV spike (S) protein (LC16m8rVV-S) or simultaneously all the structural proteins, including the nucleocapsid (N), membrane (M), envelope (E), and S proteins (LC16m8rVV-NMES) 7-8 wk before intranasal SARS-CoV infection. The LC16m8rVV-NMES-immunized group exhibited as severe pneumonia as the control groups, although LC16m8rVV-NMES significantly decreased the pulmonary SARS-CoV titer to the same extent as LC16m8rVV-S. To identify the cause of the exacerbated pneumonia, BALB/c mice were immunized with recombinant VV that expressed the individual structural proteins of SARS-CoV (LC16mOrVV-N, -M, -E, -S) with or without LC16mOrVV-S (i.e., LC16mOrVV-N, LC16mOrVV-M, LC16mOrVV-E, or LC16mOrVV-S alone or LC16mOrVV-N + LC16mOrVV-S, LC16mOrVV-M + LC16mOrVV-S, or LC16mOrVV-E + LC16mOrVV-S), and infected with SARS-CoV more than 4 wk later. Both LC16mOrVV-N-immunized mice and LC16mOrVV-N + LC16mOrVV-S-immunized mice exhibited severe pneumonia. Furthermore, LC16mOrVV-N-immunized mice upon infection exhibited significant up-regulation of both Th1 (IFN-gamma, IL-2) and Th2 (IL-4, IL-5) cytokines and down-regulation of anti-inflammatory cytokines (IL-10, TGF-beta), resulting in robust infiltration of neutrophils, eosinophils, and lymphocytes into the lung, as well as thickening of the alveolar epithelium. These results suggest that an excessive host immune response against the nucleocapsid protein of SARS-CoV is involved in severe pneumonia caused by SARS-CoV infection. These findings increase our understanding of the pathogenesis of SARS.

negative: Flexible endoscopic single-incision extraperitoneal implant and fixation of peritoneal dialysis catheter: proof of concept in the porcine model. BACKGROUND Peritoneal dialysis (PD) catheters placed in the pelvic space without anchoring present a high rate of migration. We aimed to assess the feasibility of a single-incision approach, using a flexible endoscopic preperitoneal tunneling for catheter implantation and fixation. MATERIALS AND METHODS Eight pigs were involved in this experimental study. A 2/0 Vicryl loop was sutured at the tip of a PD catheter. In 4 pigs, a 1.5 cm incision was made on the left paramedian line and the parietal peritoneal layer was identified by splitting rectal muscles. A gastroscope was inserted in the incision and advanced in the extraperitoneal space. An exit hole was made in the peritoneum over the low pelvic cavity. A guidewire was left in the abdominal cavity, and the PD catheter was inserted over the guidewire. The endoscope was inserted in the tunnel again, and endoscopic clips were deployed over the Vicryl loop to fix the catheter. In 4 pigs, the PD catheter was inserted laparoscopically using a two-port approach. The catheter's tip was fixed with laparoscopic clips on the Vicryl loop. A strain test to assess the force required to detach clips was performed using a digital dynamometer. RESULTS Operative time for flexible endoscopic tunneling was longer when compared to the laparoscopic implant (29.5 ± 4.43 vs. 22.7 ± 2.51 min). Mean force to displace the catheter was similar after flexible endoscopic fixation when compared to laparoscopic clip fixation (5.57 N ± 2.76 vs. 4.15 N ± 1.76). CONCLUSIONS Flexible endoscopic extraperitoneal tunneling allows for minimally invasive single-incision PD catheter placement and fixation.

negative: Recent progress and challenges in drug development against COVID-19 coronavirus (SARS-CoV-2) - an update on the status Abstract Coronaviruses are a large group of viruses known to cause illnesses that vary between the common cold and more severe diseases to include severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). A novel coronavirus was identified in December 2019 in Wuhan city, Hubei province, China. This virus represents a new strain that has not been previously identified in humans. The virus is now known as the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the resulting disease is called coronavirus disease 2019 (COVID-19). The World Health Organization (WHO) declared the novel coronavirus outbreak a global pandemic in March 2020. Despite rigorous global containment and quarantine efforts, the incidence of COVID-19 continues to rise, with more than 1,948,617 laboratory-confirmed cases and over 121,846 deaths worldwide. Currently, no specific medication is recommended to treat COVID-19 patients. However, governments and pharmaceutical companies are struggling to quickly find an effective drug to defeat the coronavirus. In the current review, we summarize the existing state of knowledge about COVID-19, available medications, and treatment options. Favilavir is an antiviral drug that is approved in Japan for common influenza treatment and is now approved to treat symptoms of COVID-19 in China. Moreover, Chloroquine and hydroxychloroquine, drugs used to treat malaria and arthritis, respectively, were recommended by the National Health Commission of the People's Republic of China for treatment of COVID-19. Presently, chloroquine and hydroxychloroquine are under investigation by the US Food and Drug Administration (FDA) as a treatment for COVID-19. The first COVID-19 vaccine is not expected to be ready for clinical trials before the end of the year.

negative: Practical experience on emergency ophthalmic surgery during the prevalence of COVID-19

negative: Renin-angiotensin-aldosterone system and COVID-19 infection Abstract With the multiplication of COVID-19 severe acute respiratory syndrome cases due to SARS COV2, some concerns about angiotensin-converting enzyme 1 (ACE1) inhibitors (ACEi) and angiotensin II type 1 receptor blockers (ARB) have emerged. Because the ACE2 (angiotensin-converting enzyme 2) enzyme is the receptor that allows SARS COV2 entry into cells, the fear was that pre-existing treatment with ACEi or ARB might increase the risk of developing severe or fatal severe acute respiratory syndrome in case of COVID-19 infection. The present article discusses these concerns. ACE2 is a membrane-bound enzyme (carboxypeptidase) that contributes to the inactivation of angiotensin II and therefore physiologically counters angiotensin II effects. ACEis do not inhibit ACE2. Although ARBs have been shown to upregulate ACE2 tissue expression in experimental animals, evidence was not always consistent in human studies. Moreover, to date there is no evidence that ACEi or ARB administration facilitates SARS COV2 cell entry by increasing ACE2 tissue expression in either animal or human studies. Finally, some studies support the hypothesis that elevated ACE2 membrane expression and tissue activity by administration of ARB and/or infusion of soluble ACE2 could confer protective properties against inflammatory tissue damage in COVID-19 infection. In summary, based on the currently available evidence and as advocated by many medical societies, ACEi or ARB should not be discontinued because of concerns with COVID-19 infection, except when the hemodynamic situation is precarious and case-by-case adjustment is required.

negative: The effect of immunosuppression on protective immunity of turkey poults against infection with turkey coronavirus Abstract The objective of the present study was to evaluate the protective effect of humoral and cellular immunities on turkeys infected with turkey coronavirus (TCV). Two trials were conducted with two separate hatches of turkey poults. Turkeys were experimentally immunosuppressed with cyclosporin A (CsA) or cyclophosphamide (CY) and infected with TCV. Prior to infection, treatment with CsA selectively suppressed T cell activity as revealed by 2–3 fold decreased (p<0.1) lymphocyte proliferation responses to a T cell mitogen, concanavalin A (Con A). Treatment with CY mainly induced B cell deficiency as indicated by significant reductions (p<0.05) in antibody responses to sheep erythrocytes 7 days after injection. Body weight gain of turkeys treated with CY was significantly lower (p<0.05) than that of untreated turkeys at 9 days post-infection (PI). Turkeys treated with CY had 1–2 fold higher immunofluorescent antibody assay (IFA) scores for TCV antigens (p<0.05) in the intestine than untreated turkeys at 9 or 14 days PI. These results suggested that humoral immunity against TCV infection may be important in turkeys.

negative: After 2015: infectious diseases in a new era of health and development Running over timescales that span decades or centuries, the epidemiological transition provides the central narrative of global health. In this transition, a reduction in mortality is followed by a reduction in fertility, creating larger, older populations in which the main causes of illness and death are no longer acute infections of children but chronic diseases of adults. Since the year 2000, the Millennium Development Goals (MDGs) have provided a framework for accelerating the decline of infectious diseases, backed by a massive injection of foreign investment to low-income countries. Despite the successes of the MDGs era, the inhabitants of low-income countries still suffer an enormous burden of disease owing to diarrhoea, pneumonia, HIV/AIDS, tuberculosis, malaria and other pathogens. Adding to the predictable burden of endemic disease, the threat of pandemics is ever-present and global. With a view to the future, this review spotlights five aspects of the fight against infection beyond 2015, when the MDGs will be replaced by a new set of goals for poverty reduction and sustainable development. These aspects are: exploiting the biological links between infectious and non-infectious diseases; controlling infections among the new urban majority; enhancing the response to international health threats; expanding childhood immunization programmes to prevent acute and chronic diseases in adults; and working towards universal health coverage. By scanning the wider horizon now, infectious disease specialists have the chance to shape the post-2015 era of health and development.

negative: COVID-19 control in China during mass population movements at New Year

negative: The Association between Obesity and Poor Outcome after COVID-19 Indicates a Potential Therapeutic Role for Montelukast It is widely believed that infection with the SARS-CoV2 virus triggers a disproportionate immune response which causes a devastating systemic injury, particularly in individuals with obesity, itself a chronic, multi-organ inflammatory disease. Immune cells accumulate in visceral adipose tissue and together with paracrine adipocytes release a wide range of biologically active cytokines (including IL-1β, IL5, IL6 and IL8) that can result in both local, pulmonary and systemic inflammation. A more intense ‘cytokine storm’ is postulated as the mechanism behind the extreme immune response seen in severe COVID-19. It is striking how dangerous the combination of obesity and COVID-19 is, resulting in a greater risk of ICU admission and a higher mortality. Furthermore, patients from a BAME background appear to have increased mortality after SARS-CoV2 infection; they also have a higher prevalence of central obesity and its metabolic complications. In the absence of an effective vaccine, the therapeutic potential of immune-modulating drugs is a priority, but the development of new drugs is expensive and time-consuming. A more pragmatic solution would be to seek to repurpose existing drugs, particularly those that might suppress the heightened cytokine activity seen in obesity, the major risk factor for a poor prognosis in COVID-19. Montelukast is a cysteinyl leukotriene receptor antagonist licensed to treat asthma and allergic rhinitis. It has been shown to diminish pulmonary response to antigen, tissue eosinophilia and IL-5 expression in inflammatory cells. It has also been shown to decrease elevated levels of IL-1β and IL8 in humans with viral upper respiratory tract infections compared with placebo-treated patients. In addition, in silico studies have demonstrated a high binding affinity of the montelukast molecule to the terminal site of the virus’s main protease enzyme which is needed for virus RNA synthesis and replication. Montelukast, which is cheap, safe and widely available would appear to have the potential to be an ideal candidate drug for clinical trials, particularly in early stage disease before irreparable tissue damage has already occurred. HYPOTHESIS: Through a direct anti-viral effect, or by suppression of heightened cytokine release in response to SARS-CoV2, montelukast will reduce the severity of immune-mediated multiorgan damage resulting from COVID-19, particularly in patients with central obesity and metabolic syndrome.

negative: Controlled, double-blind, randomized trial to assess the efficacy and safety of hydroxychloroquine chemoprophylaxis in SARS CoV2 infection in healthcare personnel in the hospital setting: A structured summary of a study protocol for a randomised controlled trial BACKGROUND: SARS-CoV-2 infection presents a high transmission in the group of health professionals in Spain (12-15% infected). Currently there is no accepted chemoprophylaxis but hydroxychloroquine (HDQ) is known to inhibit the coronavirus in vitro. Our hypothesis is that oral administration of hydroxychloroquine to healthcare professionals can reduce the incidence and prevalence of infection as well as its severity in this group. METHODS: Design: Prospective, single center, double blind, randomised, controlled trial (RCT). Participants: Adult health-care professionals (18-65 years) working in areas of high exposure and high risk of transmission of SARS-COV-2 (COVID areas, Intensive Care Unit –ICUs-, Emergency, Anesthesia and all those performing aerosol-generating procedures) will be included. Exclusion criteria include previous infection with SARS CoV2 (positive SARS-CoV-2 PCR or IgG serology), pregnancy or lactation, any contraindication to hydroxychloroquine or evidence of unstable or clinically significant systemic disease. INTERVENTIONS: Patients will be randomized (1:1) to receive once-daily oral Hydroxychloroquine 200mg for two months (HC group) or placebo (P group) in addition to the protective measures appropriate to the level of exposure established by the hospital. A serological evaluation will be carried out every 15 days with PCR in case of seroconversion, symptoms or risk exposure. Primary outcome is the percentage of subjects presenting infection (seroconversion and/or PCR +ve) by the SARS-Cov-2 virus during the observation period. Additionally, both the percentage of subjects in each group presenting Pneumonia with severity criteria (Curb 65 ≥2) and that of subjects requiring admission to ICU will be determined. DISCUSSION: While awaiting a vaccine, hygiene measures, social distancing and personal protective equipment are the only primary prophylaxis measures against SARS-CoV-2, but they have not been sufficient to protect our healthcare professionals. Some evidence of the in vitro efficacy of hydroxychloroquine against this virus is known, along with some clinical data that would support the study of this drug in the chemoprophylaxis of infection. However, there are still no data from controlled clinical trials in this regard. If our hypothesis is confirmed, hydroxychloroquine can help professionals fight this infection with more guarantees. PARTICIPANTS: This is a single-center study that will be carried out at the Marqués de Valdecilla University Hospital. 450 health professionals working at the Hospital Universitario Marqués de Valdecilla in areas of high exposure and high risk of transmission of SARS COV2 (COVID hospital areas, Intensive Care Unit, Emergency, Anesthesia and all those performing aerosol-generating procedures) will be included. Inclusion criteria: 1) Health professionals aged between 18 and 65 years (inclusive) at the time of the first screening visit; 2) They must provide signed written informed consent and agree to comply with the study protocol; 3) Active work in high exposure areas during the last two weeks and during the following weeks. Exclusion criteria: 1) Previous infection with SARS CoV2 (positive coronavirus PCR or positive serology with SARS Cov2 negative PCR and absence of symptoms); 2) Current treatment with hydroxychloroquine or chloroquine; 3) Hypersensitivity, allergy or any contraindication for taking hydroxychloroquine, in the technical sheet; 4) Previous or current treatment with tamoxifen or raloxifene; 5) Previous eye disease, especially maculopathy; 6) Known heart failure (Grade III to IV of the New York Heart Association classification) or prolonged QTc; 7) Any type of cancer (except basal cell) in the last 5 years; 6) Refusal to give informed consent; 8) Evidence of any other unstable or clinically significant untreated immune, endocrine, hematological, gastrointestinal, neurological, neoplastic or psychiatric illness; 9) Antibodies positive for the human immunodeficiency virus; 10) Significant kidney or liver disease; 11) Pregnancy or lactation. INTERVENTION AND COMPARATOR: 1. Intervention: (n = 225): One 200 mg hydroxychloroquine sulfate coated tablet once daily for two months. 2. Comparator (control group) (n = 225): One hydroxychloroquine placebo tablet (identical to that of the drug) once daily for two months. MAIN OUTCOMES: number and percentage of healthcare personnel presenting symptomatic and asymptomatic infection (see “Diagnosis of SARS CoV2 infection” below) by the SARS-Cov2 virus during the study observation period (8 weeks) in both treatment arms; number and percentage of healthcare personnel in each group presenting with Pneumonia with severity criteria (Curb 65 ≥2) and number and percentage of healthcare personnel requiring admission to the Intensive Care Unit (ICU) in both treatment arms. DIAGNOSIS OF SARS COV2 INFECTION: Determination of IgA, IgM and IgG type antibodies against SARS-CoV-2 using the Anti-SARS-CoV-2 ELISA kit (EUROIMMUN Medizinische Labordiagnostika AG, Germany) every two weeks. In cases of seroconversion, a SARS-CoV-2 PCR will be performed to rule out / confirm an active infection (RT-PCR in One Step: RT performed with mastermix (Takara) and IDT probes, following protocol published and validated by the CDC Evaluation of COVID-19 in case of SARS-CoV-2 infection RANDOMISATION: Participants will be allocated to intervention and comparator groups according to a balanced randomization scheme (1: 1). The assignment will be made through a computer-generated numeric sequence for all participants BLINDING (MASKING): Both participants and investigators responsible for recruiting and monitoring participants will be blind to the assigned arm. NUMBERS TO BE RANDOMISED (SAMPLE SIZE): Taking into account the current high prevalence of infection in healthcare personnel in Spain (up to 15%), to detect a difference equal to or greater than 8% in the percentage estimates through a two-tailed 95% CI, with a statistical power of 80% and a dropout rate of 5%, a total of 450 participants will need to be included (250 in each arm). TRIAL STATUS: The protocol approved by the health authorities in Spain (Spanish Agency for Medicines and Health Products “AEMPS”) and the Ethics and Research Committee of Cantabria (CEIm Cantabria) corresponds to version 1.1 of April 2, 2020. Currently, recruitment has not yet started, with the start scheduled for the second week of May 2020. TRIAL REGISTRATION: Eudra CT number: 2020-001704-42 (Registered on 29 March 2020) FULL PROTOCOL: The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol. The study protocol has been reported in accordance with the Standard Protocol Items: Recommendations for Clinical Interventional Trials (SPIRIT) guidelines (Additional file 2).

negative: The immune response to influenza in older humans: beyond immune senescence Despite widespread influenza vaccination programs, influenza remains a major cause of morbidity and mortality in older adults. Age-related changes in multiple aspects of the adaptive immune response to influenza have been well-documented including a decline in antibody responses to influenza vaccination and changes in the cell-mediated response associated with immune senescence. This review will focus on T cell responses to influenza and influenza vaccination in older adults, and how increasing frailty or coexistence of multiple (≥2) chronic conditions contributes to the loss of vaccine effectiveness for the prevention of hospitalization. Further, dysregulation of the production of pro- and anti-inflammatory mediators contributes to a decline in the generation of an effective CD8 T cell response needed to clear influenza virus from the lungs. Current influenza vaccines provide only a weak stimulus to this arm of the adaptive immune response and rely on re-stimulation of CD8 T cell memory related to prior exposure to influenza virus. Efforts to improve vaccine effectiveness in older adults will be fruitless until CD8 responses take center stage.

negative: Clinical Implications of SARS-Cov2 Interaction with Renin Angiotensin System Abstract SARS-CoV2 host cell infection is mediated by the binding to angiotensin-converting enzyme 2 (ACE2). Systemic dysregulation observed in SARS-CoV was previously postulated to be due to ACE2/Ang1-7/Mas axis downregulation, increased ACE2 activity was shown to mediate disease protection. Since angiotensin II receptor blockers (ARBs), ACE inhibitors, and mineralocorticoid receptor antagonists (MRAs) increase ACE2 receptor expression, it has been tacitly believed that the use of these agents may facilitate viral disease, thus they should not be used in high-risk patients with cardiovascular disease. Based on the anti-inflammatory benefits of the upregulation of the ACE2/Ang1-7/Mas axis and previously demonstrated benefits of lung function improvement in SARS-CoV infections, we hypothesize that the benefits of treatment with renin-angiotensin system inhibitors in SARS-COV2 may outweigh the risks and at the very least should not be withheld.

negative: A rate equation approach to model the denaturation or replication behavior of the SARS coronavirus As a newly emerging virus, little is known about the SARS coronavirus, whose outbreak has brought away several hundred people’s lives over the world in the year of 2003 and is seriously imperiling the human health. Revealing the denaturation and replication mechanisms of SARS coronavirus has great importance for successfully fighting SARS. However, experiments related to SARS coronavirus are extremely dangerous and therefore restricted only to certain specific labs with high safety standard. Clearly, predicting the behaviors of SARS coronavirus in a wide variety of environmental conditions, which are not easily accessible, are thus critically necessary. In this study, we proposed to quantify the survival time of SARS coronavirus either in vitro or in vivo, through introducing thermal rate process models established from the well-known Arrhenius law. The complex physical and chemical behaviors of the SARS coronavirus can then be attributed to its activation energy, frequency factor, damage function as well as the surrounding environmental conditions. Based on the first data on stability and resistance of SARS coronavirus measured by members of WHO laboratory network, the rate coefficients involved in the above equations were estimated for the first time. Predictions on the survival time of SARS coronavirus in different temperature scale were then performed. It was found theoretically that, such survival time falls in an extremely wide range, say from several seconds in high temperature to an almost infinitely long time in a low temperature environment, which has already or is being supported by the currently available tests data. Applications of the present theory to interpret several existing phenomena were presented and their implementations in developing new technical ways for SARS prevention and clinical therapy were discussed. Uncertainties involved in the theoretical models were also analyzed and predicted. Parametric studies were performed to test the effects of the rate coefficients to the survival time of SARS coronavirus. Some important factors, which can significantly vary the denaturation or replication process of SARS coronavirus were pointed out. Through regulating the parameters involved in the equation, certain potential therapies either through drug delivery or engineering approach to treat the SARS disease can possibly be established. Extension of the present model for further studies was also suggested. This study opens a new theoretical way for probing into the complex behaviors of SARS coronavirus. Modellierung der Denaturierung oder Repliziryng von SARS-Korona-Viren Zusammenfassung Der Kenntnisstand über die Eigenschaften des in 2003 neu aufgetretenen SARS Korona Virus, der einige Hundert Menschenleben gekostet hat, ist relativ gering. Die Ermittlung des Denaturierungs- und Replizierungsmechanismuses des SARS Virus ist für seine Bekämpfung von hoher Bedeutung. Experimentelle Untersuchungen an diesem extrem gefährlichen Virus dürfen nur durch Laboratorien mit einem hohen Sicherheitsstandard erfolgen. Die Vorhersage des Verhaltens des SARS Virus in unterschiedlichen Umgebungsbedingungen ist dabei erforderlich. In der vorliegenden Studie wird die überlebensdauer des Virus unter Labor- und realen Bedingungen durch Anwendung der bekannten Arrhenius-Beziehung für temperaturabhängige Vorgänge ermittelt. Das physikalische und chemische Verhalten des SARS Virus wird anhand der zugrundeliegenden Modell- Parameter beschrieben. Basierend auf den ersten Messungen von Mitgliedern des WHO-laboratory-network über die Stabilität und Widerstandsfähigkeit des Virus wurden erstmalig die Geschwindigkeitskoeffizienten des Berechnungsmodells bestimmt. Vorhersagen der Überlebensdauer des SARS-Virus unter unterschiedlichen Temperaturbedingungen wurden ausgeführt. Das sich hieraus ergebende, sehr unterschiedliche Ausmaß der Überlebensfähigkeit in Abhängigkeit der Umgebungstemperatur ist durch den Vergleich mit verfügbaren experimentellen Ergebnissen bestätigt worden. Die Anwendung der vorgestellten Modellierung zur Interpretation realer Phänomene und zur Entwicklung technischer Maßnahmen zur Vorbeugung und klinischen Therapierung von SARS wird diskutiert. Der Einfluß von Unsicherheiten des Modells wird analysiert und abgeschätzt. Parametrische Studien sind durchgeführt worden, um den Einfluß der Geschwindigkeitskoeffizienten auf die Überlebensdauer des SARS Virus darzustellen. Einige wichtige Einflußgrößen auf die Denaturierung und Replikationsfähigkeit des SARS Virus werden aufgezeigt. Durch eine Variation der Modellparameter kann die potentielle Wirksamkeit medikamentöser oder physikalischer Therapien abgeschätzt werden. Erweiterungsmöglichkeiten des vorgestellten Modells werden vorgeschlagen. Die vorliegende Studie ermöglicht neue, theoretische Vorgehensweisen zur Untersuchung des komplexen Verhaltensmusters des SARS Virus.

negative: MMDB: annotating protein sequences with Entrez's 3D-structure database Three-dimensional (3D) structure is now known for a large fraction of all protein families. Thus, it has become rather likely that one will find a homolog with known 3D structure when searching a sequence database with an arbitrary query sequence. Depending on the extent of similarity, such neighbor relationships may allow one to infer biological function and to identify functional sites such as binding motifs or catalytic centers. Entrez's 3D-structure database, the Molecular Modeling Database (MMDB), provides easy access to the richness of 3D structure data and its large potential for functional annotation. Entrez's search engine offers several tools to assist biologist users: (i) links between databases, such as between protein sequences and structures, (ii) pre-computed sequence and structure neighbors, (iii) visualization of structure and sequence/structure alignment. Here, we describe an annotation service that combines some of these tools automatically, Entrez's ‘Related Structure’ links. For all proteins in Entrez, similar sequences with known 3D structure are detected by BLAST and alignments are recorded. The ‘Related Structure’ service summarizes this information and presents 3D views mapping sequence residues onto all 3D structures available in MMDB ().

negative: Augmentation of immune responses to SARS coronavirus by a combination of DNA and whole killed virus vaccines We studied the immunogenicity of a DNA SARS-vaccine, a whole killed virus, or a whole killed and DNA vaccine combination. The DNA vaccine contained a plasmid encoding the SARS coronavirus (SARS-CoV) S protein under the control of the human CMV promoter and intron A. The whole killed virus vaccine was comprised of SARS-CoV, propagated in Vero-E6 cells, with subsequent β-propilactone inactivation and formulated with aluminum hydroxide adjuvant. Mice immunized twice with the DNA vaccine and once with the whole killed virus elicited higher antibody responses than mice immunized three times with the DNA vaccine or once with the whole killed virus vaccine. Mice immunized twice with the whole killed virus vaccine elicited higher antibody responses than mice immunized three times with the DNA vaccine or once with the whole killed virus vaccine. However, a combination of the vaccines induced T-helper type 1 (Th1) immune responses while the whole killed virus vaccine induced T helper type 2 (Th2) immune response. These results demonstrate that combination of the DNA vaccine and the whole killed virus vaccine can be used to enhance the magnitude and change the bias of the immune responses to SARS-CoV.

negative: Harnessing Cross-Reactive CD8(+) T(RM) Cells for Long-Standing Protection Against Influenza A Virus

negative: Coronavirus as silent killer: recent advancement to pathogenesis, therapeutic strategy and future perspectives The present outbreak associated with corona virus [CoVs] in China which is believed to be one of the massive eruptions towards mankind in 2019–2020. In the present scenario CoVs has been transmitted to the European and American regions through the travellers from wide spread countries like China and Japan. The viral disease is spreading through the contact in any form by the infected persons or patients and creating huge risk of mortality. CoVs are a single positive-sense RNA virus; mutation rates are higher than DNA viruses and indicate a more effective survival adaption mechanism. Human CoVs can cause common cold and influenza-like illness and a variety of severe acute respiratory disease such as pneumonia. Early in infection, CoVs infects epithelial cells, macrophages, T-cells, dendritic cells and also can affect the development and implantation of pro-inflammatory cytokines and chemokines. It mainly produces the melanoma differentiation associated with protein-5, retinoic acid inducible gene-1 and endosomal toll-like receptor 3. How CoVs affects the function of the immune system is still unclear due to lack of this knowledge. No Food and Drug Administration approved treatment is available till date. In this review, we are tried to explore the epidemiology, pathogenesis and current treatment of CoVs infection. The promising therapeutics molecules against CoVs and future prospective have been also discussed which will be helpful for researchers to find out the new molecules for the treatment of CoVs disease.

negative: Reactivity of antibodies in human serum with antigens of an enteropathogenic bovine coronavirus Antibodies in human serum against an enteropathogenic bovine coronavirus were detected by double immunodiffusion (DID), neutralization of infectivity, indirect immunofluorescence, and immune electron microscopy. Human sera reacting in the DID test neutralized the infectivity of the bovine coronaviruses to indices of 2.5 to > 5. Nineteen of 40 DID-negative, heat-inactivated sera had neutralizing indices of 1 to 3.0. Human serum with neutralizing and DID antibodies produced juxtanuclear and cytoplasmic fluorescence identical to that of bovine immune serum in cells infected with the bovine coronavirus. Antibodies in human and bovine sera interacted with the peplomeres of the bovine coronavirus, matting and bridging them, when present in excess, and facilitated formation of large viral aggregates when present in equivalent concentrations. Complement added to the virus-antibody complexes did not alter specifically the morphology of single, antibody-laden viral particles or viral particles in aggregates. Evidence of the transmission of coronavirus from experimentally inoculated calves to man, with ensuing gastroenteritis, was found by electron microscopic tracing of the coronavirus and its virus-antibody complexes.

negative: Protective humoral immunity in SARS-CoV-2 infected pediatric patients

negative: The COVID-19 pandemic: Important considerations for contact lens practitioners A novel coronavirus (CoV), the Severe Acute Respiratory Syndrome Coronavirus - 2 (SARS-CoV-2), results in the coronavirus disease 2019 (COVID-19). As information concerning the COVID-19 disease continues to evolve, patients look to their eye care practitioners for accurate eye health guidance. There is currently no evidence to suggest an increased risk of contracting COVID-19 through contact lens (CL) wear compared to spectacle lens wear and no scientific evidence that wearing standard prescription spectacles provides protection against COVID-19 or other viral transmissions. During the pandemic there will potentially be significant changes in access to local eyecare. Thus, it is imperative CL wearers are reminded of the steps they should follow to minimise their risk of complications, to reduce their need to leave isolation and seek care. Management of adverse events should be retained within optometric systems if possible, to minimise the impact on the wider healthcare service, which will be stretched. Optimal CL care behaviours should be the same as those under normal circumstances, which include appropriate hand washing (thoroughly with soap and water) and drying (with paper towels) before both CL application and removal. Daily CL cleaning and correct case care for reusable CL should be followed according to appropriate guidelines, and CL exposure to water must be avoided. Where the availability of local clinical care is restricted, practitioners should consider advising patients to reduce or eliminate sleeping in their CL (where patients have the appropriate knowledge about correct daily care and access to suitable lens-care products) or consider the option of moving patients to daily disposable lenses (where patients have appropriate lens supplies available). Patients should also avoid touching their face, including their eyes, nose and mouth, with unwashed hands and avoid CL wear altogether if unwell (particularly with any cold or flu-like symptoms).

negative: Animal-to-Human SARS-associated Coronavirus Transmission?

negative: Systematic Comparison of Two Animal-to-Human Transmitted Human Coronaviruses: SARS-CoV-2 and SARS-CoV After the outbreak of the severe acute respiratory syndrome (SARS) in the world in 2003, human coronaviruses (HCoVs) have been reported as pathogens that cause severe symptoms in respiratory tract infections. Recently, a new emerged HCoV isolated from the respiratory epithelium of unexplained pneumonia patients in the Wuhan seafood market caused a major disease outbreak and has been named the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This virus causes acute lung symptoms, leading to a condition that has been named as “coronavirus disease 2019” (COVID-19). The emergence of SARS-CoV-2 and of SARS-CoV caused widespread fear and concern and has threatened global health security. There are some similarities and differences in the epidemiology and clinical features between these two viruses and diseases that are caused by these viruses. The goal of this work is to systematically review and compare between SARS-CoV and SARS-CoV-2 in the context of their virus incubation, originations, diagnosis and treatment methods, genomic and proteomic sequences, and pathogenic mechanisms.

negative: Transcriptome analysis of PK-15 cells in innate immune response to porcine deltacoronavirus infection Porcine deltacoronavirus (PDCoV) is a newly emerged swine enteropathogenic coronavirus affecting pigs of all ages and causing diarrhea problems. Research findings indicate that PDCoV has evolved strategies to escape innate immune response in host cells, but mechanism of PDCoV in innate immune modulation is not well understood. In this study, we report our findings on identifying the alterations of host cell innate immune response affected by PDCoV infection and exploring the gene expression profiles of PK-15 cells at 0, 24, and 36 h PDCoV post infection by RNA sequencing. A total of 3,762 and 560 differentially expressed genes (DEGs) were screened by comparison of uninfected PK-15 cells and infected PK-15 cells at 24 h post infection (hpi) (INF_24h versus NC), and also comparison of infected PK-15 cells between 24 and 36 hpi (INF_36h versus INF_24h), which included 156 and 23 porcine innate immune-related genes in the DEGs of INF_24h versus NC and INF_36h versus INF_24h, respectively. Gene Ontology function classification and Kyoto Encyclopedia of Genes and Genomes signaling pathway enrichment analysis were performed based on the DEGs that exhibited the same expression tendencies with most of the innate immune-associated genes among these PK-15 cell samples described above. The enrichment results indicated that extensive gene functions and signaling pathways including innate immune-associated functions and pathways were affected by PDCoV infection. Particularly, 4 of 5 innate immune signaling pathways, which were primarily affected by PDCoV, played important roles in I-IFN’s antiviral function in innate immune response. Additionally, 16 of the host cell endogenous miRNAs were predicted as potential contributors to the modulation of innate immune response affected by PDCoV. Our research findings indicated that the innate immune-associated genes and signaling pathways in PK-15 cells could be modified by the infection of PDCoV, which provides a fundamental foundation for further studies to better understand the mechanism of PDCoV infections, so as to effectively control and prevent PDCoV-induced swine diarrheal disease outbreaks.

negative: The COVID-19 pandemic from an ophthalmologist’s perspective Abstract The current COVID-19 pandemic is rapidly spreading around the world. The first doctor to report this new disease was an ophthalmologist: this exemplifies the role of ophthalmologists in an infectious disease pandemic. Here we review how SARS-Cov2 affects the eye and discuss implications for ophthalmologists.

negative: Probiotics and COVID-19: is there any link? Understanding mechanisms of the novel SARS-CoV2 infection and progression, can provide potential novel targets for prevention and/or treatment. This could be achieved via the inhibition of viral entry and/or replication, or by suppression the immunologic response that is provoked by the infection (known as the cytokine storm). Probiotics are defined as "live microorganisms that, when administered in adequate amounts, confer a health benefit on the host". There is scarcity of evidence about the relationship between COVID-19 and gut microbiota. So, whether or not these supplements can prevent or ameliorate COVID-19 associated symptoms is not fully understood. The aim of this paper is to provide an indirect evidence about the utility of probiotics in combating COVID-19 or its associated symptoms, through the review of its antiviral and anti-inflammatory properties in vitro, animal models, and human trials.

negative: Association of past dengue fever epidemics with the risk of Zika microcephaly at the population level in Brazil Despite all the research done on the first Zika virus (ZIKV) epidemics, it was only after the Brazilian epidemic that the Congenital Zika Syndrome was described. This was made possible due to the large number of babies born with microcephaly in the Northeast region (NE) in a narrow time. We hypothesize that the fivefold difference in the rate of microcephalic neonates between the NE and other regions is partially an effect of the population prior immunity against Dengue viruses (DENV), that cross-react with ZIKV. In this ecological study, we analysed the interaction between dengue fever epidemics from 2001 to 2014 and the 2015/2016 microcephaly epidemic in 400 microregions in Brazil using random-effects models under a Bayesian approach. The estimated effect of the time lag between the most recent large dengue epidemic (>400/100,000 inhabitants) and the microcephaly epidemic ranged from protection (up to 6 years prior) to an increased risk (from 7 to 12 years). This sustained window of protection, larger than described in previous longitudinal studies, is possibly an effect of herd immunity and of multiple exposures to DENV that could boost immunity.

negative: No evidence of SARS-CoV-2 in semen of males recovering from COVID-19 Abstract Objective To describe detection of SARS-CoV-2 in seminal fluid of patients recovering from COVID-19 and describe the expression profile of ACE2 and TMPRSS2 within the testicle. Design observational, cross-sectional study Setting Tertiary referral center Patients Thirty-four adult Chinese males diagnosed with COVID-19 through confirmatory quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) from pharyngeal swab samples Intervention None Main Outcome Measures Identification of SARS-CoV-2 on qRT-PCR of single ejaculated semen samples. Semen quality was not assessed. Expression patterns of ACE2 and TMPRSS2 in the human testis are explored through previously published single-cell transcriptome datasets. Results Six patients (19%) demonstrated scrotal discomfort concerning for viral orchitis around the time of COVID-19 confirmation. SARS-CoV-2 was not detected in semen after a median of 31 days (IQR: 29-36 days) from COVID-19 diagnosis. Single-cell transcriptome analysis demonstrates sparse expression of ACE2 and TMPRSS2, with almost no overlapping gene expression. Conclusions SARS-CoV-2 was not detected in the semen of patients recovering from COVID-19 one month after COVID-19 diagnosis. ACE2-mediated viral entry of SARS-CoV-2 into target host cells is unlikely to occur within the human testicle based on ACE2 and TMPRSS2 expression. The long-term effects of SARS-CoV-2 on male reproductive function remain unknown.

negative: Identification of an infectious bronchitis coronavirus strain exhibiting a classical genotype but altered antigenicity, pathogenicity, and innate immunity profile Avian coronavirus infectious bronchitis virus (IBV) poses economic threat to the poultry industry worldwide. Pathogenic IBV 3575/08 was isolated from broilers vaccinated with the attenuated viral vaccine derived from a Taiwan strain 2575/98. In this study, extensive investigations were conducted on the genome sequences, antigenicity, pathogenicity, and host immune responses of several IBV strains in specific-pathogen-free chickens. Sequence analyses revealed that 3575/08 and 2575/98 shared high homology in their structural genes, but not in non-structural accessory proteins such as 3a, 3b and 5b. Despite a high degree of homology in their spike protein genes, cross neutralization test showed low cross protection between 3575/08 and 2575/98, suggesting distinct antigenicity for the two strains. Animal challenge experiments exhibited strong respiratory and renal pathogenicity for 3575/08. In addition, early and prolonged viral shedding and rapid viral dissemination were observed. Immune gene expression profiling by PCR array showed chickens infected with 3575/08 had delayed expression of a subset of early innate immune genes, whereas chickens infected with the wild-type or attenuated-type 2575/08 revealed quick gene induction and efficient virus control. In summary, this study reveals a new IBV strain, which harbors a known local genotype but displays remarkably altered antigenicity, pathogenicity and host defenses.

negative: From SARS to MERS, Thrusting Coronaviruses into the Spotlight Coronaviruses (CoVs) have formerly been regarded as relatively harmless respiratory pathogens to humans. However, two outbreaks of severe respiratory tract infection, caused by the severe acute respiratory syndrome coronavirus (SARS-CoV) and the Middle East respiratory syndrome coronavirus (MERS-CoV), as a result of zoonotic CoVs crossing the species barrier, caused high pathogenicity and mortality rates in human populations. This brought CoVs global attention and highlighted the importance of controlling infectious pathogens at international borders. In this review, we focus on our current understanding of the epidemiology, pathogenesis, prevention, and treatment of SARS-CoV and MERS-CoV, as well as provides details on the pivotal structure and function of the spike proteins (S proteins) on the surface of each of these viruses. For building up more suitable animal models, we compare the current animal models recapitulating pathogenesis and summarize the potential role of host receptors contributing to diverse host affinity in various species. We outline the research still needed to fully elucidate the pathogenic mechanism of these viruses, to construct reproducible animal models, and ultimately develop countermeasures to conquer not only SARS-CoV and MERS-CoV, but also these emerging coronaviral diseases.

negative: Dicistroviruses The Dicistroviridae are a family of small icosahedral viruses with single-stranded RNA, positive-sense genomes that infect invertebrates. The genomes are organized with their nonstructural proteins encoded at the 5′ end with the structural proteins at the 3′ end. Characteristically, the two open reading frames are separated by an untranslated region that is capable of acting as an internal ribosome entry site (IRES). In addition to the structural proteins being expressed from this IRES, translation usually initiates from a noncanonical amino acid, generally alanine. The dicistroviruses share a number of characteristics, for example, virion structure, genomic organization, and the absence of subgenomic RNAs with other picorna-like viruses of plants, animals, and protists that suggest a shared evolutionary origin and a higher-order taxonomic grouping for such viruses. Most dicistroviruses, with the exception of cricket paralysis virus (CrPV), have restricted host ranges and only infect species from a single insect order. In contrast, CrPV is able to infect over 20 species of insects and several insect cell lines. Most dicistroviruses have vertical and horizontal components in their transmission and generally produce few noticeable disease symptoms. Infection with dicistroviruses does, however, usually result in a shortened life span and reduced fecundity of the host.

negative: Bakterielle oder virale Atemwegsentzündung? Neuer Bedside-Test hilft weiter Bei Verdacht auf akute Atemwegsinfektion kann ein Bedside-Test, der auf 20 gängige Lungenpathogene testet und Ergebnisse in einer Stunde liefert, unnötige Krankenhaus- und Antibiotika-Behandlungen verhindern.

negative: Antibody-based therapies for COVID-19: Can Europe move faster? Michel Goldman and colleagues call on the European medical and scientific community to coordinate efforts on immunotherapy-based approaches to coronavirus.

negative: Toxicant-Induced Hepatic Injury The sudden failure of a previously healthy and functioning liver is a dramatic and devastating event. Acute liver failure is the common final pathway of a multitude of conditions and insults, all of which result in massive hepatic necrosis or loss of normal hepatic function. The ensuing multiorgan system failure frequently has a fatal outcome, with mortality rates in most series ranging from approximately 55% to 95% [1]. Acute liver failure (ALF, previously often referred to as fulminant hepatic failure (FHF)) knows no age boundaries, with many cases occurring in those younger than 30 years. Short of excellent intensive care unit (ICU) support and liver transplantation in selected cases, few viable treatment options are available. Over the past few decades, however, survival has been improved by anticipation, recognition, and early treatment of associated complications, as well as the application of prognostic criteria for early identification of patients requiring liver transplantation (along with improvement in the techniques and science of transplantation itself). The etiology of ALF varies from country to country and the incidence change over time. Paracetamol (acetaminophen) has now replaced viral hepatitis as the leading cause of ALF [2]. In a study from London including 310 patients with ALF in the period 1994–2004, 42% of the cases were caused by paracetamol [3], whereas this was only the cause in 2% of 267 patients in Spain from 1992 to 2000 [4]. However, less than 10% of all liver transplants are performed in patients with ALF [5, 6].

negative: Traditional Chinese medicine for COVID-19 treatment

negative: New Respiratory Viruses and the Elderly The diagnostics of respiratory viral infections has improved markedly during the last 15 years with the development of PCR techniques. Since 1997, several new respiratory viruses and their subgroups have been discovered: influenza A viruses H5N1 and H1N1, human metapneumovirus, coronaviruses SARS, NL63 and HKU1, human bocavirus, human rhinoviruses C and D and potential respiratory pathogens, the KI and WU polyomaviruses and the torque teno virus. The detection of previously known viruses has also improved. Currently, a viral cause of respiratory illness is almost exclusively identifiable in children, but in the elderly, the detection rates of a viral etiology are below 40%, and this holds also true for exacerbations of chronic respiratory illnesses. The new viruses cause respiratory symptoms like the common cold, cough, bronchitis, bronchiolitis, exacerbations of asthma and chronic obstructive pulmonary disease and pneumonia. Acute respiratory failure may occur. These viruses are distributed throughout the globe and affect people of all ages. Data regarding these viruses and the elderly are scarce. This review introduces these new viruses and reviews their clinical significance, especially with regard to the elderly population.

negative: The case for Chronotherapy in COVID‐19 induced Acute Respiratory Distress Syndrome (ARDS). COVID‐19, the disease resulting from infection by a novel coronavirus: SARS‐Cov2 that has rapidly spread since November 2019 leading to a global pandemic. SARS‐Cov2 has infected over 4 million people and caused over 290,000 deaths worldwide. Although most cases are mild, a subset of patients develop a severe and atypical presentation of Acute Respiratory Distress Syndrome (ARDS) that is characterised by a cytokine release storm (CRS). Paradoxically, treatment with anti‐inflammatory agents and immune regulators has been associated with worsening of ARDS. We hypothesize that the intrinsic circadian clock of the lung and the immune system may regulate individual components of CRS and thus chronotherapy may be used to effectively manage ARDS in COVID‐19 patients.

negative: Interferon response in murine plasmacytoid dendritic cells after SARS coronavirus infection

negative: Novel coronavirus disease (COVID-19) in children Coronavirus disease (COVID-19) was firstly reported at the end of 2019. The disease rapidly spread all around the world in a few months and was declared a worldwide pandemic by WHO in March 2020. By April 9, there were 1,436,198 confirmed COVID-19 cases in the world, nearly with 6% mortality rate. This novel infectious disease causes respiratory tract illness that may generally occur as mild upper respiratory tract disease or pneumonia. In older patients and/or patients with underlying conditions, it may result in acute respiratory distress syndrome, multi organ failure and even death. According to the current literature, children account approximately for 1%–5% of diagnosed COVID-19 cases. Generally, COVID-19 seems to be a less severe disease for children than adults. Approximately 90% of pediatric patients are diagnosed as asymptomatic, mild, or moderate disease. However, up to 6.7% of cases may be severe. Severe illness is generally seen in patients smaller than 1 year of age and patients who have underlying disesases. The epidemiological and clinical patterns of COVID-19 and treatment approaches in pediatric patients still remain unclear although many pediatric reports are published. This review aims to summarize the current epidemics, clinical presentations, diagnosis, and treatment of COVID-19 in pediatric patients.

negative: Cross-Protection against H5N1 Influenza Virus Infection Is Afforded by Intranasal Inoculation with Seasonal Trivalent Inactivated Influenza Vaccine Background. Avian H5N1 influenza A virus is an emerging pathogen with the potential to cause substantial human morbidity and mortality. We evaluated the ability of currently licensed seasonal influenza vaccine to confer cross-protection against highly pathogenic H5N1 influenza virus in mice. Methods. BALB/c mice were inoculated 3 times, either intranasally or subcutaneously, with the trivalent inactivated influenza vaccine licensed in Japan for the 2005–2006 season. The vaccine included A/NewCaledonia/20/99 (H1N1), A/NewYork/55/2004 (H3N2), and B/Shanghai/361/2002 viral strains and was administered together with poly(I):poly(C(12)U) (Ampligen) as an adjuvant. At 14 days after the final inoculation, the inoculated mice were challenged with either the A/HongKong/483/97, the A/Vietnam/1194/04, or the A/Indonesia/6/05 strain of H5N1 influenza virus. Results. Compared with noninoculated mice, those inoculated intranasally manifested cross-reactivity of mucosal IgA and serum IgG with H5N1 virus, as well as both a reduced H5N1 virus titer in nasal-wash samples and increased survival, after challenge with H5N1 virus. Subcutaneous inoculation did not induce a cross-reactive IgA response and did not afford protection against H5N1 viral infection. Conclusions. Intranasal inoculation with annual influenza vaccine plus the Toll-like receptor—3 agonist, poly(I): poly(C(12)U), may overcome the problem of a limited supply of H5N1 virus vaccine by providing cross-protective mucosal immunity against H5N1 viruses with pandemic potential.

negative: Vaccination for seasonal influenza in patients with cancer: recommendations of the Italian Society of Medical Oncology (AIOM) BACKGROUND: Influenza virus causes annual epidemics in the winter–spring season with significant morbidity in the general population and important mortality in high-risk groups, including cancer patients. Opinions on the suitability of patients with malignancies not undergoing active treatment and in different phases of antineoplastic therapy, to receive influenza vaccination, vary considerably among oncologists, sometimes even within one center. METHODS: We reviewed available data, including recommendations by national health authorities, on impact of influenza in patients with cancer and their capacity to mount protective immunological responses to vaccination, thus allowing, on behalf of Italian Association of Medical Oncology, to make suitable recommendations for the prevention and treatment of seasonal influenza. RESULTS AND DISCUSSION: Patients with cancer often have disease- or treatment-related immunosuppression, and as a consequence, they may have a suboptimal serologic response to influenza vaccination. The protective effect of the different preparations of influenza vaccines in patients with cancer has not been widely investigated, especially in adult patients harboring solid tumors. The optimal timing for administration of influenza vaccines in patients receiving chemotherapy is also not clearly defined. However, since vaccination is the most effective method, along with antiviral drugs in selected patients, for preventing influenza infection, it has to be recommended for cancer patients. Implementing vaccination of close contacts of oncology patients would be an additional tool for enhancing protection in fragile patient populations.

negative: The old but new: Can unfractioned heparin and low molecular weight heparins inhibit proteolytic activation and cellular internalization of SARS-CoV2 by inhibition of host cell proteases? Currently, our world is facing the 2019 Novel Coronavirus (COVID-19) outbreak and tremendous efforts are made for developing drugs to treat and vaccines to prevent the disease. At present, there is no specific antiviral drug or vaccine for COVID-19. The pathogenic infectivity of the virus requires the S1 subunit of the spike (S) protein to bind the host cell receptor, angiontensin converting enzyme (ACE2). While the binding to host cell receptor is the first step of infection, the entrance of the virus into the cell needs the cleavage of S1–S2 subunits to expose S2 for fusion to cell membrane via host proteases including cathepsins, cell surface transmembrane protease/serine (TMPRSS) proteases, furin, trypsin and factor Xa. Previous in vitro studies have shown that factor Xa inhibition can decrease viral infectivity. We suppose that host cell proteases including furin (as expressed highly in lungs), factor Xa and cathepsin are possible targets to decrease viral burden, therefore unfractioned heparin and low molecular weight heparin-LMWH (specifically dalteparin and tinzaparin for their anti inflammatory action) can be potential inhibitors of multiple endoproteases involved in virus infectivity. Our hypothesis needs to be tested in in vitro and clinical studies, however as we are in an urgent situation as the burden of SARS-CoV2 is increasing all around the world, we recommend the usage of unfractioned heparin or LMWH in intensive care unit (ICU) and non-ICU hospitalized patients with the risk–benefit judgement of the clinician. Whether our hypothesis is clinically applicable and successful in decreasing viral infection will be evaluated for further studies.

negative: Antiviral B cell and T cell immunity in the lungs Respiratory viruses are frequent causes of repeated common colds, bronchitis and pneumonia, which often occur unpredictably as epidemics and pandemics. Despite those decimating effects on health and decades of intensive research, treatments remain largely supportive. The only commonly available vaccines are against influenza virus, and even these need improvement. The lung shares some features with other mucosal sites, but preservation of its especially delicate anatomical structures necessitates a fine balance of pro- and anti-inflammatory responses; well-timed, appropriately placed and tightly regulated T cell and B cell responses are essential for protection from infection and limitation of symptoms, whereas poorly regulated inflammation contributes to tissue damage and disease. Recent advances in understanding adaptive immunity should facilitate vaccine development and reduce the global effect of respiratory viruses.

negative: Current studies of convalescent plasma therapy for COVID-19 may underestimate risk of antibody-dependent enhancement

negative: Relevance of SARS-CoV-2 in food safety and food hygiene: potential preventive measures, suggestions and nanotechnological approaches Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is easily transmitted from person to person, which has fueled the ongoing pandemic. Governments in different countries have taken drastic actions such as complete lockdown. However, little attention has been paid to food safety and its potential linkage with the coronavirus disease (COVID-19) pandemic. SARS-CoV-2 spread from staff to food products or food surfaces is conceivable. At least, instead of consuming unpackaged or uncovered foods, consumption of boiled or canned foods processed at high temperatures should be preferred. Before consumption, consumers should clean the surface of canned foods. In addition to recommending or enforcing simple precautions, such as using masks, governments must conduct mandatory SARS-CoV-2 tests regularly and intermittently for personnel who handle food materials or supporting materials (e.g., plastic pouches). Local markets, such as those in Wuhan, which sell live animals and exotic foods for consumption, are a concern. Trade of exotic or wild animals, unhygienic marketplace conditions, and not cooking at high temperatures ought to be prohibited. The consumption of vitamins, minerals, and other food-derived compounds such as omega fatty acids is a prudent way to improve the performance of the immune system. In addition, nano-encapsulated materials with controlled release properties may be useful in protecting food products and packaging from SARS-CoV-2 contamination.

negative: Novel coronavirus (COVID-19) infection: What a doctor on the frontline needs to know Coronavirus disease 2019 (COVID-19) is a zoonotic respiratory infection originating from Wuhan, China. Rapidly spreading from Wuhan to all inhabited continents of the world, the World Health Organisation declared COVID-19 a pandemic on March 11, 2019. Infected patients present with fever and cough; radiological features include bilateral infiltrates on chest x-ray and computed tomography scanning. Management is supportive with oxygen supplementation, broad-spectrum antibiotics as well as careful fluid balancing. A number of drugs, both new and old, are currently in clinical trials and being used on an experimental basis in clinical practice. The COVID-19 pandemic is the greatest worldwide public health crisis of a generation, and has led to seismic political, economic and social changes. This review provides an overview of COVID-19 for junior doctors who find themselves on a new frontline of healthcare.

negative: Feasibility Study of Mitigation and Suppression Intervention Strategies for Controlling COVID-19 Outbreaks in London and Wuhan Recent outbreaks of coronavirus disease 2019 (COVID-19) has led a global pandemic cross the world. Most countries took two main interventions: suppression like immediate lockdown cities at epicentre or mitigation that slows down but not stopping epidemic for reducing peak healthcare demand. Both strategies have their apparent merits and limitations; it becomes extremely hard to conduct one intervention as the most feasible way to all countries. Targeting at this problem, this paper conducted a feasibility study by defining a mathematical model named SEMCR that can access effectiveness of mitigation, suppression and hybrid interventions for controlling COVID-19 outbreaks in London and Wuhan. It extended traditional SEIR (Susceptible-Exposed Infectious-Recovered) model by adding two key features: a direct connection between Exposed and Recovered populations, and separating infections into mild and critical cases. It defined parameters to classify two stages of COVID-19 control: active contain by isolation of cases and contacts, passive contain by suppression or mitigation. The model was fitted and evaluated with public dataset containing daily number of confirmed active cases including Wuhan and London during January, 2020 and March 2020. The simulated results showed that 1) Immediate suppression taken in Wuhan significantly reduced the total exposed and infectious populations to 119610, but it has to be consistently maintained at least 90 days (by the middle of April 2020). Its success heavily relied on sufficiently external support from other places of China. This mode were not suitable to other countries that have no sufficient health resources. 2) In London, it is possible to take a hybrid intervention of suppression and mitigation for every 2 or 3 weeks over a longer period to balance the total infections and economic loss. While the total infectious populations in this scenario would be possibly 2 times than the one taking suppression, economic loss and recovery of London would be less affected. 3) Both in Wuhan and London cases, one important issue of fitting practical data was that there were a large portion (probably 62.9% in Wuhan) of self-recovered populations that were asymptomatic or mild symptomatic. These people might think they have been healthy at home and did not go to hospital for COVID-19 tests. Early release of intervention intensity potentially increased a risk of the second outbreak. One limitation of our model was that our prediction of infections and deaths depended on a parameter estimation of intervention intensity that presented by average number contacts with susceptible individuals as infectious individuals in a certain region. It assumed that each intervention had equivalent effects on the reproduction number R in different regions over time. Practical effectiveness of implementing intervention intensity might be varied with respect to cultures or other issues of certain county.

negative: BCG as a game-changer to prevent the infection and severity of COVID-19 pandemic Abstract The impact of COVID-19 is changing country wise and depends on universal immunization policies. COVID-19 badly affects countries that did not have universal immunization policies or having them only for the selective population of countries (highly prominent population) like Italy, USA, UK, Netherland, etc. Universal immunization of BCG can provide great protection against the COVID-19 infection because the BCG vaccine gives broad protection against respiratory infections. BCG vaccine induces expressions of the gene that are involved in the antiviral innate immune response against viral infections with long-term maintenance of BCG vaccine-induced cellular immunity. COVID-19 cases are reported very much less in the countries with universal BCG vaccination policies such as India, Afghanistan, Nepal, Bhutan, Bangladesh, Israel, Japan, etc. as compared to without BCG implemented countries such as the USA, Italy, Spain, Canada, UK, etc. BCG vaccine provides protection for 50 to 60 years of immunization, so the elderly population needs to be revaccinated with BCG. Several countries started clinical trials of the BCG vaccine for health care workers and elderly people. BCG can be uses as a prophylactic treatment until the availability of the COVID-19 vaccine.

negative: Coevolution spreading in complex networks The propagations of diseases, behaviors and information in real systems are rarely independent of each other, but they are coevolving with strong interactions. To uncover the dynamical mechanisms, the evolving spatiotemporal patterns and critical phenomena of networked coevolution spreading are extremely important, which provide theoretical foundations for us to control epidemic spreading, predict collective behaviors in social systems, and so on. The coevolution spreading dynamics in complex networks has thus attracted much attention in many disciplines. In this review, we introduce recent progress in the study of coevolution spreading dynamics, emphasizing the contributions from the perspectives of statistical mechanics and network science. The theoretical methods, critical phenomena, phase transitions, interacting mechanisms, and effects of network topology for four representative types of coevolution spreading mechanisms, including the coevolution of biological contagions, social contagions, epidemic–awareness, and epidemic–resources, are presented in detail, and the challenges in this field as well as open issues for future studies are also discussed.

negative: Severe Immune Thrombocytopenia Complicated by Intracerebral Haemorrhage Associated with Coronavirus Infection: A Case Report and Literature Review Immune thrombocytopenic purpura (ITP) is an autoimmune disorder that causes isolated thrombocytopenia. Many viruses have been identified as triggering the autoimmune process, including HIV, MCV, EBV, parvovirus, rubella and measles. However, ITP in association with coronavirus infection has not previously been reported. We describe the case of a healthy man who presented with severe ITP complicated by intracranial haemorrhage following upper respiratory tract infection. An infection screen revealed coronavirus infection. LEARNING POINTS: Coronavirus can cause severe immune thrombocytopenic purpura (ITP). Intracerebral haemorrhage is an uncommon presentation of ITP. Intravenous immunoglobulin and steroids are very effective treatments for severe ITP.

negative: Longitudinal study of Middle East Respiratory Syndrome coronavirus infection in dromedary camel herds in Saudi Arabia, 2014–2015 Two herds of dromedary camels were longitudinally sampled with nasal and rectal swabs and serum, between September 2014 and May 2015, and the samples were tested for Middle East Respiratory Syndrome (MERS) coronavirus RNA and antibodies. Evidence of MERS-CoV infection was confirmed in one herd on the basis of detection of virus RNA in nasal swabs from three camels and significant increases in the antibody titers from three others. The three viruses were genetically identical, thus indicating introduction of a single virus into this herd. There was evidence of reinfection of camels that were previously seropositive, thus suggesting that prior infection does not provide complete immunity from reinfection, a finding that is relevant to camel vaccination strategies as a means to prevent zoonotic transmission.

negative: A tug-of-war between severe acute respiratory syndrome coronavirus 2 and host antiviral defence: lessons from other pathogenic viruses World Health Organization has declared the ongoing outbreak of coronavirus disease 2019 (COVID-19) a Public Health Emergency of International Concern. The virus was named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by the International Committee on Taxonomy of Viruses. Human infection with SARS-CoV-2 leads to a wide range of clinical manifestations ranging from asymptomatic, mild, moderate to severe. The severe cases present with pneumonia, which can progress to acute respiratory distress syndrome. The outbreak provides an opportunity for real-time tracking of an animal coronavirus that has just crossed species barrier to infect humans. The outcome of SARS-CoV-2 infection is largely determined by virus-host interaction. Here, we review the discovery, zoonotic origin, animal hosts, transmissibility and pathogenicity of SARS-CoV-2 in relation to its interplay with host antiviral defense. A comparison with SARS-CoV, Middle East respiratory syndrome coronavirus, community-acquired human coronaviruses and other pathogenic viruses including human immunodeficiency viruses is made. We summarize current understanding of the induction of a proinflammatory cytokine storm by other highly pathogenic human coronaviruses, their adaptation to humans and their usurpation of the cell death programmes. Important questions concerning the interaction between SARS-CoV-2 and host antiviral defence, including asymptomatic and presymptomatic virus shedding, are also discussed.

negative: The double burden of diabetes and global infection in low and middle-income countries Four out of five people in the world with diabetes now live in low- and middle-income countries (LMIC), and the incidence of diabetes is accelerating in poorer communities. Diabetes increases susceptibility to infection and worsens outcomes for some of the world’s major infectious diseases such as tuberculosis, melioidosis and dengue, but the relationship between diabetes and many neglected tropical diseases is yet to be accurately characterised. There is some evidence that chronic viral infections such as hepatitis B and HIV may predispose to the development of type 2 diabetes by chronic inflammatory and immunometabolic mechanisms. Helminth infections such as schistosomiasis may be protective against the development of diabetes, and this finding opens up new territory for discovery of novel therapeutics for the prevention and treatment of diabetes. A greater understanding of the impact of diabetes on risks and outcomes for infections causing significant diseases in LMIC is essential in order to develop vaccines and therapies for the growing number of people with diabetes at risk of infection, and to prioritise research agendas, public health interventions and policy. This review seeks to give an overview of the current international diabetes burden, the evidence for interactions between diabetes and infection, immune mechanisms for the interaction, and potential interventions to tackle the dual burden of diabetes and infection.

negative: COVID-19 and pets: When pandemic meets panic Abstract As the novel coronavirus outbreak spreads globally with devastating effects on human health, pets are also becoming unnecessary victims amidst the pandemic panic. Many have been reluctantly left home alone by owners who have been forced to temporarily evacuate their homes. And, although no evidence exists to indicate that they can either transmit the virus or develop its associated coronavirus disease 2019 (COVID-19), fear among the public that pets might play a role in spreading COVID-19 has resulted in pets being abandoned or even killed. This article outlines some of the ways in which the current pandemic has negatively impacted the welfare of pets. It also highlights the relationships between animal, human, and environmental health, as well as the importance of taking a collaborative transdisciplinary One Health approach to help prevent future COVID-19 outbreaks.

negative: Coronavirus JHM-Induced Demyelinating Encephalomyelitis in Rats: Influence of Immunity on the Course of Disease Publisher Summary Disease processes of the central nervous system (CNS) accompanied by demyelination may be the result of a viral infection or the consequence of an immunopathological reaction directed against myelin. In acute viral infections, the infection of oligodendroglial cells, leading to cell destruction, may be the main mechanism for inducing this neuropathological lesion. In the case of a persistent virus infection in oligodendroglia cells, however, it is conceivable that functional impairment of oligodendroglia cells, or the induction of an immune reaction to the agent that may cross-react with brain antigens, could eventually cause demyelination. Therefore, pathogenic studies on subacute or chronic demyelinating encephalomyelitides in association with viral infections may provide information on the mechanisms involved in demyelination. In rats, depending on the biological property of the virus material used, the genetic background and immune response of the host, a subacute or late demyelinating encephalomyelitis can be induced, accompanied by primary demyelination. This provides a model for analysis of the virus and host factors interacting in the pathogenesis of these diseases.

negative: Precaution of 2019 novel coronavirus infection in department of oral and maxillofacial surgery Abstract The epidemic of the 2019 novel coronavirus (2019-nCoV) infection has presented as a critical period. Until February 23th 2020, more than 77 000 cases of 2019-nCoV infection have been confirmed in China, which has a great impact on economy and society. It has also interferred with ordinary medical practice of oral and maxillofacial surgery seriously. In order to protect oral and maxillofacial surgery medical staff from 2019-nCoV infection during the outbreak period, this paper suggests the necessary medical protective measures for oral and maxillofacial surgery outpatient and ward.

negative: Cross-protective immune responses elicited by a Korean variant of infectious bronchitis virus. Infectious bronchitis virus (IBV) infections cause great economic losses to the poultry industry worldwide. IBVs continuously evolve by developing mutations in antigenic sites; therefore, an IBV vaccine that provides broad cross-protection can be a highly relevant and practical method in IBV control strategies. Although some IBV vaccine strains are known to provide protection against multiple IBV serotypes, in general commercially available IBV vaccine strains provide protection against antigenically related viruses but not distinct heterologous viruses. In the present study we characterized the Korean variant IBV K40/09 strain with regard to its immunogenicity and protective efficacy against seven currently circulating IBV serotypes. Three-week-old specific-pathogen-free chickens were intraocularly immunized with the IBV K40/09 strain at 10(3.5) 50% egg infective dose (EID50). Three weeks after immunization all the birds were challenged with seven different strains at 10(4.5) EID50. Chickens immunized with the IBV K40/09 strain showed significantly high levels of protection against all challenge viruses at the trachea and kidney levels. Our results suggest that IBV K40/09 could be useful to ensure IBV vaccine effectiveness owing to its cross-protective ability. Therefore, the IBV K40/09 strain merits consideration as a vaccine candidate to prevent infection as well as the spread of new IBV strains and many IBV variants that have been reported worldwide.

negative: Ebola Policies That Hinder Epidemic Response by Limiting Scientific Discourse There is an unprecedented epidemic of Ebola virus disease (EVD) in west Africa. There has been a strong response from dedicated health professionals. However, there have also been irrational and fear-based responses that have contributed to misallocation of resources, stigma, and deincentivizing volunteers to combat Ebola at its source. Recently, the State of Louisiana Department of Health and Hospitals issued a ban on those coming from affected countries wishing to attend the annual meetings of American Society of Tropical Medicine and Hygiene and the American Public Health Association, both of which were held in New Orleans. We argue against such policies, question evidence and motivations, and discuss their practical and ethical implications in hampering effective responses to EVD by the scientific community. We aim to shed light on this issue and its implications for the future of public health interventions, reflect on the responsibility of health providers and professional societies as advocates for patients and the public health, and call for health professionals and societies to work to challenge inappropriate political responses to public health crises.

negative: Molecular targets for the rational design of drugs to inhibit SARS coronavirus Despite years of research, the precise determinants of coronavirus replication and pathogenesis remain unidentified. What is known of the pathogenesis of the severe acute respiratory syndrome coronavirus (SARS-CoV) is limited, but clinical observations suggest that both viral-induced cytotoxicity and host immune-mediated destruction contribute to the severity of disease. This summary discusses recent advances in coronavirus research that will facilitate the identification of crucial molecular targets for the rational design of SARS therapeutics. Section Editor: Anne Moscona – Department of Pediatrics, Mount Sinai School of Medicine, One Gustave L. Levy Place, Box 1198, New York, NY 10029, USA When the SARS coronavirus came dramatically to attention as a fatal and potentially pandemic respiratory disease, the scientific response was swift and effective. The etiological agent was identified, the genome was cloned and sequenced, and large strides have been made in understanding key points in the viral life cycle, including recent identification of a functional host cell receptor and solution of the three-dimensional structure of the viral attachment protein. Much of this progress was possible only because a foundation of basic coronavirus biology existed. The Denison laboratory has been at the forefront of the small group of investigators who have dissected the basic features of coronaviruses. Denison has discovered critical mechanisms in the life cycle of the coronaviruses and is a key figure in the effective and urgent application of this knowledge to SARS.

negative: Aluminum Nanoparticles Acting as a Pulmonary Vaccine Adjuvant-Delivery System (VADS) Able to Safely Elicit Robust Systemic and Mucosal Immunity ABSTRACT: Vulnerability of respiratory mucosa to invasions of airborne pathogens, such as SARS-CoV, MERS-CoV and avian viruses which sometimes cause a life-threatening epidemic and even pandemic, underscores significance of developing a pulmonary vaccine adjuvant-delivery system (VADS). Herein, 30-nm aluminum nanoparticles (ANs), unlike the mostly used adjuvant alum which is unsuitable for delivering pulmonary vaccines due to side effects, proved able to act as a VADS fitting inhalation immunization to elicit wide-spread anti-antigen immunity. In vitro ANs facilitated cellular uptake of their cargos and, after pulmonary vaccination, induced mouse production of high levels of anti-antigen IgG in serum and IgA in saliva, nasal, bronchoalveolar and also vaginal fluids. Besides, IFN-γ and anti-antigen IgG2a enriched in immunized mice which meanwhile showed no obvious lung inflammation indicated balanced Th1/Th2 responses were safely induced. These outcomes suggest ANs may be an efficient pulmonary VADS for defending against pathogens, especially, the ones invading hosts via respiratory system. GRAPHIC ABSTRACT: Aluminum nanoparticles can safely induce humoral and cellular immunity at systemic and mucosal level through pulmonary vaccination to contrast the conventional adjuvant alum. [Image: see text]

negative: The landscape of lung bronchoalveolar immune cells in COVID-19 revealed by single-cell RNA sequencing The novel coronavirus SARS-CoV-2, etiological agent of recently named Coronavirus infected disease (COVID-19) by WHO, has caused more than 2, 000 deaths worldwide since its emergency in Wuhan City, Hubei province, China, in December, 2019. The symptoms of COVID-19 varied from modest, mild to acute respiratory distress syndrome (ARDS), and the latter of which is generally associated with deregulated immune cytokine production; however, we currently know little as to the interplay between the extent of clinical symptoms and the compositions of lung immune microenvironment. Here, we comprehensively characterized the lung immune microenvironment with the bronchoalveolar lavage fluid (BALF) from 3 severe and 3 mild COVID-19 patients and 8 previously reported healthy lung controls through single-cell RNA sequence (scRNA-seq) combined with TCR-seq. Our data shows that monocyte-derived FCN1+ macrophages, whereas notFABP4+ alveolar macrophages that represent a predominant macrophage subset in BALF from patients with mild diseases, overwhelm in the severely damaged lungs from patients with ARDS. These cells are highly inflammatory and enormous chemokine producers implicated in cytokine storm. Furthermore, the formation of tissue resident, highly expanded clonal CD8+ T cells in the lung microenvironment of mild symptom patients suggests a robust adaptive immune response connected to a better control of COVID-19. This study first reported the cellular atlas of lung bronchoalveolar immune microenvironment in COVID-19 patients at the single-cell resolution, and unveiled the potential immune mechanisms underlying disease progression and protection in COVID-19.

negative: Chapter 15 Innate Humoral Defense Factors Abstract Although innate immunity came into the research spotlight in the late 1990s when its instructive role in the adaptive immune response was recognized, innate humoral defense factors have a much older history. The exocrine secretions of the body contain a plethora of distinct soluble factors (lysozyme, lactoferrin, peroxidases, proline-rich proteins, histatins, etc.) that protect the body from mucosal microbial pathogens. More recent studies have established that the humoral arm of innate immunity contains a heterogeneous group of pattern-recognition molecules (e.g., pentraxins, collectins, and ficolins), which perform diverse host-defense functions, such as agglutination and neutralization, opsonization, control of inflammation, and complement activation and regulation. These pattern-recognition molecules, which act as functional predecessors of antibodies (“ante-antibodies”), and the classic soluble innate defense factors form an integrated system with complementary specificity, action, and tissue distribution, and they are the subject of this chapter.

negative: The Potential Role of Th17 Immune Responses in Coronavirus Immunopathology and Vaccine-induced Immune Enhancement Abstract Increasing evidence points to host Th17 inflammatory responses as contributing to the severe lung pathology and mortality of lower respiratory tract infections from coronaviruses. This includes host inflammatory and cytokine responses to COVID-19 caused by the SARS-2 coronavirus (SARS CoV2). From studies conducted in laboratory animals, there are additional concerns about immune enhancement and the role of potential host immunopathology resulting from experimental human COVID-19 vaccines. Here we summarize evidence suggesting there may be partial overlap between the underlying immunopathologic processes linked to both coronavirus infection and vaccination, and a role for Th17 in immune enhancement and eosinophilic pulmonary immunopathology. Such findings help explain the link between viral-vectored coronavirus vaccines and immune enhancement and its reduction through alum adjuvants. Additional research may also clarify links between COVID-19 pulmonary immunopathology and heart disease.

negative: Low-income countries are more immune to COVID-19: A misconception OBJECTIVE: The COVID-19 pandemic has hit countries such as Italy, Spain, France, UK, and the USA with great force, whereas the number of cases in countries such as India and most parts of Africa is comparatively lower. Such observation has made many people believe that the low-income countries may be more immune to COVID-19. Theories such as warm climate, weaker strain of the virus, and cross-protection by malaria have been popularly put forward. One such interesting theory is that since the general people of the low- income countries are mostly habituated to dwell in lesser hygienic condition and with lesser medical attention throughout their lifetime; hence, they have naturally acquired better immunity and more resilience against many infective diseases. MATERIALS AND METHODS: We sought to investigate the above claim by comparing the case fatality rate (CFR) as well as number of cases per million population versus the gross domestic product at purchasing power parity per capita of different countries. RESULTS: We found that while the number of cases showed a slight decline in the lower-income countries, the CFR was independent of the financial condition of the country. CONCLUSION: We conclude that the theory of better immunity in economically poor countries is a misconception. We suggest that people must come out of these misconceptions and resort to strict home isolation.

negative: Discovering drugs to treat coronavirus disease 2019 (COVID-19). The SARS-CoV-2 virus emerged in December 2019 and then spread rapidly worldwide, particularly to China, Japan, and South Korea. Scientists are endeavoring to find antivirals specific to the virus. Several drugs such as chloroquine, arbidol, remdesivir, and favipiravir are currently undergoing clinical studies to test their efficacy and safety in the treatment of coronavirus disease 2019 (COVID-19) in China; some promising results have been achieved thus far. This article summarizes agents with potential efficacy against SARS-CoV-2.

negative: Achievements and highlights for Infection, Disease and Health

negative: Chapter 3 Biological HRPs in wastewater Abstract Biological high-risk pollutants (HRPs) have become a serious threat to human health worldwide, and wastewater is one of the major sources of them in a natural environment. Despite the long history of wastewater research, comprehensive understanding of the role and behavior of HRPs during wastewater treatment is still limited owing to the complexity of the community. In recent decades, the rapid development of molecular tools, especially the wide application of next generation sequencing technologies, helps to unravel the community composition, structure, and dynamic variation in wastewater. Overall, this chapter mainly focuses on biological HRPs, including bacteria, viruses, protozoa, helminth, biotoxins, antibiotic resistance genes and antibiotic resistant bacteria in wastewater. The characteristics, classification, fates, functions, and health implications of these HRPs are introduced in detail. Moreover, the biogeography of HRPs is a research hotspot in recent years, and available information is also summarized in this chapter. Finally, we also propose the future research needs of HRPs in wastewater after the comprehensive summary of the existing research reports. This chapter is wished to be helpful for beginners to quickly understand the biological HRPs in wastewater.

negative: The impact of community psychological responses on outbreak control for severe acute respiratory syndrome in Hong Kong. OBJECTIVE To examine the public's knowledge and perception of SARS and the extent to which various precautionary measures have been adopted. DESIGN Cross sectional survey. SETTING General population of Hong Kong at the height of the SARS outbreak (29 March to 6 April 2003). PARTICIPANTS 1115 ethnic Chinese adults. MAIN RESULTS Forty per cent did not recognise fomites as a possible mode of transmission whereas 55.1% believed that the infection could be transmitted airborne. A large proportion (30.1%) believed they were very or somewhat likely to contract SARS while only one quarter believed they were very likely to survive if they contracted the disease, benchmarked against an actual case fatality ratio of 2.8% at the time of the survey and 15%-20% according to current best estimates. Precautionary measures directed against person to person droplet spread were generally adopted by most while the prevention of transmission through fomites was not practised as frequently. Respondents with higher risk perceptions and a moderate level of anxiety were most likely to take comprehensive precautionary measures against the infection, as were older, female, more educated people as well as those with a positive contact history and SARS-like symptoms. CONCLUSIONS The findings demonstrate that the promotion of protective personal health practices to interrupt the self sustaining transmission of the SARS virus in the community must take into account background perceptions of risk and anxiety levels of the public at large. Continuing public education about preventive measures should be targeted at the identified groups with low current uptake of precautions.

negative: Coronavirus 2019-nCoV: A brief perspective from the front line Abstract A novel coronavirus, designated as 2019-nCoV, hit the central Chinese city of Wuhan in late December 2019, and subsequently spread rapidly to all provinces of China and multiple countries. As of 0:00 am February 9, 2020, a total of 37,287 cases have been confirmed infection of 2019-nCoV in China mainland, and 302 cases have also been cumulatively reported from 24 countries. According to the latest data, a total of 813 deaths occurred in China mainland, with the mortality reaching approximately 2.2%. At present, there is no vaccine or specific drugs for the human coronavirus. Therefore, it is critical to understand the nature of the virus and its clinical characteristics, in order to respond to the 2019-nCoV outbreak. Thus, the present study briefly but comprehensively summarizes the not much but timely reports on the 2019-nCoV.

negative: Prolonged SARS‐CoV‐2 RNA shedding: Not a rare phenomenon A few studies have reported the long shedding of SARS-CoV-2 RNA. However, the duration of RNA shedding in Wuhan is rarely known and the meaning of the prolonged shedding is still under investigation. Almost 10% patients diagnosed of COVID-19 had a RNA shedding longer than 30 days even if the symptom elimination. The IgM was in a high level in the 9th week after symptom onset in these prolonged-RNA-shedding patients. Further study should be conducted to know the infectivity of the virus and the relationship between RNA shedding and antibody expression. This article is protected by copyright. All rights reserved.

negative: Fighting COVID-19 The current COVID-19 pandemic caused by the novel coronavirus (SARS-CoV2) poses a threat to global health owing to its high rate of spread and severe forms of respiratory infection. The lack of vaccines and antivirals prevents clinical strategies against the disease, creating an emerging need for the development of safe and effective treatments. Strategies for vaccine development include complete vaccines against viruses, subunits, and nucleic acids, but are still in their early stages. Studies carried out to date on possible SARS-CoV2 drug targets highlight glycoprotein S, Mpro (main protease or protease type 3C), and a member of the transmembrane serine protease II families (TMPRSS2). However, due to the pandemic state, priority is given to marketed drugs. These include chloroquine (CQ), hydroxychloroquine (HCQ), nitazoxanide, remdesivir, Lopinavir/ritonavir (LPV / r), in addition to treatment with convalescent plasma. But, therapeutic specific effects against SARS-CoV2 have not yet been verified. Most of the information obtained about treatment is based on preliminary and limited studies. We conclude that, at this time of emergency, the search for new therapies is more urgent due to the need to save lives. Thus, we point out as interesting targets for future more specific research: glycoprotein S, Mpro, and TMPRSS2.

negative: Crossing barriers: infections of the lung and the gut Although known as respiratory pathogens, severe acute respiratory syndrome (SARS) and its sister coronaviruses frequently cause enteric symptoms. In addition, other classically non-enteric viruses (such as HIV and influenza) may also have enteric effects that are crucial in their pathogeneses. These effects can be due to direct infection of the gut mucosa, but can also be because of decreased antibacterial defenses, increased mucosal permeability, bacterial translocation, and systemic leak of endotoxin. SUPPLEMENTARY INFORMATION: The online version of this article (doi:10.1038/mi.2008.79) contains supplementary material, which is available to authorized users.

negative: Therapeutic ISCOMATRIX™ adjuvant vaccine elicits effective anti-tumor immunity in the TRAMP-C1 mouse model of prostate cancer Cancer vaccine development has proven challenging with the exception of some virally induced cancers for which prophylactic vaccines exist. Currently, there is only one FDA approved vaccine for the treatment of prostate cancer and as such prostate cancer continues to present a significant unmet medical need. In this study, we examine the effectiveness of a therapeutic cancer vaccine that combines the ISCOMATRIX™ adjuvant (ISCOMATRIX) with the Toll-like receptor 3 agonist, polyinosinic–polycytidylic acid (Poly I:C), and Flt3L, FMS-like tyrosine kinase 3 ligand. We employed the TRAMP-C1 (transgenic adenocarcinoma of the mouse prostate) model of prostate cancer and the self-protein mPAP (prostatic acid phosphatase) as the tumor antigen. ISCOMATRIX™–mPAP–Poly I:C–Flt3L was delivered in a therapeutic prime-boost regime that was consistently able to achieve complete tumor regression in 60% of animals treated and these tumor-free animals were protected upon rechallenge. Investigations into the underlying immunological mechanisms contributing to the effectiveness of this vaccine identified that both innate and adaptive responses are elicited and required. NK cells, CD4(+) T cells and interferon-γ were all found to be critical for tumor control while tumor infiltrating CD8(+) T cells became disabled by an immunosuppressive microenvironment. There is potential for broader application of this cancer vaccine, as we have been able to demonstrate effectiveness in two additional cancer models; melanoma (B16-OVA) and a model of B cell lymphoma (Eµ-myc-GFP-OVA). ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s00262-020-02597-6) contains supplementary material, which is available to authorized users.

negative: Immunogenicity of a malaria parasite antigen displayed by Lactococcus lactis in oral immunisations A putative protective protein from Plasmodium falciparum merozoites, MSA2, was expressed in two different ways on the cell surface of the Gram-positive food-grade bacterium, Lactococcus lactis. The first display format exploits an LPXTG-type anchoring motif of the lactococcal proteinase PrtP to covalently anchor MSA2 to the genetically modified producer cells. In a second display format, MSA2 was fused to the peptidoglycan-binding domain (Protein Anchor) of the lactococcal cell wall hydrolase AcmA and was non-covalently rebound to the surface of non-genetically modified, non-living high-binder L. lactis cells, termed Gram-positive enhancer matrix (GEM) particles. The L. lactis recombinants carrying covalently bound MSA2 were used to immunise rabbits through nasal and oral routes. The highest levels of IgG antibodies reacting with near-native MSA2 on merozoites was elicited by oral administration. Intestinal antibodies to MSA2 were produced only after oral immunisation. MSA2-specific T(h)-cell activation could be demonstrated. Based on these results, the immunogenicity in oral immunisations of MSA2, bound non-covalently to non-genetically modified L. lactis GEM particles, was compared with MSA2 that was bound covalently to genetically modified L. lactis. These two forms elicited similar titres of serum antibodies. The results illustrate the potential of using non-genetically modified L. lactis as a safe vaccine delivery vehicle to elicit systemic antibodies, thereby avoiding the dissemination of recombinant DNA into the environment.

negative: Outbreak of Novel Coronavirus (SARS-CoV-2): First Evidences From International Scientific Literature and Pending Questions On 31 December, 2019, a cluster of 27 pneumonia cases of unknown etiology was reported by Chinese health authorities in Wuhan City (China) [ ]

negative: Animal coronavirus vaccines: lessons for SARS. Severe acute respiratory syndrome (SARS) emerged in China and spread globally as a human pandemic. It is caused by a new coronavirus (CoV) of suspect animal origin. The emergence of SARS stunned medical scientists, but veterinary virologists had previously recognized CoVs as causing fatal respiratory or enteric disease in animals with interspecies transmission and wildlife reservoirs. Because of its public health impact, major efforts are focused on development of SARS vaccines. Occurrence of CoV disease at mucosal surfaces necessitates the stimulation of local immunity, having an impact on the vaccine type, delivery and adjuvant needed to achieve mucosal immunity. Such immunity is often short-lived, requires frequent boosting and may not prevent re-infection, all factors complicating CoV vaccine design. SARS vaccine efforts should be enhanced by understanding the correlates of protection and reasons for the success or failure of animal CoV vaccines. This review will focus on studies of immunity and protection in swine to the enteric CoV, transmissible gastroenteritis (TGEV) versus the respiratory variant, porcine respiratory CoV (PRCV), comparing live, inactivated and subunit vaccines, various vaccine vectors, routes and adjuvants. In addition avian infectious bronchitis CoV (IBV) vaccines targeted for protection of the upper respiratory tract of chickens are discussed. Unfortunately, despite long-term efforts, effective vaccines to prevent enteric CoV infections remain elusive, and generally live, but not killed vaccines, have induced the most consistent protection against animal CoVs. Confirmation of the pathogenesis of SARS in humans or animals models that mimic SARS may further aid in vaccine design and evaluation.

negative: Mucin 4 Protects Female Mice from Coronavirus Pathogenesis Using incipient lines of the Collaborative Cross (CC), a murine genetic reference population, we previously identified a quantitative trait loci (QTL) associated with low SARS-CoV titer. In this study, we integrated sequence information and RNA expression of genes within the QTL to identify mucin 4 (Muc4) as a high priority candidate for controlling SARS-CoV titer in the lung. To test this hypothesis, we infected Muc4-/- mice and found that female, but not male, Muc4-/- mice developed more weight loss and disease following infection with SARS-CoV. Female Muc4-/- mice also had more difficulty breathing despite reduced lung pathology; however, no change in viral titers was observed. Comparing across viral families, studies with chikungunya virus, a mosquito-borne arthralgic virus, suggests that Muc4’s impact on viral pathogenesis may be widespread. Although not confirming the original titer QTL, our data identifies a role for Muc4 in the SARS-CoV disease and viral pathogenesis. Importance Given the recent emergence of SARS-CoV-2, this work suggest that Muc4 expression plays a protective role in female mice not conserved in male mice following SARS-CoV infection. With the SARS-CoV-2 outbreak continuing, treatments that modulate or enhance Muc4 activity may provide an avenue for treatment and improved outcomes. In addition, the work highlights the importance of studying host factors including host genetics and biological sex as key parameters influencing infection and disease outcomes.

negative: Livestock infectious diseases and zoonoses. Infectious diseases of livestock are a major threat to global animal health and welfare and their effective control is crucial for agronomic health, for safeguarding and securing national and international food supplies and for alleviating rural poverty in developing countries. Some devastating livestock diseases are endemic in many parts of the world and threats from old and new pathogens continue to emerge, with changes to global climate, agricultural practices and demography presenting conditions that are especially favourable for the spread of arthropod-borne diseases into new geographical areas. Zoonotic infections that are transmissible either directly or indirectly between animals and humans are on the increase and pose significant additional threats to human health and the current pandemic status of new influenza A (H1N1) is a topical example of the challenge presented by zoonotic viruses. In this article, we provide a brief overview of some of the issues relating to infectious diseases of livestock, which will be discussed in more detail in the papers that follow.

negative: Renin-angiotensin-aldosterone system and COVID-19 infection Summary With the multiplication of COVID-19 cases due to SARS COV2, some concerns about angiotensin-converting enzyme 1 (ACE1) inhibitors (ACEi) and angiotensin II type 1 receptor blockers (ARB) have emerged. Because SARS COV2 utilizes ACE2 (angiotensin-converting enzyme 2) as a membrane receptor to enter target cells, the fear that ACEi or ARB might increase the risk of developing severe or fatal severe acute respiratory syndrome in case of COVID-19 infection emerged. The present article discusses these concerns. ACE2 is a membrane-bound enzyme (carboxypeptidase) that contributes to the inactivation of angiotensin II and therefore physiologically counters angiotensin II effects. Due to different structural structures with ACE1, ACE2 is insensitive to ACEIs. Although ARBs and ACEi have been shown to upregulate ACE2 tissue expression in experimental animals, evidence was not always consistent in human studies. Therefore, to date, the exact impact of bot ARBs and ACEis on COVID-19 infection remains unknown and preliminary results are in favor of a protective role of ACEis and ARBs. Finally, some studies support the hypothesis that elevated ACE2 membrane expression and tissue activity by administration of ARB and/or infusion of soluble ACE2 could confer protective properties against inflammatory tissue damage in COVID-19 infection. In summary, based on the currently available evidence and as recommended by several medical societies, ACEi or ARB should not be discontinued because of concerns with COVID-19 infection, except when the hemodynamic situation is precarious and case-by-case adjustment is required.

negative: Local risk perception enhances epidemic control As infectious disease outbreaks emerge, public health agencies often enact vaccination and social distancing measures to slow transmission. Their success depends on not only strategies and resources, but also public adherence. Individual willingness to take precautions may be influenced by global factors, such as news media, or local factors, such as infected family members or friends. Here, we compare three modes of epidemiological decision-making in the midst of a growing outbreak using network-based mathematical models that capture plausible heterogeneity in human contact patterns. Individuals decide whether to adopt a recommended intervention based on overall disease prevalence, the proportion of social contacts infected, or the number of social contacts infected. While all strategies can substantially mitigate transmission, vaccinating (or self isolating) based on the number of infected acquaintances is expected to prevent the most infections while requiring the fewest intervention resources. Unlike the other strategies, it has a substantial herd effect, providing indirect protection to a large fraction of the population.

negative: Flash Survey on SARS-CoV-2 Infections in Pediatric Patients on anti-Cancer Treatment Abstract Introduction Since the beginning of COVID-19 pandemics, it is known that the severe course of the disease occurs mostly among elderly, whereas it is rare among children and young adults. Comorbidities, in particular diabetes and hypertension, clearly associated with age, besides obesity and smoke are strongly associated with the need of intensive treatment and a dismal outcome. A weaker immunity of the elderly has been proposed as a possible explanation of this uneven age distribution. Along the same line, anecdotal information from Wuhan, China mentioned a severe course of COVID-19 in a child treated for leukemia. Aim and methods We made a flash survey on COVID19 incidence and severity among children on anticancer treatment. Respondents were asked by email to fill in a short web based survey. Results We received reports from 25 countries, where approximately 10,000 patients at risk are followed. At the time of the survey, over 200 of these children were tested, nine of whom were positive for COVID-19. Eight of the nine cases had asymptomatic to mild disease and one was just diagnosed with COVID-19. We also discuss preventive measures that are in place or should be taken as well as treatment options in immunocompromised children with COVID-19. Conclusion Thus, even children receiving anti-cancer chemotherapy may have a mild or asymptomatic course of COVID-19. While we should not underestimate the risk of developing a more severe course of COVID-19 than observed here, the intensity of preventive measures should not cause delays or obstructions in oncological treatment.

negative: Outbreak of SARS-CoV2: Pathogenesis of infection and cardiovascular involvement Since the new coronavirus SARS (SARS-CoV2) has emerged from china, the infection (COVID-19) has affected many countries and led to many deaths worldwide. Like SARS-CoV, ACE2 as a functional receptor for SARS-CoV2 is essential for virus to entry to the cell. ACE2 is a part of RAS which is expressed in several organs that opposes the AngII functions by converting Ang II to Ang (1-7), the one with vasodilation effects. The death rate of COVID-19 is estimated about 3.4%, however, some comorbid conditions like underlying cardiovascular disease, hypertension, and diabetes increase the risk of mortality. In addition, cardiovascular involvement by SARS-CoV2 could be direct through either ACE2 receptors which are expressed tremendously in heart, or by the surge of different cytokines or by ARDS-induced hypoxia. Traditional risk factors could aggravate the process of COVID-19 infection that urges the triage of these high risk patients for SARS-CoV2. Currently, there is no effective, proven treatment or vaccination for COVID-19, but many investigators are struggling to find a treatment strategy as soon as possible. Some potential medications like chloroquine by itself or in combination with azithromycin, and some protease inhibitors used for the treatment of COVID-19 have cardiovascular adverse effects that should be kept in mind in order to close monitor of the patients receiving these medications.

negative: Recombinant tandem epitope vaccination provides cross protection against Actinobacillus pleuropneumoniae challenge in mice Actinobacillus pleuropneumoniae (A. pleuropneumoniae/APP) is the pathogen that causes porcine contagious pleuropneumonia. Actinobacillus pleuropneumoniae is divided into 18 serovars, and the cross protection efficacy of epitopes is debatable, which has resulted in the slow development of a vaccine. Consequently, epitope-based vaccines conferring Actinobacillus pleuropneumoniae cross protection have rarely been reported. In this study, B cell epitopes in the head domain of trimeric autotransporter adhesin were predicted, and 6 epitopes were selected. Then, the predicted epitopes (Ba1, Bb5, C1, PH1 and PH2) were connected by linkers to construct a recombinant tandem antigen (rta) gene. The RTA protein encoded by the recombinant rta gene was expressed, and finally the ICR mice were immunized with the RTA protein with or without inactivated Actinobacillus pleuropneumoniae (serovars 1 and 5b) and challenged with Actinobacillus pleuropneumoniae to evaluate the protective effect of the epitope-based vaccine and combined vaccine. The mice in the RTA-immunized group and RTA plus inactivated Actinobacillus pleuropneumoniae vaccine group had a significant improvement in clinical symptoms and a higher level of antibody in the serum than those in the control group. The RTA immune group had a 40% survival rate after Actinobacillus pleuropneumoniae infection, whereas the combination of RTA and inactivated Actinobacillus pleuropneumoniae produced very strong cross immune protection in mice, at least 50% (RTA IB1 + C5) and at most 100% (RTA IB5 + C1), whereas no cross immunoprotection was found in the solo Actinobacillus pleuropneumoniae immune group. Overall, the combination of the RTA protein and inactivated bacteria significantly enhanced the cross protection effects. This implies that RTA protein in combination with a suitable inactivated Actinobacillus pleuropneumoniae strain could be a candidate vaccine for porcine contagious pleuropneumonia.

negative: Coronavirus: the geriatric emergency of 2020. Joint document of the Section on Geriatric Cardiology of the Spanish Society of Cardiology and the Spanish Society of Geriatrics and Gerontology Abstract SARS-CoV-2 infection, also known as COVID-19 (coronavirus infectious disease-19), was first identified in December 2019. In Spain, the first case of this infection was diagnosed on 31 January, 2020 and, by 15 April 2020, has caused 18579 deaths, especially in the elderly. Due to the rapidly evolving situation regarding this disease, the data reported in this article may be subject to modifications. The older population are particularly susceptible to COVID-19 infection and to developing severe disease. The higher morbidity and mortality rates in older people have been associated with comorbidity, especially cardiovascular disease, and frailty, which weakens the immune response. Due to both the number of affected countries and the number of cases, the current situation constitutes an ongoing pandemic and a major health emergency. Because Spain has one of the largest older populations in the world, COVID-19 has emerged as a geriatric emergency. This document has been prepared jointly between the Geriatric Cardiology Section of the Spanish Society of Cardiology and the Spanish Society of Geriatrics and Gerontology.

negative: Individual risk management strategy and potential therapeutic options for the COVID-19 pandemic Abstract It is an ugly fact that a significant amount of the world's population will contract SARS-CoV infection with the current spreading. While specific treatment is not yet coming soon, individual risk assessment and management strategies are crucial. The individual preventive and protective measures drive the personal risk of getting the disease. Among the virus-contracted hosts, their different metabolic status, as determined by their diet, nutrition, age, sex, medical conditions, lifestyle, and environmental factors, govern the personal fate toward different clinical severity of COVID-19, from asymptomatic, mild, moderate, to death. The careful individual assessment for the possible dietary, nutritional, medical, lifestyle, and environmental risks, together with the proper relevant risk management strategies, is the sensible way to deal with the pandemic of SARS-CoV-II.

negative: COVID-19: Epidemiology, Evolution, and Cross-Disciplinary Perspectives The recent outbreak of COVID-19 in Wuhan turned into a public health emergency of international concern. With no antiviral drugs nor vaccines, and the presence of carriers without obvious symptoms, traditional public health intervention measures are significantly less effective. Here, we report the epidemiological and virological characteristics of the COVID-19 outbreak. Originated in bats, 2019-nCoV/ severe acute respiratory syndrome coronavirus (SARS-CoV)-2 likely experienced adaptive evolution in intermediate hosts before transfer to humans at a concentrated source of transmission. Similarities of receptor sequence binding to 2019-nCoV between humans and animals suggest a low species barrier for transmission of the virus to farm animals. We propose, based on the One Health model, that veterinarians and animal specialists should be involved in a cross-disciplinary collaboration in the fight against this epidemic.

negative: A new threat from an old enemy: Re-emergence of coronavirus (Review) The new outbreak of coronavirus from December 2019 has brought attention to an old viral enemy and has raised concerns as to the ability of current protection measures and the healthcare system to handle such a threat. It has been known since the 1960s that coronaviruses can cause respiratory infections in humans; however, their epidemic potential was understood only during the past two decades. In the present review, we address current knowledge on coronaviruses from a short history to epidemiology, pathogenesis, clinical manifestation of the disease, as well as treatment and prevention strategies. Although a great amount of research and efforts have been made worldwide to prevent further outbreaks of coronavirus-associated disease, the spread and lethality of the 2019 outbreak (COVID-19) is proving to be higher than previous epidemics on account of international travel density and immune naivety of the population. Only strong, joint and coordinated efforts of worldwide healthcare systems, researchers, and pharmaceutical companies and receptive national leaders will succeed in suppressing an outbreak of this scale.

negative: 33 Viral Respiratory Infections Abstract Acute respiratory illnesses are the most frequently occurring illness in all age groups globally. Disease is mostly limited to the upper airways and is self-limiting, but a small percentage can progress to lower respiratory tract infections as bronchiolitis and pneumonia. Children and elderly people are at increased risk, especially in developing countries. The most important etiologic agents of severe lower respiratory illness are bacteria such as Streptococcus pneumoniae and Haemophilus influenzae and viruses such as respiratory syncytial virus (RSV) and influenza virus. Efficacious vaccines are available against the two bacteria and the influenza virus. Viruses are much more important in mild upper and middle respiratory tract infections and in bronchiolitis in children, whereas bacteria are the main cause of pneumonia, especially in adults. Clinical syndromes overlap considerably, and there is increasing evidence of bacterial-viral co-infections and of bacterial pneumonia being secondary to viral respiratory tract infection.

negative: Antimikrobielle und antiinfektiöse Maßnahmen

negative: Could an endo-lysosomal ion channel be the Achilles heel of SARS-CoV2? Abstract The ongoing SARS-CoV2 outbreak has developed into a global pandemic. Despite previous outbreaks of SARS-CoV and the related MERS-CoV in recent years, neither a vaccine nor any other medication for an effective treatment are currently available. Endo-lysosomal two-pore cation channels have now emerged as potential novel targets for SARS-CoV treatment.

negative: COVID-19 pneumonia: A review of typical CT findings and differential diagnosis Abstract The standard of reference for confirming COVID-19 relies on microbiological tests such as real-time polymerase chain reaction (RT-PCR) or sequencing. However, these tests might not be available in an emergency setting. Computed tomography (CT) can be used as an important complement for the diagnosis of COVID-19 pneumonia in the current epidemic context. In this review, we present the typical CT features of COVID-19 pneumonia and discuss the main differential diagnosis.

negative: Integrated Cross-Species Analysis Identifies a Conserved Transitional Dendritic Cell Population Plasmacytoid dendritic cells (pDCs) are sensor cells with diverse immune functions, from type I interferon (IFN-I) production to antigen presentation, T cell activation, and tolerance. Regulation of these functions remains poorly understood but could be mediated by functionally specialized pDC subpopulations. We address pDC diversity using a high-dimensional single-cell approach: mass cytometry (CyTOF). Our analysis uncovers a murine pDC-like population that specializes in antigen presentation with limited capacity for IFN-I production. Using a multifaceted cross-species comparison, we show that this pDC-like population is the definitive murine equivalent of the recently described human AXL(+) DCs, which we unify under the name transitional DCs (tDCs) given their continuum of pDC and cDC2 characteristics. tDCs share developmental traits with pDCs, as well as recruitment dynamics during viral infection. Altogether, we provide a framework for deciphering the function of pDCs and tDCs during diseases, which has the potential to open new avenues for therapeutic design.

negative: Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) Publisher Summary Severe acute respiratory syndrome (SARS) is caused by a coronavirus (CoV), SARSCoV. SARS-CoV belongs to the family Coronaviridae, which are enveloped RNA viruses in the order Nidovirales. Global research efforts are continuing to increase the understanding of the virus, the pathogenesis of the disease it causes (SARS), and the “heterogeneity of individual infectiousness” as well as shedding light on how to prepare for other emerging viral diseases. Promising drugs and vaccines have been identified. The milestones achieved have resulted from a truly international effort. Molecular studies dissected the adaptation of this virus as it jumped from an intermediary animal, the civet, to humans, thus providing valuable insights into processes of molecular emergence.

negative: Perspectives on the epizootiology of feline enteric coronavirus and the pathogenesis of feline infectious peritonitis Abstract This review presents some current thoughts regarding teh epizootiology of the feline coronaviruses; feline infectious peritonisis virus (FIPV) and feline coronavirus (FEVC), with primary emphasis on the pathogenesis of these viruses in nature. Although the mechanism(s) whereby FIPV causes disease are still incompletely understood, there have been significant contributions to the literature over the past decade which provide a framework upon which plausible explanations can be postulated. Two concepts are presented which attempt to clarify the pathogenesis of FIPV and at the same time may serve as an impetus for further research. The first involves the hypothesis, originally promulgated by Pedersen in 19891, that FIPV is derived from FECV during virus replication in the gastrointestinal tract. The second involves a unique mechanism of the mucosal immune system referred to as oral tolerance, which under normal conditions promotes the production of secretory immunity and suppresses the production of systematic immunity. In the case of FIPV infection, we propose that oral tolerance is important in the control of the virus at the gastrointestinal tract level. Once oral tolerance is disrupted, FIPV is capable of systemic spread resulting in immune-mediated vasculitis and death. Thus, it may be that clinical forms of FIP are due to a combination of two events, the first being the generation of FIPV from FECV, and the second being the capacity of FIPV to circumvent oral tolerance.

negative: A decade after SARS: Strategies to control emerging coronaviruses Two novel coronaviruses have emerged in humans in the 21(st) century, Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) and Middle East Respiratory Syndrome human coronavirus (MERS-CoV), both of which cause acute respiratory distress syndrome (ARDS) and have high mortality rates. There are no clinically approved vaccines or antiviral drugs available for either of these infections; thus, a priority in the field is the development of effective therapeutic and preventive strategies that can be readily applied to new emergent strains. This review will: describe the emergence and identification of novel human coronaviruses over the last 10 years; review their key biological features, including tropism and receptor use; and summarize approaches to develop broadly effective vaccines.

negative: Characterizing the Transmission Potential of Zoonotic Infections from Minor Outbreaks The transmission potential of a novel infection depends on both the inherent transmissibility of a pathogen, and the level of susceptibility in the host population. However, distinguishing between these pathogen- and population-specific properties typically requires detailed serological studies, which are rarely available in the early stages of an outbreak. Using a simple transmission model that incorporates age-stratified social mixing patterns, we present a novel method for characterizing the transmission potential of subcritical infections, which have effective reproduction number R<1, from readily available data on the size of outbreaks. We show that the model can identify the extent to which outbreaks are driven by inherent pathogen transmissibility and pre-existing population immunity, and can generate unbiased estimates of the effective reproduction number. Applying the method to real-life infections, we obtained accurate estimates for the degree of age-specific immunity against monkeypox, influenza A(H5N1) and A(H7N9), and refined existing estimates of the reproduction number. Our results also suggest minimal pre-existing immunity to MERS-CoV in humans. The approach we describe can therefore provide crucial information about novel infections before serological surveys and other detailed analyses are available. The methods would also be applicable to data stratified by factors such as profession or location, which would make it possible to measure the transmission potential of emerging infections in a wide range of settings.

negative: Human Bocavirus Infection, Canada Human Bocavirus was detected in 18 (1.5%) of 1,209 respiratory specimens collected in 2003 and 2004 in Canada. The main symptoms of affected patients were cough (78%), fever (67%), and sore throat (44%). Nine patients were hospitalized; of these, 8 (89%) were <5 years of age.

negative: Enteric Viral Infections of Calves and Passive Immunity 1 Abstract At least eight viruses have been identified, four within the last 5 yr, that produce diarrhea and pathological intestinal lesions in experimentally inoculated calves. Coronavirus and rotavirus frequently are associated with the neonatal calf diarrhea syndrome, but the etiologic role of the newly identified viruses is undefined. All diarrheal viruses replicate within small intestinal epithelial cells, resulting in variable degrees of villous atrophy. Immunity against these viral infections, therefore, must be directed toward protection of the susceptible intestinal epithelial cells. Because most of these viral infections occur in calves<3 wk of age, passive lactogenic immunity within the gut lumen plays an important role in protection. This report reviews methods of boosting rotavirus antibody responses in bovine mammary secretions and analyses of passive and active immunity in calves supplemented with colostrum and challenged by rotavirus. Results indicate rotavirus immunoglobulin G1 antibodies in colostrum and milk were elevated after intramuscular and intramammary vaccination of pregnant cows with an Ohio Agricultural Research and Development Center rotavirus vaccine but not after intramuscular immunization with a commercial rota-coronavirus vaccine. Feeding colostrum from intramuscular plus intramammary immunized cows to newborn calves challenged by rotavirus prevented diarrhea and shedding of rotavirus.

negative: Covid-19 Pandemic and Current Medical Interventions Abstract First humanoid coronavirus was discovered in the middle of 1960s, the class of viruses are considered to be a huge threat. The first onset of human coronavirus, SARS (SARS-CoV) appeared in 2003 which spanned five continents having lethal effects on human population accompanied by The Middle East Respiratory Syndrome Coronavirus in 2012 with a death rate of 35%. The viruses remain a threat till date and are of serious concern since no vaccine or specified drug therapy has been approbated for treating human coronaviruses. The viruses became a pandemic worldwide with the emergence of Wuhan coronavirus (2019-nCoV). SARS-CoV2 viral manifestation poses a serious human life risk by causing acute lung injury and various respiratory outcomes and has become a global concern. High pathogenicity and transmission rate of the viral strain has become the spotlight of research community throughout the world. With the ongoing studies on viral structure and host interactions, the intricacy of the viral proteome structure and replication cycle proposes a need to explore our understanding of host factors playing role in viral multiplication cycle. This review provides insight into our prevalent perception of coronavirus-host interactions, structure of SARS-CoV2, receptor mediated entry of virus inside the human cells, ongoing clinical trials and drug therapies and treatments that are being used to combat COVID-19 targeting viral fusion, replication and its multiplication.

negative: COVID-19 infection and rheumatoid arthritis: Faraway, so close! Abstract The outbreak of the new coronavirus infections COVID-19 in December 2019 in China has quickly become a global health emergency. Given the lack of specific anti-viral therapies, the current management of severe acute respiratory syndrome coronaviruses (SARS-CoV-2) is mainly supportive, even though several compounds are now under investigation for the treatment of this life-threatening disease. COVID-19 pandemic is certainly conditioning the treatment strategy of a complex disorder as rheumatoid arthritis (RA), whose infectious risk is increased compared to the general population because of an overall impairment of immune system typical of autoimmune diseases combined with the iatrogenic effect generated by corticosteroids and immunosuppressive drugs. However, the increasing knowledge about the pathophysiology of SARS-CoV-2 infection is leading to consider some anti-rheumatic drugs as potential treatment options for the management of COVID-19. In this review we will critically analyse the evidences on either positive or negative effect of drugs commonly used to treat RA in this particular scenario, in order to optimize the current approach to RA patients.

negative: MIDDLE EAST RESPIRATORY SYNDROME VACCINES The Middle East Respiratory Syndrome-coronavirus (MERS-CoV) has infected over 1600 individuals with nearly 600 deaths since it was first identified in human populations in 2012. No anti-viral therapies or vaccines for treatment and prophylaxis are available. Here, we discuss approaches to developing MERS vaccines, including a summary of previous efforts to develop vaccines useful against human and non-human coronaviruses. A striking feature of MERS is the important role that camels have in transmission. Camel vaccination may be a novel approach to preventing the human infection.

negative: Receptor-binding domains of spike proteins of emerging or re-emerging viruses as targets for development of antiviral vaccines A number of emerging and re-emerging viruses have caused epidemics or pandemics of infectious diseases leading to major devastations throughout human history. Therefore, developing effective and safe vaccines against these viruses is clearly important for the protection of at-risk populations. Our previous studies have shown that the receptor-binding domain (RBD) in the spike protein of severe acute respiratory syndrome (SARS)-associated coronavirus (SARS-CoV) is a key target for the development of SARS vaccines. In this review, we highlight some key advances in the development of antiviral vaccines targeting the RBDs of spike proteins of emerging and re-emerging viruses, using SARS-CoV, influenza virus, Hendra virus (HeV) and Nipah virus (NiV) as examples.

negative: Structural analysis of major species barriers between humans and palm civets for severe acute respiratory syndrome coronavirus infections. It is believed that a novel coronavirus, severe acute respiratory syndrome coronavirus (SARS-CoV), was passed from palm civets to humans and caused the epidemic of SARS in 2002 to 2003. The major species barriers between humans and civets for SARS-CoV infections are the specific interactions between a defined receptor-binding domain (RBD) on a viral spike protein and its host receptor, angiotensin-converting enzyme 2 (ACE2). In this study a chimeric ACE2 bearing the critical N-terminal helix from civet and the remaining peptidase domain from human was constructed, and it was shown that this construct has the same receptor activity as civet ACE2. In addition, crystal structures of the chimeric ACE2 complexed with RBDs from various human and civet SARS-CoV strains were determined. These structures, combined with a previously determined structure of human ACE2 complexed with the RBD from a human SARS-CoV strain, have revealed a structural basis for understanding the major species barriers between humans and civets for SARS-CoV infections. They show that the major species barriers are determined by interactions between four ACE2 residues (residues 31, 35, 38, and 353) and two RBD residues (residues 479 and 487), that early civet SARS-CoV isolates were prevented from infecting human cells due to imbalanced salt bridges at the hydrophobic virus/receptor interface, and that SARS-CoV has evolved to gain sustained infectivity for human cells by eliminating unfavorable free charges at the interface through stepwise mutations at positions 479 and 487. These results enhance our understanding of host adaptations and cross-species infections of SARS-CoV and other emerging animal viruses.

negative: Biomimetic nanoparticles as universal influenza vaccine Abstract Pandemic virus infections, such as seasonal influenza, severe acute respiratory syndrome coronavirus and Middle East respiratory syndrome coronavirus, pose a major public health threat globally. 1 , 2 Much effort has been devoted to suppress the virus, including vaccine prevention, autoimmunity enhancement, and anti-virus drugs treatment. Among these strategies, development of novel and improved vaccine technologies attracts broad attention as they can nip the virus outbreak in the bud and avoid the appearance of public health emergency. Therefore, Wang et al. 1 recently offer a promising means: they develop universal viral vaccine through biomimetic nanoparticles.

negative: Studying the effect of chloroquine on sporozoite-induced protection and immune responses in Plasmodium berghei malaria BACKGROUND: Sporozoite immunization of animals and humans under a chemo-prophylactic cover of chloroquine (CPS-CQ) efficiently induces sterile protection against malaria. In humans, CPS-CQ is strikingly more efficient than immunization with radiation attenuated sporozoites (RAS), raising the hypothesis that this might be partially due to CQ. Chloroquine, an established anti-malarial drug, is also well known for its immune modulating properties including improvement of cross-presentation. The aim of this study was to investigate whether co-administration of CQ during sporozoite immunization improves cellular responses and protective efficacy in Plasmodium berghei models. METHODS: A number of experiments in selected complimentary P. berghei murine models in Balb/cByJ and C57BL/6j mice was performed. First, the effect of CQ administration on the induction of protection and immune responses by RAS immunization was studied. Next, the effect of CQ on the induction of circumsporozoite (CS) protein-specific CD8(+) T cells by immunization with P. berghei parasites expressing a mutant CS protein was investigated. Finally, a direct comparison of CPS-CQ to CPS with mefloquine (MQ), an anti-malarial with little known immune modulating effects, was performed. RESULTS: When CQ was co-administered during immunization with graded numbers of RAS, this did not lead to an increase in frequencies of total memory CD8(+) T cells or CS protein-specific CD8(+) T cells. Also parasite-specific cytokine production and protection remained unaltered. Replacement of CQ by MQ for CPS immunization resulted in significantly reduced percentages of IFNγ producing memory T cells in the liver (p = 0.01), but similar protection. CONCLUSIONS: This study does not provide evidence for a direct beneficial effect of CQ on the induction of sporozoite-induced immune responses and protection in P. berghei malaria models. Alternatively, the higher efficiency of CPS compared to RAS might be explained by an indirect effect of CQ through limiting blood-stage exposure after immunization or to increased antigen exposure and, therefore, improved breadth of the immune response. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12936-015-0626-2) contains supplementary material, which is available to authorized users.

negative: Alpha 1 Antitrypsin is an Inhibitor of the SARS-CoV2–Priming Protease TMPRSS2 The transmembrane serine protease TMPRSS2 is indispensable for S protein priming of the MERS, SARS-CoV, and SARS-CoV2 coronaviruses, a process that is necessary for entry of the virus into host cells. Therefore, inhibiting TMPRSS2 holds promise as an approach toward preventing transmission of coronaviruses. Herein, we developed an in vitro system to measure TMPRSS2 activity and tested the inhibition of TMPRSS2 by several synthetic and natural protease inhibitors. Camostat mesylate and bromhexine hydrochloride (BHH) inhibited TMPRSS2 proteolytic function. In addition, we identified the small molecule 4-(2-aminomethyl)benzenesulfonyl fluoride (AEBSF) and the human, anti-inflammatory protein alpha 1 antitrypsin (A1AT) as inhibitors of TMPRSS2. AEBSF and A1AT inhibited TMPRSS2 activity in a dose-dependent manner. AEBSF and A1AT inhibited TMPRSS2 in the same range of concentrations (100-0.1 μM). We suggest that treatment with these inhibitors, particularly A1AT, which is an FDA-approved drug, might be effective in limiting SARS-CoV and SARS-CoV2 transmissibility and as a COVID-19 treatment.

negative: Application prospect of polysaccharides in the development of anti-novel coronavirus drugs and vaccines Since the outbreak of the novel coronavirus disease COVID-19, caused by the SARS-CoV-2 virus, it has spread rapidly worldwide and poses a great threat to public health. This is the third serious coronavirus outbreak in <20 years, following SARS in 2002–2003 and MERS in 2012. So far, there are almost no specific clinically effective drugs and vaccines available for COVID-19. Polysaccharides with good safety, immune regulation and antiviral activity have broad application prospects in anti-virus, especially in anti-coronavirus applications. Here, we reviewed the antiviral mechanisms of some polysaccharides, such as glycosaminoglycans, marine polysaccharides, traditional Chinese medicine polysaccharides, and their application progress in anti-coronavirus. In particular, the application prospects of polysaccharide-based vaccine adjuvants, nanomaterials and drug delivery systems in the fight against novel coronavirus were also analyzed and summarized. Additionally, we speculate the possible mechanisms of polysaccharides anti-SARS-CoV-2, and propose the strategy of loading S or N protein from coronavirus onto polysaccharide capped gold nanoparticles vaccine for COVID-19 treatment. This review may provide a new approach for the development of COVID-19 therapeutic agents and vaccines.

negative: Perspectives on therapeutic neutralizing antibodies against the Novel Coronavirus SARS-CoV-2 A newly identified novel coronavirus (SARS-CoV-2) is causing pneumonia-associated respiratory syndrome across the world. Epidemiology, genomics, and pathogenesis of the SARS-CoV-2 show high homology with that of SARS-CoV. Current efforts are focusing on development of specific antiviral drugs. Therapeutic neutralizing antibodies (NAbs) against SARS-CoV-2 will be greatly important therapeutic agents for the treatment of coronavirus disease 2019 (COVID-19). Herein, the host immune responses against SARS-CoV discussed in this review provide implications for developing NAbs and understanding clinical interventions against SARS-CoV-2. Further, we describe the benefits, challenges and considerations of NAbs against SARS-CoV-2. Although many challenges exist, NAbs still offer a therapeutic option to control the current pandemic and the possible re-emergence of the virus in the future, and their development therefore remains a high priority.

negative: Severe Acute Respiratory Syndrome (SARS) Severe acute respiratory syndrome (SARS) is a new human disease caused by an animal coronavirus that adapted to efficient human-to-human transmission. The disease first emerged in November 2002 in Guangdong Province, China and spread globally within months. The SARS coronavirus (SARS CoV) affects multiple organ systems with severe viral pneumonia as its main clinical manifestation but with diarrhea, lymphopenia, and mild liver dysfunction being common extra-pulmonary manifestations. Increasing age and the presence of underlying respiratory diseases worsens the prognosis. Unlike other respiratory viral infections, transmission of SARS was less frequent in the first 5days of illness and correlated with low viral load in the upper respiratory tract at this stage of the illness. This fortuitous feature of the disease allowed the public health measures of case detection and patient isolation to interrupt virus transmission in the community and abort the SARS outbreak. Bats are a reservoir of a virus closely related to SARS CoV and this may be the likely precursor from which the human-adapted SARS CoV emerged. Small mammals such as ‘civet-cats’ (Paguma larvata) within live animal markets in southern China serve as amplifiers of infection and these markets were the likely interface where zoonotic transmission occurred. The viral spike protein is necessary and sufficient for inducing protective antibody responses and has been a key target in the development of candidate vaccines.

negative: Infecciones en el deportista de elite: gastroenteritis aguda infecciosa e infecciones respiratorias víricas comunes

negative: Wuhan novel coronavirus (COVID-19): why global control is challenging?

negative: A Vaccine of L2 Epitope Repeats Fused with a Modified IgG1 Fc Induced Cross-Neutralizing Antibodies and Protective Immunity against Divergent Human Papillomavirus Types Current human papillomavirus (HPV) major capsid protein L1 virus-like particles (VLPs)-based vaccines in clinic induce strong HPV type-specific neutralizing antibody responses. To develop pan-HPV vaccines, here, we show that the fusion protein E3R4 consisting of three repeats of HPV16 L2 aa 17–36 epitope (E3) and a modified human IgG1 Fc scaffold (R4) induces cross-neutralizing antibodies and protective immunity against divergent HPV types. E3R4 was expressed as a secreted protein in baculovirus expression system and could be simply purified by one step Protein A affinity chromatography with the purity above 90%. Vaccination of E3R4 formulated with Freunds adjuvant not only induced cross-neutralizing antibodies against HPV pseudovirus types 16, 18, 45, 52, 58, 6, 11 and 5 in mice, but also protected mice against vaginal challenges with HPV pseudovirus types 16, 45, 52, 58, 11 and 5 for at least eleven months after the first immunization. Moreover, vaccination of E3R4 formulated with FDA approved adjuvant alum plus monophosphoryl lipid A also induced cross-neutralizing antibodies against HPV types 16, 18 and 6 in rabbits. Thus, our results demonstrate that delivery of L2 antigen as a modified Fc-fusion protein may facilitate pan-HPV vaccine development.

negative: When Viruses Don’t Go Viral: The Importance of Host Phylogeographic Structure in the Spatial Spread of Arenaviruses Many emerging infections are RNA virus spillovers from animal reservoirs. Reservoir identification is necessary for predicting the geographic extent of infection risk, but rarely are taxonomic levels below the animal species considered as reservoir, and only key circumstances in nature and methodology allow intrinsic virus-host associations to be distinguished from simple geographic (co-)isolation. We sampled and genetically characterized in detail a contact zone of two subtaxa of the rodent Mastomys natalensis in Tanzania. We find two distinct arenaviruses, Gairo and Morogoro virus, each spatially confined to a single M. natalensis subtaxon, only co-occurring at the contact zone’s centre. Inter-subtaxon hybridization at this centre and a continuum of quality habitat for M. natalensis show that both viruses have the ecological opportunity to spread into the other substaxon’s range, but do not, strongly suggesting host-intrinsic barriers. Such barriers could explain why human cases of another M. natalensis-borne arenavirus, Lassa virus, are limited to West Africa.

negative: Response and Operating Room Preparation for the COVID-19 Outbreak: A Perspective from the National Heart Centre Singapore Abstract The outbreak of COVID-19, a respiratory disease from a novel coronavirus that was first detected in Wuhan City, Hubei Province, China is now a public health emergency and fast approaching a pandemic. Singapore, as a major international transportation hub in Asia, is one of the worst hit countries of COVID-19. With the advent of local transmission of cases, we share our preparation and response planning for the operating room from the National Heart Centre Singapore, the largest cardiothoracic tertiary center in Singapore. Protection of staff and patients, environmental concerns as well as other logistic and equipment issues must be considered.

negative: Genetic evolution analysis of 2019 novel coronavirus and coronavirus from other species The Corona Virus Disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a Public Health Emergency of International Concern. However, so far, there are still controversies about the source of the virus and its intermediate host. Here, we found the novel coronavirus was closely related to coronaviruses derived from five wild animals, including Paguma larvata, Paradoxurus hermaphroditus, Civet, Aselliscus stoliczkanus and Rhinolophus sinicus, and was in the same branch of the phylogenetic tree. However, genome and ORF1a homology show that the virus is not the same coronavirus as the coronavirus derived from these five animals, whereas the virus has the highest homology with Bat coronavirus isolate RaTG13.

negative: Possible therapeutic role of a highly standardized mixture of active compounds derived from cultured Lentinula edodes mycelia (AHCC) in patients infected with 2019 novel coronavirus The outbreak of SARS-CoV-2 disease (COVID-19) is currently, March 2020, affecting more than 100,000 people worldwide and, according to the WHO (World Health Organization), a pandemic is shortly expected. The virus infects the lower respiratory tract and causes severe pneumonia and mortality in approximately 10% and 3-5%, respectively, of cases, mainly among the elderly and/or people affected by other diseases. AHCC is an α-glucan-based standardized mushroom extract that has been extensively investigated as an immunostimulant both in animals and/or in humans affected by West Nile virus, influenza virus, avian influenza virus, hepatitis C virus, papillomavirus, herpes virus, hepatitis B virus and HIV by promoting a regulated and protective immune response. Although the efficacy of AHCC has not yet been specifically evaluated with respect to SARS-CoV-2 disease, its action in promoting a protective response to a wide range of viral infections, and the current absence of effective vaccines, could support its use in the prevention of diseases provoked by human pathogenic coronavirus, including COVID-19.

negative: Expression and functional characterization of the putative protein 8b of the severe acute respiratory syndrome-associated coronavirus SARS 8b is one of the putative accessory proteins of the severe acute respiratory syndrome-associated coronavirus (SARS-CoV) with unknown functions. In this study, the cellular localization and activity of this estimated 9.6 kDa protein were examined. Confocal microscopy results indicated that SARS 8b is localized in both nucleus and cytoplasm of mammalian cells. Functional study revealed that overexpression of SARS 8b induced DNA synthesis. Coexpression of SARS 8b and SARS 6, a previously characterized SARS-CoV accessory protein, did not elicit synergistic effects on DNA synthesis.

negative: Dynamic changes in circulating T follicular helper cell composition predict neutralising antibody responses after yellow fever vaccination OBJECTIVES: T follicular helper (Tfh) cells are the principal T helper cell subset that provides help to B cells for potent antibody responses against various pathogens. In this study, we took advantage of the live‐attenuated yellow fever virus (YFV) vaccine strain, YF‐17D, as a model system for studying human antiviral immune responses in vivo following exposure to an acute primary virus challenge under safe and highly controlled conditions, to comprehensively analyse the dynamics of circulating Tfh (cTfh) cells. METHODS: We tracked and analysed the response of cTfh and other T and B cell subsets in peripheral blood of healthy volunteers by flow cytometry over the course of 4 weeks after YF‐17D vaccination. RESULTS: Using surface staining of cell activation markers to track YFV‐specific T cells, we found increasing cTfh cell frequencies starting at day 3 and peaking around 2 weeks after YF‐17D vaccination. This kinetic was confirmed in a subgroup of donors using MHC multimer staining for four known MHC class II epitopes of YF‐17D. The subset composition of cTfh cells changed dynamically during the course of the immune response and was dominated by the cTfh1‐polarised subpopulation. Importantly, frequencies of cTfh1 cells correlated with the strength of the neutralising antibody response, whereas frequencies of cTfh17 cells were inversely correlated. CONCLUSION: In summary, we describe detailed cTfh kinetics during YF‐17D vaccination. Our results suggest that cTfh expansion and polarisation can serve as a prognostic marker for vaccine success. These insights may be leveraged in the future to improve current vaccine design and strategies.

negative: Pangolin homology associated with 2019-nCoV To explore potential intermediate host of a novel coronavirus is vital to rapidly control continuous COVID-19 spread. We found genomic and evolutionary evidences of the occurrence of 2019-nCoV-like coronavirus (named as Pangolin-CoV) from dead Malayan Pangolins. Pangolin-CoV is 91.02% and 90.55% identical at the whole genome level to 2019-nCoV and BatCoV RaTG13, respectively. Pangolin-CoV is the lowest common ancestor of 2019-nCoV and RaTG13. The S1 protein of Pangolin-CoV is much more closely related to 2019-nCoV than RaTG13. Five key amino-acid residues involved in the interaction with human ACE2 are completely consistent between Pangolin-CoV and 2019-nCoV but four amino-acid mutations occur in RaTG13. It indicates Pangolin-CoV has similar pathogenic potential to 2019-nCoV, and would be helpful to trace the origin and probable intermediate host of 2019-nCoV.

negative: Emerging threats from zoonotic coronaviruses-from SARS and MERS to 2019-nCoV

negative: Immune response and onset of protection from Bovine viral diarrhea virus 2 infection induced by modified-live virus vaccination concurrent with injectable trace minerals administration in newly received beef calves Abstract Strategies to improve the onset of protective immunity induced by vaccination against respiratory pathogens may have a significant impact on health of newly received beef calves. The objective was to determine if the use of injectable trace minerals (ITM; Se, Zn, Cu, and Mn) concurrent with a modified-live virus (MLV) vaccine enhances the immune response and onset of protection in beef calves challenged with BVDV2 five days after vaccination. Forty-five calves were randomly assigned to one of three groups (15/group): VAC + ITM, received MLV-vaccine and ITM (Multimin®90) subcutaneously (SC); VAC + SAL, received the same vaccine and saline SC; or UNVAC, unvaccinated. Five days after vaccination (d.0), calves were challenged with BVDV2 strain 890. Health status was evaluated and blood samples were collected for leukocyte counts, BVDV1 and 2 serum neutralizing antibody (SNA), BVDV-PCR, percentage of CD4+, CD8+, WC1+ and CD25+ T-cells. VAC + ITM had lower health scores than UNVAC (d.8 and 9). VAC + ITM had higher BVDV1 & 2 SNA titers than VAC + SAL and UNVAC on d.21 and 28. Lymphocyte counts decreased in UNVAC but not in VAC + ITM or VAC + SAL (d.3 to 11). CD4+ T-cells significantly decreased in UNVAC and VAC + SAL (d.3). VAC + ITM had higher percentage of CD4+ cells than UNVAC (d.3 and 7). VAC + ITM had lower percentage of activated CD4+ and CD8+ than UNVAC (d.7). In summary, vaccination induced a rapid protection against BVDV2 infection. Administration of ITM was associated with increased SNA response to BVDV1 & 2, enhanced health status, mitigation of CD4+ T-cells decreased, and reduction of T-cell activation in calves challenged with BVDV2 five days after immunization. These results support the strategic use of ITM concurrent with vaccination, especially when a rapid protection is needed in newly received beef calves.

negative: Murine coronavirus-induced encephalomyelitides in rats: Analysis of immunoglobulins and virus-specific antibodies in serum and cerebrospinal fluid Abstract The humoral intrathecal immune response in coronavirus-induced demyelinating encephalomyelitis in rats associated with an autoimmune reaction to brain antigen, was analysed. The CSF of these animals revealed immune reactions which were directed against coronavirus and other, unknown, antigens. In general, no direct correlation between the disease, the state of the blood-brain barrier (BBB), intrathecal synthesis of Ig and the presence of virus-specific antibodies was detectable, suggesting that the humoral, in contrast to the cellular, immune response does not play a significant pathogenetic role in this CNS disease.

negative: Pay attention to situation of SARS-CoV-2 and TCM advantages in treatment of novel coronavirus infection Since the outbreak of the new coronavirus epidemic, novel coronavirus has infected nearly 100,000 people in more than 110 countries. How to face this new coronavirus epidemic outbreak is an important issue. Basic reproduction number (R0) is an important parameter in epidemiology; The basic reproduction number of an infection can be thought of as the expected number of cases directly generated by one case in a population where all individuals are susceptible to infection. Epidemiology dynamics is a mathematical model based on a susceptibility-infection-recovery epidemic model. Researchers analyzed the epidemiological benefits of different transmission rates for the establishment of effective strategy in prevention and control strategies for epidemic infectious diseases. In this review, the early use of TCM for light and ordinary patients, can rapidly improve symptoms, shorten hospitalization days and reduce severe cases transformed from light and normal. Many TCM formulas and products have wide application in treating infectious and non-infectious diseases. The TCM theoretical system of treating epidemic diseases with TCM and the treatment scheme of integrated Chinese and Western medicine have proved their effectiveness in clinical practice. TCM can cure COVID-19 pneumonia, and also shows that the role of TCM in blocking the progress of COVID-19 pneumonia.

negative: Portable and accurate diagnostics for COVID-19: Combined use of the miniPCR thermocycler and a well-plate reader for SARS-CoV-2 virus detection The COVID-19 pandemic has crudely demonstrated the value of massive and rapid diagnostics. By the first week of April, more than 900,000 positive cases of COVID-19 have been reported worldwide, although this number could be greatly underestimated. In the case of an epidemic emergency, the first line of response should be based on commercially available and validated resources. Here, we demonstrate the combined use of the miniPCR, a commercial compact and portable PCR device recently available on the market, and a commercial well-plate reader as a diagnostic system for detecting SARS-CoV-2 nucleic acids. We used the miniPCR to detect and amplify SARS-CoV-2 DNA sequences using the sets of initiators recommended by the World Health Organization for targeting three different regions that encode for the N protein. Prior to amplification, samples were combined with a DNA intercalating reagent (i.e., EvaGreen Dye). Sample fluorescence after amplification was then read using a commercial 96-well plate reader. This straightforward method allows the detection and amplification of SARS-CoV-2 nucleic acids in the range of ~625 to 2 x 105 DNA copies. The accuracy and simplicity of this diagnostics strategy may provide a cost-efficient and reliable alternative for COVID-19 pandemic testing, particularly in underdeveloped regions where RT-qPCR instrument availability may be limited. The portability, ease of use, and reproducibility of the miniPCR makes it a reliable alternative for deployment in point-of-care SARS-CoV-2 detection efforts during pandemics.

negative: Keeping the Country Positive during the COVID 19 Pandemic: Evidence from India

negative: COVID-19 (Novel Coronavirus 2019) - recent trends. The World Health Organization (WHO) has issued a warning that, although the 2019 novel coronavirus (COVID-19) from Wuhan City (China), is not pandemic, it should be contained to prevent the global spread. The COVID-19 virus was known earlier as 2019-nCoV. As of 12 February 2020, WHO reported 45,171 cases and 1115 deaths related to COVID-19. COVID-19 is similar to Severe Acute Respiratory Syndrome coronavirus (SARS-CoV) virus in its pathogenicity, clinical spectrum, and epidemiology. Comparison of the genome sequences of COVID-19, SARS-CoV, and Middle East Respiratory Syndrome coronavirus (MERS-CoV) showed that COVID-19 has a better sequence identity with SARS-CoV compared to MERS CoV. However, the amino acid sequence of COVID-19 differs from other coronaviruses specifically in the regions of 1ab polyprotein and surface glycoprotein or S-protein. Although several animals have been speculated to be a reservoir for COVID-19, no animal reservoir has been already confirmed. COVID-19 causes COVID-19 disease that has similar symptoms as SARS-CoV. Studies suggest that the human receptor for COVID-19 may be angiotensin-converting enzyme 2 (ACE2) receptor similar to that of SARS-CoV. The nucleocapsid (N) protein of COVID-19 has nearly 90% amino acid sequence identity with SARS-CoV. The N protein antibodies of SARS-CoV may cross react with COVID-19 but may not provide cross-immunity. In a similar fashion to SARS-CoV, the N protein of COVID-19 may play an important role in suppressing the RNA interference (RNAi) to overcome the host defense. This mini-review aims at investigating the most recent trend of COVID-19.

negative: Allo-priming as a universal anti-viral vaccine: protecting elderly from current COVID-19 and any future unknown viral outbreak BACKGROUND: We present the rationale for a novel allo-priming approach to serve the elderly as a universal anti-virus vaccine, as well serving to remodel the aging immune system in order to reverse immunosenescence and inflammaging. This approach has the potential to protect the most vulnerable from disease and provide society an incalculable economic benefit. Allo-priming healthy elderly adults is proposed to provide universal protection from progression of any type of viral infection, including protection against progression of the current outbreak of COVID-19 infection, and any future variants of the causative SARS-CoV-2 virus or the next ‘Disease X’. Allo-priming is an alternative approach for the COVID-19 pandemic that provides a back-up in case vaccination strategies to elicit neutralizing antibody protection fails or fails to protect the vulnerable elderly population. The allo-priming is performed using activated, intentionally mismatched, ex vivo differentiated and expanded living Th1-like cells (AlloStim(®)) derived from healthy donors currently in clinical use as an experimental cancer vaccine. Multiple intradermal injections of AlloStim(®) creates a dominate titer of allo-specific Th1/CTL memory cells in circulation, replacing the dominance of exhausted memory cells of the aged immune system. Upon viral encounter, by-stander activation of the allo-specific memory cells causes an immediate release of IFN-ϒ, leading to development of an “anti-viral state”, by-stander activation of innate cellular effector cells and activation of cross-reactive allo-specific CTL. In this manner, the non-specific activation of allo-specific Th1/CTL initiates a cascade of spatial and temporal immune events which act to limit the early viral titer. The release of endogenous heat shock proteins (HSP) and DAMP from lysed viral-infected cells, in the context of IFN-ϒ, creates of conditions for in situ vaccination leading to viral-specific Th1/CTL immunity. These viral-specific Th1/CTL provide sterilizing immunity and memory for protection from disease recurrence, while increasing the pool of Th1/CTL in circulation capable of responding to the next viral encounter. CONCLUSION: Allo-priming has potential to provide universal protection from viral disease and is a strategy to reverse immunosenescence and counter-regulate chronic inflammation (inflammaging). Allo-priming can be used as an adjuvant for anti-viral vaccines and as a counter-measure for unknown biological threats and bio-economic terrorism.

negative: Current status and progress of 2019 novel coronavirus pneumonia/ 中华危重病急救医学 Recently, the 2019 novel coronavirus (2019-nCoV) pneumonia outbroke in Wuhan and rapidly spread to all over China and even the world. Because of the strong infectivity and various clinical symptoms, it has brought certain difficulties to the epidemic prevention and control. Currently there is no specific drug for 2019-nCoV. Previous drugs used to treat other coronaviruses may be effective, but further clinical trials remain needed. We reviewed literature on the epidemiology, etiology, clinical manifestations, imaging manifestations, laboratory examination, diagnosis, complications, treatment and outcome of 2019-nCoV pneumonia.

negative: Flattening the curve before it flattens us: hospital critical care capacity limits and mortality from novel coronavirus (SARS-CoV2) cases in US counties ABSTRACT Background As of March 26, 2020, the United States had the highest number of confirmed cases of Novel Coronavirus (COVID-19) of any country in the world. Hospital critical care is perhaps the most important medical system choke point in terms of preventing deaths in a disaster scenario such as the current COVID-19 pandemic. We therefore brought together previously established disease modeling estimates of the growth of the COVID-19 epidemic in the US under various social distancing contact reduction assumptions, with local estimates of the potential critical care surge response across all US counties. Methods Estimates of spatio-temporal COVID-19 demand and medical system critical care supply were calculated for all continental US counties. These estimates were statistically summarized and mapped for US counties, regions and urban versus non-urban areas. Estimates of COVID-19 infections and patients needing critical care were calculated from March 24, 2020 to April 24, 2020 for three different estimated population levels - 0%, 25%, and 50% - of contact reduction (through actions such as social distancing). Multiple national public and private datasets were linked and harmonized in order to calculate county-level critical care bed counts that included currently available beds and those that could be made available under four surge response scenarios - very low, low, medium, and high - as well as excess deaths stemming from inaccessible critical care. Results Surge response scenarios ranged from a very low total supply 77,588 critical care beds to a high total of 278,850 critical care beds. Over the four week study period, excess deaths from inaccessible critical care ranged from 24,688 in the very low response scenario to 13,268 in the high response scenario. Northeastern and urban counties were projected to be most affected by excess deaths due to critical care shortages, and counties in New York, Colorado, and Virginia were projected to exceed their critical care bed limits despite high levels of COVID-19 contact reduction. Over the four week study period, an estimated 12,203-19,594 excess deaths stemming from inaccessible critical care could be averted through greater preventive actions such as travel restrictions, publicly imposed contact precautions, greater availability of rapid testing for COVID-19, social distancing, self-isolation when sick, and similar interventions. An estimated 4,029-11,420 excess deaths stemming from inaccessible critical care could be averted through aggressive critical care surge response and preparations, including high clearance of ICU and non-ICU critical care beds and extraordinary measures like using a single ventilator for multiple patients. Conclusions Unless the epidemic curve of COVID-19 cases is flattened over an extended period of time, the US COVID-19 epidemic will cause a shortage of critical care beds and drive up otherwise preventable deaths. The findings here support value of preventive actions to flatten the epidemic curve, as well as the value of exercising extraordinary surge capacity measures to increase access to hospital critical care for severely ill COVID-19 patients.

negative: Clinical features and dynamics of viral load in imported and non-imported patients with COVID-19 OBJECTIVES: To compare the clinical characteristics and the dynamics of viral load between imported and non-imported patients with COVID-19. DESIGN AND METHODS: Data from 51 laboratory-confirmed patients were retrospectively analyzed. RESULTS: The incubation period in the tertiary group was longer than that in the imported and secondary groups (both p < 0.05). Fever was the most common symptom at the onset of illness (73.33%, 58.82%, and 68.42%, respectively), and half of the patients had a low-grade temperature (<38.0 °C) with a short duration of fever (<7 days). CT scans showed that most patients in the three groups had bilateral pneumonia (80.00%, 76.47%, and 73.68%, respectively). Ct values detected in the tertiary patients were similar to those for the imported and secondary groups at the time of admission (both p > 0.05). For the tertiary group, the viral load was undetectable in half of the patients (52.63%) on day 7, and in all patients on day 14. For one third of the patients in the imported and secondary groups, the viral load remained positive on day 14 after the admission. CONCLUSIONS: COVID-19 can present as pneumonia with a low onset of symptoms, and the infectivity of SARS-CoV2 may gradually decrease in tertiary patients.

negative: Rapid Detection of COVID-19 Causative Virus (SARS-CoV-2) in Human Nasopharyngeal Swab Specimens Using Field-Effect Transistor-Based Biosensor [Image: see text] Coronavirus disease 2019 (COVID-19) is a newly emerging human infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, previously called 2019-nCoV). Based on the rapid increase in the rate of human infection, the World Health Organization (WHO) has classified the COVID-19 outbreak as a pandemic. Because no specific drugs or vaccines for COVID-19 are yet available, early diagnosis and management are crucial for containing the outbreak. Here, we report a field-effect transistor (FET)-based biosensing device for detecting SARS-CoV-2 in clinical samples. The sensor was produced by coating graphene sheets of the FET with a specific antibody against SARS-CoV-2 spike protein. The performance of the sensor was determined using antigen protein, cultured virus, and nasopharyngeal swab specimens from COVID-19 patients. Our FET device could detect the SARS-CoV-2 spike protein at concentrations of 1 fg/mL in phosphate-buffered saline and 100 fg/mL clinical transport medium. In addition, the FET sensor successfully detected SARS-CoV-2 in culture medium (limit of detection [LOD]: 1.6 × 10(1) pfu/mL) and clinical samples (LOD: 2.42 × 10(2) copies/mL). Thus, we have successfully fabricated a promising FET biosensor for SARS-CoV-2; our device is a highly sensitive immunological diagnostic method for COVID-19 that requires no sample pretreatment or labeling.

negative: Analysis of therapeutic targets for SARS-CoV-2 and discovery of potential drugs by computational methods SARS-CoV-2 has caused tens of thousands of infections and more than one thousand deaths. There are currently no registered therapies for treating coronavirus infections. Because of time consuming process of new drug development, drug repositioning may be the only solution to the epidemic of sudden infectious diseases. We systematically analyzed all the proteins encoded by SARS-CoV-2 genes, compared them with proteins from other coronaviruses, predicted their structures, and built 19 structures that could be done by homology modeling. By performing target-based virtual ligand screening, a total of 21 targets (including two human targets) were screened against compound libraries including ZINC drug database and our own database of natural products. Structure and screening results of important targets such as 3-chymotrypsin-like protease (3CLpro), Spike, RNA-dependent RNA polymerase (RdRp), and papain like protease (PLpro) were discussed in detail. In addition, a database of 78 commonly used anti-viral drugs including those currently on the market and undergoing clinical trials for SARS-CoV-2 was constructed. Possible targets of these compounds and potential drugs acting on a certain target were predicted. This study will provide new lead compounds and targets for further in vitro and in vivo studies of SARS-CoV-2, new insights for those drugs currently ongoing clinical studies, and also possible new strategies for drug repositioning to treat SARS-CoV-2 infections.

negative: COVID-19: Melatonin as a potential adjuvant treatment Abstract This article summarizes the likely benefits of melatonin in the attenuation of COVID-19 based on its putative pathogenesis. The recent outbreak of COVID-19 has become a pandemic with tens of thousands of infected patients. Based on clinical features, pathology, the pathogenesis of acute respiratory disorder induced by either highly homogenous coronaviruses or other pathogens, the evidence suggests that excessive inflammation, oxidation, and an exaggerated immune response very likely contribute to COVID-19 pathology. This leads to a cytokine storm and subsequent progression to acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) and often death. Melatonin, a well-known anti-inflammatory and anti-oxidative molecule, is protective against ALI/ARDS caused by viral and other pathogens. Melatonin is effective in critical care patients by reducing vessel permeability, anxiety, sedation use, and improving sleeping quality, which might also be beneficial for better clinical outcomes for COVID-19 patients. Notably, melatonin has a high safety profile. There is significant data showing that melatonin limits virus-related diseases and would also likely be beneficial in COVID-19 patients. Additional experiments and clinical studies are required to confirm this speculation.

negative: MERS-CoV Spike Protein Vaccine and Inactivated Influenza Vaccine Formulated with Single Strand RNA Adjuvant Induce T-Cell Activation through Intranasal Immunization in Mice The effectiveness of vaccines is enhanced by adding adjuvants. Furthermore, the selection of an inoculation route depends on the type of adjuvant used and is important for achieving optimum vaccine efficacy. We investigated the immunological differences between two types of vaccines—spike protein from the Middle East respiratory syndrome virus and inactivated influenza virus vaccine, in combination with a single-stranded RNA adjuvant—administered through various routes (intramuscular, intradermal, and intranasal) to BALB/c mice. Intramuscular immunization with the RNA adjuvant-formulated spike protein elicited the highest humoral immune response, characterized by IgG1 and neutralizing antibody production. Although intranasal immunization did not elicit a humoral response, it showed extensive T-cell activation through large-scale induction of interferon-γ- and interleukin-2-secreting cells, as well as CD4+ T-cell activation in mouse splenocytes. Moreover, only intranasal immunization induced IgA production. When immunized with the inactivated influenza vaccine, administration of the RNA adjuvant via all routes led to protection after viral challenge, regardless of the presence of a vaccine-specific antibody. Therefore, the inoculation route should depend on the type of immune response needed; i.e., the intramuscular route is suitable for eliciting a humoral immune response, whereas the intranasal route is useful for T-cell activation and IgA induction.

negative: SARS-COV2 INFECTION AND LUNG CANCER PATIENTS: the potential role of IL17 target therapy Abstract The coronavirus disease 2019 (Covid-19) outbreak is evolving rapidly worldwide. The Lung is the target organ of the primary infection and patient whit lung cancer seems to have a poor prognosis. This is the first reported investigation on a possible role of IL 17 target therapy in Lung Cancer patients with concomitant Sars-CoV2 infection.

negative: Pandemic Influenza Due to pH1N1/2009 Virus: Estimation of Infection Burden in Reunion Island through a Prospective Serosurvey, Austral Winter 2009 BACKGROUND: To date, there is little information that reflects the true extent of spread of the pH1N1/2009v influenza pandemic at the community level as infection often results in mild or no clinical symptoms. This study aimed at assessing through a prospective study, the attack rate of pH1N1/2009 virus in Reunion Island and risk factors of infection, during the 2009 season. METHODOLOGY/PRINCIPAL FINDINGS: A serosurvey was conducted during the 2009 austral winter, in the frame of a prospective population study. Pairs of sera were collected from 1687 individuals belonging to 772 households, during and after passage of the pandemic wave. Antibodies to pH1N1/2009v were titered using the hemagglutination inhibition assay (HIA) with titers ≥1/40 being considered positive. Seroprevalence during the first two weeks of detection of pH1N1/2009v in Reunion Island was 29.8% in people under 20 years of age, 35.6% in adults (20–59 years) and 73.3% in the elderly (≥60 years) (P<0.0001). Baseline corrected cumulative incidence rates, were 42.9%, 13.9% and 0% in these age groups respectively (P<0.0001). A significant decline in antibody titers occurred soon after the passage of the epidemic wave. Seroconversion rates to pH1N1/2009 correlated negatively with age: 63.2%, 39.4% and 16.7%, in each age group respectively (P<0.0001). Seroconversion occurred in 65.2% of individuals who were seronegative at inclusion compared to 6.8% in those who were initially seropositive. CONCLUSIONS: Seroincidence of pH1N1/2009v infection was three times that estimated from clinical surveillance, indicating that almost two thirds of infections occurring at the community level have escaped medical detection. People under 20 years of age were the most affected group. Pre-epidemic titers ≥1/40 prevented seroconversion and are likely protective against infection. A concern was raised about the long term stability of the antibody responses.

negative: Dynamic change process of target genes by RT-PCR testing of SARS-Cov-2 during the course of a Coronavirus Disease 2019 patient Abstract We report the dynamic change process of target genes by RT-PCR testing of SARS-Cov-2 during the course of a COVID-19 patient: from successive negative results to successive single positive nucleocapsid gene, to two positive target genes (orf1ab and nucleocapsid) by RT-PCR testing of SARS-Cov-2, and describe the diagnosis, clinical course, and management of the case. In this case, negative results of RT-PCR testing was not excluded to diagnose a suspected COVID-19 patient, clinical signs and symptoms, other laboratory findings, and chest CT images should be taken into account for the absence of enough positive evidence. This case highlights the importance of successive sampling and testing SARS-Cov-2 by RT-PCR as well as the increased value of single positive target gene from pending to positive in two specimens to diagnose laboratory-confirmed COVID-19.

negative: The modelling of COVID19 pathways sheds light on mechanisms, opportunities and on controversial interpretations of medical treatments. v2 The new coronavirus (2019-nCoV or SARS-CoV2), inducing the current pandemic disease (COVID-19) and causing pneumoniae in humans, is dramatically increasing in epidemic scale since its first appearance in Wuhan, China, in December 2019. The first infection from epidemic coronaviruses in 2003 fostered the spread of an overwhelming amount of related scientific efforts. The manifold aspects that have been raised, as well as their redundancy offer precious information that has been underexploited and needs to be critically re-evaluated, appropriately used and offered to the whole community, from scientists, to medical doctors, stakeholders and common people. These efforts will favour a holistic view on the comprehension, prevention and development of strategies (pharmacological, clinical etc) as well as common intervention against the new coronavirus spreading. Here we describe a model that emerged from our analysis that was focused on the Renin Angiotensin System (RAS) and the possible routes linking it to the viral infection. because the infection is mediated by the viral receptor on human cell membranes Angiotensin Converting Enzyme (ACE2), which is a key component in RAS signalling. The model depicts the main pathways determining the disease and the molecular framework for its establishment, and can help to shed light on mechanisms involved in the infection. It promptly gives an answer to some of the controversial, and still open, issues concerning predisposing conditions and medical treatments that protect from or favour the severity of the disease (such as the use of ACE inhibitors or ARBs/sartans), or to the sex related biases in the affected population. The model highlights novel opportunities for further investigations, diagnosis and appropriate intervention to understand and fight COVID19.

negative: Class II-restricted T cell responses in Theiler's murine encephalomyelitis virus (TMEV)-induced demyelinating disease(): III. Failure of neuroantigen-specific immune tolerance to affect the clinical course of demyelination Intracerebral inoculation of Theiler's murine encephalomyelitis virus (TMEV) into susceptible mouse strains produces a chronic demyelinating disease in which mononuclear cell-rich infiltrates in the central nervous system (CNS) are prominent. Current evidence strongly supports an immune-mediated basis for myelin breakdown, with an effector role proposed for TMEV-specific, major histocompatibility complex (MHC) class II-restricted delayed-type hypersensitivity (DTH) responses in which lymphokine-activated macrophages mediate bystander demyelination. The present study examined the possibility that concomitant or later-appearing neuroantigen-specific autoimmune T cell responses, such as those demonstrated in chronic-relapsing experimental allergic encephalomyelitis (R-EAE), may contribute to the demyelinating process following TMEV infection. T cell responses against intact, purified major myelin proteins (myelin basic protein (MBP) and proteolipid protein (PLP), and against altered myelin constituents were readily demonstrable in SJL/J mice with R-EAE, but were not detectable in SJL/J mice with TMEV-induced demyelinating disease. TMEV-infected mice also did not display T cell responses against the peptide fragments of MBP(91–104) and PLP(139–151) recently shown to be encephalitogenic in SJL/J mice. In addition, induction of neuroantigen-specific tolerance to a heterogeneous mixture of CNS antigens, via the i.v. injection of syngeneic SJL/J splenocytes covalently coupled with mouse spinal cord homogenate, resulted in significant suppression of clinical and histologic signs of R-EAE and the accompanying MBP- and PLP-specific DTH responses. In contrast, neuroantigen-specific tolerance failed to alter the development of clinical and histologic signs of TMEV-induced demyelinating disease or the accompanying virus-specific DTH and humoral immune responses. These findings demonstrate that TMEV-induced demyelinating disease can occur in the apparent absence of neuroantigen-specific autoimmune responses. The relationship of the present results to the immunopathology of multiple sclerosis is discussed.

negative: Early Spread of SARS-Cov-2 in the Icelandic Population BACKGROUND Limited data exist on how SARS-CoV-2 enters and spreads in the general population. METHODS We used two strategies for SARS-CoV-2 testing: targeted testing of high-risk individuals (n=4,551) and a population screening (n=5,502). We sequenced SARS-CoV-2 from 340 individuals. RESULTS On March 22 2020, 528 had tested positive for SARS-CoV-2 in the targeted testing (11.6%) and 50 in the population screening (0.9%); approximately 0.2% of the Icelandic population. Large fractions of positives had travelled outside Iceland (38.4% and 34.0%). Fewer under 10 years old were positive than those older: 2.8% vs. 12.3% for targeted testing (P=1.6e-9) and 0.0% vs. 1.0% for population screening (P=0.031). Fewer females were positive in the targeted testing than males (9.5% vs. 14.6%, P=6.8e-9). SARS-CoV-2 came from eight clades, seven A clades and one B clade. The clade composition differed between the testing groups and changed with time. In the early targeted testing, 65.0% of clades were A2a1 and A2a2 derived from Italian and Austrian skiing areas, but in the later targeted testing went down to 30.6% and were overtaken by A1a and A2a, the most common clades in the population screening. CONCLUSION SARS-CoV-2 has spread widely in Iceland outside of the high-risk groups. Several strains cause these infections and their relative contribution changed rapidly. Children and females are less vulnerable than adults and males. To contain the pandemic we must increase the scope of the testing.

negative: Deubiquitinating Enzymes in Coronaviruses and Possible Therapeutic Opportunities for COVID-19 Following the outbreak of novel severe acute respiratory syndrome (SARS)-coronavirus (CoV)2, the majority of nations are struggling with countermeasures to fight infection, prevent spread and improve patient survival. Considering that the pandemic is a recent event, no large clinical trials have been possible and since coronavirus specific drug are not yet available, there is no strong consensus on how to treat the coronavirus disease 2019 (COVID-19) associated viral pneumonia. Coronaviruses code for an important multifunctional enzyme named papain-like protease (PLP), that has many roles in pathogenesis. First, PLP is one of the two viral cysteine proteases, along with 3-chymotripsin-like protease, that is responsible for the production of the replicase proteins required for viral replication. Second, its intrinsic deubiquitinating and deISGylating activities serve to antagonize the host’s immune response that would otherwise hinder infection. Both deubiquitinating and deISGylating functions involve the removal of the small regulatory polypeptides, ubiquitin and ISG15, respectively, from target proteins. Ubiquitin modifications can regulate the innate immune response by affecting regulatory proteins, either by altering their stability via the ubiquitin proteasome pathway or by directly regulating their activity. ISG15 is a ubiquitin-like modifier with pleiotropic effects, typically expressed during the host cell immune response. PLP inhibitors have been evaluated during past coronavirus epidemics, and have showed promising results as an antiviral therapy in vitro. In this review, we recapitulate the roles of PLPs in coronavirus infections, report a list of PLP inhibitors and suggest possible therapeutic strategies for COVID-19 treatment, using both clinical and preclinical drugs.

negative: Identification of protective T-cell antigens for smallpox vaccines Abstract E3L is an immediate-early protein of vaccinia virus that is detected within 0.5 hours of infection, potentially before the many immune evasion genes of vaccinia can exert their protective effects. E3L is highly conserved among orthopoxviruses and hence could provide important protective T-cell epitopes that should be retained in any subunit or attenuated vaccine. We have therefore evaluated the immunogenicity of E3L in healthy VV vaccinated donors. Peripheral blood mononuclear cells from healthy volunteers (n=13) who had previously received a smallpox vaccine (Dryvax®) were activated and expanded using overlapping E3L peptides and their function, specificity and anti-viral activity was analyzed. E3L-specific T-cells were expanded from 7 of 12 (58.3%) vaccinated healthy donors. 25% of these produced CD8+ T-cell responses and 87.5% produced CD4+ T-cells. We identified epitopes restricted by HLA-B35 and HLA-DR15. E3L-specific T-cells killed peptide-loaded target cells as well as vaccinia-infected cells but only CD8+ T-cells could prevent the spread of infectious virus in virus inhibition assays. The epitopes recognized by E3L-specific T-cells were shared with monkeypox and although there was a single amino acid change in the variola epitope homolog, it was recognized by vaccinia-specific T-cells. Therefore it might be important to include E3L in any deletion mutant or subunit vaccine and E3L could provide a useful antigen to monitor protective immunity in humans.

negative: The case for chronotherapy in Covid-19-induced acute respiratory distress syndrome Coronavirus disease 2019 (COVID-19), the disease resulting from infection by a novel coronavirus, SARS-Cov2, has rapidly spread since November 2019 leading to a global pandemic. SARS-Cov2 has infected over four million people and caused over 290,000 deaths worldwide. Although most cases are mild, a subset of patients develop a severe and atypical presentation of acute respiratory distress syndrome (ARDS) that is characterised by a cytokine release storm (CRS). Paradoxically, treatment with anti-inflammatory agents and immune regulators has been associated with worsening of ARDS. We hypothesize that the intrinsic circadian clock of the lung and the immune system may regulate individual components of CRS, and thus, chronotherapy may be used to effectively manage ARDS in COVID-19 patients.

negative: An exclusive 42 amino acid signature in pp1ab protein provides insights into the evolutive history of the 2019 novel human‐pathogenic coronavirus (SARS‐CoV‐2) The city of Wuhan, Hubei province, China, was the origin of a severe pneumonia outbreak in December 2019, attributed to a novel coronavirus (severe acute respiratory syndrome coronavirus 2 [SARS‐CoV‐2]), causing a total of 2761 deaths and 81109 cases (25 February 2020). SARS‐CoV‐2 belongs to genus Betacoronavirus, subgenus Sarbecovirus. The polyprotein 1ab (pp1ab) remains unstudied thoroughly since it is similar to other sarbecoviruses. In this short communication, we performed phylogenetic‐structural sequence analysis of pp1ab protein of SARS‐CoV‐2. The analysis showed that the viral pp1ab has not changed in most isolates throughout the outbreak time, but interestingly a deletion of 8 aa in the virulence factor nonstructural protein 1 was found in a virus isolated from a Japanese patient that did not display critical symptoms. While comparing pp1ab protein with other betacoronaviruses, we found a 42 amino acid signature that is only present in SARS‐CoV‐2 (AS‐SCoV2). Members from clade 2 of sarbecoviruses have traces of this signature. The AS‐SCoV2 located in the acidic‐domain of papain‐like protein of SARS‐CoV‐2 and bat‐SL‐CoV‐RatG13 guided us to suggest that the novel 2019 coronavirus probably emerged by genetic drift from bat‐SL‐CoV‐RaTG13. The implication of this amino acid signature in papain‐like protein structure arrangement and function is something worth to be explored.

negative: Seasonal influenza surveillance: Observational study on the 2017–2018 season with predominant B influenza virus circulation Abstract Introduction Influenza is a common respiratory infectious disease affecting population worldwide yearly. The aim of this work is to describe the 2017–2018 influenza season and how it affected elderly population in Catalonia despite moderate vaccine coverage among this age group. Methods Influenza surveillance based on a primary care sentinel surveillance, virological indicators systematic sampling of ILI attended and severe influenza confirmed cases (SHLCI) admitted to hospital. Analysis of data by Chi-squared, ANOVA, multiple regression and negative control test or case to case for vaccine effectiveness assessment in primary care and SHLCI respectively. Results Moderate-high intensity and early onset season with predominance of influenza B virus (IVB) (63%) followed by an increase of circulation of influenza A virus (IVA). A total of 419 IV from primary care samples. Vaccine effectiveness (VE) in primary care setting was 14% (95%CI: 0–47%). 1306 severe cases (adjusted cumulative incidence 18.54/100,000 inhabitants (95%CI: 17.54–19.55)). The highest proportion of severe cases were in the >64 (65.1%) (aOR 15.70; 95%CI: 12.06–20.46; p <0.001) followed by 45–64yo (25.4%) (aOR 6.03; 95%CI: 4.57–7.97). VE in preventing intensive care unit (ICU) admission was 35% (95%CI: 10–54%). Final outcome death while hospitalized occurred in 175 SHLCI cases with a case fatality rate of 13.4%. Conclusions 2017–2018 influenza season was an unusual epidemic season with an early onset, great predominance of influenza B (Yamagata strain) virus with a high hospitalization rate of severe cases among elderly stressing the need to upgrade vaccine uptake in this age group.

negative: Revisión narrativa sobre la respuesta inmunitaria frente a coronavirus: descripción general, aplicabilidad para SARS-COV-2 e implicaciones terapéuticas./ [Narrative review of the immune response against coronavirus: An overview, applicability for SARS-COV-2, and therapeutic implications] The new coronavirus (SARS-CoV-2) that causes a severe acute respiratory syndrome emerges in Wuhan, China, in December 2019. It produces the aforementioned disease due to coronavirus 2019 (COVID-19), and has led to a declaration of a world public health emergency by the World Health Organisation. This new SARS-CoV-2 virus could share characteristics and an immune response similar to those described for other coronavirus. Given its activity on the interferon pathway, and the manner in which it dysregulates innate immunity, the use of treatments directed at modulating or containing this could be of interest. A narrative review was made of the current evidence about immunity against coronavirus and its applicability to SARS-CoV-2. The physiopathogenesis is also described, along with the underlying leucocyte activity, with the intention of clarifying the possible usefulness of inflammatory biomarkers and the development of personalised treatments.

negative: Society of General Internal Medicine: 28th Annual Meeting New Orleans, LA May 11–14, 2005: Out of Chaos: The Critical Role of Generalists, ABSTRACTS OF SUBMISSIONS ACCEPTED FOR PRESENTATIOIN

negative: Respiratory viral infection in lung transplantation induces exosomes that trigger chronic rejection BACKGROUND Respiratory viral infections can increase the risk of chronic lung allograft dysfunction after lung transplantation, but the mechanisms are unknown. In this study, we determined whether symptomatic respiratory viral infections after lung transplantation induce circulating exosomes that contain lung-associated self-antigens and assessed whether these exosomes activate immune responses to self-antigens. METHODS Serum samples were collected from lung transplant recipients with symptomatic lower- and upper-tract respiratory viral infections and from non-symptomatic stable recipients. Exosomes were isolated via ultracentrifugation; purity was determined using sucrose cushion; and presence of lung self-antigens, 20S proteasome, and viral antigens for rhinovirus, coronavirus, and respiratory syncytial virus were determined using immunoblot. Mice were immunized with circulating exosomes from each group and resulting differential immune responses and lung histology were analyzed. RESULTS Exosomes containing self-antigens, 20S proteasome, and viral antigens were detected at significantly higher levels (p < 0.05) in serum of recipients with symptomatic respiratory viral infections (n = 35) as compared with stable controls (n = 32). Mice immunized with exosomes from recipients with respiratory viral infections developed immune responses to self-antigens, fibrosis, small airway occlusion, and significant cellular infiltration; mice immunized with exosomes from controls did not (p < 0.05). CONCLUSIONS Circulating exosomes isolated from lung transplant recipients diagnosed with respiratory viral infections contained lung self-antigens, viral antigens, and 20S proteasome and elicited immune responses to lung self-antigens that resulted in development of chronic lung allograft dysfunction in immunized mice.

negative: A Recombinant Vaccine of H5N1 HA1 Fused with Foldon and Human IgG Fc Induced Complete Cross-Clade Protection against Divergent H5N1 Viruses Development of effective vaccines to prevent influenza, particularly highly pathogenic avian influenza (HPAI) caused by influenza A virus (IAV) subtype H5N1, is a challenging goal. In this study, we designed and constructed two recombinant influenza vaccine candidates by fusing hemagglutinin 1 (HA1) fragment of A/Anhui/1/2005(H5N1) to either Fc of human IgG (HA1-Fc) or foldon plus Fc (HA1-Fdc), and evaluated their immune responses and cross-protection against divergent strains of H5N1 virus. Results showed that these two recombinant vaccines induced strong immune responses in the vaccinated mice, which specifically reacted with HA1 proteins and an inactivated heterologous H5N1 virus. Both proteins were able to cross-neutralize infections by one homologous strain (clade 2.3) and four heterologous strains belonging to clades 0, 1, and 2.2 of H5N1 pseudoviruses as well as three heterologous strains (clades 0, 1, and 2.3.4) of H5N1 live virus. Importantly, immunization with these two vaccine candidates, especially HA1-Fdc, provided complete cross-clade protection against high-dose lethal challenge of different strains of H5N1 virus covering clade 0, 1, and 2.3.4 in the tested mouse model. This study suggests that the recombinant fusion proteins, particularly HA1-Fdc, could be developed into an efficacious universal H5N1 influenza vaccine, providing cross-protection against infections by divergent strains of highly pathogenic H5N1 virus.

negative: A considerable proportion of individuals with asymptomatic SARS-CoV-2 infection in Tibetan population Severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) quickly became a major epidemic threat in the whole China. We analysed SARS-Cov-2 infected cases from Tibetan Autonomous Prefecture, and noted divergent characteristics of these Tibetans infected cases compared to Han Chinese, characterizing by a considerable proportion of asymptomatic carriers (21.7%), and few symptomatic patients with initial symptom of fever (7.7%). Here, we did a descriptive study on clinical characteristics of 18 asymptomatic individuals with SARS-CoV-2 infection. The median age of these asymptomatic carriers was 31 years and one third of them were students, aged under 20 years. Notably, some of asymptomatic carriers had recognizable changes in radiological and laboratory indexes. Our finding indicates a potentially big number of SARS-CoV-2 asymptomatic carriers in prevalent area, highlighting a necessity of screening individuals with close contact of infected patients, for a better control on the spread of SARS-CoV-2 infection.

negative: In-silico nucleotide and protein analyses of S-gene region in selected zoonotic coronaviruses reveal conserved domains and evolutionary emergence with trajectory course of viral entry from SARS-CoV2 genomic data The recent zoonotic coronavirus virus outbreak of a novel type [COVID 19] has necessitated the adequate understanding of the evolutionary pathway of zoonotic viruses which adversely affects human populations for therapeutic constructs to combat the pandemic now and in the future. We analyzed conserved domains of the severe acute respiratory coronavirus 2 [SARS-CoV2] for possible targets of viral entry inhibition in host cells, evolutionary relationship of human coronavirus [229E] and zoonotic coronaviruses with SAR-CoV2 as well as evolutionary relationship between selected SARS-CoV 2 genomic data. Conserved domains with antagonistic action on host innate antiviral cellular mechanisms in SARS-CoV 2 include nsp 11, nsp 13 etc. Also, multiple sequence alignments of the spike [S] gene protein of selected candidate zoonotic coronaviruses alongside the S gene protein of the SARs-CoV2 revealed closest evolutionary relationship [95.6%] with pangolin coronaviruses [S] gene. Clades formed between Wuhan SARS-CoV2 phylogeny data and five others suggests viral entry trajectory while revealing genomic and protein SARS CoV 2 data from Philippines as early ancestors. Therefore, phylogeny of SARS-CoV 2 genomic data suggests profiling in diverse populations with and without the outbreak alongside migration history and racial background for mutation tracking and dating of viral subtype divergence which is essential for effective management of present and future zoonotic coronavirus outbreaks.

negative: Induction of mucosal immune responses and protection against enteric viruses: rotavirus infection of gnotobiotic pigs as a model Abstract Enteric viruses are a major cause of diarrhea in animals and humans. Among them, rotaviruses are one of the most important causes of diarrhea in young animals and human infants. A lack of understanding of mechanisms to induce intestinal immunity and the correlates of protective immunity in neonates has impaired development of safe and effective vaccines against enteric viruses. Studies of candidate vaccines using an adult mouse model of subclinical enteric viral infections often do not predict vaccine efficacy against disease evaluated in neonatal large animals. A series of studies have been conducted using a neonatal gnotobiotic pig model of rotavirus infection and diarrhea to identify correlates of protective immunity and to evaluate traditional and novel vaccine approaches for the induction of mucosal immune responses and protection to enteric viruses. Gnotobiotic pigs recovered from infection with virulent Wa human rotavirus (HRV) (mimic natural infection) had high numbers of intestinal IgA rotavirus-specific primary antibody-secreting cells (ASCs) and memory B-cells (to recall antigen) measured by ELISPOT assay, which correlated with complete protection against rotavirus challenge. Most short-term IgA memory B-cells were resident in the ileum, the major site of rotavirus replication. Spleen, not the bone marrow, was the major resident site for longer-term IgG memory B-cells. Candidate rotavirus vaccines evaluated in pigs for their ability to induce intestinal or systemic ASC and protection against rotavirus infection and diarrhea included attenuated live virus, inactivated virus, and baculovirus-expressed double-layered rotavirus-like particles (2/6-VLPs). In combination with those candidate vaccines, various adjuvants, delivery systems, and immunization routes were tested, including incomplete Freund’s adjuvant for i.m. immunization, and a mutant Escherichia coli heat labile enterotoxin R192G (mLT) for i.n. immunization. It was shown that orally administered replicating vaccines were most effective for priming for intestinal IgA ASC and memory B-cell responses, but i.n. administered non-replicating 2/6-VLPs plus mLT were effective as booster vaccines. We conclude that protective immunity depends on the magnitude, location, viral protein-specificity, and isotype of the antibody responses induced by vaccination. Therefore highly effective enteric viral vaccines should: (i) induce sufficient levels of intestinal IgA antibodies; (ii) include viral antigens that induce neutralizing antibodies; and (iii) require the use of effective mucosal adjuvants or antigen delivery systems for non-replicating oral or i.n. vaccines.

negative: COVID-19 from veterinary medicine and one health perspectives: What animal coronaviruses have taught us

negative: Severe Acute Respiratory Syndrome – a New Coronavirus from the Chinese Dragon's Lair The recent identification of a novel clinical entity, the severe acute respiratory syndrome (SARS), the rapid subsequent spread and case fatality rates of 14–15% have prompted a massive international collaborative investigation facilitated by a network of laboratories established by the World Health Organization (WHO). As SARS has the potential of becoming the first pandemic of the new millennium, a global warning by the WHO was issued on 12 March 2003. The disease, which is believed to have its origin in the Chinese Guangdong province, spread from Hong Kong via international airports to its current worldwide distribution. The concerted efforts of a globally united scientific community have led to the independent isolation and identification of a novel coronavirus from SARS patients by several groups. The extraordinarily rapid isolation of a causative agent of this newly emerged infectious disease constitutes an unprecedented scientific achievement. The main scope of the article is to provide the clinician with an overview of the natural history, epidemiology and clinical characteristics of SARS. On the basis of the recently published viral genome and structural features common to the members of the coronavirus family, a model for host cell–virus interaction and possible targets for antiviral drugs are presented. The epidemiological consequences of introducing a novel pathogen in a previously unexposed population and the origin and evolution of a new and more pathogenic strain of coronavirus are discussed.

negative: COVID-19: the gendered impacts of the outbreak

negative: Safety of foods, food supply chain and environment within the COVID-19 pandemic BACKGROUND: The COVID-19 pandemic has generated a new era in the world while we still figure out the consequences in different aspects of our daily life. The food supply chain and the food industry do not comprise an exception. SCOPE AND APPROACH: This review summarizes the possible transmission ways of COVID-19 through the foods, food supply chain, surfaces, and environment before exploring the development of corresponding detection tools of SARS-CoV-2. For the time being, the possibility of transmission through the food sector is considered negligible, and tracing of SARS-CoV-2 in working environments is not considered as a priority by public authorities. However, the adverse effects on the environment, food systems, and people along the food supply chain are already evident. KEY FINDINGS AND CONCLUSIONS: As long as we move from farm to fork, more safety measures are needed since more people (and subsequently more potential sources of infection) are involved in the process. The need for developing respective bioanalytical protocols for food and environmental safety applications to adapt in the post-lockdown period is also highlighted.

negative: Oral typhoid vaccine Ty21a elicits antigen-specific resident memory CD4(+) T cells in the human terminal ileum lamina propria and epithelial compartments BACKGROUND: Salmonella enterica serovar Typhi (S. Typhi) is a highly invasive bacterium that infects the human intestinal mucosa and causes ~ 11.9–20.6 million infections and ~ 130,000–223,000 deaths annually worldwide. Oral typhoid vaccine Ty21a confers a moderate level of long-lived protection (5–7 years) in the field. New and improved vaccines against enteric pathogens are needed but their development is hindered by a lack of the immunological correlates of protection especially at the site of infection. Tissue resident memory T (T(RM)) cells provide immediate adaptive effector immune responsiveness at the infection site. However, the mechanism(s) by which S. Typhi induces T(RM) in the intestinal mucosa are unknown. Here, we focus on the induction of S. Typhi-specific CD4+T(RM) subsets by Ty21a in the human terminal ileum lamina propria and epithelial compartments. METHODS: Terminal ileum biopsies were obtained from consenting volunteers undergoing routine colonoscopy who were either immunized orally with 4 doses of Ty21a or not. Isolated lamina propria mononuclear cells (LPMC) and intraepithelial lymphocytes (IEL) CD4+T(RM) immune responses were determined using either S. Typhi-infected or non-infected autologous EBV-B cell lines as stimulator cells. T-CMI was assessed by the production of 4 cytokines [interferon (IFN)γ, interleukin (IL)-2, IL-17A and tumor necrosis factor (TNF)α] in 36 volunteers (18 vaccinees and 18 controls volunteers). RESULTS: Although the frequencies of LPMC CD103+ CD4+T(RM) were significant decreased, both CD103+ and CD103− CD4+T(RM) subsets spontaneously produced significantly higher levels of cytokines (IFNγ and IL-17A) following Ty21a-immunization. Importantly, we observed significant increases in S. Typhi-specific LPMC CD103+ CD4+T(RM) (IFNγ and IL-17A) and CD103− CD4+T(RM) (IL-2 and IL-17A) responses following Ty21a-immunization. Further, differences in S. Typhi-specific responses between these two CD4+T(RM) subsets were observed following multifunctional analysis. In addition, we determined the effect of Ty21a-immunization on IEL and observed significant changes in the frequencies of IEL CD103+ (decrease) and CD103− CD4+T(RM) (increase) following immunization. Finally, we observed that IEL CD103− CD4+T(RM), but not CD103+ CD4+T(RM), produced increased cytokines (IFNγ, TNFα and IL-17A) to S. Typhi-specific stimulation following Ty21a-immunization. CONCLUSIONS: Oral Ty21a-immunization elicits distinct compartment specific immune responses in CD4+T(RM) (CD103+ and CD103−) subsets. This study provides novel insights in the generation of local vaccine-specific responses. Trial registration This study was approved by the Institutional Review Board and registered on ClinicalTrials.gov (identifier NCT03970304, Registered 29 May 2019—Retrospectively registered, http://www.ClinicalTrials.gov/NCT03970304)

negative: Chapter 15 Biology and Diseases of Ruminants (Sheep, Goats, and Cattle) Ruminants continue to be important in their traditional role in agricultural research and teaching. They are now also extensively used for studies in molecular biology; genetic engineering; and biotechnology for basic science, agricultural and clinical applications. Concern and interest for the welfare for these species and improved understanding of their biology and behavior have continued and are reflected in changing husbandry and management systems. This chapter addresses at high levels basic biology, husbandry, and the more common or important diseases of the three ruminant species used most commonly in the laboratory, namely sheep, goats and cattle.

negative: COVID-19 - Considerations for the paediatric rheumatologist The novel coronavirus SARS-CoV2 is a threat to the health and well-being of millions of lifes across the globe. A significant proportion of adult patients require hospitalisation and may develop severe life-threatening complications. Children, on the other hand, can carry and transmit the virus, but usually do not develop severe disease. Mortality in the paediatric age-group is relatively low. Differences in virus containment and clearance, as well as reduced inflammation-related tissue and organ damage may be caused by age-specific environmental and host factors. Since severe complications in adults are frequently caused by uncontrolled immune responses and a resulting "cytokine storm" that may be controlled by targeted blockade of cytokines, previously established treatment with immunosuppressive treatments may indeed protect children from complications.

negative: Coronaviridae, pathogenetic and clinical aspects: An update Abstract A review is given about pathogenetic and clinical aspects of the well-known as well as of recently detected members of the family Coronaviridae. Special attention is paid to coronavirus infections of domestic cattle and pets, whereas avian, murine, rat and human coronaviruses are summarized briefly.

negative: A prime-boost vaccination protocol optimizes immune responses against the nucleocapsid protein of the SARS coronavirus Severe acute respiratory syndrome (SARS) is a serious infectious disease caused by the SARS coronavirus. We assessed the potential of prime-boost vaccination protocols based on the nucleocapsid (NC) protein co-administered with a derivative of the mucosal adjuvant MALP-2 or expressed by modified Vaccinia virus Ankara (MVA–NC) to stimulate humoral and cellular immune responses at systemic and mucosal levels. The obtained results demonstrated that strong immune responses can be elicited both at systemic and mucosal levels following a heterologous prime-boost vaccination protocol consisting in priming with NC protein add-mixed with MALP-2 by intranasal route and boosting with MVA–NC by intramuscular route.

negative: Age-dependent immune responses and immune protection after avian coronavirus vaccination Abstract Infectious bronchitis virus (IBV) is an endemic disease of chickens and a major contributor to economic losses for the poultry industry despite vaccination. Recent observations indicated that chicks may have an immature immune system immediately after hatching when vaccinated for IBV. Therefore we hypothesized that early IBV vaccination will generate an immature, poorly protective IBV-specific immune response contributing to immune escape and persistence of IBV. To test this hypothesis the IBV-specific immune response and immune protection were measured in chicks vaccinated at different ages. This demonstrated a delayed production of IgG and IgA plasma antibodies in the 1, 7 and 14-day-old vaccination groups and also lower IgA antibody levels were observed in plasma of the 1-day-old group. Similar observations were made for antibodies in tears. In addition, IgG antibodies from the 1-day-old group had lower avidity indices than day 28 vaccinated birds. The delayed and/or lower antibody response combined with lower IgG avidity indices coincided with increased tracheal inflammation and depletion of tracheal epithelia cells and goblet cells upon IBV field strain challenge. The lack of vaccine-mediated protection was most pronounced in the 1-day-old vaccination group and to a lesser extent the 7-day-old group, while the 14-day-old and older chickens were protected. These data strongly support IBV vaccination after day 7 post hatch.

negative: SARS-CoV2 entry and spread in the lymphatic drainage system of the brain

negative: Severe acute respiratory syndrome, a pathological immune response to the new coronavirus--implications for understanding of pathogenesis, therapy, design of vaccines, and epidemiology. Findings coming from autopsies and serum of SARS patients suggest an important immune-inflammatory implication in the evolution to respiratory distress. Conditions such as HIV infection or treatment with immunosuppressors (in cancer or autoimmune diseases) are not among the bad prognosis factors for development of distress. To date, there have been no reported case fatalities in children, probably due to their more immature immune system. Our conclusions follow: (1) The milder form of SARS in children and the apparent protective factor that immunosupression represent rules out a significant viral cytopathic effect (they would be the most affected). (2) The evidence for immune implication in distress strongly supports immunomodulators for therapy: phosphodiesterase inhibitors (due to their down-modulating activity on proinflammatory cytokines); inhaled corticoids (aimed at producing a local immunomodulation); teophylline or nedocromil sodium (which prevents inflammatory cell recruitment into the airway wall). (3) An early immunomodulatory therapy, based on the levels of proinflammatory cytokines and clinical parameters to evaluate the respiratory function such as arterial oxygen saturation, could prevent the occurrence of distress. (4) Vaccine design should consider the immune origin of distress. (5) Physicians should be aware of mildly symptomatic patients (children, immuno-compromised hosts) to avoid transmission to immunocompetent adults.

negative: Traditional Chinese Medicine in the Treatment of Patients Infected with 2019-New Coronavirus (SARS-CoV-2): A Review and Perspective Currently, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2, formerly known as 2019-nCoV, the causative pathogen of Coronavirus Disease 2019 (COVID-19)) has rapidly spread across China and around the world, causing an outbreak of acute infectious pneumonia. No specific anti-virus drugs or vaccines are available for the treatment of this sudden and lethal disease. The supportive care and non-specific treatment to ameliorate the symptoms of the patient are the only options currently. At the top of these conventional therapies, greater than 85% of SARS-CoV-2 infected patients in China are receiving Traditional Chinese Medicine (TCM) treatment. In this article, relevant published literatures are thoroughly reviewed and current applications of TCM in the treatment of COVID-19 patients are analyzed. Due to the homology in epidemiology, genomics, and pathogenesis of the SARS-CoV-2 and SARS-CoV, and the widely use of TCM in the treatment of SARS-CoV, the clinical evidence showing the beneficial effect of TCM in the treatment of patients with SARS coronaviral infections are discussed. Current experiment studies that provide an insight into the mechanism underlying the therapeutic effect of TCM, and those studies identified novel naturally occurring compounds with anti-coronaviral activity are also introduced.

negative: Estimating SARS-CoV-2 seroprevalence and epidemiological parameters with uncertainty from serological surveys Establishing how many people have already been infected by SARS-CoV-2 is an urgent priority for controlling the COVID-19 pandemic. Patchy virological testing has hampered interpretation of confirmed case counts, and unknown rates of asymptomatic and mild infections make it challenging to develop evidence-based public health policies. Serological tests that identify past infection can be used to estimate cumulative incidence, but the relative accuracy and robustness of various sampling strategies has been unclear. Here, we used a flexible framework that integrates uncertainty from test characteristics, sample size, and heterogeneity in seroprevalence across tested subpopulations to compare estimates from sampling schemes. Using the same framework and making the assumption that serological positivity indicates immune protection, we propagated these estimates and uncertainty through dynamical models to assess the uncertainty in the epidemiological parameters needed to evaluate public health interventions. We examined the relative accuracy of convenience samples versus structured surveys to estimate population seroprevalence, and found that sampling schemes informed by demographics and contact networks outperform uniform sampling. The framework can be adapted to optimize the design of serological surveys given particular test characteristics and capacity, population demography, sampling strategy, and modeling approach, and can be tailored to support decision-making around introducing or removing interventions.

negative: Childhood severe acute respiratory syndrome, coronavirus infections and asthma Severe acute respiratory syndrome (SARS) is a new infectious disease caused by a novel coronavirus. Children appear to be less susceptible to the SARS coronavirus, although the other non‐SARS coronaviruses can cause respiratory infections in adults and in children of all ages. The exact reasons as to why SARS preferentially affects adults, and not children, are still unknown. Many hypotheses exist and need to be explored. During the outbreak of SARS, there did not appear to be an increase in asthma exacerbations in children.

negative: The outbreak of COVID-19: An overview In late December 2019, a previous unidentified coronavirus, currently named as the 2019 novel coronavirus#, emerged from Wuhan, China, and resulted in a formidable outbreak in many cities in China and expanded globally, including Thailand, Republic of Korea, Japan, United States, Philippines, Viet Nam, and our country (as of 2/6/2020 at least 25 countries). The disease is officially named as Coronavirus Disease-2019 (COVID-19, by WHO on February 11, 2020). It is also named as Severe Pneumonia with Novel Pathogens on January 15, 2019 by the Taiwan CDC, the Ministry of Health and is a notifiable communicable disease of the fifth category. COVID-19 is a potential zoonotic disease with low to moderate (estimated 2%–5%) mortality rate. Person-to-person transmission may occur through droplet or contact transmission and if there is a lack of stringent infection control or if no proper personal protective equipment available, it may jeopardize the first-line healthcare workers. Currently, there is no definite treatment for COVID-19 although some drugs are under investigation. To promptly identify patients and prevent further spreading, physicians should be aware of the travel or contact history of the patient with compatible symptoms.

negative: The role of asymptomatic SARS-CoV-2 infections: rapid living systematic review and meta-analysis Background: There is substantial disagreement about the level of asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in a population. The disagreement results, in part, from the interpretation of studies that report a proportion of asymptomatic people with SARS-CoV-2 detected at a single point. Review questions: 1. Amongst people who become infected with SARS-CoV-2, what proportion does not experience symptoms at all during their infection? 2. Amongst people with SARS-CoV-2 infection who are asymptomatic when diagnosed, what proportion will develop symptoms later? 3. What proportion of SARS-CoV-2 transmission is accounted for by people who are either asymptomatic throughout infection, or pre-symptomatic? Methods: Rapid living systematic review (protocol https://osf.io/9ewys/). We searched Pubmed, Embase, bioRxiv and medRxiv using a living evidence database of SARS-CoV-2 literature on 25.03.2020. We included studies of people with SARS-CoV-2 diagnosed by reverse transcriptase PCR (RT-PCR) that documented follow-up and symptom status at the beginning and end of follow-up and modelling studies. Study selection, data extraction and bias assessment were done by one reviewer and verified by a second, with disagreement resolved by discussion or a third reviewer. We used a common-effect model to synthesise proportions from comparable studies. Results: We screened 89 studies and included 11. We estimated an upper bound for the proportion of asymptomatic SARS-CoV-2 infections of 29% (95% confidence interval 23 to 37%) in eight studies. Selection bias and likely publication bias affected the family case investigation studies. One statistical modelling study estimated the true proportion of asymptomatic infections at 18% (95% credibility interval 16 to 20%). Estimates of the proportions of pre-symptomatic individual in four studies were too heterogeneous to combine. In modelling studies, 40-60% of all SARS-CoV-2 infections are the result of transmission from pre-symptomatic individuals, with a smaller contribution from asymptomatic individuals. Conclusions: An intermediate contribution of pre-symptomatic and asymptomatic infections to overall SARS-CoV-2 transmission means that combination prevention, with enhanced hand and respiratory hygiene, testing tracing and isolation strategies and social distancing, will continue to be needed. The findings of this systematic review of publications early in the pandemic suggests that most SARS-CoV-2 infections are not asymptomatic throughout the course of infection.

negative: Estimation of protection for COVID-19 in children from epidemiological information and estimate effect of policy in Japan Background: Incidence in children was much less than in adults during the COVID−19 outbreak. Sports and entertainment events were canceled (VEC) in Japan for two weeks during 26 February − 13 March. Most schools were closed (SC). Object: We construct a susceptible−infected −recovered model using three age classes and estimate the basic reproduction number (R0) and protection level among children simultaneously. Then we simulate SC and VEC effects. Method: We used data of patients with symptoms in Japan during 14 January to assess SC and VEC introduction. Effects of SC and VEC were incorporated into the model through change in the contact pattern or frequencies among age classes. Results: Results suggest R0 as 2.86 [95%CI of 2.73, 2.97]. The protection level was estimated as 0.4 [0.2, 0.7]. SC and VEC can reduce the total number of patients significantly, by 6−7%. Discussion and Conclusion: The estimated R0 was similar to that found from other studies in China and Japan. We found a significant protection level among children, and by effects of SC and VEC. Introduction

negative: Predicting the receptor-binding domain usage of the coronavirus based on kmer frequency on spike protein

negative: The Threat from Viruses Infectious disease represent the most significant threat to human health. Significant geologic cataclysmic events have caused the extinction of countless species, but these “Wrath of God” events predate the emergence of Homo sapiens. Pandemic infections have accompanied the rise of human civilization frequently re-occurring leaving a lasting imprint on human history punctuated by profound loss of life. Emerging infections become endemic and are here to stay marking their presence with an annual death toll. Each decade brings a new onslaught of emerging infectious agents. We are surprised again and again but are never prepared. The long-term consequences often remain unrecognized and are always inconvenient including cancer, cardiovascular disease and immune associated diseases that threaten our health. Reliance on clusters of clinical symptoms in the face of diverse and non-descriptive viral infection symptoms is a foolhardy form of crisis management. Viral success is based on rapid replication resulting in large numbers. Single-stranded RNA viruses with their high replication error rate represent a paradigm for resilience.

negative: Awareness of MERS-CoV among Staff Members of Prince Sultan Military Medical City in Riyadh, Saudi Arabia Background The Middle East respiratory syndrome coronavirus (MERS-CoV) developed infections that caused serious epidemics. Special priority of awareness and prompt initiative involvement of health workers (HW) during such intensified health situation necessitated an assessment of their preparedness, appropriate attitudes and protective strategies for better efficiency modes and acceleration during emergency. Methods HW of Prince Sultan Military Medical city in Riyadh, Saudi Arabia were reviewed through specifically designed questionnaires to acquire the demanded data. It included clinical and demographic information about the viral diseases, associated signs and symptoms, transmission and protection, and attitudes about the MERS-CoV disease. Results The study was accomplished between August and November, 2017 and 477 participants of the medical city, successfully completed the study questionnaire (Appendix I). Females represented a majority and there was an indirectly proportional decrease with the increasing age. Gradual educational increase levels reflected dominance of the university degree holders. Jobs were dominated by nurses and non-Saudis were a majority whilst, the highly experienced, (>10 years) were a minority. A majority recognized the viral transmission methods, popular information sources of MERS-CoV and associated medical terms. Highest scores were observed in dealing with protective aids and recognizing symptoms of disease. High adherence to hand hygiene protocols and correct washing steps were recorded. Correct and high levels were observed in taking preventive measures and avoiding infection. Participants responded correctly to negative and wrong actions that patients should refrain from. High scores were observed in taking appreciable attitudes towards oneself and towards others. Conclusions Expatriates were majority and nurses were dominant which, necessitates Saudization of this sector. Ministry of health pamphlets and seminars were of less impact in invigilating HW, hence, more attention and efforts are demanded. HW were quite aware of the basic and emergent health policies during epidemic episodes of MERS-CoV.

negative: Immunity‐targeted approaches to the management of chronic and recurrent upper respiratory tract disorders in children BACKGROUND: Upper respiratory tract infections (URTIs), including rhinitis, nasopharyngitis, tonsillitis and otitis media (OM), comprise of 88% of total respiratory infections, especially in children. Therefore effective prevention and treatment of RTIs remain a high priority worldwide. Preclinical and clinical data highlight the rationale for the use and effectiveness of immunity‐targeted approaches, including targeted immunisations and non‐specific immunomodulation in the prevention and management of recurrent upper RTIs. OBJECTIVE OF REVIEW: The idea of this review was to summarise the current evidence and address key questions concerning the use of conservative and immunity‐targeted approaches to recurrent and chronic URTIs, with a focus on the paediatric population. SEARCH STRATEGY/EVALUATION METHOD: Literature searches were conducted in March 2017 and updated in September 2017 using: Academic Search Complete; CENTRAL; Health Source: Nursing/Academic Edition; MEDLINE; clinicaltrials.gov; and Cochrane databases. In total, 84 articles were retrieved and reviewed. Two independent researchers focused on primary and secondary endpoints in systematic reviews, meta‐analyses and randomised, controlled trials, using immunity‐directed strategies as the control group or within a subpopulation of larger studies. Existing guidelines and interventional/observational studies on novel applications were also included. RESULTS: Children are particularly susceptible to RTIs due to the relative immaturity of their immune systems, as well as other potential predisposing factors such as day care attendance and/or toxic environmental factors (eg increased pathogenic microbial exposure and air pollutants). Recurrent URTIs can affect otherwise healthy children, leading to clinical sequelae and complications, including the development of chronic conditions or the need for surgery. Available pre‐clinical and clinical data highlight the rationale for the use and effectiveness of immunity‐targeted approaches, including targeted immunisations (flu and pneumococcal vaccines) and non‐specific immunomodulation (bacterial lysates), in the prevention and management of recurrent croup, tonsillitis, otitis media, recurrent acute rhinosinusitis and chronic rhinosinusitis. CONCLUSIONS: In this review, we summarise the current evidence and provide data demonstrating that some immunity‐targeted strategies, including vaccination and immunomodulation, have proved effective in the treatment and prevention of recurrent and chronic URTIs in children.

negative: Duration of immunity in dogs after vaccination or naturally acquired infection. This paper reviews current scientific information about the duration of immunity induced in dogs by infection or vaccination. It describes the shortcomings of the methods used to measure the immune responses of dogs, and explains the need for basic studies on the nature of protective humoral and cellular responses, and standardised assays for the long-term duration of immunity to pathogens other than rabies. The information is inadequate to warrant uniform recommendations on the ideal intervals for vaccination; each vaccine must be evaluated on the basis of its own merits and the characteristics of the disease it is intended to guard against.

negative: Association of Seropositivity for Influenza and Coronaviruses with History of Mood Disorders and Suicide Attempts BACKGROUND: Anecdotal reports of mood disorder following infection with common respiratory viruses with neurotropic potential have been in existence since the last century. Nevertheless, systematic studies on the association between these viruses and mood disorders are lacking. METHODS: Influenza A, B and coronavirus antibody titers were measured in 257 subjects with recurrent unipolar and bipolar disorder and healthy controls, by SCID. Pearson’s χ(2) tests and logistic regression models were used to analyze associations between seropositivity for coronaviruses, influenza A and B viruses and the following: a) history of recurrent mood disorders b) having attempted suicide in the past c) uni- vs. bi-polarity and d) presence of psychotic features during mood episodes. RESULTS: Seropositivity for influenza A (p=0.004), B (p<0.0001) and coronaviruses (p<0.0001) were associated with history of mood disorders but not with the specific diagnosis of unipolar or bipolar depression. Seropositivity for influenza B was significantly associated with a history of suicide attempt (p =0.001) and history of psychotic features (p =0.005). LIMITATIONS: The design was cross-sectional Socioeconomic factors, inflammatory markers, and axis II psychopathology were not assessed. CONCLUSIONS: The association of seropositivity for influenza and coronaviruses with a history of mood disorders, and influenza B with suicidal behavior require replication in larger longitudinal samples. The need for these studies is additionally supported by the high incidence of these viral infections, the high prevalence of mood disorders, and resilience of suicide epidemics.

negative: Induction of protective immunity against transmissible gastroenteritis virus after exposure of neonatal pigs to porcine respiratory coronavirus. OBJECTIVE To test the ability of porcine respiratory coronavirus (PRCV) to induce protective immunity to antigenically related transmissible gastroenteritis virus (TGEV) in neonatal pigs. DESIGN Neonatal pigs were exposed to PRCV when they were 2, 4, or 6 days old and challenge-exposed to virulent TGEV at 10 days of age. ANIMALS 34 hysterectomy-derived, colostrum-deprived pigs. PROCEDURE After challenge exposure, clinical signs were observed, body weight, antibody response, and virus shedding were measured, and mortality was determined. RESULTS After exposure to PRCV, principals had a slightly slower rate of weight gain than did controls; with 1 exception (a PRCV-exposed pig that was dyspneic for 1 day), principals and controls remained clinically normal until shortly after challenge exposure, when all pigs became listless and anorectic and developed watery diarrhea. However, by day 3, most of the pigs that had been exposed to PRCV when they were either 2 or 4 days old began to recover and most (15/18) survived. Conversely, the clinical condition of most of the other pigs worsened and most (14/16) died. Pigs exposed to PRCV when they were 2 or 4 days old also differed from all other pigs in that they had serum virus-neutralizing antibodies for PRCV and TGEV at the time of challenge exposure. CONCLUSIONS The PRCV can induce protective immunity to TGEV in neonatal pigs and such immunity develops at or about 6 days after exposure to PRCV. Moreover, protective immunity may be coincident with the appearance of virus-neutralizing antibody. CLINICAL RELEVANCE Exposure to PRCV should enhance a TGE herd vaccination program.

negative: Pathology and Pathogenesis of Severe Acute Respiratory Syndrome Severe acute respiratory syndrome (SARS) is an emerging infectious viral disease characterized by severe clinical manifestations of the lower respiratory tract. The pathogenesis of SARS is highly complex, with multiple factors leading to severe injury in the lungs and dissemination of the virus to several other organs. The SARS coronavirus targets the epithelial cells of the respiratory tract, resulting in diffuse alveolar damage. Several organs/cell types may be infected in the course of the illness, including mucosal cells of the intestines, tubular epithelial cells of the kidneys, neurons of the brain, and several types of immune cells, and certain organs may suffer from indirect injury. Extensive studies have provided a basic understanding of the pathogenesis of this disease. In this review we describe the most significant pathological features of SARS, explore the etiological factors causing these pathological changes, and discuss the major pathogenetic mechanisms. The latter include dysregulation of cytokines/chemokines, deficiencies in the innate immune response, direct infection of immune cells, direct viral cytopathic effects, down-regulation of lung protective angiotensin converting enzyme 2, autoimmunity, and genetic factors. It seems that both abnormal immune responses and injury to immune cells may be key factors in the pathogenesis of this new disease.

negative: The risk of SARS-CoV-2 transmission to pets and other wild and domestic animals strongly mandates a one-health strategy to control the COVID-19 pandemic

negative: Otorhinolaryngologists and Coronavirus Disease 2019 (COVID-19)

negative: Mapping of antigenic sites on the nucleocapsid protein of the severe acute respiratory syndrome coronavirus. Antigenic sites on the nucleocapsid (N) protein of severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV) were mapped by Pepscan analysis with overlapping peptides that span the N protein sequence. Two major immunodominant epitopes located in the C-terminal region (amino acids [aa] 362 to 412) and middle region (aa 153 to 178) reacted with more than 75% of sera from SARS patients. Several minor immunodominant epitopes were reactive with about 50% of the SARS sera. Antisera from mice immunized with inactivated SARS-CoV recognized the two major immunodominant epitopes and one antigenic site located adjacent to the N-terminal region (aa 76 to 101), which did not react with the sera from SARS patients. Several monoclonal antibodies against SARS-CoV bound to the N- or C-terminal antigenic sites. These results suggest that the above antigenic sites on the N protein are important in eliciting humoral immune response against SARS-CoV in humans and animals and can be used as antigens for developing diagnostic tests.

negative: Resumption of activity in gastroenterology departments. Recommendations by SEPD, AEEH, GETECCU and AEG Abstract The set of measures proposed by SEPD, AEEH, GETECCU and AEG are aimed to help departments in their resumption of usual activity. We have prepared a number of practical recommendations regarding patient management and the stepwise resumption of healthcare activity. These recommendations are based on the sparse, changing evidence available, and will be updated in the future according to daily needs and the availability of expendable materials to suit them; in each department they will be implemented depending upon the cumulative incidence of SARS-CoV-2 infection in each region, and the burden the pandemic has represented for each hospital. The general objectives of these recommendations include: • To protect our patients against the risks of infection with SARS-CoV-2 and to provide them with high-quality care. • To protect all healthcare professionals against the risks of infection with SARS-CoV-2. • To resume normal functioning of our departments in a setting of ongoing risk for infection with SARS-CoV-2.

negative: The preventive strategies of community hospital in the battle of fighting pandemic COVID-19 in Taiwan

negative: YouTube as a source of information on COVID-19: a pandemic of misinformation? INTRODUCTION: The COVID-19 pandemic is this century’s largest public health emergency and its successful management relies on the effective dissemination of factual information. As a social media platform with billions of daily views, YouTube has tremendous potential to both support and hinder public health efforts. However, the usefulness and accuracy of most viewed YouTube videos on COVID-19 have not been investigated. METHODS: A YouTube search was performed on 21 March 2020 using keywords ‘coronavirus’ and ‘COVID-19’, and the top 75 viewed videos from each search were analysed. Videos that were duplicates, non-English, non-audio and non-visual, exceeding 1 hour in duration, live and unrelated to COVID-19 were excluded. Two reviewers coded the source, content and characteristics of included videos. The primary outcome was usability and reliability of videos, analysed using the novel COVID-19 Specific Score (CSS), modified DISCERN (mDISCERN) and modified JAMA (mJAMA) scores. RESULTS: Of 150 videos screened, 69 (46%) were included, totalling 257 804 146 views. Nineteen (27.5%) videos contained non-factual information, totalling 62 042 609 views. Government and professional videos contained only factual information and had higher CSS than consumer videos (mean difference (MD) 2.21, 95% CI 0.10 to 4.32, p=0.037); mDISCERN scores than consumer videos (MD 2.46, 95% CI 0.50 to 4.42, p=0.008), internet news videos (MD 2.20, 95% CI 0.19 to 4.21, p=0.027) and entertainment news videos (MD 2.57, 95% CI 0.66 to 4.49, p=0.004); and mJAMA scores than entertainment news videos (MD 1.21, 95% CI 0.07 to 2.36, p=0.033) and consumer videos (MD 1.27, 95% CI 0.10 to 2.44, p=0.028). However, they only accounted for 11% of videos and 10% of views. CONCLUSION: Over one-quarter of the most viewed YouTube videos on COVID-19 contained misleading information, reaching millions of viewers worldwide. As the current COVID-19 pandemic worsens, public health agencies must better use YouTube to deliver timely and accurate information and to minimise the spread of misinformation. This may play a significant role in successfully managing the COVID-19 pandemic.

negative: Comparison of risk factors for viral and nonviral asthma exacerbations

negative: Chapter Five Modified Vaccinia Virus Ankara History, Value in Basic Research, and Current Perspectives for Vaccine Development Abstract Safety tested Modified Vaccinia virus Ankara (MVA) is licensed as third-generation vaccine against smallpox and serves as a potent vector system for development of new candidate vaccines against infectious diseases and cancer. Historically, MVA was developed by serial tissue culture passage in primary chicken cells of vaccinia virus strain Ankara, and clinically used to avoid the undesirable side effects of conventional smallpox vaccination. Adapted to growth in avian cells MVA lost the ability to replicate in mammalian hosts and lacks many of the genes orthopoxviruses use to conquer their host (cell) environment. As a biologically well-characterized mutant virus, MVA facilitates fundamental research to elucidate the functions of poxvirus host-interaction factors. As extremely safe viral vectors MVA vaccines have been found immunogenic and protective in various preclinical infection models. Multiple recombinant MVA currently undergo clinical testing for vaccination against human immunodeficiency viruses, Mycobacterium tuberculosis or Plasmodium falciparum. The versatility of the MVA vector vaccine platform is readily demonstrated by the swift development of experimental vaccines for immunization against emerging infections such as the Middle East Respiratory Syndrome. Recent advances include promising results from the clinical testing of recombinant MVA-producing antigens of highly pathogenic avian influenza virus H5N1 or Ebola virus. This review summarizes our current knowledge about MVA as a unique strain of vaccinia virus, and discusses the prospects of exploiting this virus as research tool in poxvirus biology or as safe viral vector vaccine to challenge existing and future bottlenecks in vaccinology.

negative: Saudi Arabia`s measures to curb the COVID-19 outbreak: temporary suspension of the Umrah pilgrimage

negative: Difference of coagulation features between severe pneumonia induced by SARS-CoV2 and non-SARS-CoV2 Severe coronavirus disease 2019 (COVID-19) is commonly complicated with coagulopathy, the difference of coagulation features between severe pneumonia induced by SARS-CoV2 and non-SARS-CoV2 has not been analyzed. Coagulation results and clinical features of consecutive patients with severe pneumonia induced by SARS-CoV2 (COVID group) and non-SARS-CoV2 (non-COVID group) in Tongji hospital were retrospectively analyzed and compared. Whether patients with elevated D-dimer could benefit from anticoagulant treatment was evaluated. There were 449 COVID patients and 104 non-COVID patients enrolled into the study. The 28-day mortality in COVID group was approximately twofold of mortality in non-COVID group (29.8% vs. 15.4%, P = 0.003), COVID group were older (65.1 ± 12.0 vs. 58.4 ± 18.0, years, P < 0.001) and with higher platelet count (215 ± 100 vs. 188 ± 98, ×10(9)/L, P = 0.015), comparing to non-COVID group. The 28-day mortality of heparin users were lower than nonusers In COVID group with D-dimer > 3.0 μg/mL (32.8% vs. 52.4%, P = 0.017). Patients with severe pneumonia induced by SARS-CoV2 had higher platelet count than those induced by non-SARS-CoV2, and only the former with markedly elevated D-dimer may benefit from anticoagulant treatment.

negative: Crosstalk between autophagy and inflammatory signaling pathways: balancing host defence and homeostasis Autophagy has broad functions in immunity ranging from cell autonomous defense to coordination of complex multicellular responses. The successful resolution of infection and avoidance of autoimmunity necessitates efficient and timely communication between autophagy and pathways that sense the immune environment. In this article, progress in elucidating mechanisms of crosstalk between autophagy and inflammatory signaling cascades will be reviewed. The recent literature indicates that a variety of immune mediators induce or repress autophagy. It is also becoming increasing clear that immune signaling cascades are subject to regulation by autophagy, and that a return to homeostasis following a robust immune response is critically dependent on this pathway. Importantly, examples of non-canonical forms of autophagy in mediating immunity are pervasive. Improved mechanistic understanding of the autophagy machinery offers hope for treating infectious and inflammatory diseases.

negative: Is COVID-19 receiving ADE from other coronaviruses? Abstract One of the most perplexing questions regarding the current COVID-19 coronavirus epidemic is the discrepancy between the severity of cases observed in the Hubei province of China and those occurring elsewhere in the world. One possible answer is antibody dependent enhancement (ADE) of SARS-CoV-2 due to prior exposure to other coronaviruses. ADE modulates the immune response and can elicit sustained inflammation, lymphopenia, and/or cytokine storm, one or all of which have been documented in severe cases and deaths. ADE also requires prior exposure to similar antigenic epitopes, presumably circulating in local viruses, making it a possible explanation for the observed geographic limitation of severe cases and deaths.

negative: Detection of Influenza and Other Respiratory Viruses in Air Sampled From a University Campus: A Longitudinal Study BACKGROUND: Respiratory virus–laden particles are commonly detected in the exhaled breath of symptomatic patients or in air sampled from healthcare settings. However, the temporal relationship of detecting virus-laden particles at nonhealthcare locations vs surveillance data obtained by conventional means has not been fully assessed. METHODS: From October 2016 to June 2018, air was sampled weekly from a university campus in Hong Kong. Viral genomes were detected and quantified by real-time reverse-transcription polymerase chain reaction. Logistic regression models were fitted to examine the adjusted odds ratios (aORs) of ecological and environmental factors associated with the detection of virus-laden airborne particles. RESULTS: Influenza A (16.9% [117/694]) and influenza B (4.5% [31/694]) viruses were detected at higher frequencies in air than rhinovirus (2.2% [6/270]), respiratory syncytial virus (0.4% [1/270]), or human coronaviruses (0% [0/270]). Multivariate analyses showed that increased crowdedness (aOR, 2.3 [95% confidence interval {CI}, 1.5–3.8]; P < .001) and higher indoor temperature (aOR, 1.2 [95% CI, 1.1–1.3]; P < .001) were associated with detection of influenza airborne particles, but absolute humidity was not (aOR, 0.9 [95% CI, .7–1.1]; P = .213). Higher copies of influenza viral genome were detected from airborne particles >4 μm in spring and <1 μm in autumn. Influenza A(H3N2) and influenza B viruses that caused epidemics during the study period were detected in air prior to observing increased influenza activities in the community. CONCLUSIONS: Air sampling as a surveillance tool for monitoring influenza activity at public locations may provide early detection signals on influenza viruses that circulate in the community.

negative: Characterization of antiviral T cell responses during primary and secondary challenge of laboratory cats with feline infectious peritonitis virus (FIPV) BACKGROUND: Feline infectious peritonitis (FIP) is considered highly fatal in its naturally occurring form, although up to 36% of cats resist disease after experimental infection, suggesting that cats in nature may also resist development of FIP in the face of infection with FIP virus (FIPV). Previous experimental FIPV infection studies suggested a role for cell-mediated immunity in resistance to development of FIP. This experimental FIPV infection study in specific pathogen free (SPF) kittens describes longitudinal antiviral T cell responses and clinical outcomes ranging from rapid progression, slow progression, and resistance to disease. RESULTS: Differences in disease outcome provided an opportunity to investigate the role of T cell immunity to FIP determined by T cell subset proliferation after stimulation with different viral antigens. Reduced total white blood cell (WBC), lymphocyte and T cell counts in blood were observed during primary acute infection for all experimental groups including cats that survived without clinical FIP. Antiviral T cell responses during early primary infection were also similar between cats that developed FIP and cats remaining healthy. Recovery of antiviral T cell responses during the later phase of acute infection was observed in a subset of cats that survived longer or resisted disease compared to cats showing rapid disease progression. More robust T cell responses at terminal time points were observed in lymph nodes compared to blood in cats that developed FIP. Cats that survived primary infection were challenged a second time to pathogenic FIPV and tested for antiviral T cell responses over a four week period. Nine of ten rechallenged cats did not develop FIP or T cell depletion and all cats demonstrated antiviral T cell responses at multiple time points after rechallenge. CONCLUSIONS: In summary, definitive adaptive T cell responses predictive of disease outcome were not detected during the early phase of primary FIPV infection. However emergence of antiviral T cell responses after a second exposure to FIPV, implicated cellular immunity in the control of FIPV infection and disease progression. Virus host interactions during very early stages of FIPV infection warrant further investigation to elucidate host resistance to FIP.

negative: Coronavirus Infection Among Children and Adolescents Coronavirus infection is a global emergency. Over the past few months, there is a rapid increase in the number of cases and deaths due to coronavirus infection. It has been observed that elderly individuals and those with medical co-morbidities are maximally affected. In children and adolescents, coronavirus infection has low mortality as well as the severity of symptoms are less. Children and adolescents with immunocompromised state, malnutrition, medical co-morbidities and poor hygiene are at higher risk of contracting coronavirus infection. Minimizing this risk factors and adopting appropriate prevention measures will be helpful in limiting the spread of infection as there is no specific treatment and immunization available to date to address this serious issue. This chapter highlights the issues and challenges of coronavirus infection in children and adolescents.

negative: The local stability of a modified multi-strain SIR model for emerging viral strains We study a novel multi-strain SIR epidemic model with selective immunity by vaccination. A newer strain is made to emerge in the population when a preexisting strain has reached equilibrium. We assume that this newer strain does not exhibit cross-immunity with the original strain, hence those who are vaccinated and recovered from the original strain become susceptible to the newer strain. Recent events involving the COVID-19 virus demonstrates that it is possible for a viral strain to emerge from a population at a time when the influenza virus, a well-known virus with a vaccine readily available for some of its strains, is active in a population. We solved for four different equilibrium points and investigated the conditions for existence and local stability. The reproduction number was also determined for the epidemiological model and found to be consistent with the local stability condition for the disease-free equilibrium.

negative: Recent progress of immunology research in China

negative: Emerging and reemerging respiratory viral infections up to Covid-19 Infectious diseases remain as the significant causes of human and animal morbidity and mortality, leading to extensive outbreaks and epidemics. Acute respiratory viral diseases claim over 4 million deaths and cause millions of hospitalizations in developing countries every year. Emerging viruses, especially the RNA viruses, are more pathogenic since most people have no herd immunity. The RNA viruses can adapt to the rapidly changing global and local environment due to the high error rate of their polymerases that replicate their genomes. Currently, coronavirus disease 2019 (COVID-19) is determined as an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which was first identified in 2019 in Wuhan. Herein we discuss emerging and reemerging respiratory viral infections till to SARS-CoV-2.

negative: Lactogenic Immunity to Transmissible Gastroenteritis (TGE) of swine induced by the attenuated nouzilly strain of TGE virus: Passive protection of piglets and detection of serum and milk antibody classes by ELISA Abstract Piglets of eight sows vaccinated by different routes with the attenuated TGE mutant coronavirus, Nouzilly (N) strain, and piglets from two field seropositive sows were challenged with a virulent TGE strain. On the day of challenge and 10 days after challenge, milk and serum samples from sows were analysed for their level of neutralizing antibodies, total immunoglobulin classes and TGE antibody classes by an ELISA. No direct relationship was seen between the level of protection of the litters and the titres of the different antibody classes on the day of challenge. However, an inverse correlation was seen 10 days after challenge between protection and the level of TGE antibodies.

negative: The spread of novel coronavirus has created an alarming situation worldwide

negative: Estimation of true number of COVID-19 infected people in Japan using LINE questionnaire The authors estimated the true number of COVID-19 infected people in Japan using the LINE questionnaire data and the PCR test results. A statistically significant correlation was observed between the infection rate per prefecture with PCR test and the rate of high fever. Using this correlation, true number of COVID-19 infected people in Japan was estimated approximately twenty thousand (+/− ten thousand) as of April 1, 2020.

negative: Immunization with Live Human Rhinovirus (HRV) 16 Induces Protection in Cotton Rats against HRV14 Infection Human rhinoviruses (HRVs) are the main cause of cold-like illnesses, and currently no vaccine or antiviral therapies against HRVs are available to prevent or mitigate HRV infection. There are more than 150 antigenically heterogeneous HRV serotypes, with ∼90 HRVs belonging to major group species A and B. Development of small animal models that are susceptible to infection with major group HRVs would be beneficial for vaccine research. Previously, we showed that the cotton rat (Sigmodon hispidus) is semi-permissive to HRV16 (major group, species HRV-A virus) infection, replicating in the upper and lower respiratory tracts with measurable pathology, mucus production, and expression of inflammatory mediators. Herein, we report that intranasal infection of cotton rats with HRV14 (major group, species HRV-B virus) results in isolation of infectious virus from the nose and lung. Similar to HRV16, intramuscular immunization with live HRV14 induces homologous protection that correlated with high levels of serum neutralizing antibodies. Vaccination and challenge experiments with HRV14 and HRV16 to evaluate the development of cross-protective immunity demonstrate that intramuscular immunization with live HRV16 significantly protects animals against HRV14 challenge. Determination of the immunological mechanisms involved in heterologous protection and further characterization of infection with other major HRV serotypes in the cotton rat could enhance the robustness of the model to define heterotypic relationships between this diverse group of viruses and thereby increase its potential for development of a multi-serotype HRV vaccine.

negative: Could Intravenous Immunoglobulin Collected from Recovered Coronavirus Patients Protect against COVID-19 and Strengthen the Immune System of New Patients? The emergence of the novel coronavirus in Wuhan, China, which causes severe respiratory tract infections in humans (COVID-19), has become a global health concern Most coronaviruses infect animals but can evolve into strains that cross the species barrier and infect humans At the present, there is no single specific vaccine or efficient antiviral therapy against COVID-19 Recently, we showed that intravenous immunoglobulin (IVIg) treatment reduces inflammation of intestinal epithelial cells and eliminates overgrowth of the opportunistic human fungal pathogen Candida albicans in the murine gut Immunotherapy with IVIg could be employed to neutralize COVID-19 However, the efficacy of IVIg would be better if the immune IgG antibodies were collected from patients who have recovered from COVID-19 in the same city, or the surrounding area, in order to increase the chance of neutralizing the virus These immune IgG antibodies will be specific against COVID-19 by boosting the immune response in newly infected patients Different procedures may be used to remove or inactivate any possible pathogens from the plasma of recovered coronavirus patient derived immune IgG, including solvent/detergent, 60 °C heat-treatment, and nanofiltration Overall, immunotherapy with immune IgG antibodies combined with antiviral drugs may be an alternative treatment against COVID-19 until stronger options such as vaccines are available

negative: Antibody-Validated Proteins in Inflamed Islets of Fulminant Type 1 Diabetes Profiled by Laser-Capture Microdissection Followed by Mass Spectrometry BACKGROUND: There are no reports of proteomic analyses of inflamed islets in type 1 diabetes. PROCEDURES: Proteins expressed in the islets of enterovirus-associated fulminant type 1 diabetes (FT1DM) with extensive insulitis were identified by laser-capture microdissection mass spectrometry using formalin-fixed paraffin-embedded pancreatic tissues. RESULTS: Thirty-eight proteins were identified solely in FT1DM islets, most of which have not been previously linked to type 1 diabetes. Five protein-protein interacting clusters were identified, and the cellular localization of selected proteins was validated immunohistochemically. Migratory activity-related proteins, including plastin-2 (LCP1), moesin (MSN), lamin-B1 (LMNB1), Ras GTPase-activating-like protein (IQGAP1) and others, were identified in CD8(+) T cells and CD68(+) macrophages infiltrated to inflamed FT1DM islets. Proteins involved in successive signaling in innate/adaptive immunity were identified, including SAM domain and HD domain-containing protein 1 (SAMHD1), Ras GTPase-activating-like protein (IQGAP1), proteasome activator complex subunit 1 (PSME1), HLA class I histocompatibility antigen (HLA-C), and signal transducer and activator of transcription 1-alpha/beta (STAT1). Angiogenic (thymidine phosphorylase (TYMP)) and anti-angiogenic (tryptophan-tRNA ligase (WARS)) factors were identified in migrating CD8(+) T cells and CD68(+) macrophages. Proteins related to virus replication and cell proliferation, including probable ATP-dependent RNA helicase DEAD box helicase 5 (DDX5) and heterogeneous nuclear ribonucleoprotein H (HNRNPH1), were identified. The anti-apoptotic protein T-complex protein 1 subunit epsilon (CCT5), the anti-oxidative enzyme 6-phosphogluconate dehydrogenase (PDG), and the anti-viral and anti-apoptotic proteins serpin B6 (SERPINB6) and heat shock 70 kDa protein1-like (HSPA1L), were identified in FT1DM-affected islet cells. CONCLUSION: The identified FT1DM-characterizing proteins include those involved in aggressive beta cell destruction through massive immune cell migration and proteins involved in angiogenesis and islet vasculature bleeding, cell repair, and anti-inflammatory processes. Several target proteins for future type 1 diabetes interventions were identified.

negative: Emergence of a Novel Coronavirus, Severe Acute Respiratory Syndrome Coronavirus 2: Biology and Therapeutic Options The new decade of the 21(st) century (2020) started with the emergence of a novel coronavirus known as SARS-CoV-2 that caused an epidemic of coronavirus disease (COVID-19) in Wuhan, China. It is the third highly pathogenic and transmissible coronavirus after severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV) emerged in humans. The source of origin, transmission to humans, and mechanisms associated with the pathogenicity of SARS-CoV-2 are not yet clear, however, its resemblance to SARS-CoV and several other bat coronaviruses was recently confirmed through genome sequencing-related studies. The development of therapeutic strategies is necessary in order to prevent further epidemics and cure infections. In this review, we summarize current information about the emergence, origin, diversity, and epidemiology of three pathogenic coronaviruses with a specific focus on the current outbreak in Wuhan, China. Furthermore, we discuss the clinical features and potential therapeutic options that may be effective against SARS-CoV-2.

negative: The outlook for diagnostic purposes of the 2019‐novel coronavirus disease At the end of December 2019, a novel acute respiratory syndrome coronavirus 2 (SARS‐CoV2) appeared as the third unheard of outbreak of human coronavirus infection in the 21st century. First, in Wuhan, China, the novel SARS‐CoV2 was named by the World Health Organization (WHO), as 2019‐nCOV (COVID‐19), and spread extremely all over the world. SARS‐CoV2 is transmitted to individuals by human‐to‐human transmission leading to severe viral pneumonia and respiratory system injury. SARS‐CoV2 elicits infections from the common cold to severe conditions accompanied by lung injury, acute respiratory distress syndrome, and other organ destruction. There is a possibility of virus transmission from asymptomatic cases as active carriers, in addition to symptomatic ones, which is a crucial crisis of COVID‐19 that should be considered. Hence, paying more attention to the accurate and immediate diagnosis of suspected and infected cases can be a great help in preventing the rapid spread of the virus, improving the disease prognosis, and controlling the pandemic. In this review, we provide a comprehensive and up‐to‐date overview of the different types of Clinical and Para‐clinical diagnostic methods and their practical features, which can help understand better the applications and capacities of various diagnostic approaches for COVID‐19 infected cases.

negative: Assay Techniques and Test Development for COVID-19 Diagnosis An ongoing theme of the COVID-19 pandemic is the need for widespread availability of accurate and eﬃcient diagnostic testing for detection of SARS-CoV-2 and antiviral antibodies in infected individuals. This report describes various assay techniques and tests for COVID-19 diagnosis. Most tests for early detection of SARS-CoV-2 RNA rely on the reverse transcription-polymerase chain reaction, but isothermal nucleic acid ampliﬁcation assays, including transcription-mediated ampliﬁcation and CRISPR-based methodologies, are promising alternatives. Identiﬁcation of individuals who have developed antibodies to the SARS-CoV-2 virus requires serological tests, including enzyme-linked immunosorbent assay (ELISA) and lateral ﬂow immunoassay. This report also provides an overview of current development in COVID-19 diagnostic techniques and products to facilitate future improvement and innovation.

negative: New insights on the antiviral effects of chloroquine against coronavirus: what to expect for COVID-19? ABSTRACT Recently, a novel coronavirus (2019-nCoV), officially known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged in China. Despite drastic containment measures, the spread of this virus is ongoing. SARS-CoV-2 is the aetiological agent of coronavirus disease 2019 (COVID-19) characterised by pulmonary infection in humans. The efforts of international health authorities have since focused on rapid diagnosis and isolation of patients as well as the search for therapies able to counter the most severe effects of the disease. In the absence of a known efficient therapy and because of the situation of a public-health emergency, it made sense to investigate the possible effect of chloroquine/hydroxychloroquine against SARS-CoV-2 since this molecule was previously described as a potent inhibitor of most coronaviruses, including SARS-CoV-1. Preliminary trials of chloroquine repurposing in the treatment of COVID-19 in China have been encouraging, leading to several new trials. Here we discuss the possible mechanisms of chloroquine interference with the SARS-CoV-2 replication cycle.

negative: Conserved epitopes of influenza A virus inducing protective immunity and their prospects for universal vaccine development Influenza A viruses belong to the best studied viruses, however no effective prevention against influenza infection has been developed. The emerging of still new escape variants of influenza A viruses causing epidemics and periodic worldwide pandemics represents a threat for human population. Therefore, current, hot task of influenza virus research is to look for a way how to get us closer to a universal vaccine. Combination of chosen conserved antigens inducing cross-protective antibody response with epitopes activating also cross-protective cytotoxic T-cells would offer an attractive strategy for improving protection against drift variants of seasonal influenza viruses and reduces the impact of future pandemic strains. Antigenically conserved fusion-active subunit of hemagglutinin (HA2 gp) and ectodomain of matrix protein 2 (eM2) are promising candidates for preparation of broadly protective HA2- or eM2-based vaccine that may aid in pandemic preparedness. Overall protective effect could be achieved by contribution of epitopes recognized by cytotoxic T-lymphocytes (CTL) that have been studied extensively to reach much broader control of influenza infection. In this review we present the state-of-art in this field. We describe known adaptive immune mechanisms mediated by influenza specific B- and T-cells involved in the anti-influenza immune defense together with the contribution of innate immunity. We discuss the mechanisms of neutralization of influenza infection mediated by antibodies, the role of CTL in viral elimination and new approaches to develop epitope based vaccine inducing cross-protective influenza virus-specific immune response.

negative: Serum albumin-mediated strategy for the effective targeting of SARS-CoV-2 Abstract Novel coronavirus (NCoV-19), also known as SARS CoV-2, is a pathogen causing an emerging infection that rapidly increases in incidence and geographic range, is associated with the ever-increasing morbidity and mortality rates, and shows sever economic impact worldwide. The WHO declares the NCoV-19 infection disease (COVID-19) a Public Health Emergency of International Concern on 30 January 2020 and subsequently, on March 11, 2020, declared it a Global Pandemic. Although some people infected with SARS CoV-2 have no symptoms, the spectrum of symptomatic infection ranges from mild to critical, with most COVID-19 infections being not severe. The common mild symptoms include body aches, dry cough, fatigue, low-grade fever, nasal congestion, and sore throat. More severe COVID-19 symptoms are typical of pneumonia, and upon progression, the patient’s condition can worsen with severe respiratory and cardiac problems. Currently, there is no drug or vaccine for curing patients. It has been observed that people with challenged immunity are highly prone to SARS CoV-2 infection and least likely to recover. Also, older adults and people of any age with serious underlying medical conditions might be at higher risk for severe forms of COVID-19. We are suggesting here a strategy for the COVID-19 treatment that could be effective in curing the patients in the current scenario when no efficient medicine or Vaccine is currently available, and Clinicians solely depend upon the performing trials with drugs with known antiviral activities. Our proposed strategy is based on the compilation of published scientific research and concepts. The different published research indicates the success of a similar strategy in different physiological conditions, and such a strategy is widely studied at the cellular level and in animal models.

negative: Host Factors in Coronavirus Replication Coronaviruses are pathogens with a serious impact on human and animal health. They mostly cause enteric or respiratory disease, which can be severe and life threatening, e.g., in the case of the zoonotic coronaviruses causing severe acute respiratory syndrome (SARS) and Middle East Respiratory Syndrome (MERS) in humans. Despite the economic and societal impact of such coronavirus infections, and the likelihood of future outbreaks of additional pathogenic coronaviruses, our options to prevent or treat coronavirus infections remain very limited. This highlights the importance of advancing our knowledge on the replication of these viruses and their interactions with the host. Compared to other +RNA viruses, coronaviruses have an exceptionally large genome and employ a complex genome expression strategy. Next to a role in basic virus replication or virus assembly, many of the coronavirus proteins expressed in the infected cell contribute to the coronavirus-host interplay. For example, by interacting with the host cell to create an optimal environment for coronavirus replication, by altering host gene expression or by counteracting the host’s antiviral defenses. These coronavirus–host interactions are key to viral pathogenesis and will ultimately determine the outcome of infection. Due to the complexity of the coronavirus proteome and replication cycle, our knowledge of host factors involved in coronavirus replication is still in an early stage compared to what is known for some other +RNA viruses. This review summarizes our current understanding of coronavirus–host interactions at the level of the infected cell, with special attention for the assembly and function of the viral RNA-synthesising machinery and the evasion of cellular innate immune responses.

negative: A more detailed picture of the epidemiology of Middle East respiratory syndrome coronavirus

negative: Bioinformatic prediction of potential T cell epitopes for SARS-Cov-2 To control and prevent the current COVID-19 pandemic, the development of novel vaccines is an emergent issue. In addition, we need to develop tools that can measure/monitor T-cell and B-cell responses to know how our immune system is responding to this deleterious virus. However, little information is currently available about the immune target epitopes of novel coronavirus (SARS-CoV-2) to induce host immune responses. Through a comprehensive bioinformatic screening of potential epitopes derived from the SARS-CoV-2 sequences for HLAs commonly present in the Japanese population, we identified 2013 and 1399 possible peptide epitopes that are likely to have the high affinity (<0.5%- and 2%-rank, respectively) to HLA class I and II molecules, respectively, that may induce CD8(+) and CD4(+) T-cell responses. These epitopes distributed across the structural (spike, envelope, membrane, and nucleocapsid proteins) and the nonstructural proteins (proteins corresponding to six open reading frames); however, we found several regions where high-affinity epitopes were significantly enriched. By comparing the sequences of these predicted T cell epitopes to the other coronaviruses, we identified 781 HLA-class I and 418 HLA-class II epitopes that have high homologies to SARS-CoV. To further select commonly-available epitopes that would be applicable to larger populations, we calculated population coverages based on the allele frequencies of HLA molecules, and found 2 HLA-class I epitopes covering 83.8% of the Japanese population. The findings in the current study provide us valuable information to design widely-available vaccine epitopes against SARS-CoV-2 and also provide the useful information for monitoring T-cell responses.

negative: SARS-like cluster of circulating bat coronavirus pose threat for human emergence The emergence of Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) and Middle East Respiratory Syndrome (MERS)-CoV underscores the threat of cross-species transmission events leading to outbreaks in humans. In this study, we examine the disease potential for SARS-like CoVs currently circulating in Chinese horseshoe bat populations. Utilizing the SARS-CoV infectious clone, we generated and characterized a chimeric virus expressing the spike of bat coronavirus SHC014 in a mouse adapted SARS-CoV backbone. The results indicate that group 2b viruses encoding the SHC014 spike in a wild type backbone can efficiently utilize multiple ACE2 receptor orthologs, replicate efficiently in primary human airway cells, and achieve in vitro titers equivalent to epidemic strains of SARS-CoV. Additionally, in vivo experiments demonstrate replication of the chimeric virus in mouse lung with notable pathogenesis. Evaluation of available SARS-based immune-therapeutic and prophylactic modalities revealed poor efficacy; both monoclonal antibody and vaccine approaches failed to neutralize and protect from CoVs utilizing the novel spike protein. Importantly, based on these findings, we synthetically rederived an infectious full length SHC014 recombinant virus and demonstrate robust viral replication both in vitro and in vivo. Together, the work highlights a continued risk of SARS-CoV reemergence from viruses currently circulating in bat populations.

negative: NSAIDs in patients with viral infections, including Covid-19: victims or perpetrators? Abstract Taking anti-inflammatory drugs, including non-steroidal (NSAIDs), during Covid-19 infection, how much is risky? The French Minister of Health, who has raised an alarm on a possible risk deriving from the use of ibuprofen for the control of fever and other symptoms during the disease, opened the debate a few days ago. In this paper we examine available evidence from preclinical and clinical studies that had analysed the role of COX in the inflammatory process and the effects of NSAIDs in patients with infections. Most of the published studies that suggested not protective effects of NSAIDs were mainly performed in vitro or on animals. Therefore, their meaning in humans is to be considered with great caution. Based also on data suggesting protective effects of NSAIDs, we concluded that currently there is no evidence suggesting a correlation between NSAIDs and a worsening of infections. Further studies will be certainly needed to better define the role of NSAIDs and particularly COX2 inhibitors in patients with infections. In the meantime, we must wait for results of the revision started by the PRAC on May 2019 on the association ibuprofen/ketoprofen and worsening of infections. Since nowadays no scientific evidence establishes a correlation between NSAIDS and worsening of COVID-19, patients should be advice against any NSAIDs self-medication when COVID-19 like symptoms are present.

negative: Editorial: Archives of Virology’s 80th anniversary symposium—6 months later

negative: Vaccination strategies to combat novel corona virus SARS-CoV-2 The 2019-novel coronavirus disease (COVID-19) is caused by SARS-CoV-2 is transmitted from human to human has recently reported in China. Now COVID-19 has been spread all over the world and declared epidemics by WHO. It has caused a Public Health Emergency of International Concern. The elderly and people with underlying diseases are susceptible to infection and prone to serious outcomes, which may be associated with acute respiratory distress syndrome (ARDS) and cytokine storm. Due to the rapid increase of SARS-CoV-2 infections and unavailability of antiviral therapeutic agents, developing an effective SAR-CoV-2 vaccine is urgently required. SARS-CoV-2 which is genetically similar to SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV) is an enveloped, single and positive-stranded RNA virus with a genome comprising 29,891 nucleotides, which encode the 12 putative open reading frames responsible for the synthesis of viral structural and nonstructural proteins which are very similar to SARS-CoV and MERS-CoV proteins. In this review we have summarized various vaccine candidates i.e., nucleotide, subunit and vector based as well as attenuated and inactivated forms, which have already been demonstrated their prophylactic efficacy against MERS-CoV and SARS-CoV, so these candidates could be used as a potential tool for the development of a safe and effective vaccine against SARS-CoV-2.

negative: Clinical Features of Patients Infected with the 2019 Novel Coronavirus (COVID-19) in Shanghai, China Background: Since mid-December 2019, a cluster of pneumonia-like diseases caused by a novel coronavirus, now designated COVID-19 by the WHO, emerged in Wuhan city and rapidly spread throughout China. Here we identify the clinical characteristics of COVID-19 in a cohort of patients in Shanghai. Methods: Cases were confirmed by real-time RT-PCR and were analysed for demographic, clinical, laboratory and radiological features. Results: Of 198 patients, the median duration from disease onset to hospital admission was 4 days. The mean age of the patients was 50.1 years, and 51.0% patients were male. The most common symptom was fever. Less than half of the patients presented with respiratory systems including cough, sputum production, itchy or sore throat, shortness of breath, and chest congestion. 5.6% patients had diarrhoea. On admission, T lymphocytes were decreased in 45.8% patients. Ground glass opacity was the most common radiological finding on chest computed tomography. 9.6% were admitted to the ICU because of the development of organ dysfunction. Compared with patients not treated in ICU, patients treated in the ICU were older, had longer waiting time to admission, fever over 38.5o C, dyspnoea, reduced T lymphocytes, elevated neutrophils and organ failure. Conclusions: In this single centre cohort of COVID-19 patients, the most common symptom was fever, and the most common laboratory abnormality was decreased blood T cell counts. Older age, male, fever over 38.5oC, symptoms of dyspnoea, and underlying comorbidity, were the risk factors most associated with severity of disease. Key words: 2019 novel coronavirus; acute respiratory infection; risk factors for disease severity

negative: Potential of immunomodulatory host defense peptides as novel anti-infectives A fundamentally new strategy for the treatment of infectious disease is the modulation of host immune responses to enhance clearance of infectious agents and reduce tissue damage due to inflammation. Antimicrobial host defense peptides have been investigated for their potential as a new class of antimicrobial drugs. Recently their immunomodulatory activities have begun to be appreciated. Modulation of innate immunity by synthetic variants of host defense peptides, called innate defense regulators (IDRs), is protective without direct antimicrobial action. We discuss the potential and current limitations in exploiting the immunomodulatory activity of IDRs as a novel anti-infective pathway. IDRs show significant promise and current research is uncovering mechanistic information that will aid in the future development of IDRs for clinical use.

negative: Studies on the relationship between coronaviruses from the intestinal and respiratory tracts of calves An immunofluorescence test on smears of nasal epithelial cells was used to detect coronavirus infection in the respiratory tract of calves. Thirteen gnotobiotic calves were infected with coronavirus isolates derived from faeces or respiratory material: virus was detected in faeces and nasal swabs from all animals. In 115 calves from a field survey, there was a significant association between coronavirus excretion from both respiratory and enteric routes in calves with diarrhoea. In a further 12 calves, at necropsy, the predilection sites for coronavirus growth were the distal small intestine, large intestine and the epithelia of the nasal cavity and trachea. Antigen was not found in lung tissue by immunofluoresence or immunoperoxidase staining. Infection with enteric coronavirus induced immunity to reinfection and to heterologous challenge with two coronavirus isolates derived from the respiratory tract. Nine coronaviruses were cultivated, cloned and antisera to three were prepared in pigs. There was complete virus neutralisation in tests with homologous sera and significant cross reactions with the eight other isolates which were of intestinal and respiratory origin. Thus, these bovine coronavirus isolates belonged to the same serotype despite the source of virus.

negative: ABPP and Host–Virus Interactions Successful viral infection, as well as any resultant antiviral response, relies on numerous sequential interactions between host and viral factors. These interactions can take the form of affinity-based interactions between viral and host macromolecules or active, enzyme-based interactions, consisting both of direct enzyme activity performed by viral enzymes and indirect modulation of the activity of the host cell’s enzymes via viral interference. This activity has the potential to transform the local microenvironment to the benefit or detriment of both the virus and the host, favouring either the continuation of the viral life cycle or the host’s antiviral response. Comprehensive characterisation of enzymatic activity during viral infection is therefore necessary for the understanding of virally induced diseases. Activity-based protein profiling techniques have been established as effective and practicable tools with which to interrogate the regulation of enzymes’ catalytic activity and the roles played by these enzymes in various cell processes. This paper will review the contributions of these techniques in characterising the roles of both host and viral enzymes during viral infection in humans.

negative: Characterization of spike glycoprotein of SARS-CoV-2 on virus entry and its immune cross-reactivity with SARS-CoV Since 2002, beta coronaviruses (CoV) have caused three zoonotic outbreaks, SARS-CoV in 2002–2003, MERS-CoV in 2012, and the newly emerged SARS-CoV-2 in late 2019. However, little is currently known about the biology of SARS-CoV-2. Here, using SARS-CoV-2 S protein pseudovirus system, we confirm that human angiotensin converting enzyme 2 (hACE2) is the receptor for SARS-CoV-2, find that SARS-CoV-2 enters 293/hACE2 cells mainly through endocytosis, that PIKfyve, TPC2, and cathepsin L are critical for entry, and that SARS-CoV-2 S protein is less stable than SARS-CoV S. Polyclonal anti-SARS S1 antibodies T62 inhibit entry of SARS-CoV S but not SARS-CoV-2 S pseudovirions. Further studies using recovered SARS and COVID-19 patients’ sera show limited cross-neutralization, suggesting that recovery from one infection might not protect against the other. Our results present potential targets for development of drugs and vaccines for SARS-CoV-2.

negative: Ambulant erworbene Pneumonie bei Erwachsenen Die ambulant erworbene Pneumonie ist die häufigste ernste Infektionserkrankung in Deutschland. Die Mehrzahl der Fälle wird ambulant behandelt. Die Diagnose wird klinisch durch Zeichen der Infektion, respiratorischen Symptomen und dem Auskultationsbefund gestellt und durch den Nachweis eines pneumonischen Infiltrats in der Röntgenaufnahme bestätigt. Der mit Abstand häufigste Erreger bleibt Streptococcus pneumoniae, der in Deutschland unverändert hohe Penicillinempfindlichkeit zeigt. Daneben werden Haemophilus influenzae, Mykoplasmen, Legionellen und Influenza-Viren regelmäßig nachgewiesen. Eine mikrobiologische Diagnostik ist in der Praxis nicht routinemäßig erforderlich. Zur Einschätzung der Prognose und Entscheidung über die Notwendigkeit einer Hospitalisierung dient der CRB65-Score. Die Auswahl der kalkulierten Therapie richtet sich nach Schweregrad der Infektion und Vorliegen von Komorbiditäten. Aminopenicilline sind Mittel erster Wahl bei unkomplizierten Pneumonien. Bei Verdacht auf Mykoplasmen- und Legionelleninfektion ist ein Makrolid oder ein neueres Fluorchinolon indiziert. Wichtige präventive Maßnahmen sind die jährliche Influenzaimpfung und die Pneumokokkenimpfung.

negative: A MULTINATIONAL REPORT TO CHARACTERISE SARS-CoV-2 INFECTION IN PEOPLE WITH CYSTIC FIBROSIS Abstract Information is lacking on the clinical impact of the novel coronavirus, SARS-CoV-2 on people with cystic fibrosis (CF). Our aim was to characterize SARS-CoV-2 infection in people with cystic fibrosis. Methods: Anonymised data submitted by each participating country to their National CF Registry was reported using a standardised template, then collated and summarised. Results: 40 cases have been reported across 8 countries. Of the 40 cases, 31 (78%) were symptomatic for SARS-CoV-2 at presentation, with 24 (60%) having a fever. 70% have recovered, 30% remain unresolved at time of reporting, and no deaths have been submitted. Conclusions: This early report shows good recovery from SARS-CoV-2 in this heterogeneous CF cohort. The disease course does not seem to differ from the general population, but the current numbers are too small to draw firm conclusions and people with CF should continue to strictly follow public health advice to protect themselves from infection.

negative: PEDV and PDCoV Pathogenesis: The Interplay Between Host Innate Immune Responses and Porcine Enteric Coronaviruses Enteropathogenic porcine epidemic diarrhea virus (PEDV) and porcine deltacoronavirus (PDCoV), members of the coronavirus family, account for the majority of lethal watery diarrhea in neonatal pigs in the past decade. These two viruses pose significant economic and public health burdens, even as both continue to emerge and reemerge worldwide. The ability to evade, circumvent or subvert the host’s first line of defense, namely the innate immune system, is the key determinant for pathogen virulence, survival, and the establishment of successful infection. Unfortunately, we have only started to unravel the underlying viral mechanisms used to manipulate host innate immune responses. In this review, we gather current knowledge concerning the interplay between these viruses and components of host innate immunity, focusing on type I interferon induction and signaling in particular, and the mechanisms by which virus-encoded gene products antagonize and subvert host innate immune responses. Finally, we provide some perspectives on the advantages gained from a better understanding of host-pathogen interactions. This includes their implications for the future development of PEDV and PDCoV vaccines and how we can further our knowledge of the molecular mechanisms underlying virus pathogenesis, virulence, and host coevolution.

negative: Immune-complex glomerulonephritis in cats: a retrospective study based on clinico-pathological data, histopathology and ultrastructural features BACKGROUND: Chronic kidney disease (CKD) has typically a non-immune mediated origin in cats and immune-complex glomerulonephritis (ICGN) is scarcely described. Aims of this study were to characterize ICGN by light and electron microscopy and identify associations with clinico-pathological findings. In addition, comparisons between cats with ICGN and non immune-complex glomerulonephritis (non-ICGN) were performed. Renal samples examined between 2010 and 2019 were considered if both light and electron microscopy were performed. Signalment, feline immunodeficiency virus (FIV) and leukemia virus (FeLV) status, serum creatinine concentration, urine protein-to-creatinine (UPC) ratio, systolic blood pressure (SBP) and International Renal Interest Society (IRIS) stage were retrieved and used for comparisons. RESULTS: Sixty-eight client-owned cats were included. Thirty-seven cats (54.4%) had ICGN and 31 (45.6%) non-ICGN. Eighteen (48.6%) with ICGN had membranous glomerulonephropathy (MGN), 14 (37.8%) membranoproliferative glomerulonephritis (MPGN), and 5 (13.5%) mesangioproliferative glomerulonephritis (MeGN). Clinico-pathological data were not associated with any type of ICGN. Among cats with non-ICGN, 11 (35.5%) had end-stage CKD, 9 (29%) focal segmental glomerulosclerosis, 6 (19.4%) global and multifocal mesangiosclerosis, 2 (6.5%) glomerular atrophy, 2 (6.5%) renal dysplasia and 1 (3.1%) amyloidosis. Eight (25.8%) cats with non-ICGN had chronic interstitial nephritis (CIN) grade 1, 13 (41.9%) grade 2 and 10 (32.3%) grade 3; creatinine and UPC ratio increased with CIN grades (p = 0.001, p < 0.001). Cats with ICGN were more frequently FIV or FeLV-infected (OR:11.4; 95%CI:1.4–94.4; p = 0.024), had higher UPC ratio (OR:6.8; 95%CI:2.5–18.2; p < 0.001) and were younger (OR:0.9; 95%CI:0.7–1.0; p = 0.042) than cats with non-ICGN. CONCLUSIONS: MGN and MPGN were the most common morphological diagnoses of ICGN in cats. Unfortunately, none of the investigated findings differentiated ICGN morphological diagnoses. Serum creatinine concentration and UPC ratio were directly associated with grades of CIN (p = 0.001 and p < 0.001, respectively), confirming previous literature. More ICGN than non-ICGN was observed in cats with retroviral infections, younger cats and higher UPC ratio.

negative: COVID-19 Antibody Test / Vaccination Certification: There's an app for that Goal: As the Coronavirus Pandemic of 2019/2020 unfolds, a COVID-19 'Immunity Passport' has been mooted as a way to enable individuals to return back to work. While the quality of antibody testing, the availability of vaccines, and the likelihood of even attaining COVID-19 immunity continue to be researched, we address the issues involved in providing tamper-proof and privacy-preserving certification for test results and vaccinations. Methods: We developed a prototype mobile phone app and requisite decentralized server architecture that facilitates instant verification of tamper-proof test results. Personally identifiable information is only stored at the user's discretion, and the app allows the end-user selectively to present only the specific test result with no other personal information revealed. The architecture, designed for scalability, relies upon (a) the 2019 World Wide Web Consortium standard called 'Verifiable Credentials', (b) Tim Berners-Lee's decentralized personal data platform 'Solid', and (c) a Consortium Ethereum-based blockchain. Results: Our mobile phone app and decentralized server architecture enable the mixture of verifiability and privacy in a manner derived from public/private key pairs and digital signatures, generalized to avoid restrictive ownership of sensitive digital keys and/or data. Benchmark performance tests show it to scale linearly in the worst case, as significant processing is done locally on each app. For the test certificate Holder, Issuer (e.g. healthcare staff, pharmacy) and Verifier (e.g. employer), it is 'just another app' which takes only minutes to use. Conclusions: The app and decentralized server architecture offer a prototype proof of concept that is readily scalable, applicable generically, and in effect 'waiting in the wings' for the biological issues, plus key ethical issues raised in the discussion section, to be resolved.

negative: Should, and how can, exercise be done during a coronavirus outbreak? An interview with Dr. Jeffrey A. Woods

negative: Mucosal immunisation of African green monkeys (Cercopithecus aethiops) with an attenuated parainfluenza virus expressing the SARS coronavirus spike protein for the prevention of SARS Summary Background The outbreak of severe acute respiratory syndrome (SARS) in 2002 was caused by a previously unknown coronavirus—SARS coronavirus (SARS-CoV). We have developed an experimental SARS vaccine for direct immunisation of the respiratory tract, the major site of SARS-coronavirus transmission and disease. Methods We expressed the complete SARS coronavirus envelope spike (S) protein from a recombinant attenuated parainfluenza virus (BHPIV3) that is being developed as a live attenuated, intranasal paediatric vaccine against human parainfluenza virus type 3 (HPIV3). We immunised eight African green monkeys, four with a single dose of BHPIV3/SARS-S and four with a control, BHPIV3/Ctrl, administered via the respiratory tract. A SARS-coronavirus challenge was given to all monkeys 28 days after immunisation. Findings Immunisation of animals with BHPIV3/SARS-S induced the production of SARS-coronavirus-neutralising serum antibodies, indicating that a systemic immune response resulted from mucosal immunisation. After challenge with SARS coronavirus, all monkeys in the control group shed SARS coronavirus, with shedding lasting 5–8 days. No viral shedding occurred in the group immunised with BHPIV3/SARS-S. Interpretation A vectored mucosal vaccine expressing the SARS-coronavirus S protein alone may be highly effective in a single-dose format for the prevention of SARS.

negative: SARS-CoV-2 and gastrointestinal tract: the dark side of the pandemic

negative: Harnessing the Power of T Cells: The Promising Hope for a Universal Influenza Vaccine Next-generation vaccines that utilize T cells could potentially overcome the limitations of current influenza vaccines that rely on antibodies to provide narrow subtype-specific protection and are prone to antigenic mismatch with circulating strains. Evidence from animal models shows that T cells can provide heterosubtypic protection and are crucial for immune control of influenza virus infections. This has provided hope for the design of a universal vaccine able to prime against diverse influenza virus strains and subtypes. However, multiple hurdles exist for the realisation of a universal T cell vaccine. Overall primary concerns are: extrapolating human clinical studies, seeding durable effective T cell resident memory (Trm), population human leucocyte antigen (HLA) coverage, and the potential for T cell-mediated immune escape. Further comprehensive human clinical data is needed during natural infection to validate the protective role T cells play during infection in the absence of antibodies. Furthermore, fundamental questions still exist regarding the site, longevity and duration, quantity, and phenotype of T cells needed for optimal protection. Standardised experimental methods, and eventually simplified commercial assays, to assess peripheral influenza-specific T cell responses are needed for larger-scale clinical studies of T cells as a correlate of protection against influenza infection. The design and implementation of a T cell-inducing vaccine will require a consensus on the level of protection acceptable in the community, which may not provide sterilizing immunity but could protect the individual from severe disease, reduce the length of infection, and potentially reduce transmission in the community. Therefore, increasing the standard of care potentially offered by T cell vaccines should be considered in the context of pandemic preparedness and zoonotic infections, and in combination with improved antibody vaccine targeting methods. Current pandemic vaccine preparedness measures and ongoing clinical trials under-utilise T cell-inducing vaccines, reflecting the myriad questions that remain about how, when, where, and which T cells are needed to fight influenza virus infection. This review aims to bring together basic fundamentals of T cell biology with human clinical data, which need to be considered for the implementation of a universal vaccine against influenza that harnesses the power of T cells.

negative: Protocol of a randomized controlled trial testing inhaled Nitric Oxide in mechanically ventilated patients with severe acute respiratory syndrome in COVID-19 (SARS-CoV-2). INTRODUCTION. Severe acute respiratory syndrome due to novel Coronavirus (SARS-CoV-2) related infection (COVID-19) is characterized by severe ventilation perfusion mismatch leading to refractory hypoxemia. To date, there is no specific treatment available for COVID-19. Nitric oxide is a selective pulmonary vasodilator gas used as a rescue therapy in refractory hypoxemia due to acute respiratory distress syndrome (ARDS). In has also shown invitro and clinical evidence that inhaled nitric oxide gas (iNO) has antiviral activity against other strains of coronavirus. The primary aim of this study is to determine whether inhaled NO improves oxygenation in patients with hypoxic COVID-19. This is a multicenter randomized controlled trial with 1:1 individual allocation. Patients will be blinded to the treatment. METHODS AND ANALYSIS. Intubated patients admitted to the intensive care unit with confirmed SARS-CoV-2 infection and severe hypoxemia will be randomized to receive inhalation of NO (treatment group) or not (control group). Treatment will be stopped when patients are free from hypoxemia for more than 24 hours. The primary outcome evaluates levels of oxygenation between the two groups at 48 hours. Secondary outcomes include rate of survival rate at 28 and 90 days in the two groups, time to resolution of severe hypoxemia, time to achieve negativity of SARS-CoV-2 RT-PCR tests. ETHICS AND DISSEMINATION. The study protocol has been approved by the Investigational Review Board of Xijing Hospital (Xi’an, China) and by the Partners Human Research Committee (Boston, USA). Recruitment will start after approval of both IRBs and local IRBs at other enrolling centers. Results of this study will be published in scientific journals, presented at scientific meetings, reported through flyers and posters, and published on related website or media in combating against this widespread contagious disease. TRIAL REGISTRATION. Clinicaltrials.gov. NCT04306393

negative: Live-attenuated bivalent measles virus-derived vaccines targeting Middle East respiratory syndrome coronavirus induce robust and multifunctional T cell responses against both viruses in an appropriate mouse model Abstract Cases of Middle East respiratory syndrome coronavirus (MERS-CoV) continue to occur, making it one of the WHO´s targets for accelerated vaccine development. One vaccine candidate is based on live-attenuated measles virus (MV) vaccine encoding the MERS-CoV spike glycoprotein (MERS-S). MVvac2-MERS-S(H) induces robust humoral and cellular immunity against MERS-S mediating protection. Here, the induction and nature of immunity after vaccination with MVvac2-MERS-S(H) or novel MVvac2-MERS-N were further characterized. We focused on the necessity for vector replication and the nature of induced T cells, since functional CD8+ T cells contribute importantly to clearance of MERS-CoV. While no immunity against MERS-CoV or MV was detected in MV-susceptible mice after immunization with UV-inactivated virus, replication-competent MVvac2-MERS-S(H) triggered robust neutralizing antibody titers also in adult mice. Furthermore, a significant fraction of MERS CoV-specific CD8+ T cells and MV-specific CD4+ T cells simultaneously expressing IFN-γ and TNF-α were induced, revealing that MVvac2-MERS-S(H) induces multifunctional cellular immunity.

negative: Analytical Validation of a COVID-19 qRT-PCR Detection Assay Using a 384-well Format and Three Extraction Methods The COVID-19 global pandemic is an unprecedented health emergency. Insufficient access to testing has hampered effective public health interventions and patient care management in a number of countries. Furthermore, the availability of regulatory-cleared reagents has challenged widespread implementation of testing. We rapidly developed a qRT-PCR SARS-CoV-2 detection assay using a 384-well format and tested its analytic performance across multiple nucleic acid extraction kits. Our data shows robust analytic accuracy on residual clinical biospecimens. Limit of detection sensitivity and specificity was confirmed with currently available commercial reagents. Our methods and results provide valuable information for other high-complexity laboratories seeking to develop effective, local, laboratory-developed procedures with high-throughput capability to detect SARS-CoV-2.

negative: Expression of the SARS-CoV-2 cell receptor gene ACE2 in a wide variety of human tissues BACKGROUND: Since its discovery in December 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected more than 2 180 000 people worldwide and has caused more than 150 000 deaths as of April 16, 2020. SARS-CoV-2, which is the virus causing coronavirus disease 2019 (COVID-19), uses the angiotensin-converting enzyme 2 (ACE2) as a cell receptor to invade human cells. Thus, ACE2 is the key to understanding the mechanism of SARS-CoV-2 infection. This study is to investigate the ACE2 expression in various human tissues in order to provide insights into the mechanism of SARS-CoV-2 infection. METHODS: We compared ACE2 expression levels across 31 normal human tissues between males and females and between younger (ages ≤ 49 years) and older (ages > 49 years) persons using two-sided Student’s t test. We also investigated the correlations between ACE2 expression and immune signatures in various tissues using Pearson’s correlation test. RESULTS: ACE2 expression levels were the highest in the small intestine, testis, kidneys, heart, thyroid, and adipose tissue, and were the lowest in the blood, spleen, bone marrow, brain, blood vessels, and muscle. ACE2 showed medium expression levels in the lungs, colon, liver, bladder, and adrenal gland. ACE2 was not differentially expressed between males and females or between younger and older persons in any tissue. In the skin, digestive system, brain, and blood vessels, ACE2 expression levels were positively associated with immune signatures in both males and females. In the thyroid and lungs, ACE2 expression levels were positively and negatively associated with immune signatures in males and females, respectively, and in the lungs they had a positive and a negative correlation in the older and younger groups, respectively. CONCLUSIONS: Our data indicate that SARS-CoV-2 may infect other tissues aside from the lungs and infect persons with different sexes, ages, and races equally. The different host immune responses to SARS-CoV-2 infection may partially explain why males and females, young and old persons infected with this virus have markedly distinct disease severity. This study provides new insights into the role of ACE2 in the SARS-CoV-2 pandemic.

negative: Surviving Deadly Lung Infections: Innate Host Tolerance Mechanisms in the Pulmonary System Much research on infectious diseases focuses on clearing the pathogen through the use of antimicrobial drugs, the immune response, or a combination of both. Rapid clearance of pathogens allows for a quick return to a healthy state and increased survival. Pathogen-targeted approaches to combating infection have inherent limitations, including their pathogen-specific nature, the potential for antimicrobial resistance, and poor vaccine efficacy, among others. Another way to survive an infection is to tolerate the alterations to homeostasis that occur during a disease state through a process called host tolerance or resilience, which is independent from pathogen burden. Alterations in homeostasis during infection are numerous and include tissue damage, increased inflammation, metabolic changes, temperature changes, and changes in respiration. Given its importance and sensitivity, the lung is a good system for understanding host tolerance to infectious disease. Pneumonia is the leading cause of death for children under five worldwide. One reason for this is because when the pulmonary system is altered dramatically it greatly impacts the overall health and survival of a patient. Targeting host pathways involved in maintenance of pulmonary host tolerance during infection could provide an alternative therapeutic avenue that may be broadly applicable across a variety of pathologies. In this review, we will summarize recent findings on tolerance to host lung infection. We will focus on the involvement of innate immune responses in tolerance and how an initial viral lung infection may alter tolerance mechanisms in leukocytic, epithelial, and endothelial compartments to a subsequent bacterial infection. By understanding tolerance mechanisms in the lung we can better address treatment options for deadly pulmonary infections.

negative: A Pathophysiological Perspective on COVID-19's Lethal Complication: From Viremia to Hypersensitivity Pneumonitis-like Immune Dysregulation. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the coronavirus responsible for our recent coronavirus disease 2019 pandemic, is driving a lung immunopathology that strongly resembles a severe form of hypersensitivity pneumonitis (HP). A review of recent Severe acute respiratory syndrome-related coronavirus (SARS-CoV) and SARS-CoV-2 medical reports, as well as described characteristics of HP, lead us to postulate a theory for SARS-CoV-2 severe disease. We propose that the novel SARS-CoV-2 can act as a trigger and substrate of an HP-like severe immune reaction especially in genetically vulnerable individuals in addition to those with immune senescence and dysregulation. Accordingly, the purpose of our letter is to shift the emphasis of concern surrounding immune activity from viral infection to an HP-like severe immune reaction. We review similarities in disease presentation between infection and allergy, relevant immunopathology, and outline phases of SARS-CoV-2 disease with perspectives on therapy and critical care. Altogether, the favored course is to begin treatments that address the disease at the earliest phase before immune dysregulation leading to uncontrolled pulmonary inflammation.

negative: Review and analysis of current responses to COVID-19 in Indonesia: Period of January to March 2020 Abstract The world is under pressure from the novel COVID-19 pandemic. Indonesia is the fourth most populous country in the world and predicted to be affected significantly over a longer time period. Our paper aims to provide detailed reporting and analyses of the present rapid responses to COVID-19, between January and March 2020, in Indonesia. We particularly highlight responses taken by the governments, non-government organisations and the community. We outline gaps and limitations in the responses, based on our rapid analysis of media contents, from government speeches and reports, social and mass media platforms. We present five recommendations toward more rapid, effective, and comprehensive responses.

negative: COVID-19 SCREENING AND MONITORING OF ASYMPTOMATIC HEALTH WORKERS WITH A RAPID SEROLOGICAL TEST Background Health workers are at high risk for SARS-CoV-2 infection and, if asymptomatic, for transmitting the virus on to fragile cancer patients. Materials and method We monitored health care workers (HCW) of our Cancer Institute with the rapid serological test Viva-DiagTM analyzing COVID-19 associated-IgG/IgM. Test were performed at time 0 and after 14 days; Rt-PCR and CLIA assays were also perfoRmed in positive Viva-DiagTM cases. 606 and 393 HCW had blood sample taken at time 0 and 14, respectively. Results Overall, 9 HCW (1.5%) resulted not-negative at Viva-DiagTM and one of them was confirmed positive for SARS-COV2 infection at RT-PCR oropharingeal swab. At time 0, all 9 cases showed some IgM expression and only one IgG; after 14 days IgM persisted in all cases while IgG became evident in 4 ones. A parallel CLIA test was performed in 23 quaratined subjetcs and in all Viva-Diag not negative cases. CLIA confirmed a positive level of IgM in 5/13 positive Viva-Diag cases; conversely, IgG was confirmed positive at CLIA in 4/5 cases positive at Viva-Diag. These results pose the question of different performances of the two tests. Conclusions Our study suggest that Viva-Diag assay can be of help in individualizing SARS_COV2 infected people fisrt of all in cohorts of subjetcs with high prevalence. Different performances of serological colorimetric and CLIA tools remain to be ascertained.

negative: Explaining the Bomb-Like Dynamics of COVID-19 with Modeling and the Implications for Policy Using a Bayesian approach to epidemiological compartmental modeling, we demonstrate the bomb-like behavior of exponential growth in COVID-19 cases can be explained by transmission of asymptomatic and mild cases that are typically unreported at the beginning of pandemic events due to lower prevalence of testing. We studied the exponential phase of the pandemic in Italy, Spain, and South Korea, and found the R0 to be 2.56 (95% CrI, 2.41-2.71), 3.23 (95% CrI, 3.06-3.4), and 2.36 (95% CrI, 2.22-2.5) if we use Bayesian priors that assume a large portion of cases are not detected. Weaker priors regarding the detection rate resulted in R0 values of 9.22 (95% CrI, 9.01-9.43), 9.14 (95% CrI, 8.99-9.29), and 8.06 (95% CrI, 7.82-8.3) and assumes nearly 90% of infected patients are identified. Given the mounting evidence that potentially large fractions of the population are asymptomatic, the weaker priors that generate the high R0 values to fit the data required assumptions about the epidemiology of COVID-19 that do not fit with the biology, particularly regarding the timeframe that people remain infectious. Our results suggest that models of transmission assuming a relatively lower R0 value that do not consider a large number of asymptomatic cases can result in misunderstanding of the underlying dynamics, leading to poor policy decisions and outcomes.

negative: Protection against homo and hetero-subtypic inﬂuenza A virus by optimized M2e DNA vaccine Current influenza vaccines provide hemagglutinin strain-specific protection, but rarely provide cross-protection against divergent strains. It is, therefore, particularly important to develop a universal vaccine against conserved proteins or conserved regions of the virus. In this study, we used N-terminal extracellular region of the influenza virus M2 protein (M2e) as the target antigen and constructed two optimized M2e DNA vaccines (p-tPA-p3M2e and p-p3M2e) with increased antigenic epitope density and enhanced antigen secretion. Both vaccines induced high M2e-specific humoral and cellular immune responses in the vaccinated mice. These two vaccines also conferred protection against a lethal infection of homo-subtypic H1N1 virus, with p-tPA-p3M2e being the most effective. In addition, p-tPA-p3M2e also showed cross-protection against different subtypes of the influenza virus (H9N2, H6N6, and H10N8) at varying rates (80%, 40%, and 20%, respectively). After passive immunization, M2e DNA vaccine-induced antibodies in the sera provided complete protection against homologous virus challenge. An analysis of the mechanism underlying this immunization-mediated protection indicates that M2e-specific IgG and T-cell immune responses may play critical roles in the prevention of infection and viral clearance. Taken together, our results indicate that this optimized M2e DNA vaccine is a promising candidate for the development of a universal, broad-spectrum influenza virus vaccine.

negative: Antigen Sparing and Enhanced Protection Using A Novel rOv-ASP-1 Adjuvant in Aqueous Formulation with Influenza Vaccines Influenza is one of the most common infectious diseases endangering the health of humans, especially young children and the elderly. Although vaccination is the most effective means of protection against influenza, frequent mutations in viral surface antigens, low protective efficacy of the influenza vaccine in the elderly, slow production process and the potential of vaccine supply shortage during a pandemic are significant limitations of current vaccines. Adjuvants have been used to enhance the efficacy of a variety of vaccines; however, no adjuvant is included in current influenza vaccines approved in the United States. In this study, we found that a novel adjuvant, rOv-ASP-1, co-administrated with inactivated influenza vaccine using an aqueous formulation, substantially improved the influenza-specific antibody response and protection against lethal infection in a mouse model. rOv-ASP-1 enhanced the magnitude of the specific antibody response after immunization with low doses of influenza vaccine, allowing antigen-sparring by 10-fold. The rOv-ASP-1 formulated vaccine induced a more rapid response and a stronger Th1-associated antibody response compared to vaccine alone and to the vaccine formulated with the adjuvant alum. Importantly, rOv-ASP-1 significantly enhanced cross-reactive antibody responses and protection against challenge with an antigenically distinct strain. These results demonstrate that rOv-ASP-1 is an effective adjuvant that: 1) accelerates and enhances the specific antibody response induced by influenza vaccine; 2) allows for antigen sparing; and 3) augments a Th1-biased and cross-reactive antibody response that confers protection against an antigenically distinct strain.

negative: The immunologic status of newborns born to SARS-CoV2-infected mothers in Wuhan, China Background Immunologic dysfunction due to COVID-19 is closely related to clinical prognosis, and the inflammatory response of pregnant women may affect the directional differentiation and function of fetal immune cells. Objective To analyze the immune status of newborns from mothers with COVID-19 in the third trimester. Methods Along with collecting the clinical data from 51 newborns and their respective mothers, we also recorded the immunophenotypes and cytokine and immunoglobulin levels of the newborns. Results None of the 51 newborns showed fever or respiratory distress during hospitalization. Detection of SARS-CoV-2 nucleic acid in pharyngeal swabs was negative. Except for the low level of CD16-CD56 cells, the count and proportion of lymphocytes, CD3, CD4, CD8, and CD19 were all in the normal range. Moreover, the serum IgG and IgM levels were within the normal range, while IL-6 showed increased levels. There was no correlation between maternal COVID-19 duration and the lymphocyte subsets or cytokine levels (IFN-γ, IL-2, IL-4, IL-6, IL-10 and TNF-α). There was a positive correlation between IL-6 and IL-10 levels and CD16-CD56 cells. One (1.96%) infant with an extremely elevated IL-6 concentration developed necrotizing enterocolitis in the third week after birth, and the remaining 50 infants did not show abnormal symptoms through the end of the follow-up period. Conclusion COVID-19 in the third trimester did not significantly affect the cellular and humoral immunity of the fetus, and there was no evidence that the differentiation of lymphocyte subsets was seriously unbalanced.

negative: Significant Relaxation of SARS-CoV-2-Targeted Non-Pharmaceutical Interventions Will Result in Profound Mortality: A New York State Modelling Study Severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) is the most significant global health crisis of the 21(st) century. The aim of this study was to develop a model to estimate the effect of undocumented infections, seasonal infectivity, immunity, and non-pharmaceutical interventions (NPIs), such as social distancing, on the transmission, morbidity, and mortality of SARS-CoV-2 in New York State (NYS). Simulations revealed dramatic infectivity driven by undocumented infections, and a peak basic reproductive number in NYS of 5.7. NPIs have been effective, and relaxation >50% will result in tens-of-thousands more deaths. Endemic infection is likely to occur in the absence of profound sustained immunity. As a result, until an effective vaccine or other effective pharmaceutical intervention is developed, it will be critical to not reduce NPIs >50% below current levels. This study establishes fundamental characteristics of SARS-CoV-2 transmission, which can help policymakers navigate combating this virus in the coming years.

negative: Consistent Detection of 2019 Novel Coronavirus in Saliva The 2019 novel coronavirus (2019-nCoV) was detected in the self-collected saliva of 91.7% (11/12) of patients. Serial saliva viral load monitoring generally showed a declining trend. Live virus was detected in saliva by viral culture. Saliva is a promising noninvasive specimen for diagnosis, monitoring, and infection control in patients with 2019-nCoV infection.

negative: Current progress in the development of a prophylactic vaccine for HIV-1 Since its discovery and characterization in the early 1980s as a virus that attacks the immune system, there has been some success for the treatment of human immunodeficiency virus-1 (HIV-1) infection. However, due to the overwhelming public health impact of this virus, a vaccine is needed urgently. Despite the tireless efforts of scientist and clinicians, there is still no safe and effective vaccine that provides sterilizing immunity. A vaccine that provides sterilizing immunity against HIV infection remains elusive in part due to the following reasons: 1) degree of diversity of the virus, 2) ability of the virus to evade the hosts’ immunity, and 3) lack of appropriate animal models in which to test vaccine candidates. There have been several attempts to stimulate the immune system to provide protection against HIV-infection. Here, we will discuss attempts that have been made to induce sterilizing immunity, including traditional vaccination attempts, induction of broadly neutralizing antibody production, DNA vaccines, and use of viral vectors. Some of these attempts show promise pending continued research efforts.

negative: Use of Hydroxychloroquine and Chloroquine During the COVID-19 Pandemic: What Every Clinician Should Know Two medications often used for treatment of immune-mediated conditions, hydroxychloroquine and chloroquine, have recently attracted widespread interest as potential therapies for coronavirus disease 2019. The authors of this commentary provide guidance for clinical decision making for patients with coronavirus disease 2019 as well as for patients with rheumatologic conditions, such as systemic lupus erythematosus and rheumatoid arthritis

negative: Impact of Preexisting Adenovirus Vector Immunity on Immunogenicity and Protection Conferred with an Adenovirus-Based H5N1 Influenza Vaccine The prevalence of preexisting immunity to adenoviruses in the majority of the human population might adversely impact the development of adaptive immune responses against adenovirus vector-based vaccines. To address this issue, we primed BALB/c mice either intranasally (i.n.) or intramuscularly (i.m.) with varying doses of wild type (WT) human adenovirus subtype 5 (HAd5). Following the development of immunity against HAd5, we immunized animals via the i.n. or i.m. route of inoculation with a HAd vector (HAd-HA-NP) expressing the hemagglutinin (HA) and nucleoprotein (NP) of A/Vietnam/1203/04 (H5N1) influenza virus. The immunogenicity and protection results suggest that low levels of vector immunity (<520 virus-neutralization titer) induced by priming mice with up to 10(7) plaque forming units (p.f.u.) of HAd-WT did not adversely impact the protective efficacy of the vaccine. Furthermore, high levels of vector immunity (approximately 1500 virus-neutralization titer) induced by priming mice with 10(8) p.f.u. of HAd-WT were overcome by either increasing the vaccine dose or using alternate routes of vaccination. A further increase in the priming dose to 10(9) p.f.u. allowed only partial protection. These results suggest possible strategies to overcome the variable levels of human immunity against adenoviruses, leading to better utilization of HAd vector-based vaccines.

negative: Advances in disease diagnosis, vaccine development and other emerging methods to control pathogens in aquaculture Disease is still regarded as a major constraint to aquaculture production globally. Rapid disease diagnosis and vaccination play a huge part in the control of bacterial diseases, and there has been significant progress in both of these areas. This chapter considers the limitations of existing methods and reviews recent advances made in pathogen detection technologies and vaccine development methodologies. Future directions are discussed, including nanotechnology and reversed vaccinology.

negative: Non-specific Effect of Vaccines: Immediate Protection against Respiratory Syncytial Virus Infection by a Live Attenuated Influenza Vaccine The non-specific effects (NSEs) of vaccines have been discussed for their potential long-term beneficial effects beyond direct protection against a specific pathogen. Cold-adapted, live attenuated influenza vaccine (CAIV) induces local innate immune responses that provide a broad range of antiviral immunity. Herein, we examined whether X-31ca, a donor virus for CAIVs, provides non-specific cross-protection against respiratory syncytial virus (RSV). The degree of RSV replication was significantly reduced when X-31ca was administered before RSV infection without any RSV-specific antibody responses. The vaccination induced an immediate release of cytokines and infiltration of leukocytes into the respiratory tract, moderating the immune perturbation caused by RSV infection. The potency of protection against RSV challenge was significantly reduced in TLR3(-/-) TLR7(-/-) mice, confirming that the TLR3/7 signaling pathways are necessary for the observed immediate and short-term protection. The results suggest that CAIVs provide short-term, non-specific protection against genetically unrelated respiratory pathogens. The additional benefits of CAIVs in mitigating acute respiratory infections for which vaccines are not yet available need to be assessed in future studies.

negative: Type I astrocytes and microglia induce a cytokine response in an encephalitic murine coronavirus infection The pathogenesis of viral infections involves an immune response by cytokines, causing a deleterious effect on organ function, in addition to tissue destruction due to viral replication. Clinical symptoms and laboratory findings of the human coronavirus disease COVID-19, caused by the novel coronavirus SARS CoV-2, indicate cytokine involvement. Our laboratory showed that an experimental murine coronavirus (MHV-A59) can be transmitted into the brain by intranasal or intracerebral exposure and that neurovirulence is mediated by cytokine secretion. In this study we investigated which cells in the brain produce cytokines, thus functioning as the brain's innate immune system. Using tissue cultures of microglia, and clonal populations of astrocytes, we found that microglia and type I astrocytes (but not types II and III), produced pro-inflammatory cytokines in response to MHV-A59 infection. A molecularly closely related, non-encephalitic strain of the virus (MHV-2) caused in vitro infection, but without cytokine induction. Furthermore, immunofluorescence and immunohistochemistry revealed that type I astrocytes and microglia have perivascular foot processes necessary for the formation of the perivascular glymphatic system, the anatomical site of the brain's innate immune system. Cytokine secretion by type I astrocytes and microglia, as part of the brain's glymphatic and innate immune system, contributes to the pathogenesis of an encephalitic coronavirus infection, and indicates the rationale for anti-cytokine therapies for COVID-19.

negative: Structural analysis of SARS-CoV-2 and predictions of the human interactome Specific elements of viral genomes regulate interactions within host cells. Here, we calculated the secondary structure content of >2500 coronaviruses and computed >100000 human protein interactions with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We found that the 3’ and 5’ are the most structured elements in the viral genome and the 5’ has the strongest propensity to associate with human proteins. The domain encompassing nucleotides 23000 – 24000 is highly conserved both at the sequence and structural level, while the region upstream varies significantly. These two sequences code for a domain of the viral protein Spike S that interacts with the human receptor angiotensin-converting enzyme 2 (ACE2) and has the potential to bind sialic acids. Our predictions indicate that the first 1000 nucleotides in the 5’ can interact with proteins involved in viral RNA processing such as double-stranded RNA specific editases and ATP-dependent RNA-helicases, in addition to other high-confidence candidate partners. These interactions, previously reported to be also implicated in HIV, reveal important information on hostvirus interactions. The list of transcriptional and post-transcriptional elements recruited by SARS-CoV-2 genome provides clues on the biological pathways associated with gene expression changes in human cells.

negative: Phylogenetic Analysis of the Novel Coronavirus Reveals Important Variants in Indian Strains Recently classified as a pandemic by WHO, novel Corononavirus 2019 has affected almost every corner of the globe causing human deaths in a range of hundred thousands. The virus having its roots in Wuhan (China) has been spread over the world by its own property to change itself accordingly. These changes correspond to its transmission and pathogenicity due to which the concept of social distancing appeared into the picture. In this paper, a few findings from the whole genome sequence analysis of viral genome sequences submitted from India are presented. The data used for analysis comprises 440 collective genome sequences of virus submitted in GenBank, GISAID, and SRA projects, from around the world as well as 28 viral sequences from India. Multiple sequence alignment of all genome sequences was performed and analysed. A novel non-synonymous mutation 4809C>T (S1515F) in NSP3 gene of SARS-CoV2 Indian strains is reported along with other frequent and important changes from around the world: 3037C>T, 14408C>T, and 23403A>G. The novel change was observed in samples collected in the month of March, whereas was found to be absent in samples collected in January with the respective persons’ travel history to China. Phylogenetic analysis clustered the sequences with this change as one separate clade. Mutation was predicted as stabilising change by insilco tool DynaMut. A second patient in the world to our knowledge with multiple (Wuhan and USA) strain contraction was observed in this study. The infected person is among the two early infected patients with travel history to China. Strains sequenced in Iran stood out to have different variants, as most of the reported frequent variants were not observed. The objective of this paper is to highlight the similarities and changes observed in the submitted Indian viral strains. This helps to keep track on the activity, that how virus is changing into a new subtype. Major strains observed were European with the novel change in India and other being emergent clade of Iran. Its important to observe the changes in NSP3 gene, as this gene has been reported with extensive positive selection as well as potential drug target. Extensive Positive Selection Drives the Evolution of Nonstructural Proteins. With the limited number of sequences this was the only frequent novel non-synonymous change observed from Indian strains, thereby making this change vulnerable for investigation in future. This paper has a special focus on tracking of Indian viral sequences submitted in public domain.

negative: Toning down the 2019-nCoV media hype—and restoring hope

negative: A highly conserved cryptic epitope in the receptor-binding domains of SARS-CoV-2 and SARS-CoV The outbreak of COVID-19, which is caused by SARS-CoV-2 virus, continues to spread globally, but there is currently very little understanding of the epitopes on the virus. In this study, we have determined the crystal structure of the receptor-binding domain (RBD) of the SARS-CoV-2 spike (S) protein in complex with CR3022, a neutralizing antibody previously isolated from a convalescent SARS patient. CR3022 targets a highly conserved epitope that enables cross-reactive binding between SARS-CoV-2 and SARS-CoV. Structural modeling further demonstrates that the binding site can only be accessed when at least two RBDs on the trimeric S protein are in the “up” conformation. Overall, this study provides structural and molecular insight into the antigenicity of SARS-CoV-2. ONE SENTENCE SUMMARY Structural study of a cross-reactive SARS antibody reveals a conserved epitope on the SARS-CoV-2 receptor-binding domain.

negative: Deducing the N- and O- glycosylation profile of the spike protein of novel coronavirus SARS-CoV-2 The current emergence of the novel coronavirus pandemic caused by SARS-CoV-2 demands the development of new therapeutic strategies to prevent rapid progress of mortalities. The coronavirus spike (S) protein, which facilitates viral attachment, entry and membrane fusion is heavily glycosylated and plays a critical role in the elicitation of the host immune response. The spike protein is comprised of two protein subunits (S1 and S2), which together possess 22 potential N-glycosylation sites. Herein, we report the glycosylation mapping on spike protein subunits S1 and S2 expressed on human cells through high resolution mass spectrometry. We have characterized the quantitative N-glycosylation profile on spike protein and interestingly, observed unexpected O-glycosylation modifications on the receptor binding domain (RBD) of spike protein subunit S1. Even though O-glycosylation has been predicted on the spike protein of SARS-CoV-2, this is the first report of experimental data for both the site of O-glycosylation and identity of the O-glycans attached on the subunit S1. Our data on the N- and O-glycosylation is strengthened by extensive manual interpretation of each glycopeptide spectra in addition to using bioinformatics tools to confirm the complexity of glycosylation in the spike protein. The elucidation of the glycan repertoire on the spike protein provides insights into the viral binding studies and more importantly, propels research towards the development of a suitable vaccine candidate.

negative: Why are vaccines against many human viral diseases still unavailable; an historic perspective? The number of new and improved human viral vaccines licensed in recent years contrasts sharply with what could be termed the golden era (1955‐1990) when vaccines against polio‐, measles, mumps, rubella, and hepatitis B viruses first became available. Here, we attempt to explain why vaccines, mainly against viruses other than human immunodeficiency virus and hepatitis C virus, are still unavailable. They include human herpesviruses other than varicella‐zoster virus, respiratory syncytial and most other respiratory, enteric and arthropod‐borne viruses. Improved oral poliovirus vaccines are also urgently required. Their unavailability is attributable to regulatory/economic factors and the properties of individual viruses, but also to an absence of relevant animal models and ethical problems for the conduct of clinical of trials in pediatric and other critical populations. All are portents of likely difficulties for the licensing of effective vaccines against emerging pathogens, such as avian influenza, Ebola, and Zika viruses.

negative: Emerging viruses and current strategies for vaccine intervention During the past decade several notable viruses have suddenly emerged from obscurity or anonymity to become serious global health threats, provoking concern regarding their sustained epidemic transmission in immunologically naive human populations. With each new threat comes the call for rapid vaccine development. Indeed, vaccines are considered a critical component of disease prevention for emerging viral infections because, in many cases, other medical options are limited or non‐existent, or that infections result in such a rapid clinical deterioration that the effectiveness of therapeutics is limited. While classic approaches to vaccine development are still amenable to emerging viruses, the application of molecular techniques in virology has profoundly influenced our understanding of virus biology, and vaccination methods based on replicating, attenuated and non‐replicating virus vector approaches have become useful vaccine platforms. Together with a growing understanding of viral disease emergence, a range of vaccine strategies and international commitment to underpin development, vaccine intervention for new and emerging viruses may become a possibility.

negative: The Coronavirus PEDV Evades Type III Interferon Response Through the miR-30c-5p/SOCS1 Axis Porcine epidemic diarrhea virus (PEDV) is an economically important pathogen that has evolved several mechanisms to evade type I IFN responses. Type III interferon (IFN-λ), an innate cytokine that primarily targets the mucosal epithelia, is critical in fighting mucosal infection in the host and has been reported to potently inhibit PEDV infection in vitro. However, how PEDV escapes IFN-λ antiviral response remains unclear. In this study, we found that PEDV infection induced significant IFN-λ expression in type I IFN-defective Vero E6 cells, but virus-induced endogenous IFN-λ did not reduce PEDV titers. Moreover, we demonstrated that PEDV escaped IFN-λ responses by substantially upregulating the suppressor of cytokine signaling protein 1 (SOCS1) expression, which impaired the induction of IFN-stimulated genes (ISGs) and dampened the IFN-λ antiviral response and facilitated PEDV replication in Vero E6 cells. We further showed that PEDV infection increased SOCS1 expression by decreasing host miR-30c-5p expression. MiR-30c-5p suppressed SOCS1 expression through targeting the 3′ untranslated region (UTR) of SOCS1. The inhibition of IFN-λ elicited ISGs expression by SOCS1 was specifically rescued by overexpression of miR-30c-5p. Collectively, our findings identify a new strategy by PEDV to escape IFN-λ-mediated antiviral immune responses by engaging the SOCS1/miR-30c axis, thus improving our understanding of its pathogenesis.

negative: The effect of adjuvants on vaccine-induced antibody response against influenza in aged mice While influenza remains a major threat to public health, researchers continue to search for a universal solution to improving the efficacy of the influenza vaccine. Even though influenza affects people of all different ages, it can be extremely hazardous to people of 65 years of age or older since that is the population that makes up the high majority of the death toll caused by influenza-related diseases. Elderly individuals suffer the effects of immunosenescence as they age, which is the diminishing of the overall immune response. Immunosenescence occurs by specifically affecting the adaptive immune response which controls the establishment of immunity after vaccination or infection. There are many studies under way that are trying to find a resolution to the problem of the influenza vaccine not providing enough protection in the elderly population. One of the possible strategies is to seek the use of an optimal adjuvant, an immunological agent that can enhance immune responses, with the current vaccine formulation. Here, we used the murine model to review the effects of adjuvants on the antibody response to influenza vaccines in aged mice. Since adjuvants can enhance the production of important inflammatory cytokines and activation of dendritic cells, the stimulation of these cells are boosted to increase the effectiveness of the influenza vaccine in aged mice which would hopefully translate to the elderly.

negative: Exit through the App Store? This Preview summarizes the Ada Lovelace Institute rapid evidence review Exit through the App Store?, which sets out proposals for whether, and how, the UK government should use technology to transition from the COVID-19 global public health crisis. It examines the potential development and implementation of technical solutions to support symptom tracking, contact tracing, and immunity certification. The full rapid evidence review takes into account societal, political, legal, and ethical perspectives and gives findings and recommendations for the transition and rebuild phases that follow containment, delay, and mitigation.

negative: Emerging Trends in COVID-19 Treatment: Learning from Inflammatory Conditions Associated with Cellular Therapies Coronavirus disease 2019 (SARS-CoV2) is an active global health threat for which treatments are desperately being sought. Even though most people infected experience mild to moderate respiratory symptoms and recover with supportive care, certain vulnerable hosts develop severe clinical deterioration. While several drugs are currently being investigated in clinical trials, there are currently no approved treatments or vaccines for COVID-19 and hence there is an unmet need to explore additional therapeutic options. At least three inflammatory disorders or syndromes associated with immune dysfunction have been described in the context of cellular therapy. Specifically, Cytokine Release Syndrome (CRS), Immune Reconstitution Inflammatory Syndrome (IRIS), and Secondary Hemophagocytic Lymphohistiocytosis (sHLH) all have clinical and laboratory characteristics in common with COVID19 and associated therapies that could be worth testing in the context of clinical trials. Here we discuss these diseases, their management, and potential applications of these treatment in the context of COVID-19. We also discuss current cellular therapies that are being evaluated for the treatment of COVID-19 and/or its associated symptoms.

negative: RNA sequencing-based analysis of the spleen transcriptome following infectious bronchitis virus infection of chickens selected for different mannose-binding lectin serum concentrations BACKGROUND: Avian infectious bronchitis is a highly contagious disease of the upper-respiratory tract caused by infectious bronchitis virus (IBV). Understanding the molecular mechanisms involved in the interaction between innate and adaptive immune responses to IBV infection is a crucial element for further improvements in strategies to control IB. To this end, two chicken lines, selected for high (L10H line) and low (L10L line) serum concentration of mannose-binding lectin (MBL) were studied. In total, 32 birds from each line were used. Sixteen birds from each line were infected with IBV and sixteen were left uninfected. Eight uninfected and infected birds from each line were euthanized at 1 and 3 weeks post infection. RNA sequencing was performed on spleen samples from all 64 birds and differential gene expression analysis was performed for four comparisons: L10L line versus L10H line for uninfected birds at weeks 1 and 3, respectively, and in the same way for infected birds. Functional analysis was performed using Gene Ontology (GO) Immune System Process terms specific for Gallus gallus. RESULTS: Comparing uninfected L10H and L10L birds, we identified 1698 and 1424 differentially expressed (DE) genes at weeks 1 and 3, respectively. For the IBV-infected birds, 1934 and 866 DE genes were identified between the two lines at weeks 1 and 3, respectively. The two most enriched GO terms emerging from the comparison of uninfected birds between the two lines were “Lymphocyte activation involved in immune response” and “Somatic recombination of immunoglobulin genes involved in immune response” at weeks 1 and 3, respectively. When comparing IBV-infected birds between the two lines, the most enriched GO terms were “Alpha-beta T cell activation” and “Positive regulation of leukocyte activation” at weeks 1 and 3, respectively. CONCLUSIONS: Healthy birds from the two lines showed significant differences in expression profiles for subsets of adaptive and innate immunity-related genes, whereas comparison of the IBV-infected birds from the two lines showed differences in expression of immunity-related genes involved in T cell activation and proliferation. The observed transcriptome differences between the two lines indicate that selection for MBL had influenced innate as well as adaptive immunity. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12864-016-2403-1) contains supplementary material, which is available to authorized users.

negative: SARS-CoV2 drives JAK1/2-dependent local and systemic complement hyper-activation Patients with coronavirus disease 2019 (COVID-19) present with a range of devastating acute clinical manifestations affecting the lungs, liver, kidneys and gut. The best-characterized entry receptor for the disease-causing virus SARS-CoV2, angiotensin converting enzyme (ACE) 2, is highly expressed in these tissues. However, the pathways that underlie the disease are still poorly understood. Here we show that the complement system is unexpectedly one of the intracellular pathways most highly induced by SARS-CoV2 infection in lung epithelial and liver cells. Within cells of the bronchoalveolar lavage of patients, distinct signatures of complement activation in myeloid, lymphoid and epithelial cells tracked with disease severity. Modelling the regulome of host genes induced by COVID-19 and the drugs that could normalize these genes both implicated the JAK1/2-STAT1 signaling system downstream of type I interferon receptors, and NF-kB. Ruxolitinib, a JAK1/2 inhibitor and the top predicted pharmaceutical candidate, normalized interferon signature genes, IL-6 (the best characterized severity marker in COVID-19) and all complement genes induced by SARS-CoV2, but did not affect NF-kB-regulated genes. We predict that combination therapy with JAK inhibitors and other agents with the potential to normalize NF-kB-signaling, such as anti-viral agents, may serve as an effective clinical strategy.

negative: Comment on “Should COVID-19 Concern Nephrologists? Why and to What Extent? The Emerging Impasse of Angiotensin Blockade”

negative: Evidence Supporting Transmission of Severe Acute Respiratory Syndrome Coronavirus 2 While Presymptomatic or Asymptomatic Recent epidemiologic, virologic, and modeling reports support the possibility of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission from persons who are presymptomatic (SARS-CoV-2 detected before symptom onset) or asymptomatic (SARS-CoV-2 detected but symptoms never develop). SARS-CoV-2 transmission in the absence of symptoms reinforces the value of measures that prevent the spread of SARS-CoV-2 by infected persons who may not exhibit illness despite being infectious. Critical knowledge gaps include the relative incidence of asymptomatic and symptomatic SARS-CoV-2 infection, the public health interventions that prevent asymptomatic transmission, and the question of whether asymptomatic SARS-CoV-2 infection confers protective immunity.

negative: A dissection of SARS-CoV2 with clinical implications (Review) We are being confronted with the most consequential pandemic since the Spanish flu of 1918-1920 to the extent that never before have 4 billion people quarantined simultaneously; to address this global challenge we bring to the forefront the options for medical treatment and summarize SARS-CoV2 structure and functions, immune responses and known treatments. Based on literature and our own experience we propose new interventions, including the use of amiodarone, simvastatin, pioglitazone and curcumin. In mild infections (sore throat, cough) we advocate prompt local treatment for the naso-pharynx (inhalations; aerosols; nebulizers); for moderate to severe infections we propose a tried-and-true treatment: the combination of arginine and ascorbate, administered orally or intravenously. The material is organized in three sections: i) Clinical aspects of COVID-19; acute respiratory distress syndrome (ARDS); known treatments; ii) Structure and functions of SARS-CoV2 and proposed antiviral drugs; iii) The combination of arginine-ascorbate.

negative: Infektionsschutz und spezielle Hygienemaßnahmen in klinischen Disziplinen

negative: MERS-CoV spike protein: Targets for vaccines and therapeutics Abstract The disease outbreak caused by Middle East respiratory syndrome coronavirus (MERS-CoV) is still ongoing in the Middle East. Over 1700 people have been infected since it was first reported in September 2012. Despite great efforts, licensed vaccines or therapeutics against MERS-CoV remain unavailable. The MERS-CoV spike (S) protein is an important viral antigen known to mediate host-receptor binding and virus entry, as well as induce robust humoral and cell-mediated responses in humans during infection. In this review, we highlight the importance of the S protein in the MERS-CoV life cycle, summarize recent advances in the development of vaccines and therapeutics based on the S protein, and discuss strategies that can be explored to develop new medical countermeasures against MERS-CoV.

negative: Letter to the Editor ”The Battle of Humans and COVID-19: A War without Smoke”

negative: The cross-sectional study of hospitalized coronavirus disease 2019 patients in Xiangyang, Hubei province Summary Objective To describe the epidemiological and clinical characteristics of the Coronavirus Disease 2019 (COVID-19) hospitalized patients and to offer suggestions to the urgent needs of COVID-19 prevention, diagnosis and treatment. Methods We included 102 confirmed COVID-19 cases hospitalized in Xiangyang No.1 peoples hospital, Hubei, China until Feb 9th, 2020. Demographic data, laboratory findings and chest computed tomographic (CT) images were obtained and analyzed. Findings All cases were confirmed by real-time RT-PCR, including 52 males and 50 females with a mean age of 50.38 years (SD 16.86). Incubation time ranged from one to twenty days with a mean period of 8.09 days (SD 4.99). Fever (86[84.3%] of 102 patients), cough (58[57%]), fatigue (28[27%]), shortness of breath (24[23%]), diarrhea (15[15%]), expectoration (13[12%]), inappetence (11[10%]) were common clinical manifestations. We observed a decreased blood leukocyte count and lymphopenia in 21 (20.6%) and 56 (54.9%) patients, respectively. There were 66 (68%) of 97 patients with elevated C-reactive protein levels and 49 (57.6%) of 85 with increased erythrocytes sedimentation rate. Higher levels of procalcitonin and ferritin were observed in 19 (25.3%) of 75 and 12 (92.3%) of 13 patients, respectively. Eight patients were admitted to intensive care unit (ICU), six developed respiratory failure, three had multiple organ failure and three died. The cumulative positivity rate over three rounds of real-time RT-PCR was 96%. One-hundred patients were found with typical radiological abnormalities in two rounds of chest CT scans, indicating a 98% consistency with real-time RT-PCR results. Interpretation Most COVID-19 patients in Xiangyang were secondary cases without sex difference, and the rate of severe cases and death was low. Middle-to-old-age individuals were more susceptible to the virus infection and the subsequent development of severe/fatal consequences. The average incubation period was longer among our patients. We recommend prolonging the quarantine period to three weeks. Three times real-time RT-PCR plus two times CT scans is a practical clinical diagnosis strategy at present and should be used to increase the accuracy of diagnosis, thereby controlling the source of infection more effectively. Key Words SARS-CoV-2; COVID-19; epidemiological and clinical features; diagnosis

negative: Potential Neutralizing Antibodies Discovered for Novel Corona Virus Using Machine Learning The fast and untraceable virus mutations take lives of thousands of people before the immune system can produce the inhibitory antibody. Recent outbreak of novel coronavirus infected and killed thousands of people in the world. Rapid methods in finding peptides or antibody sequences that can inhibit the viral epitopes of COVID-19 will save the life of thousands. In this paper, we devised a machine learning (ML) model to predict the possible inhibitory synthetic antibodies for Corona virus. We collected 1933 virus-antibody sequences and their clinical patient neutralization response and trained an ML model to predict the antibody response. Using graph featurization with variety of ML methods, we screened thousands of hypothetical antibody sequences and found 8 stable antibodies that potentially inhibit COVID-19. We combined bioinformatics, structural biology, and Molecular Dynamics (MD) simulations to verify the stability of the candidate antibodies that can inhibit the Corona virus.

negative: Crushing the curve, the role of national and international institutions and policy makers in COVID-19 pandemic Nobody can be fully prepared to a pandemic. Of course there are signs of it, the scientists can predict, alarming speeches can be made. But there are always alarmist people around, maybe that is why sometimes even the most serious warnings may be not considered by the authorities on time. The first patients may be lost without a proper diagnosis. When everybody realizes that there may be a big problem in the horizon, sometimes it is too late. That is why it is very important to monitor contagious diseases and follow the warnings and releases of national and international disease control centers and other related organizations. China celebrated Lunar New Year with more than 40 thousand families on the 18 of January 2020. Nobody seem to be expecting this emerging new viral pneumonia outbreak appeared in Wuhan, in the last days of 2019, will break the chains and turn out to be a pandemic! But maybe this time it was not too late. There were four important pandemics within the last century: Spanish Flu, Hong Kong Flu, Asian Flu and Swine Flu. Each left different story behind. Millions of people had infected, hundreds, thousands of people died. This time, the Modern World had different tools to limit the SARS CoV2 outbreak. The national and international institutions of our globe were all communicating and taking precautions in a very fast manner than ever. However, this time, unexpectedly, the SARS-CoV-2 contagion was also faster. Besides the international organizations like WHO, UNESCO and UNICEF, the roles of local authorities, health ministries, disease control centers, health protection agencies, research centers and universities are all very important in different operational levels to control and survive from the pandemic. This paper will review the immediate response of different national and international institutions and authorities to COVID-19 pandemic.

negative: SARS-CoV2: should inhibitors of the renin–angiotensin system be withdrawn in patients with COVID-19?

negative: Avian Infectious Bronchitis Virus Avian infectious bronchitis (IB) is caused by avian infectious bronchitis virus (IBV) belonging to Coronaviridae family. The disease is prevalent in all countries with almost 100% incidence rate. Chicken and commercially reared pheasant are the natural host for IBV. Virus causes respiratory diseases, poor weight gain, feed efficiency in broiler, damage to oviduct, and abnormal egg production in mature hens resulting in economic losses. IBV also replicates in tracheal and renal epithelial cells leading to prominent tracheal and kidney lesions. Virus undergoes spontaneous mutation leading to continual emergence of new variants. The effectiveness of immunization program is diminished because of poor cross-protection among the serotypes. Identification of circulating serotypes is important in controlling IBV infection. Toll-like receptor 3 (TLR3) and TLR21 are involved in early recognition of virus resulting in induction of inflammatory cytokines. Both humoral and cellular immune responses are important in the control of infection. Humoral immunity plays an important role in recovery and clearance of viral infection. IBV-specific cytotoxic T lymphocytes induce lysis of IBV-infected cells. Effective diagnostic tools are required at field level to identify different IBV variants. Embryonated chicken eggs are effective model for virus isolation. Identification by other specific methods like virus neutralization (VN), hemagglutination inhibition (HI), enzyme linked immunosorbent assay (ELISA), immunohistochemistry, or nucleic acid analysis or by electron microscopy is also indispensable. VN test in tracheal organ culture is the best method for antigenic typing for surveillance purposes. Continuous epidemiological surveillance, strict biosecurity measures, and vaccine effective against various serotypes are necessary for controlling IB in chickens.

negative: The potential use of social media and other internet-related data and communications for child maltreatment surveillance and epidemiological research: Scoping review and recommendations Abstract Collecting child maltreatment data is a complicated undertaking for many reasons. As a result, there is an interest by child maltreatment researchers to develop methodologies that allow for the triangulation of data sources. To better understand how social media and internet-based technologies could contribute to these approaches, we conducted a scoping review to provide an overview of social media and internet-based methodologies for health research, to report results of evaluation and validation research on these methods, and to highlight studies with potential relevance to child maltreatment research and surveillance. Many approaches were identified in the broad health literature; however, there has been limited application of these approaches to child maltreatment. The most common use was recruiting participants or engaging existing participants using online methods. From the broad health literature, social media and internet-based approaches to surveillance and epidemiologic research appear promising. Many of the approaches are relatively low cost and easy to implement without extensive infrastructure, but there are also a range of limitations for each method. Several methods have a mixed record of validation and sources of error in estimation are not yet understood or predictable. In addition to the problems relevant to other health outcomes, child maltreatment researchers face additional challenges, including the complex ethical issues associated with both internet-based and child maltreatment research. If these issues are adequately addressed, social media and internet-based technologies may be a promising approach to reducing some of the limitations in existing child maltreatment data.

negative: Guidelines for pregnant women with suspected SARS-CoV-2 infection

negative: Virus-Vectored Ebola Vaccines The Ebola virus disease (EVD) is one of the most dangerous infections affecting humans and animals. The first EVD outbreaks occurred in 1976 in Sudan and Zaire. Since then, more than 20 outbreaks have occurred; the largest of which (2014−2016) evolved into an epidemic in West Africa and claimed the lives of more than 11,000 people. Although vaccination is the most effective way to prevent epidemics, there was no licensed vaccine for EVD at the beginning of the latest outbreak. The development of the first vaccines for EVD started in 1980 and has come a long technological way, from inactivated to genetically engineered vaccines based on recombinant viral vectors. This review focuses on virus-vectored Ebola vaccines that have demonstrated the greatest efficacy in preclinical trials and are currently under different phases of clinical trial. Particular attention is paid to the mechanisms of immune response development, which are important for protection from EVD, and the key vaccine parameters necessary for inducing long-term protective immunity against EVD.

negative: Do chronic respiratory diseases or their treatment affect the risk of SARS-CoV-2 infection?

negative: Robust neutralization assay based on SARS-CoV-2 S-bearing vesicular stomatitis virus (VSV) pseudovirus and ACE2-overexpressed BHK21 cells The global pandemic of Coronavirus disease 2019 (COVID-19) is a disaster for human society. A convenient and reliable in vitro neutralization assay is very important for the development of neutralizing antibodies, vaccines and other inhibitors. In this study, G protein-deficient vesicular stomatitis virus (VSVdG) bearing full-length and truncated spike (S) protein of SARS-CoV-2 were evaluated. The virus packaging efficiency of VSV-SARS-CoV-2-Sdel18 (S with C-terminal 18 amino acid truncation) is much higher than VSV-SARS-CoV-2-S. A neutralization assay for antibody screening and serum neutralizing titer quantification was established based on VSV-SARS-CoV-2-Sdel18 pseudovirus and human angiotensin-converting enzyme 2 (ACE2) overexpressed BHK21 cell (BHK21-hACE2). The experimental results can be obtained by automatically counting EGFP positive cell number at 12 hours after infection, making the assay convenient and high-throughput. The serum neutralizing titer of COVID-19 convalescent patients measured by VSV-SARS-CoV-2-Sdel18 pseudovirus assay has a good correlation with live SARS-CoV-2 assay. Seven neutralizing monoclonal antibodies targeting receptor binding domain (RBD) of SARS-CoV-2-S were obtained. This efficient and reliable pseudovirus assay model could facilitate the development of new drugs and vaccines.

negative: Evidence of the Recombinant Origin and Ongoing Mutations in Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) The recent global outbreak of viral pneumonia designated as Coronavirus Disease 2019 (COVID-19) by coronavirus (SARS-CoV-2) has threatened global public health and urged to investigate its source. Whole genome analysis of SARS-CoV-2 revealed ~96% genomic similarity with bat CoV (RaTG13) and clustered together in phylogenetic tree. Furthermore, RaTGl3 also showed 97.43% spike protein similarity with SARS-CoV-2 suggesting that RaTGl3 is the closest strain. However, RBD and key amino acid residues supposed to be crucial for human-to-human and cross-species transmission are homologues between SARS-CoV-2 and pangolin CoVs. These results from our analysis suggest that SARS-CoV-2 is a recombinant virus of bat and pangolin CoVs. Moreover, this study also reports mutations in coding regions of 125 SARS-CoV-2 genomes signifying its aptitude for evolution. In short, our findings propose that homologous recombination has been occurred between bat and pangolin CoVs that triggered cross-species transmission and emergence of SARS-CoV-2, and, during the ongoing outbreak, SARS-CoV-2 is still evolving for its adaptability.

negative: Insight into COVID‐2019 for pediatricians Since December 2019, patients with unexplained pneumonia have been found in Wuhan City, Hubei Province, China. The pathogen in these cases is a new type of coronavirus. The World Health Organization confirmed this diagnosis and named the pathogen SARSCoV‐2. The disease caused by SARSCoV‐2 is called Corona Virus Disease (COVID‐2019). The virus is highly infectious and pathogenic, causing human‐to‐human transmission. At present, SARSCoV‐2 is still rampant in the world. Zhengzhou City in Henan Province serves as an example, 102 people have been confirmed to be infected with SARSCoV‐2 (at 24:00 on February 5th, 2020), including three children, the youngest is 4 years old. From the perspective of clinical pediatricians as the first line fighting the epidemic, this paper will discuss the clinical characteristics, prevention and control measures, outcomes, diagnosis, and treatment of pediatric cases.

negative: Importance of Sleep for Health and Wellbeing Amidst COVID-19 Pandemic

negative: Chapter 5 Virus Transmission and Epidemiology Abstract For transmission of a virus to occur, a virus must enter a host through a portal of entry, replicate or disseminate within the host, and be transmitted to a new host through a portal of exit. Unless delivered directly into bodily tissues through a bite or needle, most viruses interact with the epithelium at the site of entry. Localized infections replicate at the initial site of infection, while systemic infections spread to additional areas of the body. Viruses are shed into the environment most often through the same route they entered the body. The stability of virions within the environment is dependent upon virion and environmental factors. Epidemiology is the study of how diseases are transmitted through a population. Epidemiologists perform descriptive or analytic studies to characterize the chain of viral infection throughout a population and design control measures to interrupt it.

negative: Testing the repatriated for SARS-Cov2: Should laboratory-based quarantine replace traditional quarantine? Abstract Background An ongoing epidemic of respiratory diseases caused by a novel coronavirus (COVID 2019, SARS-CoV2) started in Wuhan, Hubei, in China at the end of December 2019. The French government decided to repatriate the 337 French nationals living in Wuhan and place them in quarantine in their home country. We decided to test them all for SARS-Cov2 twice in order to reduce anxiety among the population and decision-makers. Methods We investigated the presence of SARS-CoV-19 in asymptomatic carriers by testing all repatriated patients within the first 24 h of their arrival in France and at day 5. Viral RNA was extracted from pooled nasal and oropharyngeal swab fluids or sputum in the absence of nasal/oropharyngeal swabs. Detection of SARS-CoV-2 RNA was then carried out using several real-time reverse transcription (RT)-PCR assays. Results We tested 337 passengers at day 0 and day 5. All the tests for SARS-CoV2 were negative. By optimising the sampling process, sending samples sequentially and reducing the time-scale for biological analysis, we were able to test the samples within 5 h (including sampling, shipment and biological tests). Conclusion Optimising our procedures reduces anxiety and reassures the population and decision makers.

negative: Afectación clínica y sintomatológica en pacientes mayores de 65 años por COVID-19

negative: WeChat, a Chinese social media, may early detect the SARS-CoV-2 outbreak in 2019 We plotted daily data on the frequencies of keywords related to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from WeChat, a Chinese social media. Using 'Feidian', Chinese abbreviation for SARS, may detect the SARS-CoV-2 outbreak in 2019 two weeks earlier. WeChat offered a new approach to early detect disease outbreaks.

negative: Detectable serum SARS-CoV-2 viral load (RNAaemia) is closely associated with drastically elevated interleukin 6 (IL-6) level in critically ill COVID-19 patients Background: Although the SARS-CoV-2 viral load detection of respiratory specimen has been widely used for novel coronavirus disease (COVID-19) diagnosis, it is undeniable that serum SARS-CoV-2 nucleic acid (RNAaemia) could be detected in a fraction of the COVID-19 patients. However, it is not clear that if the incidence of RNAaemia could be correlated with the occurrence of cytokine storm or with the specific class of patients. Methods: This study enrolled 48 patients with COVID-19 admitted to the General Hospital of Central Theater Command, PLA, a designated hospital in Wuhan, China. The patients were divided into three groups according to the Diagnosis and Treatment of New Coronavirus Pneumonia (version 6) published by the National Health Commission of China. The clinical and laboratory data were collected. The serum viral load detection and serum IL-6 levels were determined. Except for routine statistical analysis, Generalized Linear Models (GLMs) analysis was used to establish a patient status prediction model based on real-time RT-PCR Ct value. Findings: The Result showed that cases with RNAaemia were exclusively confirmed in critically ill patients group and appeared to reflect the illness severity. Further more, the inflammatory cytokine IL-6 levels were significantly elevated in critically ill patients, which is almost 10-folds higher than those in other patients. More importantly, the extremely high IL-6 level was closely correlated with the incidence of RNAaemia (R=0.902) and the vital signs of COVID-19 patients (R= -0.682). Interpretation: Serum SARS-CoV-2 viral load (RNAaemia) is strongly associated with cytokine storm and can be used to predict the poor prognosis of COVID-19 patients. Moreover, our results strongly suggest that cytokine IL-6 should be considered as a therapeutic target in critically ill patients with excessive inflammatory response.

negative: Binding of SARS-CoV-2 and angiotensin-converting enzyme 2: clinical implications

negative: Potentially highly potent drugs for 2019-nCoV The World Health Organization (WHO) has declared the 2019 novel coronavirus (2019-nCoV) infection outbreak a global health emergency. Currently, there is no effective anti-2019-nCoV medication. The sequence identity of the 3CL proteases of 2019-nCoV and SARS is 96%, which provides a sound foundation for structural-based drug repositioning (SBDR). Based on a SARS 3CL protease X-ray crystal structure, we construct a 3D homology structure of 2019-nCoV 3CL protease. Based on this structure and existing experimental datasets for SARS 3CL protease inhibitors, we develop an SBDR model based on machine learning and mathematics to screen 1465 drugs in the DrugBank that have been approved by the U.S. Food and Drug Administration (FDA). We found that many FDA approved drugs are potentially highly potent to 2019-nCoV.

negative: Nanoparticle Vaccines Against Infectious Diseases Due to emergence of new variants of pathogenic micro-organisms the treatment and immunization of infectious diseases have become a great challenge in the past few years. In the context of vaccine development remarkable efforts have been made to develop new vaccines and also to improve the efficacy of existing vaccines against specific diseases. To date, some vaccines are developed from protein subunits or killed pathogens, whilst several vaccines are based on live-attenuated organisms, which carry the risk of regaining their pathogenicity under certain immunocompromised conditions. To avoid this, the development of risk-free effective vaccines in conjunction with adequate delivery systems are considered as an imperative need to obtain desired humoral and cell-mediated immunity against infectious diseases. In the last several years, the use of nanoparticle-based vaccines has received a great attention to improve vaccine efficacy, immunization strategies, and targeted delivery to achieve desired immune responses at the cellular level. To improve vaccine efficacy, these nanocarriers should protect the antigens from premature proteolytic degradation, facilitate antigen uptake and processing by antigen presenting cells, control release, and should be safe for human use. Nanocarriers composed of lipids, proteins, metals or polymers have already been used to attain some of these attributes. In this context, several physico-chemical properties of nanoparticles play an important role in the determination of vaccine efficacy. This review article focuses on the applications of nanocarrier-based vaccine formulations and the strategies used for the functionalization of nanoparticles to accomplish efficient delivery of vaccines in order to induce desired host immunity against infectious diseases.

negative: SARS-CoV-2: the emergence of a viral pathogen causing havoc on human existence

negative: Structural basis for the recognition of SARS-CoV-2 by full-length human ACE2 Angiotensin-converting enzyme 2 (ACE2) is the cellular receptor for severe acute respiratory syndrome–coronavirus (SARS-CoV) and the new coronavirus (SARS-CoV-2) that is causing the serious coronavirus disease 2019 (COVID-19) epidemic. Here, we present cryo–electron microscopy structures of full-length human ACE2 in the presence of the neutral amino acid transporter B(0)AT1 with or without the receptor binding domain (RBD) of the surface spike glycoprotein (S protein) of SARS-CoV-2, both at an overall resolution of 2.9 angstroms, with a local resolution of 3.5 angstroms at the ACE2-RBD interface. The ACE2-B(0)AT1 complex is assembled as a dimer of heterodimers, with the collectrin-like domain of ACE2 mediating homodimerization. The RBD is recognized by the extracellular peptidase domain of ACE2 mainly through polar residues. These findings provide important insights into the molecular basis for coronavirus recognition and infection.

negative: Infection and Rapid Transmission of SARS-CoV-2 in Ferrets The outbreak of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in China and rapidly spread worldwide. To prevent SARS-CoV-2 dissemination, understanding the in vivo characteristics of SARS-CoV-2 is a high priority. We report a ferret model of SARS-CoV-2 infection and transmission that recapitulates aspects of human disease. SARS-CoV-2-infected ferrets exhibit elevated body temperatures and virus replication. Although fatalities were not observed, SARS-CoV-2-infected ferrets shed virus in nasal washes, saliva, urine, and feces up to 8 days post-infection. At 2 days post-contact, SARS-CoV-2 was detected in all naive direct contact ferrets. Furthermore, a few naive indirect contact ferrets were positive for viral RNA, suggesting airborne transmission. Viral antigens were detected in nasal turbinate, trachea, lungs, and intestine with acute bronchiolitis present in infected lungs. Thus, ferrets represent an infection and transmission animal model of COVID-19 that may facilitate development of SARS-CoV-2 therapeutics and vaccines.

negative: Comparative Global Epidemiological Investigation of SARS-CoV-2 and SARS-CoV Diseases Using Meta-MUMS Tool Through Incidence, Mortality, and Recovery Rates COVID-19 is a novel coronavirus that was reported by the world health organization in late December 2019. As an unexplained respiratory disease epidemic, which is similar to respiratory syndrome coronavirus SARS-CoV, it rapidly spread all over the world. The study aims to compare several parameters of COVID-19 and SARS-CoV infectious diseases in terms of incidence, mortality, and recovery rates. The publicly available dataset Worldometer (extracted on April 5, 2020) confirmed by WHO report was available for meta-analysis purposes using the Meta-MUMS tool. And, the reported outcomes of the analysis used a random-effects model to evaluate the event rate, and risk ratios thorough subgroup analysis forest plots. Seventeen countries for COVID-19 and eight countries of SARS infections, including COVID-19 group n = 1124243, and SARS-CoV group n = 8346, were analyzed. In this meta-analysis, a random effect model of relations of incidence, mortality, and recovery rates of COVID-19 and SARS world infections were determined. The meta-analysis and forest plots of two viral world infections showed that the incidence rate of COVID-19 infection is more than SARS infections, while recovery and mortality event rates of SARS-CoV are more than COVID-19 infection. And subgroup analysis showed that the mortality and recovery rates were higher in both SARS-CoV wand COVID-19 in comparison to incidence and mortality rates, respectively. In conclusion, the meta-analysis approach on the abovementioned dataset revealed the epidemiological and statistical analyses for comparing COVID-19 and SARS-CoV outbreaks.

negative: Immunopathogenesis of coronavirus infections: implications for SARS At the end of 2002, the first cases of severe acute respiratory syndrome (SARS) were reported, and in the following year, SARS resulted in considerable mortality and morbidity worldwide. SARS is caused by a novel species of coronavirus (SARS-CoV) and is the most severe coronavirus-mediated human disease that has been described so far. On the basis of similarities with other coronavirus infections, SARS might, in part, be immune mediated. As discussed in this Review, studies of animals that are infected with other coronaviruses indicate that excessive and sometimes dysregulated responses by macrophages and other pro-inflammatory cells might be particularly important in the pathogenesis of disease that is caused by infection with these viruses. It is hoped that lessons from such studies will help us to understand more about the pathogenesis of SARS in humans and to prevent or control outbreaks of SARS in the future.

negative: Immunity toward H1N1 influenza hemagglutinin of historical and contemporary strains suggests protection and vaccine failure Evolution of H1N1 influenza A outbreaks of the past 100 years is interesting and significantly complex and details of H1N1 genetic drift remains unknown. Here we investigated the clinical characteristics and immune cross-reactivity of significant historical H1N1 strains. We infected ferrets with H1N1 strains from 1943, 1947, 1977, 1986, 1999, and 2009 and showed each produced a unique clinical signature. We found significant cross-reactivity between viruses with similar HA sequences. Interestingly, A/FortMonmouth/1/1947 antisera cross-reacted with A/USSR/90/1977 virus, thought to be a 1947 resurfaced virus. Importantly, our immunological data that didn't show cross-reactivity can be extrapolated to failure of past H1N1 influenza vaccines, ie. 1947, 1986 and 2009. Together, our results help to elucidate H1N1 immuno-genetic alterations that occurred in the past 100 years and immune responses caused by H1N1 evolution. This work will facilitate development of future influenza therapeutics and prophylactics such as influenza vaccines.

negative: The potential genetic network of human brain SARS-CoV-2 infection The literature reports several symptoms of SARS-CoV-2 in humans such as fever, cough, fatigue, pneumonia, and headache. Furthermore, patients infected with similar strains (SARS-CoV and MERS-CoV) suffered testis, liver, or thyroid damage. Angiotensin-converting enzyme 2 (ACE2) serves as an entry point into cells for some strains of coronavirus (SARS-CoV, MERS-CoV, SARS-CoV-2). Our hypothesis was that as ACE2 is essential to the SARS-CoV-2 virus invasion, then brain regions where ACE2 is the most expressed are more likely to be disturbed by the infection. Thus, the expression of other genes which are also over-expressed in those damaged areas could be affected. We used mRNA expression levels data of genes provided by the Allen Human Brain Atlas (ABA), and computed spatial correlations with the LinkRbrain platform. Genes whose co-expression is spatially correlated to that of ACE2 were then clustered into 16 groups, depending on the organ in which they are the most expressed (as described by the NCBI genes database). The list of organs where genes sharing local over-expression with the ACE2 gene are the most expressed is astonishingly similar to the organs affected by Covid-19.

negative: A review on Promising vaccine development progress for COVID-19 disease Abstract The emergence of the strain of coronavirus SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) that causes corona virus disease 2019 (COVID-19) and its impact on in the world have made imperative progress to develop an effective and safe vaccine. Despite several measures undertaken, the spread of this virus is ongoing. So far, more than 1,560,000 cases and 1000,000 deaths occurred in the world. Efforts have been made to develop vaccines against human coronavirus (CoV) infections such as MERS and SARS. However, currently, no approved vaccine exists for these coronavirus strains. Such Previous research efforts to develop a coronavirus vaccine in the years following the 2003 pandemic have opened the door for the scientist to design a new vaccine for the COVID-19. Both SARS-CoV and SARS-CoV-2 has a high degree of genetic similarity and bind to the same host cell ACE2 receptor. By using different vaccine development platforms including whole virus vaccines, recombinant protein subunit vaccines, and nucleic acid vaccines several candidates displayed efficacy in vitro studies but few progressed to clinical trials. This review provides a brief introduction of the general features of SARS-CoV-2 and discusses the current progress of ongoing advances in designing vaccine development efforts to counter COVID-19.

negative: Minimally invasive surgery at the time of Covid-19: The OR staff needs protection

negative: Sub-national variation in measles vaccine coverage and outbreak risk: a case study from a 2010 outbreak in Malawi BACKGROUND: Despite progress towards increasing global vaccination coverage, measles continues to be one of the leading, preventable causes of death among children worldwide. Whether and how to target sub-national areas for vaccination campaigns continues to remain a question. We analyzed three metrics for prioritizing target areas: vaccination coverage, susceptible birth cohort, and the effective reproductive ratio (R(E)) in the context of the 2010 measles epidemic in Malawi. METHODS: Using case-based surveillance data from the 2010 measles outbreak in Malawi, we estimated vaccination coverage from the proportion of cases reporting with a history of prior vaccination at the district and health facility catchment scale. Health facility catchments were defined as the set of locations closer to a given health facility than to any other. We combined these estimates with regional birth rates to estimate the size of the annual susceptible birth cohort. We also estimated the effective reproductive ratio, R(E), at the health facility polygon scale based on the observed rate of exponential increase of the epidemic. We combined these estimates to identify spatial regions that would be of high priority for supplemental vaccination activities. RESULTS: The estimated vaccination coverage across all districts was 84%, but ranged from 61 to 99%. We found that 8 districts and 354 health facility catchments had estimated vaccination coverage below 80%. Areas that had highest birth cohort size were frequently large urban centers that had high vaccination coverage. The estimated R(E) ranged between 1 and 2.56. The ranking of districts and health facility catchments as priority areas varied depending on the measure used. CONCLUSIONS: Each metric for prioritization may result in discrete target areas for vaccination campaigns; thus, there are tradeoffs to choosing one metric over another. However, in some cases, certain areas may be prioritized by all three metrics. These areas should be treated with particular concern. Furthermore, the spatial scale at which each metric is calculated impacts the resulting prioritization and should also be considered when prioritizing areas for vaccination campaigns. These methods may be used to allocate effort for prophylactic campaigns or to prioritize response for outbreak response vaccination.

negative: Infectious Complications of Transplantation Post-transplant infection is a common cause of graft deterioration, morbidity and mortality. It is also responsible for delayed discharge, multiple, often prolonged admissions and thus a significant clinical challenge. Infections can be donor derived, pre-existing in the recipient, nosocomial and opportunistic. For each of these categories, it is often possible to significantly reduce hazard and thus the adverse consequences by first identifying patients at high risk. As always, clinical vigilance is vital, but equally important is the establishment of robust clinical systems for prevention, screening and rapid treatment.

negative: Coronavirus: la emergencia geriátrica de 2020. Documento conjunto de la Sección de Cardiología Geriátrica de la Sociedad Española de Cardiología y la Sociedad Española de Geriatría y Gerontología./ [Coronavirus: the geriatric emergency of 2020. Joint document of the Geriatric Cardiology Section of the Spanish Society of Cardiology and the Spanish Society of Geriatrics and Gerontology] SARS-CoV2 infection, also known as COVID-19 (coronavirus infectious disease-19), was first identified in December 2019. In Spain, the first case of this infection was diagnosed on 31 January, 2020 and, by 30 March 2020, has caused 7340 deaths, especially in the elderly. Due to the rapidly evolving situation regarding this disease, the data reported in this article may be subject to modifications. The older population are particularly susceptible to COVID-19 infection and to developing severe disease. The higher morbidity and mortality rates in older people have been associated with comorbidity, especially cardiovascular disease, and frailty, which weakens the immune response. Due to both the number of affected countries and the number of cases, the current situation constitutes an ongoing pandemic and a major health emergency. Because Spain has one of the largest older populations in the world, COVID-19 has emerged as a geriatric emergency. This document has been prepared jointly between the Geriatric Cardiology Section of the Spanish Society of Cardiology and the Spanish Society of Geriatrics and Gerontology.

negative: Higher mortality in men from COVID19 infection-understanding the factors that drive the differences between the biological sexes. The emergent global pandemic caused by the rapid spread of Severe Acute Respiratory syndrome- Coronavirus-2 (SARS-CoV-2) has led to increased mortality and negatively impacted day to day activities of humankind within a short period of time. As the data is rapidly emerging from earlier outbreak locations around the world, there are efforts to assimilate this with the knowledge from prior epidemics and find rapid solutions for this. One of the observations and a recurring theme is the disproportionate differences in the incidence of infection and the consequent mortality between males and females. We, therefore, analyzed retrospective datasets from the previous epidemics and the ongoing pandemic in order to address these differences in clinical outcomes. The data shows that even though the infection rates are similar, the odds ratio of male mortality remains high, indicating a divergence in the crosstalk between the three pathogenic human Coronavirus (hCoVs)- the SARS-CoV, MERS-CoV and the SARS-CoV-2 and immune effectors in the two sexes. One proximate cause is the sex-specific modulation of the X-linked genes that can influence susceptibility to infection. Future studies are needed to confirm these findings, which can form the basis for developing rational strategies for ending the current and preventing future pandemics.

negative: Interferon-Gamma Modulation of the Local T Cell Response to Alphavirus Encephalomyelitis Infection of mice with Sindbis virus (SINV) provides a model for examining the role of the immune response to alphavirus infection of the central nervous system (CNS). Interferon-gamma (IFN-γ) is an important component of this response, and we show that SINV-infected differentiated neurons respond to IFN-γ in vitro by induction of antiviral genes and suppression of virus replication. To determine the in vivo effects of IFN-γ on SINV clearance and T cell responses, C57BL/6 mice lacking IFN-γ or IFN-γ receptor-1 were compared to wild-type (WT) mice after intracranial SINV infection. In WT mice, IFN-γ was first produced in the CNS by natural killer cells and then by CD4(+) and CD8(+) T cells. Mice with impaired IFN-γ signaling initiated clearance of viral RNA earlier than WT mice associated with CNS entry of more granzyme B-producing CD8(+) T cells. However, these mice established fewer CD8(+) tissue-resident memory T (T(RM)) cells and were more likely to experience reactivation of viral RNA synthesis late after infection. Therefore, IFN-γ suppresses the local development of granzyme B-expressing CD8(+) T cells and slows viral RNA clearance but promotes CD8(+) T(RM) cell establishment.

negative: Issues to be considered when planning sero-epidemiological studies in regions with a low incidence of SARS-CoV-2.

negative: Potential effect of blood purification therapy in reducing cytokine storm as a late complication of critically ill COVID-19

negative: Attenuation and restoration of severe acute respiratory syndrome coronavirus mutant lacking 2'-o-methyltransferase activity. UNLABELLED The sudden emergence of severe acute respiratory syndrome coronavirus (SARS-CoV) in 2002 and, more recently, Middle Eastern respiratory syndrome CoV (MERS-CoV) underscores the importance of understanding critical aspects of CoV infection and pathogenesis. Despite significant insights into CoV cross-species transmission, replication, and virus-host interactions, successful therapeutic options for CoVs do not yet exist. Recent identification of SARS-CoV NSP16 as a viral 2'-O-methyltransferase (2'-O-MTase) led to the possibility of utilizing this pathway to both attenuate SARS-CoV infection and develop novel therapeutic treatment options. Mutations were introduced into SARS-CoV NSP16 within the conserved KDKE motif and effectively attenuated the resulting SARS-CoV mutant viruses both in vitro and in vivo. While viruses lacking 2'-O-MTase activity had enhanced sensitivity to type I interferon (IFN), they were not completely restored in their absence in vivo. However, the absence of either MDA5 or IFIT1, IFN-responsive genes that recognize unmethylated 2'-O RNA, resulted in restored replication and virulence of the dNSP16 mutant virus. Finally, using the mutant as a live-attenuated vaccine showed significant promise for possible therapeutic development against SARS-CoV. Together, the data underscore the necessity of 2'-O-MTase activity for SARS-CoV pathogenesis and identify host immune pathways that mediate this attenuation. In addition, we describe novel treatment avenues that exploit this pathway and could potentially be used against a diverse range of viral pathogens that utilize 2'-O-MTase activity to subvert the immune system. IMPORTANCE Preventing recognition by the host immune response represents a critical aspect necessary for successful viral infection. Several viruses, including SARS-CoV, utilize virally encoded 2'-O-MTases to camouflage and obscure their viral RNA from host cell sensing machinery, thus preventing recognition and activation of cell intrinsic defense pathways. For SARS-CoV, the absence of this 2'-O-MTase activity results in significant attenuation characterized by decreased viral replication, reduced weight loss, and limited breathing dysfunction in mice. The results indicate that both MDA5, a recognition molecule, and the IFIT family play an important role in mediating this attenuation with restored virulence observed in their absence. Understanding this virus-host interaction provided an opportunity to design a successful live-attenuated vaccine for SARS-CoV and opens avenues for treatment and prevention of emerging CoVs and other RNA virus infections.

negative: SARS-CoV-2 contributes to altering the post-transcriptional regulatory networks across human tissues by sponging RNA binding proteins and micro-RNAs The outbreak of a novel coronavirus SARS-CoV2 responsible for COVID-19 pandemic has caused worldwide public health emergency. Due to the constantly evolving nature of the coronaviruses, SARS-CoV-2 mediated alteration on post-transcriptional gene regulation across human tissues remains elusive. In this study, we systematically dissected the crosstalk and dysregulation of human post-transcriptional regulatory networks governed by RNA binding proteins (RBPs) and micro-RNAs (miRs), due to SARS-CoV-2 infection. We uncovered that 13 out of 29 SARS-CoV-2 encoded proteins directly interact with 51 human RBPs of which majority of them were abundantly expressed in gonadal tissues and immune cells. We further performed functional analysis of differentially expressed genes in mock treated versus SARS-CoV-2 infected lung cells that revealed an enrichment for immune response, cytokine mediated signaling, and metabolism associated genes. This study also characterized the alternative splicing events in SARS-CoV-2 infected cells compared to control demonstrating that skipped exons and mutually exclusive exons were the most abundant events that potentially contributed to differential outcomes in response to viral infection. Motif enrichment analysis on the RNA genomic sequence of SARS-CoV-2 clearly revealed an enrichment for RBPs such as SRSFs, PCBPs, ELAVs and HNRNPs illustrating the sponging of RBPs by SARS-CoV-2 genome. Similar analysis to study the interactions of miRs with SARS-CoV-2 revealed the potential for several miRs to be sponged, suggesting that these interactions may contribute to altered pos-transcriptional regulation across human tissues. Given the need to understand the interactions of SARS-CoV-2 with key pos-transcriptional regulators in the human genome, this study provides a systematic analysis to dissect the role of dysregulated post-transcriptional regulatory networks controlled by RBPs and miRs, across tissues types during SARS-CoV2 infection.

negative: Therapeutic Options for Middle East Respiratory Syndrome Coronavirus (MERS-CoV) Infection: How Close Are We? Over 1100 cases of MERS-CoV have been reported since it was first identified in June 2012. Clinical presentation ranges from asymptomatic or mild illness to rapidly progressive disease with multi-organ failure and high mortality. Treatment has been largely supportive. A large number of compounds have been shown to have significant in vitro inhibitory activity against MERS-CoV. Until recently, macaques were the only suitable animal models for animal studies, hindering further clinical development of MERS-CoV therapy. However, the recent successful development of MERS-CoV infection model in transduced mice offers opportunities to accelerate clinical development of therapeutic agents for MERS-CoV infection. Currently available evidence supports further clinical investigation of interferon-based treatment regimens for patients with MERS-CoV. Combining interferon with mycophenolate and/or high-dose ribavirin appears especially promising. Monoclonal antibodies against various targets within MERS-CoV Spike protein have yielded encouraging in-vitro results. However, their safety and efficacy require confirmation in animal models and exploratory clinical trials.

negative: Risk of mortality associated with respiratory syncytial virus and influenza infection in adults BACKGROUND: Respiratory syncytial virus (RSV) infection constitutes a substantial disease burden in the general population. However, the risk of death for RSV infection has been rarely evaluated with confounders or comorbidities adjusted. We aimed to evaluate whether RSV infection is associated with higher mortality than seasonal influenza after adjusting for confounders and comorbidities and the effect of oseltamivir on the mortality in patients with influenza infection. METHODS: A retrospective cohort study was conducted on adult (≥18 years) patients admitted to the emergency department and ward of a university teaching hospital for suspected viral infection during 2013–2015 (N = 3743). RSV infection was diagnosed by multiplex PCR (N = 87). Adults hospitalized for seasonal influenza during the study period were enrolled as a comparison group (n = 312). The main outcome was 20-day all-cause mortality.We used Cox proportional hazard regression analyses to calculate the relative risk of death. RESULTS: Adult patients were less likely to be diagnosed with RSV than with influenza (2.3 vs 8.3%, respectively), were older and more likely to be diagnosed with pneumonia, chronic obstructive pulmonary disease, hypoxemia, and bacterial co-infection. In patients with RSV infection, the 20-day all-cause mortality was higher than that for influenza, (18.4 vs 6.7%, respectively). RSV infection showed significantly higher risk of death compared to the seasonal influenza group, with hazard ratio, 2.32 (95% CI, 1.17–4.58). Oseltamivir had no significant effect on mortality in patients with influenza. CONCLUSIONS: RSV infection was significantly associated with a higher risk of death than seasonal influenza, adjusted for potential confounders and comorbidities.

negative: COVID-19 infection in Italian people with diabetes: Lessons learned for our future (an experience to be used)

negative: Subjective neurological symptoms frequently occur in patients with SARS-CoV2 infection OBJECTIVE: Coronavirus disease 2019 (COVID-19) represents a novel pneumonia leading to severe acute respiratory syndrome (SARS). Recent studies documented that SARS-Coronavirus2 (SARS-CoV2), responsible for COVID-19, can affect the nervous system. The aim of the present observational study was to prospectively assess subjective neurological symptoms (sNS) in patients with SARS-CoV2 infection. METHODS: We included patients hospitalized at the University Hospital of Rome Tor Vergata, medical center dedicated to the treatment of patients with COVID-19 diagnosis, who underwent an anamnestic interview about sNS consisting of 13 items, each related to a specific symptom, requiring a dichotomized answer. RESULTS: We included 103 patients with SARS-CoV2 infection. Ninety-four patients (91.3%) reported at least one sNS. Sleep impairment was the most frequent symptom, followed by dysgeusia, headache, hyposmia, and depression. Women more frequently complained hyposmia, dysgeusia, dizziness, numbeness/paresthesias, daytime sleepiness, and muscle ache. Moreover, muscle ache and daytime sleepiness were more frequent in the first 2 days after admission. Conversely, sleep impairment was more frequent in patients with more than 7 days of hospitalization. In these patients we also documented higher white blood cells and lower C-reactive protein levels. These laboratory findings correlated with the occurrence of hyposmia, dysgeusia, headache, daytime sleepiness, and depression. CONCLUSIONS: Patients with SARS-CoV2 infection frequently present with sNS. These symptoms were present from the early phases of the disease. The possibly intrinsic neurotropic properties of SARS-CoV2 may justify the very high frequency of sNS. Further studies targeted at investigating the consequences of SARS-CoV2 infection on the CNS should be planned.

negative: The Effects of Pre-Existing Antibodies on Live-Attenuated Viral Vaccines Live-attenuated vaccines (LAVs) have achieved remarkable successes in controlling virus spread, as well as for other applications such as cancer immunotherapy. However, with rapid increases in international travel, globalization, geographic spread of viral vectors, and widespread use of vaccines, there is an increasing need to consider how pre-exposure to viruses which share similar antigenic regions can impact vaccine efficacy. Pre-existing antibodies, derived from either from maternal–fetal transmission, or by previous infection or vaccination, have been demonstrated to interfere with vaccine immunogenicity of measles, adenovirus, and influenza LAVs. Immune interference of LAVs can be caused by the formation of virus–antibody complexes that neutralize virus infection in antigen-presenting cells, or by the cross-linking of the B-cell receptor with the inhibitory receptor, FcγRIIB. On the other hand, pre-existing antibodies can augment flaviviral LAV efficacy such as that of dengue and yellow fever virus, especially when pre-existing antibodies are present at sub-neutralizing levels. The increased vaccine immunogenicity can be facilitated by antibody-dependent enhancement of virus infection, enhancing virus uptake in antigen-presenting cells, and robust induction of innate immune responses that promote vaccine immunogenicity. This review examines the literature on this topic and examines the circumstances where pre-existing antibodies can inhibit or enhance LAV efficacy. A better knowledge of the underlying mechanisms involved could allow us to better manage immunization in seropositive individuals and even identify possibilities that could allow us to exploit pre-existing antibodies to boost vaccine-induced responses for improved vaccine efficacy.

negative: Better Epitope Discovery, Precision Immune Engineering, and Accelerated Vaccine Design Using Immunoinformatics Tools Computational vaccinology includes epitope mapping, antigen selection, and immunogen design using computational tools. Tools that facilitate the in silico prediction of immune response to biothreats, emerging infectious diseases, and cancers can accelerate the design of novel and next generation vaccines and their delivery to the clinic. Over the past 20 years, vaccinologists, bioinformatics experts, and advanced programmers based in Providence, Rhode Island, USA have advanced the development of an integrated toolkit for vaccine design called iVAX, that is secure and user-accessible by internet. This integrated set of immunoinformatic tools comprises algorithms for scoring and triaging candidate antigens, selecting immunogenic and conserved T cell epitopes, re-engineering or eliminating regulatory T cell epitopes, and re-designing antigens to induce immunogenicity and protection against disease for humans and livestock. Commercial and academic applications of iVAX have included identifying immunogenic T cell epitopes in the development of a T-cell based human multi-epitope Q fever vaccine, designing novel influenza vaccines, identifying cross-conserved T cell epitopes for a malaria vaccine, and analyzing immune responses in clinical vaccine studies. Animal vaccine applications to date have included viral infections of pigs such as swine influenza A, PCV2, and African Swine Fever. “Rapid-Fire” applications for biodefense have included a demonstration project for Lassa Fever and Q fever. As recent infectious disease outbreaks underscore the significance of vaccine-driven preparedness, the integrated set of tools available on the iVAX toolkit stand ready to help vaccine developers deliver genome-derived, epitope-driven vaccines.

negative: COVID-19 for the Cardiologist: A Current Review of the Virology, Clinical Epidemiology, Cardiac and Other Clinical Manifestations and Potential Therapeutic Strategies Summary The coronavirus disease-2019 (COVID-19), a contagious disease caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV2), has reached pandemic status. As it spreads across the world, it has overwhelmed healthcare systems, strangled the global economy and led to a devastating loss of life. Widespread efforts from regulators, clinicians and scientists are driving a rapid expansion of knowledge of the SARS-CoV2 virus and the COVID-19 disease. We review the most current data with a focus on our basic understanding of the mechanism(s) of disease and translation to the clinical syndrome and potential therapeutics. We discuss the basic virology, epidemiology, clinical manifestation, multi-organ consequences, and outcomes. With a focus on cardiovascular complications, we propose several mechanisms of injury. The virology and potential mechanism of injury form the basis for a discussion of potential disease-modifying therapies.

negative: Severe Middle East Respiratory Syndrome (MERS) Pneumonia Abstract Middle East Respiratory Syndrome (MERS) is a viral respiratory infection, which ranges from asymptomatic infection to severe pneumonia and multiorgan failure, caused by a novel coronavirus named Middle East Respiratory Syndrome Coronavirus (MERS-CoV). Majority of cases have been reported from Saudi Arabia. MERS cases occur as sporadic cases or as clusters or hospital outbreaks. Dromedary camels are thought to be a host for MERS-CoV. Direct contact with dromedary camels within 14days prior to infection was identified as an independent risk factor for MERS. Diagnosis of MERS is based on a positive real-time reverse transcriptase polymerase chain reaction (rRT-PCR), obtained from a respiratory specimen. The mainstay of management of MERS-CoV infection is supportive care. There is no specific antiviral therapy for MERS-CoV infection at present, although several modalities of treatment options have been examined or are under investigation.

negative: Two complex, adenovirus-based vaccines that together induce immune responses to all four dengue virus serotypes. Dengue virus infections can cause hemorrhagic fever, shock, encephalitis, and even death. Worldwide, approximately 2.5 billion people live in dengue-infested regions with about 100 million new cases each year, although many of these infections are believed to be silent. There are four antigenically distinct serotypes of dengue virus; thus, immunity from one serotype will not cross-protect from infection with the other three. The difficulties that hamper vaccine development include requirements of the natural conformation of the envelope glycoprotein to induce neutralizing immune responses and the necessity of presenting antigens of all four serotypes. Currently, the only way to meet these requirements is to use a mixture of four serotypes of live attenuated dengue viruses, but safety remains a major problem. In this study, we have developed the basis for a tetravalent dengue vaccine using a novel complex adenovirus platform that is capable of expressing multiple antigens de novo. This dengue vaccine is constructed as a pair of vectors that each expresses the premembrane and envelope genes of two different dengue virus serotypes. Upon vaccination, the vaccine expressed high levels of the dengue virus antigens in cells to mimic a natural infection and induced both humoral and cellular immune responses against multiple serotypes of dengue virus in an animal model. Further analyses show the humoral responses were indeed neutralizing against all four serotypes. Our studies demonstrate the concept of mimicking infections to induce immune responses by synthesizing dengue virus membrane antigens de novo and the feasibility of developing an effective tetravalent dengue vaccine by vector-mediated expression of glycoproteins of the four serotypes.

negative: Clinical characteristics and reasons of different duration from onset to release from quarantine for patients with COVID-19 Outside Hubei province, China. Objective: To find out more characteristics and rules of COVID-19 by analyzing the clinical course of COVID-19 patients in a region outside Hubei province. Methods: 37 cases diagnosed adult COVID-19 cases of general characteristics, history of epidemiology, chronic underlying diseases,clinical symptoms and complications, chest CT, biochemical monitoring, severity assessment, treatment and outcome were retrospectively analyzed, and according to the duration from onset to release from quarantine were divided into 20-day group and > 20-day group, compare the similarities and differences between the two groups. Results: Among the 37 patients, 5 were mild, 30 were moderate, 1 was severe and 1 was critical. All the patients were released from quarantine without death. The average duration from onset to release from quarantine was 20.2±6.6 days, The average length of stay from onset to hospitalization was 4.1±3.7 days, and hospitalization duration average 16.1± 6.2 days. The average age was 44.3±1.67 years. 78.4% of cases were caused by exposure to a confirmed patient or the workplace of a confirmed patient. The main symptoms were cough (67.6%), fever( 62.2%), shortness of breath (32.4%), fatigue (24.3%), sore throat (21.6%,) vomiting or diarrhea (21.6%). The white blood cell count was decreased in 27.0% of the patients, and the lymphocyte count was decreased in 62.2% of the patients, of which 43.5% patients were <0.6 × 109/L. On admission, 86.5% of patients with chest CT showed pneumonia, including some asymptomatic patients. 68.8% of patients showed bilateral infiltration. In the > 20-day group, the average age was 49.9±1.38 years old, and the duration from onset to hospitalization was 5.5±3.9 days. Compared with the ≤20-day group, the age was older and and duration was longer, P < 0.05. All the 7 asymptomatic patients were ≤20-day group. When 37 patients were released from quarantine, the white blood cell count of 16.2% patients was <4.0 × 109/L, and the lymphocyte count of 59.5% patients was <1.1×109/L, and the absolute count of white blood cells and lymphocytes was 5.02 ± 1.34×109/L and 1.03± 0.34×109/L respectively , compared with those on admission, P >0.05. Conclusion: The majority of COVID-19 cases in the study area were mild and moderate, with good clinical outcomes. There were some special characteristics in the clinical process. The reasons of duration from onset to release from quarantine were complex. There was no significant change in the number of granulocytes at the time of release from quarantine compared to the time of admission.

negative: Vaccine Development Against Middle East Respiratory Syndrome Various types of vaccines are under pre-clinical and clinical development to address the recent appearance of Middle East respiratory syndrome or MERS, an emerging infectious disease that has already caused over 600 deaths and remains a threat to world health. The causative agent for this respiratory disease is a member of the betacoronavirus genus, phylogenetically closely related to the SARS coronavirus that caused an international health emergency in 2002. With lessons learned from the outbreak of severe acute respiratory syndrome, and with undeniable technological advances, vaccine development against MERS was initially fast-paced and has produced several DNA and protein vaccine candidates with promising results during early pre-clinical testing. At least one vaccine candidate has even entered first-in-humans clinical trials now. With the number of MERS cases declining though and other infectious diseases attracting increased attention, the question remains, whether, similar to the situation after the SARS pandemic, vaccine development is halted or remains the priority it rightfully should.

negative: Immune Responses to rAAV6: The Influence of Canine Parvovirus Vaccination and Neonatal Administration of Viral Vector Recombinant adeno-associated viral (rAAV) vectors promote long-term gene transfer in many animal species. Significant effort has focused on the evaluation of rAAV delivery and the immune response in both murine and canine models of neuromuscular disease. However, canines provided for research purposes are routinely vaccinated against canine parvovirus (CPV). rAAV and CPV possess significant homology and are both parvoviruses. Thus, any immune response generated to CPV vaccination has the potential to cross-react with rAAV vectors. In this study, we investigated the immune response to rAAV6 delivery in a cohort of CPV-vaccinated canines and evaluated multiple vaccination regimens in a mouse model of CPV-vaccination. We show that CPV-vaccination stimulates production of neutralizing antibodies with minimal cross-reactivity to rAAV6. In addition, no significant differences were observed in the magnitude of the rAAV6-directed immune response between CPV-vaccinated animals and controls. Moreover, CPV-vaccination did not inhibit rAAV6-mediated transduction. We also evaluated the immune response to early rAAV6-vaccination in neonatal mice. The influence of maternal hormones and cytokines leads to a relatively permissive state in the neonate. We hypothesized that immaturity of the immune system would permit induction of tolerance to rAAV6 when delivered during the neonatal period. Mice were vaccinated with rAAV6 at 1 or 5 days of age, and subsequently challenged with rAAV6 exposure during adulthood via two sequential IM injections, 1 month apart. All vaccinated animals generated a significant neutralizing antibody response to rAAV6-vaccination that was enhanced following IM injection in adulthood. Taken together, these data demonstrate that the immune response raised against rAAV6 is distinct from that which is elicited by the standard parvoviral vaccines and is sufficient to prevent stable tolerization in neonatal mice.

negative: Virus-Related Pathology: Is the Continued Presence of the Virus Necessary? Publisher Summary This chapter examines the effect of viruses in inducing modifications in chromosomes, immune system interactions, and cell metabolism to support such a hypothesis that virus may no longer be present when the pathology appears. When vaccines were available to protect the population against the major epidemics, then chronic, recurrent, or persistent infections came into focus. Viruses are everywhere and all organisms are permanently exposed to them. The result of this contact depends on the particular moment a t which a given cell is exposed to the virus. Rubella, for example, provokes a very benign disease in adults, but can induce abnormalities in the differentiating fetus. Although interferon is active against virus aggression, excess interferon has a toxic effect and can block differentiation. The capacity of several viruses to act as cellular mutagens by modifying chromosomes is well established, whatever the molecular mechanism may be. Mutations at the cellular level were carefully analyzed for their tumorigenic potential.

negative: Subunit Vaccines Against Emerging Pathogenic Human Coronaviruses Seven coronaviruses (CoVs) have been isolated from humans so far. Among them, three emerging pathogenic CoVs, including severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), and a newly identified CoV (2019-nCoV), once caused or continue to cause severe infections in humans, posing significant threats to global public health. SARS-CoV infection in humans (with about 10% case fatality rate) was first reported from China in 2002, while MERS-CoV infection in humans (with about 34.4% case fatality rate) was first reported from Saudi Arabia in June 2012. 2019-nCoV was first reported from China in December 2019, and is currently infecting more than 70000 people (with about 2.7% case fatality rate). Both SARS-CoV and MERS-CoV are zoonotic viruses, using bats as their natural reservoirs, and then transmitting through intermediate hosts, leading to human infections. Nevertheless, the intermediate host for 2019-nCoV is still under investigation and the vaccines against this new CoV have not been available. Although a variety of vaccines have been developed against infections of SARS-CoV and MERS-CoV, none of them has been approved for use in humans. In this review, we have described the structure and function of key proteins of emerging human CoVs, overviewed the current vaccine types to be developed against SARS-CoV and MERS-CoV, and summarized recent advances in subunit vaccines against these two pathogenic human CoVs. These subunit vaccines are introduced on the basis of full-length spike (S) protein, receptor-binding domain (RBD), non-RBD S protein fragments, and non-S structural proteins, and the potential factors affecting these subunit vaccines are also illustrated. Overall, this review will be helpful for rapid design and development of vaccines against the new 2019-nCoV and any future CoVs with pandemic potential. This review was written for the topic of Antivirals for Emerging Viruses: Vaccines and Therapeutics in the Virology section of Frontiers in Microbiology.

negative: Heterologous Immunity between Adenoviruses and Hepatitis C Virus: A New Paradigm in HCV Immunity and Vaccines Adenoviruses (Ad) are commonly used as vectors for gene therapy and/or vaccine delivery. Recombinant Ad vectors are being tested as vaccines for many pathogens. We have made a surprising observation that peptides derived from various hepatitis C virus (HCV) antigens contain extensive regions of homology with multiple adenovirus proteins, and conclusively demonstrate that adenovirus vector can induce robust, heterologous cellular and humoral immune responses against multiple HCV antigens. Intriguingly, the induction of this cross-reactive immunity leads to significant reduction of viral loads in a recombinant vaccinia-HCV virus infected mouse model, supporting their role in antiviral immunity against HCV. Healthy human subjects with Ad-specific pre-existing immunity demonstrated cross-reactive cellular and humoral immune responses against multiple HCV antigens. These findings reveal the potential of a previously uncharacterized property of natural human adenovirus infection to dictate, modulate and/or alter the course of HCV infection upon exposure. This intrinsic property of adenovirus vectors to cross-prime HCV immunity can also be exploited to develop a prophylactic and/or therapeutic vaccine against HCV.

negative: SARS-CoV and IFN: Too Little, Too Late Dysregulated type I interferon (IFN-I) expression can lead to severe pathology and disease. In this issue of Cell Host & Microbe, Channappanavar et al. (2016) use a SARS-coronavirus animal model to describe how rapid and robust virus replication with delayed IFN-I can lead to lung immunopathology, with fatal outcomes.

negative: Exercising caution in correlating COVID-19 incidence and mortality rates with BCG vaccination policies due to variable rates of SARS CoV-2 testing TThe Bacillus Calmette-Guerin (BCG) vaccine provides protection against tuberculosis (TB), and is proposed to provide protection to non-TB infectious diseases. The COVID-19 outbreak results from infection with the novel coronavirus SARS-CoV-2 (CoV-2) and was declared a pandemic on March 11th, 2020. We queried whether the BCG vaccine offers protection against CoV-2 infection. We observed that countries with a current universal BCG vaccination policy have a significantly lower COVID-19 incidence than countries which never had a universal BCG policy or had one in the past. However, population density, median age, TB incidence, urban population, and, most significantly, CoV-2 testing rate, were also connected with BCG policy and could potentially confound the analysis. By limiting the analysis to countries with high CoV-2 testing rates, defined as greater than 2,500 tests per million inhabitants, these parameters were no longer statistically associated with BCG policy. When analyzing only countries with high testing rates, there was no longer a significant association between the number of COVID-19 cases per million inhabitants and the BCG vaccination policy. Although preliminary, our analyses indicate that the BCG vaccination may not offer protection against CoV-2 infection. While reporting biases may confound our observations, our findings support exercising caution in determining potential correlation between BCG vaccination and COVID-19 incidence, in part due significantly lower rates of CoV-2 testing per million inhabitants in countries with current universal BCG vaccination policy.

negative: Vaccines for emerging infectious diseases: Lessons from MERS coronavirus and Zika virus The past decade and a half has been characterized by numerous emerging infectious diseases. With each new threat, there has been a call for rapid vaccine development. Pathogens such as the Middle East Respiratory Syndrome coronavirus (MERS-CoV) and the Zika virus represent either new viral entities or viruses emergent in new geographic locales and characterized by novel complications. Both serve as paradigms for the global spread that can accompany new pathogens. In this paper, we review the epidemiology and pathogenesis of MERS-CoV and Zika virus with respect to vaccine development. The challenges in vaccine development and the approach to clinical trial design to test vaccine candidates for disease entities with a changing epidemiology are discussed.

negative: Deliberate release: Plague – A review Yersinia pestis is the causative agent of plague and is considered one of the most likely pathogens to be used as a bioweapon. In humans, plague is a severe clinical infection that can rapidly progress with a high mortality despite antibiotic therapy. Therefore, early treatment of Y. pestis infection is crucial. This review provides an overview of its clinical manifestations, diagnosis, treatment, prophylaxis, and protection requirements for the use of clinicians. We discuss the likelihood of a deliberate release of plague and the feasibility of obtaining, isolating, culturing, transporting and dispersing plague in the context of an attack aimed at a westernized country. The current threat status and the medical and public health responses are reviewed. We also provide a brief review of the potential prehospital treatment strategy and vaccination against Y. pestis. Further, we discuss the plausibility of antibiotic resistant plague bacterium, F1-negative Y. pestis, and also the possibility of a plague mimic along with potential strategies of defense against these. An extensive literature search on the MEDLINE, EMBASE, and Web of Science databases was conducted to collate papers relevant to plague and its deliberate release. Our review concluded that the deliberate release of plague is feasible but unlikely to occur, and that a robust public health response and early treatment would rapidly halt the transmission of plague in the population. Front-line clinicians should be aware of the potential of a deliberate release of plague and prepared to instigate early isolation of patients. Moreover, front-line clinicians should be weary of the possibility of suicide attackers and mindful of the early escalation to public health organizations.

negative: Preparedness among Ophthalmologists: During and Beyond the COVID-19 Pandemic

negative: Natural infection with the porcine respiratory coronavirus induces protective lactogenic immunity against transmissible gastroenteritis Abstract Our objective was to evaluate the level of passive protection against transmissible gastroenteritis (TGE) among 57 newborn piglets nursing from seven seropositive sows previously naturally infected with porcine respiratory coronavirus (PRCV). After challenge exposure we observed mortality rates of 44% for litters of seven PRCV-infected sows, 40% for litters of four sows orally immunized with the attenuated TGEV strain Nouzilly, and 91% for litters of seven seronegative susceptible sows. A blocking ELISA with two appropriate monoclonal antibodies distinguished serological responses of PRCV-infected sows from those of TGEV-immunized sows. The results suggest that natural infection of the sow with PRCV may induce a degree of protective lactogenic immunity against TGE.

negative: Antibody dynamics in BRSV-infected Danish dairy herds as determined by isotype-specific immunoglobulins Abstract Using specific ELISAs, antibody levels of four different isotypes to bovine respiratory syncytial virus (BRSV) were determined in calves, following experimental BRSV infection. Most calves experienced an increase in the specific IgM and IgG1 titres about 6–10 days after infection with BRSV. The IgM titre was transient showing positive titres for only 5–10 days, while specific IgG1 was present for a longer time. IgA was detected concomitantly with IgM but at a lower level. Production of IgG2 anti-BRSV antibodies was detected from 3 weeks after infection. In two closed herds, repeated blood samplings were performed on young stock to analyse maternal immunity. The passively transferred antibodies were mainly of the IgG1 isotype and the half-life of IgG1 to BRSV was estimated to be 26.6 days. One of the herds had an outbreak of enzootic pneumonia, diagnosed to be caused by BRSV. Furthermore, another herd with acute BRSV was followed by weekly blood samples in six calves; in both herds IgM and IgG1 was detected shortly after the appearance of clinical signs. Serum samples from 50 Danish dairy herds (453 samples) were tested for immunoglobulins of the isotypes IgG1, IgG2 and IgM. The presence of antibodies to BRSV was widespread and more than 54% of the samples had BRSV antibodies of both the IgG1 and IgG2 isotypes indicating a high herd prevalence to BRSV. Test samples from two herds out of 50 were free from all isotypes to BRSV.

negative: Wheat and chaffs in the interpretation of the current COVID19 outbreak in Italy The COVID19 outbreak in Italy is still a big concern. The Italian Government has recommended citizens to respect faithfully any compulsory legal disposition in order to stay home and so contributing in escaping viral contacts and slowing down epidemic. Emergency has raised a widely animated debate about how to read and comprehend the daily case numbers, the medical and caregivers availability, the needs to swab asymptomatic subjects. In this review the authors discuss about the many wheat and chaffs of how this virus disease is addressed .

negative: Literature-related discovery and innovation — update Abstract Literature-Related Discovery and Innovation (LRDI — formerly LRD — literature-related discovery) integrates 1) discovery generation from disparate literatures with 2) the wealth of knowledge contained in prior art to 3) potentially reverse chronic and infectious diseases and/or 4) potentially solve technical problems that appear intractable. This article describes the evolution of LRDI by the author and the insights gained/lessons learned over the past decade. To illustrate the potential power of LRDI, the article emphasizes the relationship between the results of our 2008 LRDI multiple sclerosis (MS) study and a recent demonstration of MS reversal. Lessons learned from the six LRDI medical studies done so far include: ⁎ The main operational problem in the author's LRDI approach is selecting the most important concepts from extremely large volumes of potential discovery retrieval. This is contrary to most published LRDI research, where the discovery focus is searching for rare events. ⁎ It is important to have topical specialist(s) working closely with information technologist(s); the topical specialist(s) applies judgment in selecting the most important concepts. ⁎ A functional form of the information retrieval query with proximity searching capability provides highly selective filtering for discovery retrieval and core prevention/treatment retrieval; the functional form of the query with proximity searching capability allows the use of full-text for discovery and core prevention/treatment. ⁎ Bibliographic coupling (identifying papers that share common references) combined with text-based relationships strengthens selection for potential discovery further. ⁎ Having ‘skin-in-the-game’ (being affected personally) relative to the medical outcome is a strong incentive to do whatever is necessary to solve the research problem. ⁎ Hormesis is critical to healing; relatively modest doses of stimuli tend to be beneficial, whereas relatively large doses may be harmful. The synergy of hormetic treatment doses produces effects larger than combinations of individual doses and requires smaller doses when combined; the synergy of hormetic doses allows conversion of megadoses of nutrients typically reported in lab/clinical studies to physiological (food-level) doses and associated increased safety. ⁎ Co-promoters (combinations of toxic stimuli required to produce disease symptoms) are extremely important for explaining seemingly conflicting results; if true co-promotion is present, elimination of one of the co-promoters may be adequate for removing symptoms, even though the overall problem persists. ⁎ Prior art (potential treatments already published in the literature but not pursued by mainline medicine) may have much to contribute to potentially solve many serious medical problems; much of prior art is overlooked, especially low-tech prior art (e.g., foods, food extracts, herbs, etc.). ⁎ Systemic and focused treatments are both necessary components of healing, but neither will be fully, or many times even partially, effective until the cause(s) is identified and removed. Any medical approach that involves administering treatments for chronic and infectious diseases without addressing the cause(s) results in a broad range of outcomes mainly involving substitution of one set of symptoms for another. ⁎ Past results of LRDI medical studies showed much overlap among preventatives/systemic treatments for different diseases. Differences will arise mainly in focused treatments, especially those involving high technology. ⁎ The central parameters to healing in much medical research are never identified nor reported. Many treatments require a combination of skilled practitioners, cause removal, and immune/neural/endocrine/circulatory systems to be healthy for full effectiveness, yet practitioner skill, degree of cause removal, and immune system et al. health are never reported. A lack of this information does not allow efficacy of different treatments to be compared. Reviews and meta-analyses that compare and draw conclusions about the effectiveness of these different treatments without the above critical information being reported are of extremely limited value and credibility. ⁎ Finally, the most important deficiency for fully reversing chronic and infectious diseases, as well as rapidly accelerating healing of injuries and wounds, is the credibility and integrity of the medical literature itself, especially in areas that concern commercial and government/political sensitivities. In the evaluation of many concepts that deviated from the norm, it was difficult to ascertain whether the difference was based on solid high-quality research, poor research, or deliberately skewed research.

negative: Mucosal Delivery of ACNPV Baculovirus Driving Expression of the Gal-Lectin LC3 Fragment Confers Protection against Amoebic Liver Abscess in Hamster Mucosal vaccination against amoebiasis using the Gal-lectin of E. histolytica has been proposed as one of the leading strategies for controlling this human disease. However, most mucosal adjuvants used are toxic and the identification of safe delivery systems is necessary. Here, we evaluate the potential of a recombinant Autographa californica baculovirus driving the expression of the LC3 fragment of the Gal-lectin to confer protection against amoebic liver abscess (ALA) in hamsters following oral or nasal immunization. Hamsters immunized by oral route showed complete absence (57.9%) or partial development (21%) of ALA, resulting in some protection in 78.9% of animals when compared with the wild type baculovirus and sham control groups. In contrast, nasal immunization conferred only 21% of protection efficacy. Levels of ALA protection showed lineal correlation with the development of an anti-amoebic cellular immune response evaluated in spleens, but not with the induction of seric IgG anti-amoeba antibodies. These results suggest that baculovirus driving the expression of E. histolytica vaccine candidate antigens is useful for inducing protective cellular and humoral immune responses following oral immunization, and therefore it could be used as a system for mucosal delivery of an anti-amoebic vaccine.

negative: Azithromycin and ciprofloxacin have a chloroquine-like effect on respiratory epithelial cells There is interest in the use of chloroquine/hydroxychloroquine (CQ/HCQ) and azithromycin (AZT) in COVID-19 therapy. Employing cystic fibrosis respiratory epithelial cells, here we show that drugs AZT and ciprofloxacin (CPX) act as acidotropic lipophilic weak bases and confer in vitro effects on intracellular organelles similar to the effects of CQ. These seemingly disparate FDA-approved antimicrobials display a common property of modulating pH of endosomes and trans-Golgi network. We believe this may in part help understand the potentially beneficial effects of CQ/HCQ and AZT in COVID-19, and that the present considerations of HCQ and AZT for clinical trials should be extended to CPX.

negative: Challenges in maintaining treatment services for people who use drugs during the COVID-19 pandemic The impact of COVID-19 across health services, including treatment services for people who use drugs, is emerging but likely to have a high impact. Treatment services for people who use drugs provide essential treatment services including opiate agonist treatment and needle syringe programmes alongside other important treatment programmes across all substance types including withdrawal and counselling services. Drug and alcohol hospital consultation-liaison clinicians support emergency departments and other services provided in hospital settings in efficiently managing patients who use drugs and present with other health problems. COVID-19 will impact on staff availability for work due to illness. Patients may require home isolation and quarantine periods. Ensuring ongoing supply of opiate treatment during these periods will require significant changes to how treatment is provided. The use of monthly depot buprenorphine as well as moving from a framework of supervised dosing will be required for patients on sublingual buprenorphine and methadone. Ensuring ready access to take-home naloxone for patients is crucial to reduce overdose risks. Delivery of methadone and buprenorphine to the homes of people with confirmed COVID-19 infections is likely to need to occur to support home isolation. People who use drugs are likely to be more vulnerable during the COVID-19 epidemic, due to poorer health literacy and stigma and discrimination towards this group. People who use drugs may prioritise drug use above other health concerns. Adequate supply of clean injecting equipment is important to prevent outbreaks of blood-borne viruses. Opiate users may misinterpret SARS-CoV2 symptoms as opiate withdrawal and manage this by using opioids. Ensuring people who use drugs have access to drug treatment as well as access to screening and testing for SARS-CoV2 where this is indicated is important.

negative: Schweres akutes respiratorisches Syndrom (SARS) The sudden appearance of the severe acute respiratory syndrome (SARS) in 2003 demonstrated to the world at large that despite the high standard of medical care in affected countries, a highly contagious emerging infectious disease could spread rapidly worldwide. By application and improvement of stringent infection control measures, a further spread of SARS could be stopped and the disease could so far be defeated. In the meantime, decisive progress in the knowledge about the structure and further characteristics of the SARS coronavirus (SARS-CoV) have been made, including the likely virus reservoir and the ways of spread. Validated diagnostic tests are now available and are further being improved. Effective vaccines and antiviral agents are being developed. Of imminent importance to prepare against a resurgence of SARS, remain, besides an exact knowledge about the viral pathogen and its possible further behavior, constant vigilance, early recognition, and instant isolation of suspected cases of SARS.

negative: What goes on board aircraft? Passengers include Aedes, Anopheles, 2019-nCoV, dengue, Salmonella, Zika, et al

negative: Coronavirus Infection in Cats Cats are susceptible to natural infection with several strains of feline coronavirus that result in either effusive and noneffusive feline infectious peritonitis or enteritis. Excretion of coronavirus by infected cats into the environment occurs by way of feces, oronasal secretions, and possibly urine. Clinical diagnosis of coronavirus infection is made by evaluating the case history, physical findings, laboratory results, and coronavirus antibody titers as well as ruling out analogous diseases. An intranasal temperature-sensitive feline infectious peritonitis coronavirus vaccine is available for use in healthy cats 16 weeks of age or older.

negative: Progress in the development of virus-like particle vaccines against respiratory viruses Introduction: Influenza virus, human respiratory syncytial virus (RSV), and human metapneumovirus (HMPV) are important human respiratory pathogens. Recombinant virus-like particle (VLP) vaccines are suggested to be potential promising platforms to protect against these respiratory viruses. This review updates important progress in the development of VLP vaccines against respiratory viruses. Areas Covered: This review summarizes progress in developing VLP and nanoparticle-based vaccines against influenza virus, RSV, and HMPV. The PubMed was mainly used to search for important research articles published since 2010 although earlier key articles were also referenced. The research area covered includes VLP and nanoparticle platform vaccines against seasonal, pandemic, and avian influenza viruses as well as RSV and HMPV respiratory viruses. The production methods, immunogenic properties, and vaccine efficacy of respiratory VLP vaccines in preclinical animal models and clinical studies were reviewed in this article. Expert opinion: Previous and current preclinical and clinical studies suggest that recombinant VLP and nanoparticle vaccines are expected to be developed as promising alternative platforms against respiratory viruses in future. Therefore, continued research efforts are warranted.

negative: Analysis of age-dependent resistance to murine coronavirus JHM infection in mice. Resistance to intraperitoneal murine coronavirus JHM infection in mice develops with age. C3H mice were found to be fully susceptible up to the age of 20 days and resistant after 23 days of age. Protection of susceptible animals from death due to infection could be achieved by maternal antibodies or by transfer of spleen cells from immunized, but not from nonimmunized, donor mice. Lack of protection by transfer of unprimed adult spleen cells was not related to immunosuppression by the host. Moreover, resistance of adult mice could not be abrogated by application of lymphocytes from suckling mice, although immune suppression by other means did affect the resistance of adult animals. On the other hand, spleen cells from nonimmunized mice could be primed with inactivated JHM virus in suckling mice and protected these mice from death due to a subsequent virus infection. Thus, the outcome of infection with JHM virus in suckling and adult mice can be influenced by immunological events, but is not exclusively due to the different stages of immune competence.

negative: Evaluation of inapparent nosocomial severe acute respiratory syndrome coronavirus infection in Vietnam by use of highly specific recombinant truncated nucleocapsid protein-based enzyme-linked immunosorbent assay. Severe acute respiratory syndrome (SARS) is a recently emerged human disease associated with pneumonia. Inapparent infection with SARS coronavirus (CoV) is not well characterized. To develop a safe, simple, and reliable screening method for SARS diagnosis and epidemiological study, two recombinant SARS-CoV nucleocapsid proteins (N' protein and (N)Delta(121) protein) were expressed in Escherichia coli, purified by affinity chromatography, and used as antigens for indirect, immunoglobulin G enzyme-linked immunosorbent assays (ELISA). Serum samples collected from healthy volunteers and SARS patients in Vietnam were used to evaluate the newly developed methods. The N' protein-based ELISA showed a highly nonspecific reaction. The (N)Delta(121) protein-based ELISA, with a nonspecific reaction drastically reduced compared to that of the nearly-whole-length N' protein-based ELISA, resulted in higher rates of positive reactions, higher titers, and earlier detection than the SARS-CoV-infected cell lysate-based ELISA. These results indicate that our newly developed SARS-CoV (N)Delta(121) protein-based ELISA is not only safe but also a more specific and more sensitive method to diagnose SARS-CoV infection and hence a useful tool for large-scale epidemiological studies. To identify inapparent SARS-CoV infections, serum samples collected from health care workers (HCWs) in Vietnam were screened by the (N)Delta(121) protein-based ELISA, and positive samples were confirmed by a virus neutralization test. Four out of 149 HCWs were identified to have inapparent SARS-CoV infection in Vietnam, indicating that subclinical SARS-CoV infection in Vietnam is rare but does exist.

negative: Low serum 25-hydroxyvitamin D levels are associated with increased risk of viral coinfections in wheezing children

negative: An enteric coronavirus of the rabbit: Detection by immunoelectron microscopy and identification of structural polypeptides The immunoelectron microscopy (IEM) technique has been used for the detection of a rabbit enteric coronavirus (RECV). Immune serum was prepared in guinea pigs; the viral antigen used for the immunization procedure was obtained from the caecum of a sick rabbit, concentrated by centrifugation and purified on Percoll gradient. In order to identify the viral particles used in the immunization procedure, the protein pattern of the particles was determined by electrophoresis and compared with the pattern of other known coronaviruses. Analysis of structural polypeptides of the purified viral particles revealed a pattern similar to that reported for other coronaviruses. These polypeptides cross reacted with two other coronavirus specific immune sera (IBV and TGE). IEM assay of fecal samples collected from healthy and sick rabbits showed the presence of immune aggregates in specimens from both sick and healthy rabbits. Those aggregates contained viral particules sharing morphological characteristics with other coronaviruses. Furthermore, IEM assay was shown to be more sensitive than a direct EM procedure to detect coronavirus particles in rabbit feces. This assay also allowed the detection of a larger number of chronic carriers.

negative: Epitope‐based peptide vaccine design and target site depiction against Middle East Respiratory Syndrome Coronavirus: an immune-informatics study BACKGROUND: Middle East Respiratory Syndrome Coronavirus (MERS-COV) is the main cause of lung and kidney infections in developing countries such as Saudi Arabia and South Korea. This infectious single-stranded, positive (+) sense RNA virus enters the host by binding to dipeptidyl-peptide receptors. Since no vaccine is yet available for MERS-COV, rapid case identification, isolation, and infection prevention strategies must be used to combat the spreading of MERS-COV infection. Additionally, there is a desperate need for vaccines and antiviral strategies. METHODS: The present study used immuno-informatics and computational approaches to identify conserved B- and T cell epitopes for the MERS-COV spike (S) protein that may perform a significant role in eliciting the resistance response to MERS-COV infection. RESULTS: Many conserved cytotoxic T-lymphocyte epitopes and discontinuous and linear B-cell epitopes were predicted for the MERS-COV S protein, and their antigenicity and interactions with the human leukocyte antigen (HLA) B7 allele were estimated. Among B-cell epitopes, QLQMGFGITVQYGT displayed the highest antigenicity-score, and was immensely immunogenic. Among T-cell epitopes, MHC class-I peptide YKLQPLTFL and MHC class-II peptide YCILEPRSG were identified as highly antigenic. Furthermore, docking analyses revealed that the predicted peptides engaged in strong bonding with the HLA-B7 allele. CONCLUSION: The present study identified several MERS-COV S protein epitopes that are conserved among various isolates from different countries. The putative antigenic epitopes may prove effective as novel vaccines for eradication and combating of MERS-COV infection.

negative: Síndrome respiratorio agudo grave y otros virus respiratorios emergentes en el siglo XXI

negative: Coronavirus envelope protein: current knowledge BACKGROUND: Coronaviruses (CoVs) primarily cause enzootic infections in birds and mammals but, in the last few decades, have shown to be capable of infecting humans as well. The outbreak of severe acute respiratory syndrome (SARS) in 2003 and, more recently, Middle-East respiratory syndrome (MERS) has demonstrated the lethality of CoVs when they cross the species barrier and infect humans. A renewed interest in coronaviral research has led to the discovery of several novel human CoVs and since then much progress has been made in understanding the CoV life cycle. The CoV envelope (E) protein is a small, integral membrane protein involved in several aspects of the virus’ life cycle, such as assembly, budding, envelope formation, and pathogenesis. Recent studies have expanded on its structural motifs and topology, its functions as an ion-channelling viroporin, and its interactions with both other CoV proteins and host cell proteins. MAIN BODY: This review aims to establish the current knowledge on CoV E by highlighting the recent progress that has been made and comparing it to previous knowledge. It also compares E to other viral proteins of a similar nature to speculate the relevance of these new findings. Good progress has been made but much still remains unknown and this review has identified some gaps in the current knowledge and made suggestions for consideration in future research. CONCLUSIONS: The most progress has been made on SARS-CoV E, highlighting specific structural requirements for its functions in the CoV life cycle as well as mechanisms behind its pathogenesis. Data shows that E is involved in critical aspects of the viral life cycle and that CoVs lacking E make promising vaccine candidates. The high mortality rate of certain CoVs, along with their ease of transmission, underpins the need for more research into CoV molecular biology which can aid in the production of effective anti-coronaviral agents for both human CoVs and enzootic CoVs.

negative: Group 2 coronaviruses prevent immediate early interferon induction by protection of viral RNA from host cell recognition Abstract Many viruses encode antagonists to prevent interferon (IFN) induction. Infection of fibroblasts with the murine hepatitis coronavirus (MHV) and SARS-coronavirus (SARS-CoV) did not result in nuclear translocation of interferon-regulatory factor 3 (IRF3), a key transcription factor involved in IFN induction, and induction of IFN mRNA transcription. Furthermore, MHV and SARS-CoV infection could not prevent IFN induction by poly (I:C) or Sendai virus, suggesting that these CoVs do not inactivate IRF3-mediated transcription regulation, but apparently prevent detection of replicative RNA by cellular sensory molecules. Our data indicate that shielding of viral RNA to host cell sensors might be the main general mechanism for coronaviruses to prevent IFN induction.

negative: Causes of hypogeusia/hyposmia in SARS‐CoV2 infected patients It is well appreciated that SARS‐CoV2 does not exclusively affect the lungs.(1,2) Virus‐RNA can be detected in most of the body compartments, including the cerebrospinal fluid (CSF).(3) Neurological manifestations have been recently investigated in a retrospective study of 214 SARS‐CoV2‐infected patients.(1) This article is protected by copyright. All rights reserved.

negative: The COVID-19 Registry in Rhineland-Palatinate in the context of international registry activities documenting COVID-19 outcomes

negative: Vaccination against enteric rota and coronaviruses in cattle and pigs: Enhancement of lactogenic immunity Passive immunity against enteric viral infections is dependent upon the continual presence in the gut lumen of a protective level of specific antibodies. This article examines methods currently used to enhance the titre and duration of specific antibody in the mammary secretions of cows and pigs with particular reference to rotavirus and coronavirus infections. In addition, some of the potential problems to be found in attempting to produce vaccines against these viral infections are outlined

negative: The pathogenesis and alternative treatment of SARS-CoV2

negative: Pathogenic T cells and inflammatory monocytes incite inflammatory storm in severe COVID-19 patients Pathogenic human coronavirus infections, such as severe acute respiratory syndrome CoV (SARS-CoV) and Middle East respiratory syndrome CoV (MERS-CoV), cause high morbidity and mortality1, 2 Recently, a severe pneumonia-associated respiratory syndrome caused by a new coronavirus (SARS-CoV-2) was reported at December 2019 in the city Wuhan, Hubei province, China3, 4, 5, which was also named as pneumonia-associated respiratory syndrome (PARS)6 and can cause coronavirus disease 2019 (COVID-19) to seriously endanger human health Up to 24th of February 2020, at least 77779 cases have been reported with 2666 fatal cases according to the report from China CDC However, the immune mechanism that potential orchestrated acute mortality from COVID-19 patients is still unknown Here we show that after the SARS-CoV-2 infection, CD4+ T lymphocytes are rapidly activated to become pathogenic T helper (Th) 1 cells and generate GM-CSF etc The cytokines environment induces inflammatory CD14+CD16+ monocytes with high expression of IL-6 and accelerate the inflammation Given that large amount of inflammatory cells infiltrations have been observed in lungs from severe COVID-19 patients7, 8, these aberrant pathogenic Th1 cells and inflammatory monocytes may enter the pulmonary circulation in huge numbers and play an immune damaging role to causing lung functional disability and quick mortality Our results demonstrate that excessive non-effective host immune responses by pathogenic T cells and inflammatory monocytes may associate with severe lung pathology Thus, we suggest that monoclonal antibodies targeting GM-CSF or interleukin 6 may be effective in blocking inflammatory storms and, therefore, be a promising treatment of severe COVID-19 patients

negative: Gold nanoparticle‐adjuvanted S protein induces a strong antigen‐specific IgG response against severe acute respiratory syndrome‐related coronavirus infection, but fails to induce protective antibodies and limit eosinophilic infiltration in lungs The spike (S) protein of coronavirus, which binds to cellular receptors and mediates membrane fusion for cell entry, is a candidate vaccine target for blocking coronavirus infection. However, some animal studies have suggested that inadequate immunization against severe acute respiratory syndrome coronavirus (SARS‐CoV) induces a lung eosinophilic immunopathology upon infection. The present study evaluated two kinds of vaccine adjuvants for use with recombinant S protein: gold nanoparticles (AuNPs), which are expected to function as both an antigen carrier and an adjuvant in immunization; and Toll‐like receptor (TLR) agonists, which have previously been shown to be an effective adjuvant in an ultraviolet‐inactivated SARS‐CoV vaccine. All the mice immunized with more than 0.5 µg S protein without adjuvant escaped from SARS after infection with mouse‐adapted SARS‐CoV; however, eosinophilic infiltrations were observed in the lungs of almost all the immunized mice. The AuNP‐adjuvanted protein induced a strong IgG response but failed to improve vaccine efficacy or to reduce eosinophilic infiltration because of highly allergic inflammatory responses. Whereas similar virus titers were observed in the control animals and the animals immunized with S protein with or without AuNPs, Type 1 interferon and pro‐inflammatory responses were moderate in the mice treated with S protein with and without AuNPs. On the other hand, the TLR agonist‐adjuvanted vaccine induced highly protective antibodies without eosinophilic infiltrations, as well as Th1/17 cytokine responses. The findings of this study will support the development of vaccines against severe pneumonia‐associated coronaviruses.

negative: Mucosal immunization with recombinant adenoviruses: induction of immunity and protection of cotton rats against respiratory bovine herpesvirus type 1 infection. To facilitate the evaluation of vaccines against bovine herpesvirus type 1 (BHV-1), a cotton rat model of intranasal (i.n.) BHV-1 infection was established. Cotton rat lung cells were similar to bovine cells in their ability to support BHV-1 replication in vitro. Furthermore, i.n. inoculation of cotton rats with BHV-1 resulted in pulmonary lesions comparable to BHV-1 infection in cattle. Using this model, the potential of i.n. and gastrointestinal (g.i.) immunization was examined with recombinant human adenoviruses expressing glycoprotein D (gD) of BHV-1 to induce protective immunity against BHV-1. The replication-competent virus (gD-dE3) was more efficient than the replication-defective virus (gD-dE1E3) in inducing gD-specific antibody in the serum and in the respiratory tract. Furthermore, i.n. immunization with gD-dE3 stimulated antigen-specific antibody-secreting cells in the lung 12 weeks following immunization. Protection against BHV-1 challenge correlated with gD-specific antibody levels such that i.n. immunization with gD-dE3 conferred complete protection, while g.i. immunization conferred only partial protection of the lungs of most animals against BHV-1 challenge. In comparison, immunization with gD-dE1E3 by either route resulted in only a partial reduction of BHV-1 titre in the respiratory tract. The results obtained demonstrate that mucosal immunization with replication-competent recombinant adenovirus expressing gD of BHV-1 can induce immunity and protection against BHV-1 challenge.

negative: Healthcare Personnel Exposure to a Patient with Asymptomatic SARS-CoV2 Infection during a Prolonged Surgical Intervention There is ongoing debate regarding the role of aerosols in the transmission of SARS-CoV2 in the healthcare environment. Here we report a case in which multiple operating room healthcare providers were exposed to a patient with asymptomatic SARS-CoV2 infection during a prolonged orthopedic surgical intervention and had no evidence of COVID-19 during the 14-day post-exposure period.

negative: Coronaviruses post-SARS: Update on replication and pathogenesis While coronaviruses were first identified nearly 60 years ago, they received notoriety in 2003 when one of their members was identified as the etiological agent of the Severe Acute Respiratory Syndrome (SARS-CoV) 1. Previously these viruses were known to be important agents of respiratory and enteric infections of domestic and companion animals and to cause approximately 15% of all cases of the common cold. This Review focuses on recent advances in our understanding of the mechanisms of coronavirus replication, interactions with the host immune response and disease pathogenesis and highlights the recent identification of numerous novel coronaviruses and the propensity of this virus family to cross species barriers.

negative: Cats, coronaviruses and coronavirus antibody tests Feline infectious peritonitis and other coronavirus infections of cats are briefly reviewed. Interpretation and applications of feline coronavirus antibody tests are described, and general recommendations are provided for practitioners. Some of the major unresolved questions regarding coronavirus infections of cats are delineated.

negative: Some latest achievements in immunology research Immunology has become as an attractive discipline of biomedical science in the 21st century, integrated with the rapid development of molecular biology, cell biology, structural biology, genetics and other branches in life sciences. A special issue of Sci China Life Sci was published in February 2010 to highlight recent progresses in immunology. Six review articles focusing on various specific topics were contributed by leading scientists who work in respective fields of immunology. Some progresses of immunology research in China are also described.

negative: Immunization of pregnant gilts with PRCV induces lactogenic immunity for protection of nursing piglets from challenge with TGEV Abstract The level of passive protection against transmissible gastroenteritis virus (TGEV) was evaluated by experimentally infecting 12 pregnant gilts with different doses of porcine respiratory coronavirus (PRCV) and challenging their litters at 4 days of age. An overall survival rate of 70% was found for piglets nursing the 12 PRCV-infected gilts, compared to a 16% survival rate for piglets of nine uninfected control gilts. Six of the PRCV-infected gilts had adequate levels of immunity to resist infection with TGEV following the challenge of their litters. These six completely immuned gilts also solidly protected their litters from TGEV as shown by a 96% piglet survival rate through weaning at 3 weeks of age. The results suggest that respiratory infection with PRCV induces a substantial degree of protective lactogenic immunity against TGEV.

negative: Potential Therapeutic Targeting of Coronavirus Spike Glycoprotein Priming Processing of certain viral proteins and bacterial toxins by host serine proteases is a frequent and critical step in virulence. The coronavirus spike glycoprotein contains three (S1, S2, and S2′) cleavage sites that are processed by human host proteases. The exact nature of these cleavage sites, and their respective processing proteases, can determine whether the virus can cross species and the level of pathogenicity. Recent comparisons of the genomes of the highly pathogenic SARS-CoV2 and MERS-CoV, with less pathogenic strains (e.g., Bat-RaTG13, the bat homologue of SARS-CoV2) identified possible mutations in the receptor binding domain and in the S1 and S2′ cleavage sites of their spike glycoprotein. However, there remains some confusion on the relative roles of the possible serine proteases involved for priming. Using anthrax toxin as a model system, we show that in vivo inhibition of priming by pan-active serine protease inhibitors can be effective at suppressing toxicity. Hence, our studies should encourage further efforts in developing either pan-serine protease inhibitors or inhibitor cocktails to target SARS-CoV2 and potentially ward off future pandemics that could develop because of additional mutations in the S-protein priming sequence in coronaviruses.

negative: Should scientists infect healthy people with the coronavirus to test vaccines?

negative: Development of Vaccines and Passive Immunotherapy Against Sars Coronavirus Using Mouse and Scid-PBL/hu Mouse Models We have investigated novel vaccines strategies against severe acute respiratory syndrome (SARS) CoV infection using cDNA constructs encoding the structural antigens; spike (S), membrane (M), envelope (E), or nucleocapsid (N) protein, derived from SARS CoV (strain HKU39849, TW1, or FFM-1). As SARS-CoV is thought to infect the alveolar epithelial cell of the lung,in the present study, a type II alveolar epithelial cell clone, T7, was used to analyze the mechanism of CTL against SARS CoV membrane antigens. Mice vaccinated with SARS CoV (N) DNA or (M) DNA using pcDNA 3.1 (+) plasmid vector showed T-cell immune responses (CTL induction and proliferation) against type II alveolar epithelial cells (T7) transfected with SARS (N) or (M) DNA, respectively. To determine whether these DNA vaccines could induce T-cell immune responses in humans as well as in mice, SCID-PBL/hu mice were immunized with these DNA vaccines. PBL from healthy human volunteers were administered i.p. into IL-2 receptor gamma-chain-disrupted NOD-SCID mice [IL-2R(-/-) NOD-SCID]. SCID-PBL/hu mice thus constructed can be used to analyze the human immune response in vivo. The SCID-PBL/hu mice were immunized with SARS (N) DNA or (M) DNA and analyzed for a human T-cell immune response. The M DNA vaccine enhanced CTL activity and proliferation in the presence of M peptide in SCID-PBL/hu mice. Furthermore, the SARS N DNA vaccine induced CTL activity (IFN-gamma production by recombinant N protein or N protein-pulsed autologous B blast cells) and proliferation of spleen cells in SCID-PBL/hu mice. These results, demonstrate that SARS M and N DNA vaccines induced human CTL and human T-cell proliferative responses. On the other hand, we have developed SARS DNA vaccines that induce human neutralizing antibodies and human monoclonal antibodies against SARS CoV. Transgenic mice expressing SARS-CoV receptor (angiotensin converting enzyme 2) are also under development. These vaccines are expected to induce immune responses specific for SARS CoV in human and should provide useful tool for development of protective vaccines.

negative: Inhibition of SARS-CoV-2 infection (previously 2019-nCoV) by a highly potent pan-coronavirus fusion inhibitor targeting its spike protein that harbors a high capacity to mediate membrane fusion The recent outbreak of coronavirus disease (COVID-19) caused by SARS-CoV-2 infection in Wuhan, China has posed a serious threat to global public health. To develop specific anti-coronavirus therapeutics and prophylactics, the molecular mechanism that underlies viral infection must first be confirmed. Therefore, we herein used a SARS-CoV-2 spike (S) protein-mediated cell-cell fusion assay and found that SARS-CoV-2 showed plasma membrane fusion capacity superior to that of SARS-CoV. We solved the X-ray crystal structure of six-helical bundle (6-HB) core of the HR1 and HR2 domains in SARS-CoV-2 S protein S2 subunit, revealing that several mutated amino acid residues in the HR1 domain may be associated with enhanced interactions with HR2 domain. We previously developed a pan-coronavirus fusion inhibitor, EK1, which targeted HR1 domain and could inhibit infection by divergent human coronaviruses tested, including SARS-CoV and MERS-CoV. We then generated a series of lipopeptides and found that the EK1C4 was the most potent fusion inhibitor against SARS-CoV-2 S protein-mediated membrane fusion and pseudovirus infection with IC50s of 1.3 and 15.8 nM, about 241- and 149-fold more potent than that of EK1 peptide, respectively. EK1C4 was also highly effective against membrane fusion and infection of other human coronavirus pseudoviruses tested, including SARS-CoV and MERS-CoV, as well as SARSr-CoVs, potently inhibiting replication of 4 live human coronaviruses, including SARS-CoV-2. Intranasal application of EK1C4 before or after challenge with HCoV-OC43 protected mice from infection, suggesting that EK1C4 could be used for prevention and treatment of infection by currently circulating SARS-CoV-2 and emerging SARSr-CoVs.

negative: Knowledge synthesis from 100 million biomedical documents augments the deep expression profiling of coronavirus receptors The COVID-19 pandemic demands assimilation of all available biomedical knowledge to decode its mechanisms of pathogenicity and transmission. Despite the recent renaissance in unsupervised neural networks for decoding unstructured natural languages, a platform for the real-time synthesis of the exponentially growing biomedical literature and its comprehensive triangulation with deep omic insights is not available. Here, we present the nferX platform for dynamic inference from over 45 quadrillion possible conceptual associations extracted from unstructured biomedical text, and their triangulation with Single Cell RNA-sequencing based insights from over 25 tissues. Using this platform, we identify intersections between the pathologic manifestations of COVID-19 and the comprehensive expression profile of the SARS-CoV-2 receptor ACE2. We find that tongue keratinocytes, airway club cells, and ciliated cells are likely underappreciated targets of SARS-CoV-2 infection, in addition to type II pneumocytes and olfactory epithelial cells. We further identify mature small intestinal enterocytes as a possible hotspot of COVID-19 fecal-oral transmission, where an intriguing maturation-correlated transcriptional signature is shared between ACE2 and the other coronavirus receptors DPP4 (MERS-CoV) and ANPEP (α-coronavirus). This study demonstrates how a holistic data science platform can leverage unprecedented quantities of structured and unstructured publicly available data to accelerate the generation of impactful biological insights and hypotheses. The nferX Platform Single-cell resource - https://academia.nferx.com/

negative: On the origin and continuing evolution of SARS-CoV-2 The SARS-CoV-2 epidemic started in late December 2019 in Wuhan, China, and has since impacted a large portion of China and raised major global concern. Herein, we investigated the extent of molecular divergence between SARS-CoV-2 and other related coronaviruses. Although we found only 4% variability in genomic nucleotides between SARS-CoV-2 and a bat SARS-related coronavirus (SARSr-CoV; RaTG13), the difference at neutral sites was 17%, suggesting the divergence between the two viruses is much larger than previously estimated. Our results suggest that the development of new variations in functional sites in the receptor-binding domain (RBD) of the spike seen in SARS-CoV-2 and viruses from pangolin SARSr-CoVs are likely caused by mutations and natural selection besides recombination. Population genetic analyses of 103 SARS-CoV-2 genomes indicated that these viruses evolved into two major types (designated L and S), that are well defined by two different SNPs that show nearly complete linkage across the viral strains sequenced to date. Although the L type (∼70%) is more prevalent than the S type (∼30%), the S type was found to be the ancestral version. Whereas the L type was more prevalent in the early stages of the outbreak in Wuhan, the frequency of the L type decreased after early January 2020. Human intervention may have placed more severe selective pressure on the L type, which might be more aggressive and spread more quickly. On the other hand, the S type, which is evolutionarily older and less aggressive, might have increased in relative frequency due to relatively weaker selective pressure. These findings strongly support an urgent need for further immediate, comprehensive studies that combine genomic data, epidemiological data, and chart records of the clinical symptoms of patients with coronavirus disease 2019 (COVID-19).

negative: The sequence of human ACE2 is suboptimal for binding the S spike protein of SARS coronavirus 2 The rapid and escalating spread of SARS coronavirus 2 (SARS-CoV-2) poses an immediate public health emergency. The viral spike protein S binds ACE2 on host cells to initiate molecular events that release the viral genome intracellularly. Soluble ACE2 inhibits entry of both SARS and SARS-2 coronaviruses by acting as a decoy for S binding sites, and is a candidate for therapeutic, prophylactic and diagnostic development. Using deep mutagenesis, variants of ACE2 are identified with increased binding to the receptor binding domain of S. Mutations are found across the interface, in the N90-glycosylation motif, and at buried sites where they are predicted to enhance local folding and presentation of the interaction epitope. When single substitutions are combined, large increases in binding can be achieved. The mutational landscape offers a blueprint for engineering high affinity proteins and peptides that block receptor binding sites on S to meet this unprecedented challenge.

negative: Broad anti-coronaviral activity of FDA approved drugs against SARS-CoV-2 in vitro and SARS-CoV in vivo SARS-CoV-2 emerged in China at the end of 2019 and has rapidly become a pandemic with roughly 2.7 million recorded COVID-19 cases and greater than 189,000 recorded deaths by April 23rd, 2020 (www.WHO.org). There are no FDA approved antivirals or vaccines for any coronavirus, including SARS-CoV-2. Current treatments for COVID-19 are limited to supportive therapies and off-label use of FDA approved drugs. Rapid development and human testing of potential antivirals is greatly needed. A quick way to test compounds with potential antiviral activity is through drug repurposing. Numerous drugs are already approved for human use and subsequently there is a good understanding of their safety profiles and potential side effects, making them easier to fast-track to clinical studies in COVID-19 patients. Here, we present data on the antiviral activity of 20 FDA approved drugs against SARS-CoV-2 that also inhibit SARS-CoV and MERS-CoV. We found that 17 of these inhibit SARS-CoV-2 at a range of IC50 values at non-cytotoxic concentrations. We directly follow up with seven of these to demonstrate all are capable of inhibiting infectious SARS-CoV-2 production. Moreover, we have evaluated two of these, chloroquine and chlorpromazine, in vivo using a mouse-adapted SARS-CoV model and found both drugs protect mice from clinical disease.

negative: Coronavirus disease 2019 (COVID-19): current status and future perspectives ABSTRACT Coronavirus disease 2019 (COVID-19) originated in the city of Wuhan, Hubei Province, Central China, and has spread quickly to 72 countries to date. COVID-19 is caused by a novel coronavirus, named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) [previously provisionally known as 2019 novel coronavirus (2019-nCoV)]. At present, the newly identified SARS-CoV-2 has caused a large number of deaths with tens of thousands of confirmed cases worldwide, posing a serious threat to public health. However, there are no clinically approved vaccines or specific therapeutic drugs available for COVID-19. Intensive research on the newly emerged SARS-CoV-2 is urgently needed to elucidate the pathogenic mechanisms and epidemiological characteristics and to identify potential drug targets, which will contribute to the development of effective prevention and treatment strategies. Hence, this review will focus on recent progress regarding the structure of SARS-CoV-2 and the characteristics of COVID-19, such as the aetiology, pathogenesis and epidemiological characteristics.

negative: Suppression of innate antiviral response by severe acute respiratory syndrome coronavirus M protein is mediated through the first transmembrane domain Coronaviruses have developed various measures to evade innate immunity. We have previously shown that severe acute respiratory syndrome (SARS) coronavirus M protein suppresses type I interferon (IFN) production by impeding the formation of functional TRAF3-containing complex. In this study, we demonstrate that the IFN-antagonizing activity is specific to SARS coronavirus M protein and is mediated through its first transmembrane domain (TM1) located at the N terminus. M protein from human coronavirus HKU1 does not inhibit IFN production. Whereas N-linked glycosylation of SARS coronavirus M protein has no influence on IFN antagonism, TM1 is indispensable for the suppression of IFN production. TM1 targets SARS coronavirus M protein and heterologous proteins to the Golgi apparatus, yet Golgi localization is required but not sufficient for IFN antagonism. Mechanistically, TM1 is capable of binding with RIG-I, TRAF3, TBK1 and IKKε, and preventing the interaction of TRAF3 with its downstream effectors. Our work defines the molecular architecture of SARS coronavirus M protein required for suppression of innate antiviral response.

negative: Colostrum Antibodies, Egg Antibodies and Monoclonal Antibodies Providing Passive Immunity for Animals Passive immunity can be provided to animals by several sources of antibodies including from colostrum, avian eggs, and monoclonal sources. These antibodies have been shown protect production and companion animals from a number of pathogens. This chapter reviews the immune system for the principles of immune response to antigens and the synthesis of immunoglobulins of the five classes of antibodies in the body. Colostrum antibodies are described for passive immunity protection in animals such as calves. Chicken egg antibodies are another source of antibodies for passive immunity. Therapeutic monoclonal antibodies are also used to provide passive immunity in the veterinary field.

negative: Feline immunodeficiency virus: A brief review Abstract Feline immunodeficiency virus (FIV), previously known as feline T-lymphotropic lentivirus (FTLV), was first described by Pedersen et al. (1987) who isolated the virus from cats with a variety of clinical signs suggestive of immunodeficiency. Since then FIV has become one of the most studied feline viruses, not least because of its similarity to human immunodeficiency viruses (HIV) which cause acquired immunodeficiency syndrome (AIDS) in man.

negative: Coronaviruses Coronaviruses of humans were first identified more than 60 years ago from individuals with respiratory infections, mainly mild. Two different viruses, 229E and OC43 were initially recognized. Because of difficulty in isolating them using standard techniques, many of the early studies of their occurrence were seroepidemiologic. They were confirmed to be worldwide in distribution, and, in the North Temperate Zone, mainly occurring in the winter season. With the development of the reverse transcriptase polymerase chain reaction (PCR) technique, two additional distinct viruses have been identified, HKU1 and NL63. The four viruses have now been recognized as important in the etiology of common respiratory infections, second only to the rhinoviruses. In 2002, a previously unrecognized betacoronavirus emerged from a zoonotic reservoir in Southern China and spread during the following year to several major cities of the world. The resulting illness was termed Severe Acute Respiratory Syndrome (SARS) because of its potential lethality. More than 8,000 probable cases were reported during 2003, mainly from Hong Kong and mainland China, producing social and economic disruption in those areas affected. A constant feature of the outbreak was the importance of nosocomial spread. In spite of an estimated basic reproductive number higher than influenza, the outbreak was ended, in large part because of control of in-hospital transmission. In 2012, another betacoronavirus has emerged in the Arabian peninsula which is producing a somewhat similar illness, termed Middle East Respiratory Syndrome (MERS), also marked by extensive nosocomial transmission. The outcome of this emergence is currently unknown.

negative: Pulmonary embolism in COVID-19. When nothing is what it seems

negative: Inferring Infection Patterns Based on a Connectivity Map of Host Transcriptional Responses Host responses to infections represent an important pathogenicity determiner, and delineation of host responses can elucidate pathogenesis processes and inform the development of anti-infection therapies. Low cost, high throughput, easy quantitation, and rich descriptions have made gene expression profiling generated by DNA microarrays an optimal approach for describing host transcriptional responses (HTRs). However, efforts to characterize the landscape of HTRs to diverse pathogens are far from offering a comprehensive view. Here, we developed an HTR Connectivity Map based on systematic assessment of pairwise similarities of HTRs to 50 clinically important human pathogens using 1353 gene-expression profiles generated from >60 human cells/tissues. These 50 pathogens were further partitioned into eight robust “HTR communities” (i.e., groups with more consensus internal HTR similarities). These communities showed enrichment in specific infection attributes and differential gene expression patterns. Using query signatures of HTRs to external pathogens, we demonstrated four distinct modes of HTR associations among different pathogens types/class, and validated the reliability of the HTR community divisions for differentiating and categorizing pathogens from a host-oriented perspective. These findings provide a first-generation HTR Connectivity Map of 50 diverse pathogens, and demonstrate the potential for using annotated HTR community to detect functional associations among infectious pathogens.

negative: Recombinant infectious bronchitis coronavirus H120 with the spike protein S1 gene of the nephropathogenic IBYZ strain remains attenuated but induces protective immunity Abstract Infectious bronchitis (IB) is a highly infectious viral disease responsible for major economic losses in the poultry industry. A reverse genetic vaccine is a safe, rapid, and effective method of achieving IB prevention and control. In this study, we constructed the recombinant strain, rH120-S1/YZ, using a reverse genetic system, based on the backbone of the H120 vaccine strain, with the S1 gene replaced with that of the QX-like nephropathogenic strain, ck/CH/IBYZ/2011, isolated in China. The results of dwarf chicken embryos, growth kinetics, and viral titration in the embryos demonstrated that the biological characteristics of the recombinant virus remained unchanged. Like the rH120-infected group and in contrast to the rIBYZ-infected group, no mortality, clinical signs, or lesions were observed in the lungs or kidneys of young chickens inoculated with rH120-S1/YZ. The viral loads in various tissues, cloacal, and oral swabs was lower in most types of samples, indicating that the rH120-S1/YZ strain was highly safe in chicks. Compared to rH120 vaccination group, when the efficacy of this strain was evaluated against the QX-like IBV strain, better protection, with 100% survival rate and no disease symptom or gross lesion was observed in the chickens vaccinated with rH120-S1/YZ. Increased levels of IBV-specific antibodies were detected in the serum of the rH120-S1/YZ-vaccinated animals 14 days post-vaccination. Collectively, our results suggest that the recombinant strain, rH120-S1/YZ, may represent a promising vaccine candidate against QX-like IBVs.

negative: Lactogenic immunity to transmissible gastroenteritis (TGE) of swine induced by the attenuated Nouzilly strain of TGE virus: neutralizing antibody classes and protection. An attenuated TGE coronavirus mutant (Nouzilly strain) relatively resistant to acidity and digestive enzymes was used for immunization of 11 seronegative pregnant sows, mainly by the oral route. Nouzilly strain is able to induce a protective lactogenic immunity in suckling piglets against severe virulent TGE challenge. However the level of neutralizing activity in serum and milk of vaccinated sows at the time of challenge exposure is not correlated with passive protection rate. Separation of the immunoglobulin classes bearing neutralizing activity in serum and milk from vaccinated sows, by ion-exchange chromatography, failed to demonstrate any relationship between antibody level of these fractions and passive protection rate of piglets. Our results suggest that IgA neutralizing antibodies present in milk are not the only parameters to consider to explain the lactogenic immunity induced by the Nouzilly strain given by oral route.

negative: DUSP1 regulates apoptosis and cell migration, but not the JIP1-protected cytokine response, during Respiratory Syncytial Virus and Sendai Virus infection The host antiviral response involves the induction of interferons and proinflammatory cytokines, but also the activation of cell death pathways, including apoptosis, to limit viral replication and spreading. This host defense is strictly regulated to eliminate the infection while limiting tissue damage that is associated with virus pathogenesis. Post-translational modifications, most notably phosphorylation, are key regulators of the antiviral defense implying an important role of protein phosphatases. Here, we investigated the role of the dual-specificity phosphatase 1 (DUSP1) in the host defense against human respiratory syncytial virus (RSV), a pathogenic virus of the Pneumoviridae family, and Sendai virus (SeV), a model virus being developed as a vector for anti-RSV vaccine. We found that DUSP1 is upregulated before being subjected to proteasomal degradation. DUSP1 does not inhibit the antiviral response, but negatively regulates virus-induced JNK/p38 MAPK phosphorylation. Interaction with the JNK-interacting protein 1 scaffold protein prevents dephosphorylation of JNK by DUSP1, likely explaining that AP-1 activation and downstream cytokine production are protected from DUSP1 inhibition. Importantly, DUSP1 promotes SeV-induced apoptosis and suppresses cell migration in RSV-infected cells. Collectively, our data unveils a previously unrecognized selective role of DUSP1 in the regulation of tissue damage and repair during infections by RSV and SeV.

negative: Structure, Expression, and Intracellular Localization of the SARS-CoV Accessory Proteins 7a and 7b

negative: Phosphatidylserine treatment relieves the block to retrovirus infection of cells expressing glycosylated virus receptors BACKGROUND: A major determinant of retrovirus host range is the presence or absence of appropriate cell-surface receptors required for virus entry. Often orthologs of functional receptors are present in a wide range of species, but amino acid differences can render these receptors non-functional. In some cases amino acid differences result in additional N-linked glycosylation that blocks virus infection. The latter block to retrovirus infection can be overcome by treatment of cells with compounds such as tunicamycin, which prevent the addition of N-linked oligosaccharides. RESULTS: We have discovered that treatment of cells with liposomes composed of phosphatidylserine (PS) can also overcome the block to infection mediated by N-linked glycosylation. Importantly, this effect occurs without apparent change in the glycosylation state of the receptors for these viruses. This effect occurs with delayed kinetics compared to previous results showing enhancement of virus infection by PS treatment of cells expressing functional virus receptors. CONCLUSION: We have demonstrated that PS treatment can relieve the block to retrovirus infection of cells expressing retroviral receptors that have been rendered non-functional by glycosylation. These findings have important implications for the current model describing inhibition of virus entry by receptor glycosylation.

negative: CORONAVIRUS VIRULENCE GENES WITH MAIN FOCUS ON SARS-CoV ENVELOPE GENE Coronavirus (CoV) infection is usually detected by cellular sensors, which trigger the activation of the innate immune system. Nevertheless, CoVs have evolved viral proteins that target different signaling pathways to counteract innate immune responses. Some CoV proteins act as antagonists of interferon (IFN) by inhibiting IFN production or signaling, aspects that are briefly addressed in this review. After CoV infection, potent cytokines relevant in controlling virus infections and priming adaptive immune responses are also generated. However, an uncontrolled induction of these proinflammatory cytokines can lead to pathogenesis and disease severity as described for SARS-CoV and MERS-CoV. The cellular pathways mediated by interferon regulatory factor (IRF)-3 and 7, activating transcription factor (ATF)-2/jun, activator protein (AP)-1, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), and nuclear factor of activated T cells (NF-AT), are the main drivers of the inflammatory response triggered after viral infections, with NF-κB pathway the most frequently activated. Key CoV proteins involved in the regulation of these pathways and the proinflammatory immune response are revisited in this manuscript. It has been shown that the envelope (E) protein plays a variable role in CoV morphogenesis, depending on the CoV genus, being absolutely essential in some cases (genus α CoVs such as TGEV, and genus β CoVs such as MERS-CoV), but not in others (genus β CoVs such as MHV or SARS-CoV). A comprehensive accumulation of data has shown that the relatively small E protein elicits a strong influence on the interaction of SARS-CoV with the host. In fact, after infection with viruses in which this protein has been deleted, increased cellular stress and unfolded protein responses, apoptosis, and augmented host immune responses were observed. In contrast, the presence of E protein activated a pathogenic inflammatory response that may cause death in animal models and in humans. The modification or deletion of different motifs within E protein, including the transmembrane domain that harbors an ion channel activity, small sequences within the middle region of the carboxy-terminus of E protein, and its most carboxy-terminal end, which contains a PDZ domain-binding motif (PBM) is sufficient to attenuate the virus. Interestingly, a comprehensive collection of SARS-CoVs in which these motifs have been modified elicited full and long-term protection even in old mice, making those deletion mutants promising vaccine candidates. These data indicate that despite its small size, E protein drastically influences the replication of CoVs and their pathogenicity. Although E protein is not essential for CoV genome replication or subgenomic mRNA synthesis, it affects virus morphogenesis, budding, assembly, intracellular trafficking, and virulence. In fact, E protein is responsible in a significant proportion of the inflammasome activation and the associated inflammation elicited by SARS-CoV in the lung parenchyma. This exacerbated inflammation causes edema accumulation leading to acute respiratory distress syndrome (ARDS) and, frequently, to the death of infected animal models or human patients.

negative: Coronavirus infections and type 2 diabetes-shared pathways with therapeutic implications Individuals with diabetes are at increased risk for bacterial, mycotic, parasitic and viral infections. The severe acute respiratory syndrome (SARS)-CoV2 (also referred to as COVID-19) coronavirus pandemic highlights the importance of understanding shared disease pathophysiology potentially informing therapeutic choices in individuals with Type 2 diabetes (T2D). Two coronavirus receptor proteins, Angiotensin Converting Enzyme 2 (ACE2) and Dipeptidyl Peptidase-4 (DPP4) are also established transducers of metabolic signals and pathways regulating inflammation, renal and cardiovascular physiology, and glucose homeostasis. Moreover, glucose-lowering agents such as the DPP4 inhibitors, widely used in subjects with T2D, are known to modify the biological activities of multiple immunomodulatory substrates. Here we review the basic and clinical science spanning the intersections of diabetes, coronavirus infections, ACE2, and DPP4 biology, highlighting clinical relevance and evolving areas of uncertainty underlying the pathophysiology and treatment of T2D in the context of coronavirus infection

negative: SARS vaccine based on a replication-defective recombinant vesicular stomatitis virus is more potent than one based on a replication-competent vector Abstract A SARS vaccine based on a live-attenuated vesicular stomatitis virus (VSV) recombinant expressing the SARS-CoV S protein provides long-term protection of immunized mice from SARS-CoV infection (Kapadia, S.U., Rose, J. K., Lamirande, E., Vogel, L., Subbarao, K., Roberts, A., 2005. Long-term protection from SARS coronavirus infection conferred by a single immunization with an attenuated VSV-based vaccine. Virology 340(2), 174–82.). Because it is difficult to obtain regulatory approval of vaccine based on live viruses, we constructed a replication-defective single-cycle VSV vector in which we replaced the VSV glycoprotein (G) gene with the SARS-CoV S gene. The virus was only able to infect cells when pseudotyped with the VSV G protein. We measured the effectiveness of immunization with the single-cycle vaccine in mice. We found that the vaccine given intramuscularly induced a neutralizing antibody response to SARS-CoV that was approximately ten-fold greater than that required for the protection from SARS-CoV infection, and significantly greater than that generated by the replication-competent vector expressing SARS-CoV S protein given by the same route. Our results, along with earlier studies showing potent induction of T-cell responses by single-cycle vectors, indicate that these vectors are excellent alternatives to live-attenuated VSV.

negative: Vaccination Against Coronaviruses In Domestic Animals Abstract The current pandemic of COVID-19 has set off an urgent search for an effective vaccine. This search may well benefit from the experiences of the animal health profession in the development and use of coronavirus vaccines in domestic animal species. These animal vaccines will in no way protect humans against COVID-19 but knowledge of the difficulties encountered in vaccinating animals may help avoid or minimize similar problems arising in humans. Diverse coronaviruses can infect the domestic species from dogs and cats, to cattle and pigs to poultry. Many of these infections are controlled by the routine vaccination. Thus, canine coronavirus vaccines are protective in puppies but the disease itself is mild and self-limiting. Feline coronavirus infections may be mild or may result in a lethal immune-mediated disease – feline infectious peritonitis. As a result, vaccination of domestic cats must seek to generated protective immunity without causing immune-mediated disease. Vaccines against bovine coronavirus are widely employed in cattle where they protect against enteric and respiratory disease in young calves. Two major livestock species suffer from economically significant and severe coronavirus diseases. Thus, pigs may be infected with six different coronaviruses, one of which, porcine epidemic diarrhea, has proven difficult to control despite the development of several innovative vaccines. Porcine epidemic diarrhea virus undergoes frequent genetic changes. Likewise, infectious bronchitis coronavirus causes an economically devastating disease of chickens. It too undergoes frequent genetic shifts and as a result, can only be controlled by extensive and repeated vaccination. Other issues that have been encountered in developing these animal vaccines include a relatively short duration of protective immunity, and a lack of effectiveness of inactivated vaccines. On the other hand, they have been relatively cheap to make and lend themselves to mass vaccination procedures.

negative: Feline and Canine Coronaviruses: Common Genetic and Pathobiological Features A new human coronavirus responsible for severe acute respiratory syndrome (SARS) was identified in 2003, which raised concern about coronaviruses as agents of serious infectious disease. Nevertheless, coronaviruses have been known for about 50 years to be major agents of respiratory, enteric, or systemic infections of domestic and companion animals. Feline and canine coronaviruses are widespread among dog and cat populations, sometimes leading to the fatal diseases known as feline infectious peritonitis (FIP) and pantropic canine coronavirus infection in cats and dogs, respectively. In this paper, different aspects of the genetics, host cell tropism, and pathogenesis of the feline and canine coronaviruses (FCoV and CCoV) will be discussed, with a view to illustrating how study of FCoVs and CCoVs can improve our general understanding of the pathobiology of coronaviruses.

negative: The interface of animal and human vaccines

negative: Immunological aspects of the efficiency of protectotype vaccination strategy against chicken infectious bronchitis BACKGROUND: One of the most commonly applied protectotype vaccination protocol against infectious bronchitis (IB) in broiler chickens in the EU is simultaneous or alternate use of Ma5 and 4/91 vaccine strains. After IB vaccination and infection, systemic and upper respiratory tract (URT), humoral and cell-mediated immunity (CMI), are stimulated. The level of this stimulation correlates with the level of protection against IB. RESULTS: We’ve investigated the development of URT and systemic, cell-mediated and humoral immunity in commercial broiler chickens vaccinated with Ma5 and/or 4/91 strains at hatch day. We’ve demonstrated that the group vaccinated with Ma5 and 4/91 strain simultaneously developed the most desirable immunity which reflects the level of CD8(+) T cells stimulation in spleen and Harderian gland, as well as the level of IgA and IgY in URT washings and serum and their cross-reactivity with 7 IBV strains. CONCLUSIONS: Although we did not demonstrate directly why Ma5 + 4/91 protocol is so efficient it seems that it combines the benefits of monovalent vaccination with either Ma5 or 4/91 and while Ma5 seems to stimulate CMI more efficiently, the 4/91 strain generates a wider spectrum of immune system cross-reactivity and higher URT IgA production.

negative: ADHD management during the COVID-19 pandemic: guidance from the European ADHD Guidelines Group

negative: Should COVID-19 Concern Nephrologists? Why and to What Extent? The Emerging Impasse of Angiotensin Blockade Here, we review the most recent findings on the effects of SARS-CoV-2 infection on kidney diseases, including acute kidney injury, and examine the potential effects of ARBs on the outcomes of patients with COVID-19. Lastly, we discuss the clinical management of COVID-19 patients with existing chronic renal disorders, particularly those in dialysis and with kidney transplants.

negative: Genotyping coronavirus SARS-CoV-2: Methods and implications Abstract The emerging global infectious COVID-19 disease by novel Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) presents critical threats to global public health and the economy since it was identified in late December 2019 in China. The virus has gone through various pathways of evolution. To understand the evolution and transmission of SARS-CoV-2, genotyping of virus isolates is of great importance. This study presents an accurate method for effectively genotyping SARS-CoV-2 viruses using complete genomes. The method employs the multiple sequence alignments of the genome isolates with the SARS-CoV-2 reference genome. The single-nucleotide polymorphism (SNP) genotypes are then measured by Jaccard distances to track the relationship of virus isolates. The genotyping analysis of SARS-CoV-2 isolates from the globe reveals that specific multiple mutations are the predominated mutation type during the current epidemic. The proposed method serves an effective tool for monitoring and tracking the epidemic of pathogenic viruses in their global and local genetic variations. The genotyping analysis shows that the genes encoding the S proteins and RNA polymerase, RNA primase, and nucleoprotein, undergo frequent mutations. These mutations are critical for vaccine development in disease control.

negative: Early detection of SARS-CoV-2 antibodies in COVID-19 patients as a serologic marker of infection BACKGROUND: Thousands of medical staff had been infected with SARS-CoV-2 virus with hundreds of deaths reported. Such loss could be prevented if there is a serologic assay for SARS-CoV-2-specific antibodies for serological surveillance of its infection at the early stage of disease. METHODS: Using CHO cell expressed full length SARS-CoV-2 S1 protein as capturing antigen, a COVID-19/SARS-CoV-2 S1 serology ELISA kit was developed and validated with negative samples collected prior to the outbreaks or during the outbreak, and positive samples from patients confirmed with COVID-19. RESULTS: The specificity of the ELISA kit was 97.5%, as examined against total 412 normal human samples. The sensitivity was 97.1% by testing against 69 samples from hospitalized and/or recovered COVID-19 patients. The overall accuracy rate reached 97.3%. The assay was able to detect SARS-CoV-2 antibody on day one after the onset of COVID-19 disease. The average antibody levels increased during the hospitalization and after been discharged for two weeks. SARS-CoV-2 antibodies were detected in 28 out of 276 asymptomatic medical staff and one out of five nucleic acid test-negative “Close contacts” of COVID-19 patient. CONCLUSION: With the assays developed here, we can screen medical staff, in-coming patients, passengers and people who are in close contact with the confirmed patients to identify the “innocent viral spreaders”, protect the medical staff and stop the further spreading of the virus.

negative: Insight into 2019 novel coronavirus — an updated intrim review and lessons from SARS-CoV and MERS-CoV Abstract Background The rapid spread of the coronavirus disease 2019 (COVID-19), caused by a zoonotic beta-coronavirus entitled 2019 novel coronavirus (2019-nCoV), has become a global threat. Awareness of the biological features of 2019-nCoV should be updated in time and needs to be comprehensively summarized to help optimize control measures and make therapeutic decisions. Methods Based on recently published literatures, official documents and selected up-to-date preprint studies, we reviewed the virology and origin, epidemiology, clinical manifestations, pathology and treatment of 2019-nCoV infection, in comparison with severe acute respiratory syndrome coronavirus (SARS-CoV) and middle east respiratory syndrome coronavirus (MERS-CoV) infection. Results The genome of 2019-nCoV partially resembled SARS-CoV and MERS-CoV, and indicating a bat origin. The COVID-19 generally had a high reproductive number, a long incubation period, a short serial interval and a low case fatality rate (much higher in patients with comorbidities) than SARS and MERS. Clinical presentation and pathology of COVID-19 greatly resembled SARS and MERS, with less upper respiratory and gastrointestinal symptoms, and more exudative lesions in post-mortems. Potential treatments included remdesivir, chloroquine, tocilizumab, convalescent plasma and vaccine immunization (when possible). Conclusion The initial experience from the current pandemic and lessons from the previous two pandemics can help improve future preparedness plans and combat disease progression.

negative: Towards new TB vaccines Mycobacterium tuberculosis remains the leading cause of death attributed to a single infectious organism. Bacillus Calmette-Guerin (BCG), the standard vaccine against M. tuberculosis, is thought to prevent only 5% of all vaccine-preventable deaths due to tuberculosis, thus an alternative vaccine is required. One of the principal barriers to vaccine development against M. tuberculosis is the complexity of the immune response to infection, with uncertainty as to what constitutes an immunological correlate of protection. In this paper, we seek to give an overview of the immunology of M. tuberculosis infection, and by doing so, investigate possible targets of vaccine development. This encompasses the innate, adaptive, mucosal and humoral immune systems. Though MVA85A did not improve protection compared with BCG alone in a large-scale clinical trial, the correlates of protection this has revealed, in addition to promising results from candidate such as VPM1002, M72/ASO1E and H56:IC31 point to a brighter future in the field of TB vaccine development.

negative: Do checkpoint inhibitors compromise the cancer patients' immunity and increase the vulnerability to COVID-19 infection? The severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) has been declared a pandemic by the WHO that claimed the lives of thousands of people within a few months. Cancer patients represent a vulnerable population due to the acquired immunodeficiency associated with anti-cancer therapy. Immune checkpoint inhibitors have largely impacted the prognosis of a multitude of malignancies with significant improvement in survival outcomes and a different, tolerable toxicity profile. In this paper, we assess the safety of ICI administration in cancer patients during the coronavirus pandemic in order to guide the usage of these highly efficacious agents.

negative: Development and Evaluation of an AI System for COVID-19 Early detection of COVID-19 based on chest CT will enable timely treatment of patients and help control the spread of the disease. With rapid spreading of COVID-19 in many countries, however, CT volumes of suspicious patients are increasing at a speed much faster than the availability of human experts. Here, we propose an artificial intelligence (AI) system for fast COVID-19 diagnosis with an accuracy comparable to experienced radiologists. A large dataset was constructed by collecting 970 CT volumes of 496 patients with confirmed COVID-19 and 260 negative cases from three hospitals in Wuhan, China, and 1,125 negative cases from two publicly available chest CT datasets. Trained using only 312 cases, our diagnosis system, which is based on deep convolutional neural network, is able to achieve an accuracy of 94.98%, an area under the receiver operating characteristic curve (AUC) of 97.91%, a sensitivity of 94.06%, and a specificity of 95.47% on an independent external verification dataset of 1,255 cases. In a reader study involving five radiologists, only one radiologist is slightly more accurate than the AI system. The AI system is two orders of magnitude faster than radiologists and the code is available at https://github.com/ChenWWWeixiang/diagnosis_covid19.

negative: MyD88 Is Required for Protection from Lethal Infection with a Mouse-Adapted SARS-CoV A novel human coronavirus, SARS-CoV, emerged suddenly in 2003, causing approximately 8000 human cases and more than 700 deaths worldwide. Since most animal models fail to faithfully recapitulate the clinical course of SARS-CoV in humans, the virus and host factors that mediate disease pathogenesis remain unclear. Recently, our laboratory and others developed a recombinant mouse-adapted SARS-CoV (rMA15) that was lethal in BALB/c mice. In contrast, intranasal infection of young 10-week-old C57BL/6 mice with rMA15 results in a nonlethal infection characterized by high titer replication within the lungs, lung inflammation, destruction of lung tissue, and loss of body weight, thus providing a useful model to identify host mediators of protection. Here, we report that mice deficient in MyD88 (MyD88(−/−)), an adapter protein that mediates Toll-like receptor (TLR), IL-1R, and IL-18R signaling, are far more susceptible to rMA15 infection. The genetic absence of MyD88 resulted in enhanced pulmonary pathology and greater than 90% mortality by day 6 post-infection. MyD88(−/−) mice had significantly higher viral loads in lung tissue throughout the course of infection. Despite increased viral loads, the expression of multiple proinflammatory cytokines and chemokines within lung tissue and recruitment of inflammatory monocytes/macrophages to the lung was severely impaired in MyD88(−/−) mice compared to wild-type mice. Furthermore, mice deficient in chemokine receptors that contribute to monocyte recruitment to the lung were more susceptible to rMA15-induced disease and exhibited severe lung pathology similar to that seen in MyD88(−/−)mice. These data suggest that MyD88-mediated innate immune signaling and inflammatory cell recruitment to the lung are required for protection from lethal rMA15 infection.

negative: Mouse Hepatitis Virus This chapter attempts to provide an overview of the important aspects of mouse hepatitis virus (MHV) experimental biology while emphasizing the virus as a naturally occurring mouse pathogen. Even this is complicated, as it is impossible to generalize with this virus, due to marked differences in the biologic behavior of the myriad virus strains, plus the marked effects of a large number of host factors. It is now known that the MHV group is represented by numerous variants that are constantly mutating, and that these viruses can be biologically separated into respiratory (polytropic) MHVs and enterotropic MHVs, with distinctly different patterns of tissue tropism. This dichotomy is emphasized for discussion, but biology is never absolute. Many of the early MHV isolations are made as a result of contamination of biological materials that correlated with their polytropic biologic behavior. Their stated tropisms frequently were the result of the investigators' research interests and many have therefore been subjected to selective passage that favors a particular tissue tropism. All MHV isolates are related genetically and antigenically, but isolates can be differentiated by genetic sequencing, cross-serum neutralization, or with monoclonal antibodies. Genetic and antigenic relationships are not predictive of biologic behavior.

negative: A Cross-Reactive Humanized Monoclonal Antibody Targeting Fusion Glycoprotein Function Protects Ferrets Against Lethal Nipah Virus and Hendra Virus Infection BACKGROUND: Nipah virus (NiV) and Hendra virus (HeV) are zoonotic paramyxoviruses that cause severe disease in both animals and humans. There are no approved vaccines or treatments for use in humans; however, therapeutic treatment of both NiV and HeV infection in ferrets and nonhuman primates with a cross-reactive, neutralizing human monoclonal antibody (mAb), m102.4, targeting the G glycoprotein has been demonstrated. In a previous study, we isolated, characterized, and humanized a cross-reactive, neutralizing anti-F mAb (h5B3.1). The mAb h5B3.1 blocks the required F conformational change needed to facilitate membrane fusion and virus infection, and the epitope recognized by h5B3.1 has been structurally defined; however, the efficacy of h5B3.1 in vivo is unknown. METHODS: The postinfection antiviral activity of h5B3.1 was evaluated in vivo by administration in ferrets after NiV and HeV virus challenge. RESULTS: All subjects that received h5B3.1 from 1 to several days after infection with a high-dose, oral-nasal virus challenge were protected from disease, whereas all controls died. CONCLUSIONS: This is the first successful postexposure antibody therapy for NiV and HeV using a humanized cross-reactive mAb targeting the F glycoprotein, and the findings suggest that a combination therapy targeting both F and G should be evaluated as a therapy for NiV/HeV infection.

negative: Human leukocyte antigen susceptibility map for SARS-CoV-2 We probe how genetic variability across the three major histocompatibility complex (MHC) class I genes (human leukocyte antigen [HLA] A, B, and C) may affect susceptibility to and severity of severe acute respiratory syndrome 2 (SARS-CoV-2), the virus responsible for coronavirus disease 2019 (COVID-19). We execute a comprehensive in silico analysis of viral peptide-MHC class I binding affinity across all known HLA -A, -B, and -C genotypes for all SARS-CoV-2 peptides. We further explore the potential for cross-protective immunity conferred by prior exposure to four common human coronaviruses. The SARS-CoV-2 proteome is successfully sampled and presented by a diversity of HLA alleles. However, we found that HLA-B*46:01 had the fewest predicted binding peptides for SARS-CoV-2, suggesting individuals with this allele may be particularly vulnerable to COVID-19, as they were previously shown to be for SARS (1). Conversely, we found that HLA-B*15:03 showed the greatest capacity to present highly conserved SARS-CoV-2 peptides that are shared among common human coronaviruses, suggesting it could enable cross-protective T-cell based immunity. Finally, we report global distributions of HLA types with potential epidemiological ramifications in the setting of the current pandemic.

negative: The demand for inpatient and ICU beds for COVID-19 in the US: lessons from Chinese cities BACKGROUND: Sustained spread of SARS-CoV-2 has happened in major US cities. Capacity needs in Chinese cities could inform the planning of local healthcare resources. METHODS: We described the intensive care unit (ICU) and inpatient bed needs for confirmed COVID-19 patients in two Chinese cities (Wuhan and Guangzhou) from January 10 to February 29, 2020, and compared the timing of disease control measures in relation to the timing of SARS-CoV-2 community spread. We estimated the peak ICU bed needs in US cities if a Wuhan-like outbreak occurs. RESULTS: In Wuhan, strict disease control measures were implemented six weeks after sustained local transmission of SARS-CoV-2. Between January 10 and February 29, COVID-19 patients accounted for an average of 637 ICU patients and 3,454 serious inpatients on each day. During the epidemic peak, 19,425 patients (24.5 per 10,000 adults) were hospitalized, 9,689 (12.2 per 10,000 adults) were considered to be in serious condition, and 2,087 patients (2.6 per 10,000 adults) needed critical care per day. In Guangzhou, strict disease control measures were implemented within one week of case importation. Between January 24 and February 29, COVID-19 accounted for an average of 9 ICU patients and 20 inpatients on each day. During the epidemic peak, 15 patients were in critical condition, and 38 were classified as serious. If a Wuhan-like outbreak were to happen in a US city, the need for healthcare resources may be higher in cities with a higher prevalence of vulnerable populations. CONCLUSION: Even after the lockdown of Wuhan on January 23, the number of seriously ill COVID-19 patients continued to rise, exceeding local hospitalization and ICU capacities for at least a month. Plans are urgently needed to mitigate the effect of COVID-19 outbreaks on the local healthcare system in US cities.

negative: Chapter 13 Biology and Diseases of Cats Domestic cats (Felis cattus) comprise a small (2%) percentage of the non-rodent animals used in biomedical research. In 2011, 21,700 cats of a total 1,134,693 non-rodent animals were used in research (APHIS, 2011). According to the National Research Council Committee on Scientific and Humane Issues in the Use of Random Source Dogs and Cats in Research (National Research Council, 2009), peak use of cats occurred in 1974. Since that time, the number of cats used in research has fallen by 71%, with more than 98% of those cats being purpose bred for research. Cats are a U.S. Department of Agriculture (USDA) covered species with special housing requirements defined in the Animal Welfare Act and the Guide for the Care and Use of Laboratory Animals (NRC, 2011). At the request of congress, a committee of experts formed by the National Research Council examined the use of random source dogs and cats and concluded that obtaining dogs and cats from Class B dealers is not necessary for NIH funded research (National Research Council, 2009). While the number of cats used in biomedical research has declined, cats continue to contribute uniquely to biomedical science and are valuable research model for several disciplines, including aspects of neurology involved in locomotion and spinal trauma, retrovirus and zoonotic disease research, and for developing therapeutic strategies for inherited diseases.

negative: Ultrastructure and protein A-gold immunolabelling of HRT-18 cells infected with turkey enteric coronavirus Abstract The Minnesota strain of turkey enteric coronavirus (TCV) was propagated in HRT-18 cells, a cell line derived from human rectum adenocarcinoma. A productive non-cytopathic infection was established, without a previous adaptation, in these cells as shown by the specific hemagglutinating activity in cell culture supernatants. A post-embedding immunochemical technique, using specific antiserum directed against the original egg-adapted virus and colloidal-gold-labelled protein A as the electron-dense marker, was used for the identification of the virus and related antigens in the cells by electron microscopy. Budding of typical coronavirus particles, through intracytoplasmic membranes and accumulation of complete virus within cytoplasmic vesicles or the lumen of rough endoplasmic reticulum, were the main features of the viral morphogenesis. Late in infection, numerous progeny viral particles were shown at the outer surface of infected cells, but budding could not be demonstrated at this level. Two different types of surface projections were observed on the extracellular particles of this avian coronavirus. These morphological characteristics have been thus far described only for mammalian hemagglutinating coronaviruses.

negative: Fatalism in the context of COVID-19: Perceiving coronavirus as a death sentence predicts reluctance to perform recommended preventative behaviors() To manage the spread of coronavirus, health entities have urged the public to take preventative measures such as social distancing and handwashing. Yet, many appear reluctant to take these measures. Research is needed to understand factors underlying such reluctance, with the aim of developing targeted health interventions. We identify associating coronavirus with death as one such factor. 590 participants completed surveys in mid-March 2020, which included attitudes toward coronavirus, preventative behavioral intentions, and sociodemographic factors. Associating coronavirus with death negatively predicted intentions to perform preventative behaviors. Further, associating coronavirus with death was not evenly distributed throughout the sample and was related with a number of sociodemographic factors including age, race, and availability of sick leave. Following recommended preventative measures to slow the spread of coronavirus appears to relate to the degree to which people associate coronavirus with death. These findings can be used by public health researchers and practitioners to identify those for whom targeted health communication and interventions would be most beneficial, as well as to frame health messaging in ways that combat fatalism.

negative: Preparation and evaluation of anti-SARS coronavirus IgY from yolks of immunized SPF chickens Abstract Severe acute respiratory syndrome (SARS) is a recently discovered viral disease, characterized by fever, cough, acute fibrinous pneumonia and high infectivity. Specific pathogen-free (SPF) chickens were immunized with inactivated SARS coronavirus and their eggs were harvested at regular intervals. Yolk immunoglobulin (IgY) was extracted using the water dilution method, followed by further purification on a Sephadex G-75 column. SDS-polyacrylamide gel electrophoresis (SDS-PAGE), Western blot and neutralization test results showed that the IgY obtained was of a high purity and had a strong reactive activity with a neutralization titer of 1:640. Lyophilization and stability tests showed that lyophilized anti-SARS coronavirus IgY had promising physical properties, with no significant reduction in reactive activity and good thermal stability. All these data suggest that the anti-SARS coronavirus IgY could be a new useful biological product for specific antiviral therapy against SARS.

negative: Pangolins Harbor SARS-CoV-2-Related Coronaviruses The pandemic of coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 has posed a severe threat to global public health. Yet, the origin of SARS-CoV-2 remains mysterious. Several recent studies (e.g., Lam et al ., Xiao et al .) identified SARS-CoV-2-related viruses in pangolins, providing novel insights into the evolution and diversity of SARS-CoV-2-related viruses.

negative: Clinical exacerbation of SARS-CoV2 infection after fingolimod withdrawal The role of disease-modifying therapies in patients with autoimmune disorders during SARS-CoV2 infection is controversial. Immunocompromised patients could have a more severe COVID-19 disease, due to the absence of an adequate immune response against the SARS-CoV-2. However, therapies that act on immune response could play a protective role by dampening the cytokine release syndrome. Fingolimod is a drug used for immune therapy in patients with Multiple Sclerosis (MS) through the sequestration of activated lymphocytes in the lymph nodes. We report the case of a 57-year-old man with relapsing-remitting MS treated with fingolimod that showed a reactivation of COVID-19 with signs of hyperinflammation syndrome after fingolimod withdrawal. Our case suggests that discontinuation of fingolimod during COVID-19 could imply a worsening of SARS-CoV2 infection. This article is protected by copyright. All rights reserved.

negative: Guidelines for the management of surgical departments in non-uniform hospitals during the COVID-19 pandemic. In the last several weeks we have been witnessing the exponentially progressing pandemic SARS-CoV-2 coronavirus. As the number of people infected with SARS-CoV2 escalates, the problem of surgical management of patients requiring urgent surgery is increasing. Patients infected with SARS-CoV2 virus but with negative test results will appear in general hospitals and may pose a risk to other patients and hospital staff. Health care workers constitutes nearly 17% of infected population in Poland, therefore early identification of infected people becomes a priority to protect human resources and to ensure continuity of the access to a surgical care. Both surgical operations, and endoscopic procedures are considered as interventions with an increased risk of infection. Therefore, determining the algorithm becomes crucial for qualifying patients for surgical treatment, but also to stratify the risk of personnel being infected during surgery and to adequately protect staff. Each hospital should be logistically prepared for the need to perform urgent surgery on a patient with suspected or confirmed infection, including personal protective equipment. Limited availability of the equipment, working under pressure and staff shortages in addition to a highly contagious pathogen necessitate a pragmatic management of human resources in health care. Instant synchronized action is needed, and clear uniform guidelines are essential for the healthcare system to provide citizens with the necessary surgical care while protecting both patients, and staff. This document presents current recommendations regarding surgery during the COVID-19 pandemic in Poland.

negative: [Strategies for vaccine development of COVID-19]. An epidemic of acute respiratory syndrome in humans, which appeared in Wuhan, China in December 2019, was caused by a novel coronavirus (SARS-CoV-2). This disease was named as "Coronavirus Disease 2019" (COVID-19). SARS-CoV-2 was first identified as an etiological pathogen of COVID-19, belonging to the species of severe acute respiratory syndrome-related coronaviruses (SARSr-CoV). The speed of both the geographical transmission and the sudden increase in numbers of cases is much faster than SARS and Middle East respiratory syndrome (MERS). COVID-19 is the first global pandemic caused by a coronavirus, which outbreaks in 211 countries/territories/areas. The vaccine against COVID-19, regarded as an effective prophylactic strategy for control and prevention, is being developed in about 90 institutions worldwide. The experiences and lessons encountered in the previous SARS and MERS vaccine research can be used for reference in the development of COVID-19 vaccine. The present paper hopes to provide some insights for COVID-19 vaccines researchers.

negative: CD8 memory T cells: cross-reactivity and heterologous immunity Abstract Virus-specific memory T cell populations demonstrate plasticity in antigen recognition and in their ability to accommodate new memory T cell populations. The degeneracy of T cell antigen recognition and the flexibility of diverse antigen-specific repertoires allow the host to respond to a multitude of pathogens while accommodating these numerous large memory pools in a finite immune system. These cross-reactive memory T cells can be employed in immune responses and mediate protective immunity, but they can also induce life-threatening immunopathology or impede transplantation tolerance and graft survival. Here we discuss examples of altered viral pathogenesis occurring as a consequence of heterologous T cell immunity and propose models for the maintenance of a dynamic pool of memory cells.

negative: A Human PrM Antibody That Recognizes a Novel Cryptic Epitope on Dengue E Glycoprotein Dengue virus (DENV) is a major mosquito-borne pathogen infecting up to 100 million people each year; so far no effective treatment or vaccines are available. Recently, highly cross-reactive and infection-enhancing pre-membrane (prM)-specific antibodies were found to dominate the anti-DENV immune response in humans, raising concern over vaccine candidates that contain native dengue prM sequences. In this study, we have isolated a broadly cross-reactive prM-specific antibody, D29, during a screen with a non-immunized human Fab-phage library against the four serotypes of DENV. The antibody is capable of restoring the infectivity of virtually non-infectious immature DENV (imDENV) in FcγR-bearing K562 cells. Remarkably, D29 also cross-reacted with a cryptic epitope on the envelope (E) protein located to the DI/DII junction as evidenced by site-directed mutagenesis. This cryptic epitope, while inaccessible to antibody binding in a native virus particle, may become exposed if E is not properly folded. These findings suggest that generation of anti-prM antibodies that enhance DENV infection may not be completely avoided even with immunization strategies employing E protein alone or subunits of E proteins.

negative: Evidence for the existence of two forms of α(2A)-adrenoceptors in the rat The α(2A)-adrenoceptors in rat spleen, kidney, spinal cord and cerebral cortex were studied using [(3)H]-RX821002 radioligand binding. In the spleen, spinal cord and cerebral cortex, the ligand bound to saturable sites with a K (d) of about 1 nmol/l and capacities of 134, 240 and 290 fmol/mg protein, respectively. Computer modelling competition curves for 39 drugs, including those for α(2A)-, α(2B)- or α(2C)-adrenoceptor selective drugs, indicated that the sites labelled by [(3)H]-RX821002 in the spleen consisted of a single population of α(2A)-adrenoceptors. However, the competition curves for guanoxabenz were definitely biphasic and resolved into two site fits, indicating that guanoxabenz was binding to both high affinity (K (d) = 35 nmol/1) and low affinity (K (d) = 8900 nmol/1) α(2A)-adrenoceptor sites in the proportions 57% and 43%, respectively. The K (d) (S)for a number of α(2)-adrenoceptor subtype selective drugs, measured in competition with [(3)H]-RX821002 in cerebral cortex and spinal cord, were highly correlated with those obtained in the spleen indicating their α(2A)-adrenoceptor nature. However, by contrast to the results with the spleen, the guanoxabenz competition curves for the spinal cord and cerebral cortex were monophasic and resolved only into one site fits, the K (d) of guanoxabenz being about 4000 nmol/l for both tissues. Drug K (d) (S)for kidney α(2A)-adrenoceptors were also determined using [(3)H]-RX821002. For nearly all drugs tested, the K (d) (S)were highly correlated with those found for the α(2A)-adrenoceptors in the other rat tissues. However, for guanoxabenz, the data indicated that it competed with [(3)H]-RX821002 at a single α(2A)-adrenoceptor site with a K (d) of 39 nmol/1. When the rat α(2A)-adrenoceptor gene RG20 was transiently expressed in COS-7 cells and its ligand binding properties probed using [(3)H]-RX821002, the drug K (d) (S)obtained were also highly correlated with those found for the α(2A)-adrenoceptors in the spleen, cerebral cortex, spinal cord and kidney of the rat. For the RG20 encoded receptor, the guanoxabenz competition curves were steep and monophasic and modelled best into one site fits, with the Kd of guanoxabenz being 5200 nmol/1. It is suggested that guanoxabenz can differentiate between two forms of α(2A)-adrenoceptors in the rat: α(2A1) and α(2A2). The α(2A1)-form is present in the spleen and kidney where it shows a high apparent affinity for guanoxabenz. The α(2A2)-form shows a low apparent affinity for guanoxabenz and is present in the spleen, cerebal cortex and spinal cord. The α(2A2)-form of the rat α(2)-adrenoceptor appears to be encoded by the RG20 gene. The α(2A), and α(2A2)-adrenoceptor forms do not represent high and low affinity receptor forms for agonists because assays included EDTA, Gpp(NH)p and Na(+), which eliminated the high affinity receptors for agonists.

negative: Novel Coronavirus Disease (COVID-19) The present outbreak of the novel coronavirus initially called as “2019 novel coronavirus” or “2019-nCoV” by the World Health Organization (WHO), is also known as “Wuhan coronavirus” or “Wuhan pneumonia”, as it started in the Wuhan city of China in early December of 2019. This new coronavirus-associated acute respiratory deadly disease is now officially named as Corona Virus Disease-19 (COVID-19) by the WHO. From China, this epidemic has now spread to all over the world. On 11 March 2020, the WHO recognised COVID-19 as a pandemic. A pandemic refers to a disease that has spread to several countries, continents, if not worldwide. While the information available on this newly identified virus is limited and evolving, here is a quick run-down of what has been figured out so far.

negative: TANK-Binding Kinase 1-Dependent Responses in Health and Autoimmunity The pathogenesis of autoimmune diseases, such as rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) is driven by genetic predisposition and environmental triggers that lead to dysregulated immune responses. These include the generation of pathogenic autoantibodies and aberrant production of inflammatory cytokines. Current therapies for RA and other autoimmune diseases reduce inflammation by targeting inflammatory mediators, most of which are innate response cytokines, resulting in generalized immunosuppression. Overall, this strategy has been very successful, but not all patients respond, responses can diminish over time and numerous side effects can occur. Therapies that target the germinal center (GC) reaction and/or antibody-secreting plasma cells (PC) potentially provide a novel approach. TANK-binding kinase 1 (TBK1) is an IKK-related serine/threonine kinase best characterized for its involvement in innate antiviral responses through the induction of type I interferons. TBK1 is also gaining attention for its roles in humoral immune responses. In this review, we discuss the role of TBK1 in immunological pathways involved in the development and maintenance of antibody responses, with particular emphasis on its potential relevance in the pathogenesis of humoral autoimmunity. First, we review the role of TBK1 in the induction of type I IFNs. Second, we highlight how TBK1 mediates inducible T cell co-stimulator signaling to the GC T follicular B helper population. Third, we discuss emerging evidence on the contribution of TBK1 to autophagic pathways and the potential implications for immune cell function. Finally, we discuss the therapeutic potential of TBK1 inhibition in autoimmunity.

negative: Computational simulations reveal the binding dynamics between human ACE2 and the receptor binding domain of SARS-CoV-2 spike protein A novel coronavirus (the SARS-CoV-2) has been identified in January 2020 as the causal pathogen for COVID-19 pneumonia, an outbreak started near the end of 2019 in Wuhan, China. The SARS-CoV-2 was found to be closely related to the SARS-CoV, based on the genomic analysis. The Angiotensin converting enzyme 2 protein (ACE2) utilized by the SARS-CoV as a receptor was found to facilitate the infection of SARS-CoV-2 as well, initiated by the binding of the spike protein to the human ACE2. Using homology modeling and molecular dynamics (MD) simulation methods, we report here the detailed structure of the ACE2 in complex with the receptor binding domain (RBD) of the SARS-CoV-2 spike protein. The predicted model is highly consistent with the experimentally determined complex structures. Plausible binding modes between human ACE2 and the RBD were revealed from all-atom MD simulations. The simulation data further revealed critical residues at the complex interface and provided more details about the interactions between the SARS-CoV-2 RBD and human ACE2. Two mutants mimicking rat ACE2 were modeled to study the mutation effects on RBD binding to ACE2. The simulations showed that the N-terminal helix and the K353 of the human ACE2 alter the binding modes of the CoV2-RBD to the ACE2.

negative: Rapid and accurate identification of COVID-19 infection through machine learning based on clinical available blood test results Since the sudden outbreak of coronavirus disease 2019 (COVID-19), it has rapidly evolved into a momentous global health concern. Due to the lack of constructive information on the pathogenesis of COVID-19 and specific treatment, it highlights the importance of early diagnosis and timely treatment. In this study, 11 key blood indices were extracted through random forest algorithm to build the final assistant discrimination tool from 49 clinical available blood test data which were derived by commercial blood test equipments. The method presented robust outcome to accurately identify COVID-19 from a variety of suspected patients with similar CT information or similar symptoms, with accuracy of 0.9795 and 0.9697 for the cross-validation set and test set, respectively. The tool also demonstrated its outstanding performance on an external validation set that was completely independent of the modeling process, with sensitivity, specificity, and overall accuracy of 0.9512, 0.9697, and 0.9595, respectively. Besides, 24 samples from overseas infected patients with COVID-19 were used to make an in-depth clinical assessment with accuracy of 0.9167. After multiple verification, the reliability and repeatability of the tool has been fully evaluated, and it has the potential to develop into an emerging technology to identify COVID-19 and lower the burden of global public health. The proposed tool is well-suited to carry out preliminary assessment of suspected patients and help them to get timely treatment and quarantine suggestion. The assistant tool is now available online at http://lishuyan.lzu.edu.cn/COVID2019_2/.

negative: COVID-19 Infection: Implications for Perioperative and Critical Care Physicians Healthcare systems worldwide are responding to Coronavirus Disease 2019 (COVID-19), an emerging infectious syndrome caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) virus. Patients with COVID-19 can progress from asymptomatic or mild illness to hypoxemic respiratory failure or multisystem organ failure, necessitating intubation and intensive care management. Healthcare providers, and particularly anesthesiologists, are at the frontline of this epidemic, and they need to be aware of the best available evidence to guide therapeutic management of patients with COVID-19 and to keep themselves safe while doing so. Here, the authors review COVID-19 pathogenesis, presentation, diagnosis, and potential therapeutics, with a focus on management of COVID-19–associated respiratory failure. The authors draw on literature from other viral epidemics, treatment of acute respiratory distress syndrome, and recent publications on COVID-19, as well as guidelines from major health organizations. This review provides a comprehensive summary of the evidence currently available to guide management of critically ill patients with COVID-19.

negative: Disposable N95 Masks Pass Qualitative Fit-Test But Have Decreased Filtration Efficiency after Cobalt-60 Gamma Irradiation The current COVID-19 pandemic has led to a dramatic shortage of masks and other personal protective equipment (PPE) in hospitals around the globe. One component of PPE that is in particular demand are disposable N95 face masks. To alleviate this, many methods of N95 mask sterilization have been studied and proposed with the hope of being able to safely reuse masks. Two major considerations must be made when re-sterilizing masks: (1) the sterilization method effectively kills pathogens, penetrating into the fibers of the mask, and (2) the method does not degrade the operational integrity of the N95 filters. We studied Cobalt-60 gamma irradiation as a method of effective sterilization without inducing mask degradation. Significant literature exists supporting the use of gamma radiation as a sterilization method, with viral inactivation of SARS-CoV reported at doses of at most 10 kGy, with other studies supporting 5 kGy for many types of viruses. However, concerns have been raised about the radiation damaging the fiber material within the mask, specifically by causing cross-linking of polymers, leading to cracking and degradation during fitting and/or deployment. A set of 3M 8210 and 9105 masks were irradiated using MIT's Co-60 irradiator. Three masks of each type received 0 kiloGray (kGy), 10 kGy and 50 kGy of approximately 1.3 MeV gamma radiation from the circular cobalt sources, at a dose rate of 2.2 kGy per hour. Following this sterilization procedure, the irradiated masks passed a OSHA Gerson Qualitative Fit Test QLFT 50 (saccharin apparatus) when donned correctly, performed at the Brigham and Women's Hospital, in a blinded study repeated in triplicate. However, the masks' filtration of 0.3 um particles was significantly degraded, even at 10 kGy. These results suggest against gamma, and possibly all ionizing radiation, as a method of disposable N95 sterilization. Even more importantly, they argue against using the qualitative fit test alone to assess mask integrity.

negative: Gut microbiota and Covid-19- possible link and implications. Covid-19 is a major pandemic facing the world today caused by SARS-CoV-2 which has implications on our understanding of infectious diseases. Although, SARS-Cov-2 primarily causes lung infection through binding of ACE2 receptors present on the alveolar epithelial cells, yet it was recently reported that SARS-CoV-2 RNA was found in the faeces of infected patients. Interestingly, the intestinal epithelial cells particularly the enterocytes of the small intestine also express ACE2 receptors. Role of the gut microbiota in influencing lung diseases has been well articulated. It is also known that respiratory virus infection causes perturbations in the gut microbiota. Diet, environmental factors and genetics play an important role in shaping gut microbiota which can influence immunity. Gut microbiota diversity is decreased in old age and Covid-19 has been mainly fatal in elderly patients which again points to the role the gut microbiota may play in this disease. Improving gut microbiota profile by personalized nutrition and supplementation known to improve immunity can be one of the prophylactic ways by which the impact of this disease can be minimized in old people and immune-compromised patients. More trials may be initiated to see the effect of co-supplementation of personalized functional food including prebiotics/probiotics along with current therapies.

negative: Current Status of the COVID-19 Outbreak and Emerging Management through Pharmaceutical Therapeutic Strategy. The latest SARS COV2 coronavirus contributes to a pandemic of millions of COVID-19. Because there is no defensive immunity in humans and a virus can overcome inborn immune reaction, it can propagate unhindered, mostly in tissues contaminated. No unique therapies for COVID-19 contaminated patients are available at this time. The insights learned from previous respiratory viral infection control have given guidance into COVID-19 therapy. Several complementary treatments have been tentatively introduced in hospital environments such as immune-modulators, antiviral, convalescent plasma transfusions and natural products. In COVID-19 patients, some of these therapies have provided substantial curative benefits. Moreover, numerous studies and clinical trials are being carried out in order to determine the efficacy of current pharmaceutical and natural products and establish possible therapeutic strategies for producing novel COVID-19 medicines. We summarized and defined the modes of mechanism, protection and efficacy on existing therapeutic strategies for diseases linked to COVID-19 infection.

negative: FIV vaccine development and its importance to veterinary and human medicine: a review FIV vaccine 2002 update and review Abstract Feline immunodeficiency virus (FIV) is a natural infection of domestic cats that results in acquired immunodeficiency syndrome resembling human immunodeficiency virus (HIV) infection in humans. The worldwide prevalence of FIV infection in domestic cats has been reported to range from 1 to 28%. Hence, an effective FIV vaccine will have an important impact on veterinary medicine in addition to being used as a small animal AIDS model for humans. Since the discovery of FIV reported in 1987, FIV vaccine research has pursued both molecular and conventional vaccine approaches toward the development of a commercial product. Published FIV vaccine trial results from 1998 to the present have been compiled to update the veterinary clinical and research communities on the immunologic and experimental efficacy status of these vaccines. A brief report is included on the outcome of the 10 years of collaborative work between industry and academia which led to recent USDA approval of the first animal lentivirus vaccine, the dual-subtype FIV vaccine. The immunogenicity and efficacy of the experimental prototype, dual-subtype FIV vaccine and the efficacy of the currently approved commercial, dual-subtype FIV vaccine (Fel-O-Vax FIV) are discussed. Potential cross-reactivity complications between commercial FIV diagnostic tests, Idexx Snap Combo Test® and Western blot assays, and sera from previously vaccinated cats are also discussed. Finally, recommendations are made for unbiased critical testing of new FIV vaccines, the currently USDA approved vaccine, and future vaccines in development.

negative: Immunogenicity of SARS inactivated vaccine in BALB/c mice Abstract Severe acute respiratory syndrome (SARS) is a serious infectious threat to public health. To create a novel trial vaccine and evaluate its potency, we attempted to generate a SARS inactivated vaccine using SARS coronavirus (SARS-CoV) strain F69 treated with formaldehyde and mixed with Al(OH)3. Three doses of the vaccine were used to challenge three groups of BALB/c mice. We found that the mice exhibited specific IgM on day 4 and IgG on day 8. The peak titers of IgG were at day 47 in low-dose group (1:19,200) and high-dose group (1:38,400) whereas in middle-dose group (1:19,200), the peak was at day 40. On day 63, the IgG levels reached a plateau. Neutralization assay demonstrated that the antisera could protect Vero-E6 cells from SARS-CoV's infection. Analysis of the antibody specificity revealed that the mouse antisera contained a mixture of antibodies specifically against the structure proteins of SARS-CoV. Furthermore, the mouse antisera conferred higher amount of antibodies against protein N, polypeptide S4 and S2 than those of proteins M and 3CL. These findings suggest that the inactivated SARS-CoV could preserve its antigenicity and the inactivated vaccine can stimulate mice to produce high levels of antibodies with neutralization activity. Results also suggest that polypeptides originating from protein N or S might be a potential target for the generation of a recombinant SARS vaccine.

negative: Efficacy of Intranasal Administration of a Modified Live Feline Herpesvirus 1 and Feline Calicivirus Vaccine against Disease Caused by Bordetella bronchiseptica after Experimental Challenge BACKGROUND: Studies suggest that intranasal vaccination can stimulate nonspecific immunity against agents not contained within the vaccine, but this effect is not reported for cats. HYPOTHESIS: A modified live feline herpesvirus‐1 (FHV‐1) and feline calicivirus (FCV) intranasal vaccine will reduce clinical signs of disease caused by experimental infection with Bordetella bronchiseptica. ANIMALS: Twenty specific pathogen‐free 12‐week‐old kittens. METHODS: Experimental study. Cats were randomized into 2 groups of 10 cats each. The vaccinated group was administered a single intranasal dose of a commercially available vaccine containing modified live strains of FHV‐1 and FCV, and the control group remained unvaccinated. All 20 cats were administered B. bronchiseptica by nasal inoculation 7 days later and were observed daily for clinical signs of illness for 20 days. RESULTS: In the first 10 days after B. bronchiseptica challenge, vaccinated cats were less likely to be clinically ill than control cats with a median clinical score of 0/180 (range 0–5) versus 2/180 (range 0–8) (P = .01). Nine of 10 control cats and 2 of 10 vaccinated cats were recorded as sneezing during days 1–10 after challenge (P = .006). CONCLUSIONS AND CLINICAL IMPORTANCE: Intranasal vaccination against FHV‐1 and FCV decreased signs of illness due to an infectious agent not contained in the vaccine. This nonspecific immunity could be beneficial for protection against organisms for which vaccines are not available and as protection before development of vaccine‐induced humoral immunity.

negative: Severe Acute Respiratory Syndrome: Developing a Research Response When severe acute respiratory syndrome (SARS) first came to world attention in March 2003, it was immediately perceived to be a global threat with a pandemic potential. To help coordinate international research efforts, the National Institute of Allergy and Infectious Diseases convened a colloquium entitled SARS: Developing a Research Response on 30 May 2003. Breakout sessions intended to identify unmet research needs in 5 areas of SARS research—clinical research, epidemiology, diagnostics, therapeutics, and vaccines—are summarized here. Since this meeting, however, the identified research needs have been only partially met. Needs that have yet to be realized include reliable methods for early identification of individuals with SARS, a full description of SARS pathogenesis and immune response, and animal models that faithfully mimic SARS respiratory symptoms. It is also of the utmost importance that the global scientific community enhance mechanisms for international cooperation and planning for SARS research, as well as for other emerging infectious disease threats that are certain to arise in the future.

negative: Chapter Eight Molecular Basis of Coronavirus Virulence and Vaccine Development Abstract Virus vaccines have to be immunogenic, sufficiently stable, safe, and suitable to induce long-lasting immunity. To meet these requirements, vaccine studies need to provide a comprehensive understanding of (i) the protective roles of antiviral B and T-cell-mediated immune responses, (ii) the complexity and plasticity of major viral antigens, and (iii) virus molecular biology and pathogenesis. There are many types of vaccines including subunit vaccines, whole-inactivated virus, vectored, and live-attenuated virus vaccines, each of which featuring specific advantages and limitations. While nonliving virus vaccines have clear advantages in being safe and stable, they may cause side effects and be less efficacious compared to live-attenuated virus vaccines. In most cases, the latter induce long-lasting immunity but they may require special safety measures to prevent reversion to highly virulent viruses following vaccination. The chapter summarizes the recent progress in the development of coronavirus (CoV) vaccines, focusing on two zoonotic CoVs, the severe acute respiratory syndrome CoV (SARS-CoV), and the Middle East respiratory syndrome CoV, both of which cause deadly disease and epidemics in humans. The development of attenuated virus vaccines to combat infections caused by highly pathogenic CoVs was largely based on the identification and characterization of viral virulence proteins that, for example, interfere with the innate and adaptive immune response or are involved in interactions with specific cell types, such as macrophages, dendritic and epithelial cells, and T lymphocytes, thereby modulating antiviral host responses and viral pathogenesis and potentially resulting in deleterious side effects following vaccination.

negative: COVID-19: room for treating T cell exhaustion?

negative: COVID-19 pneumonia manifestations at the admission on chest ultrasound, radiographs, and CT: single-center study and comprehensive radiologic literature review PURPOSE: To investigate the imaging features of emerging COVID-19 pneumonia on chest ultrasound (US), radiographs (CXR) and computed tomography (CT) examinations performed at admission and to provide a comprehensive radiological literature review on ongoing radiological data from recent publications. MATERIALS AND METHODS: In this retrospective single-center study, we enrolled consecutive patients from February 15, 2020, to March 15, 2020, with laboratory-confirmed SARS-CoV-2 hospitalized in Valduce Hospital (Como, Italy). Multi-modality imaging findings were evaluated and compared. Literature research was conducted through a methodical search on Pubmed and Embase databases. RESULTS: Fifty-eight patients (36 men, 22 women; age range, 18–98 years) were included in the study. Among these, chest US, CXR, and CT were performed respectively in twenty-two, thirty-two and forty-two patients. Lung US findings were consistent with diffuse B lines (100%) and subpleural consolidations (27.3%). CXR showed prevalent manifestations of consolidations (46.9%) and hazy increased opacities (37.5%). Typical CT features included bilateral and multilobar ground-glass opacities (GGO) with (59.5%) and without (35.7%) consolidations having a predominantly peripheral distribution (64.3%). Other imaging features included crazy paving pattern (57.1%), fibrous stripes (50%), subpleural lines (35.7%), architectural distortion (28.6%), air bronchogram sign (26.2%), vascular thickening (23.8%) and nodules (2.4%). Also, enlarged lymph nodes (14.3 %) and pleural effusion (7.1%) were observed. The literature review identified twenty-six original studies supporting our imaging chest findings. CONCLUSION: The spectrum of chest imaging manifestations of COVID-19 pneumonia upon admission includes B-lines and consolidations on US, consolidations and hazy increased opacities on CXR, and multifocal GGO with consolidations on CT.

negative: Guidelines for preventing respiratory illness in older adults aged 60 years and above living in long-term care: A rapid review of clinical practice guidelines Background: The overall objective of this rapid review was to identify infection protection and control recommendations from published clinical practice guidelines (CPGs) for adults aged 60 years and older in long-term care settings Methods: Comprehensive searches in MEDLINE, EMBASE, the Cochrane Library, and relevant CPG publishers/repositories were carried out in early March 2020. Title/abstract and full-text screening, data abstraction, and quality appraisal (AGREE-II) were carried out by single reviewers. Results: A total of 17 relevant CPGs were identified, published in the USA (n=8), Canada (n=6), Australia (n=2), and the United Kingdom (n=1). All of the CPGs dealt with infection control in long-term care facilities (LTCF) and addressed various types of viral respiratory infections (e.g., influenza, COVID-19, severe acute respiratory syndrome). Ten or more CPGs recommended the following infection control measures in LTCF: hand hygiene (n=13), wearing personal protective equipment (n=13), social distancing or isolation (n=13), disinfecting surfaces (n=12), droplet precautions (n=12), surveillance and evaluation (n=11), and using diagnostic testing to confirm illness (n=10). While only two or more CPGs recommended these infection control measures: policies and procedures for visitors, staff and/or residents (n=9), respiratory hygiene/cough etiquette (n=9), providing supplies (n=9), staff and/or residents education (n=8), increasing communication (n=6), consulting or notifying health professionals (n=6), appropriate ventilation practices (n=2), and cohorting equipment (n=2). Ten CPGs also addressed management of viral respiratory infections in LTCF and recommended antiviral chemoprophylaxis (n=10) and one CPG recommended early mobilization of residents. Conclusion: The recommendations from current guidelines overall seem to support environmental measures for infection prevention and antiviral chemoprophylaxis for infection management as the most appropriate first-line response to viral respiratory illness in long-term care.

negative: Coronavirus Disease 2019: Coronaviruses and Blood Safety Abstract With the outbreak of unknown pneumonia in Wuhan, China, in December 2019, a new coronavirus, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), aroused the attention of the entire world. The current outbreak of infections with SARS-CoV-2 is termed Coronavirus Disease 2019 (COVID-19). The World Health Organization declared COVID-19 in China as a Public Health Emergency of International Concern. Two other coronavirus infections—SARS in 2002-2003 and Middle East Respiratory Syndrome (MERS) in 2012—both caused severe respiratory syndrome in humans. All 3 of these emerging infectious diseases leading to a global spread are caused by β-coronaviruses. Although coronaviruses usually infect the upper or lower respiratory tract, viral shedding in plasma or serum is common. Therefore, there is still a theoretical risk of transmission of coronaviruses through the transfusion of labile blood products. Because more and more asymptomatic infections are being found among COVID-19 cases, considerations of blood safety and coronaviruses have arisen especially in endemic areas. In this review, we detail current evidence and understanding of the transmission of SARS-CoV, MERS–CoV, and SARS-CoV-2 through blood products as of February 10, 2020, and also discuss pathogen inactivation methods on coronaviruses.

negative: Global Infections—Avian Influenza and Other Significant Emerging Pathogens: An Overview

negative: Composition and divergence of coronavirus spike proteins and host ACE2 receptors predict potential intermediate hosts of SARS-CoV-2 From the beginning of 2002 and 2012, severe respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV) crossed the species barriers to infect humans, causing thousands of infections and hundreds of deaths, respectively. Currently, a novel coronavirus (SARS-CoV-2), which has become the cause of the outbreak of Coronavirus Disease 2019 (COVID-19), was discovered. Until 18 February 2020, there were 72 533 confirmed COVID-19 cases (including 10 644 severe cases) and 1872 deaths in China. SARS-CoV-2 is spreading among the public and causing substantial burden due to its human-to-human transmission. However, the intermediate host of SARS-CoV-2 is still unclear. Finding the possible intermediate host of SARS-CoV-2 is imperative to prevent further spread of the epidemic. In this study, we used systematic comparison and analysis to predict the interaction between the receptor-binding domain (RBD) of coronavirus spike protein and the host receptor, angiotensin-converting enzyme 2 (ACE2). The interaction between the key amino acids of S protein RBD and ACE2 indicated that, other than pangolins and snakes, as previously suggested, turtles (Chrysemys picta bellii, Chelonia mydas, and Pelodiscus sinensis) may act as the potential intermediate hosts transmitting SARS-CoV-2 to humans.

negative: Prevalence of Underlying Diseases in Hospitalized Patients with COVID-19: a Systematic Review and Meta-Analysis INTRODUCTION: In the beginning of 2020, an unexpected outbreak due to a new corona virus made the headlines all over the world. Exponential growth in the number of those affected makes this virus such a threat. The current meta-analysis aimed to estimate the prevalence of underlying disorders in hospitalized COVID-19 patients. METHODS: A comprehensive systematic search was performed on PubMed, Scopus, Web of science, and Google scholar, to find articles published until 15 February 2020. All relevant articles that reported clinical characteristics and epidemiological information of hospitalized COVID-19 patients were included in the analysis. RESULTS: The data of 76993 patients presented in 10 articles were included in this study. According to the meta-analysis, the pooled prevalence of hypertension, cardiovascular disease, smoking history and diabetes in people infected with SARS-CoV-2 were estimated as 16.37% (95%CI: 10.15%-23.65%), 12.11% (95%CI 4.40%-22.75%), 7.63% (95%CI 3.83%-12.43%) and 7.87% (95%CI 6.57%-9.28%), respectively. CONCLUSION: According to the findings of the present study, hypertension, cardiovascular diseases, diabetes mellitus, smoking, chronic obstructive pulmonary disease (COPD), malignancy, and chronic kidney disease were among the most prevalent underlying diseases among hospitalized COVID-19 patients, respectively.

negative: [The epidemiological characteristics of an outbreak of 2019 novel coronavirus diseases (COVID-19) in China]. Objective: An outbreak of 2019 novel coronavirus diseases (COVID-19) in Wuhan, China has spread quickly nationwide. Here, we report results of a descriptive, exploratory analysis of all cases diagnosed as of February 11, 2020. Methods: All COVID-19 cases reported through February 11, 2020 were extracted from China's Infectious Disease Information System. Analyses included: 1) summary of patient characteristics; 2) examination of age distributions and sex ratios; 3) calculation of case fatality and mortality rates; 4) geo-temporal analysis of viral spread; 5) epidemiological curve construction; and 6) subgroup analysis. Results: A total of 72 314 patient records-44 672 (61.8%) confirmed cases, 16 186 (22.4%) suspected cases, 10567 (14.6%) clinical diagnosed cases (Hubei only), and 889 asymptomatic cases (1.2%)-contributed data for the analysis. Among confirmed cases, most were aged 30-79 years (86.6%), diagnosed in Hubei (74.7%), and considered mild (80.9%). A total of 1 023 deaths occurred among confirmed cases for an overall case-fatality rate of 2.3%. The COVID-19 spread outward from Hubei sometime after December 2019 and by February 11, 2020, 1 386 counties across all 31 provinces were affected. The epidemic curve of onset of symptoms peaked in January 23-26, then began to decline leading up to February 11. A total of 1 716 health workers have become infected and 5 have died (0.3%). Conclusions: The COVID-19 epidemic has spread very quickly. It only took 30 days to expand from Hubei to the rest of Mainland China. With many people returning from a long holiday, China needs to prepare for the possible rebound of the epidemic.

negative: Lack of Innate Interferon Responses during SARS Coronavirus Infection in a Vaccination and Reinfection Ferret Model In terms of its highly pathogenic nature, there remains a significant need to further define the immune pathology of SARS-coronavirus (SARS-CoV) infection, as well as identify correlates of immunity to help develop vaccines for severe coronaviral infections. Here we use a SARS-CoV infection-reinfection ferret model and a functional genomics approach to gain insight into SARS immunopathogenesis and to identify correlates of immune protection during SARS-CoV-challenge in ferrets previously infected with SARS-CoV or immunized with a SARS virus vaccine. We identified gene expression signatures in the lungs of ferrets associated with primary immune responses to SARS-CoV infection and in ferrets that received an identical second inoculum. Acute SARS-CoV infection prompted coordinated innate immune responses that were dominated by antiviral IFN response gene (IRG) expression. Reinfected ferrets, however, lacked the integrated expression of IRGs that was prevalent during acute infection. The expression of specific IRGs was also absent upon challenge in ferrets immunized with an inactivated, Al(OH)(3)-adjuvanted whole virus SARS vaccine candidate that protected them against SARS-CoV infection in the lungs. Lack of IFN-mediated immune enhancement in infected ferrets that were previously inoculated with, or vaccinated against, SARS-CoV revealed 9 IRG correlates of protective immunity. This data provides insight into the molecular pathogenesis of SARS-CoV and SARS-like-CoV infections and is an important resource for the development of CoV antiviral therapeutics and vaccines.

negative: Can we contain the COVID-19 outbreak with the same measures as for SARS? Summary The severe acute respiratory syndrome (SARS) outbreak in 2003 resulted in more than 8000 cases and 800 deaths. SARS was eventually contained by means of syndromic surveillance, prompt isolation of patients, strict enforcement of quarantine of all contacts, and in some areas top-down enforcement of community quarantine. By interrupting all human-to-human transmission, SARS was effectively eradicated. By contrast, by Feb 28, 2020, within a matter of 2 months since the beginning of the outbreak of coronavirus disease 2019 (COVID-19), more than 82 000 confirmed cases of COVID-19 have been reported with more than 2800 deaths. Although there are striking similarities between SARS and COVID-19, the differences in the virus characteristics will ultimately determine whether the same measures for SARS will also be successful for COVID-19. COVID-19 differs from SARS in terms of infectious period, transmissibility, clinical severity, and extent of community spread. Even if traditional public health measures are not able to fully contain the outbreak of COVID-19, they will still be effective in reducing peak incidence and global deaths. Exportations to other countries need not result in rapid large-scale outbreaks, if countries have the political will to rapidly implement countermeasures.

negative: Role of toll-like receptors in respiratory diseases There has been growing interest in the last 10 years in the study of innate immunity, in particular because of the possible role that toll-like receptors (TLR) may play in the pathogenesis of some respiratory diseases including, asthma, chronic obstructive pulmonary disease, and infections. TLR are a family of type 1 transmembrane proteins, responsible for recognising molecular patterns associated with pathogens (PAMP, pathogen-associated molecular patterns), and expressed by a broad spectrum of infectious agents. This recognition leads to a quick production of cytokines and chemokines which provides a long-lasting adaptive response to the pathogen. At present, it is considered //It is currently considered that the administration of drugs which modulate the activity of these receptors upwards or downwards may represent major therapeutic progress for handling these diseases. The aim of this review is to describe the different TLS, define their possible role in the pathogenesis of the main respiratory diseases and finally, speculate over the therapeutic possibilities which their modulation, agonist or antagonist, offers as possible therapeutic targets.

negative: Transmission routes of 2019-nCoV and controls in dental practice A novel β-coronavirus (2019-nCoV) caused severe and even fetal pneumonia explored in a seafood market of Wuhan city, Hubei province, China, and rapidly spread to other provinces of China and other countries. The 2019-nCoV was different from SARS-CoV, but shared the same host receptor the human angiotensin-converting enzyme 2 (ACE2). The natural host of 2019-nCoV may be the bat Rhinolophus affinis as 2019-nCoV showed 96.2% of whole-genome identity to BatCoV RaTG13. The person-to-person transmission routes of 2019-nCoV included direct transmission, such as cough, sneeze, droplet inhalation transmission, and contact transmission, such as the contact with oral, nasal, and eye mucous membranes. 2019-nCoV can also be transmitted through the saliva, and the fetal–oral routes may also be a potential person-to-person transmission route. The participants in dental practice expose to tremendous risk of 2019-nCoV infection due to the face-to-face communication and the exposure to saliva, blood, and other body fluids, and the handling of sharp instruments. Dental professionals play great roles in preventing the transmission of 2019-nCoV. Here we recommend the infection control measures during dental practice to block the person-to-person transmission routes in dental clinics and hospitals.

negative: Infect volunteers to speed a coronavirus vaccine?

negative: Role of changes in SARS-CoV-2 spike protein in the interaction with the human ACE2 receptor: An in silico analysis Many human viral diseases are a consequence of a zoonotic event. Some of the diseases caused by these zoonotic events have affected millions of people around the world, some of which have resulted in high rates of morbidity/mortality in humans. Changes in the viral proteins that function as ligands of the host receptor may promote the spillover between species. The most recent of these zoonotic events that have caused an ongoing epidemic of high magnitude is the Covid-19 epidemics caused by SARS-CoV-2. The aim of this study was to determine the mutation(s) in the sequence of the spike protein of the SARS-CoV-2 that might be favoring human to human transmission. An in silico approach was performed, and changes were detected in the S1 subunit of the receptor-binding domain of spike. The observed changes have significant effect on SARS-CoV-2 spike/ACE2 interaction and produce a reduction in the binding energy, compared to the one of the Bat-CoV to this receptor. The data presented in this study suggest a higher affinity of the SARS-Cov-2 spike protein to the human ACE2 receptor, compared to the one of Bat-CoV spike and ACE2. This could be the cause of the rapid viral spread of SARS-CoV-2 in humans.

negative: Glucose-6-Phosphate Dehydrogenase Enhances Antiviral Response through Downregulation of NADPH Sensor HSCARG and Upregulation of NF-κB Signaling Glucose-6-phosphate dehydrogenase (G6PD)-deficient cells are highly susceptible to viral infection. This study examined the mechanism underlying this phenomenon by measuring the expression of antiviral genes—tumor necrosis factor alpha (TNF-α) and GTPase myxovirus resistance 1 (MX1)—in G6PD-knockdown cells upon human coronavirus 229E (HCoV-229E) and enterovirus 71 (EV71) infection. Molecular analysis revealed that the promoter activities of TNF-α and MX1 were downregulated in G6PD-knockdown cells, and that the IκB degradation and DNA binding activity of NF-κB were decreased. The HSCARG protein, a nicotinamide adenine dinucleotide phosphate (NADPH) sensor and negative regulator of NF-κB, was upregulated in G6PD-knockdown cells with decreased NADPH/NADP(+) ratio. Treatment of G6PD-knockdown cells with siRNA against HSCARG enhanced the DNA binding activity of NF-κB and the expression of TNF-α and MX1, but suppressed the expression of viral genes; however, the overexpression of HSCARG inhibited the antiviral response. Exogenous G6PD or IDH1 expression inhibited the expression of HSCARG, resulting in increased expression of TNF-α and MX1 and reduced viral gene expression upon virus infection. Our findings suggest that the increased susceptibility of the G6PD-knockdown cells to viral infection was due to impaired NF-κB signaling and antiviral response mediated by HSCARG.

negative: COVID-19, an opportunity to reevaluate the correlation between long-term effects of anthropogenic pollutants on viral epidemic/pandemic events and prevalence Occupational, residential, dietary and environmental exposures to mixtures of synthetic anthropogenic chemicals after World War II have a strong relationship with the increase of chronic diseases, health cost and environmental pollution. The link between environment and immunity is particularly intriguing as it is known that chemicals and drugs can cause immunotoxicity (e.g., allergies and autoimmune diseases). In this review, we emphasize the relationship between long-term exposure to xenobiotic mixtures and immune deficiency inherent to chronic diseases and epidemics/pandemics. We also address the immunotoxicologic risk of vulnerable groups, taking into account biochemical and biophysical properties of SARS-CoV-2 and its immunopathological implications. We particularly underline the common mechanisms by which xenobiotics and SARS-CoV-2 act at the cellular and molecular level. We discuss how long-term exposure to thousand chemicals in mixtures, mostly fossil fuel derivatives, exposure toparticle matters, metals, ultraviolet (UV)–B radiation, ionizing radiation and lifestyle contribute to immunodeficiency observed in the contemporary pandemic, such as COVID-19, and thus threaten global public health, human prosperity and achievements, and global economy. Finally, we propose metrics which are needed to address the diverse health effects of anthropogenic COVID-19 crisis at present and those required to prevent similar future pandemics.

negative: Using the spike protein feature to predict infection risk and monitor the evolutionary dynamic of coronavirus BACKGROUND: Coronavirus can cross the species barrier and infect humans with a severe respiratory syndrome. SARS-CoV-2 with potential origin of bat is still circulating in China. In this study, a prediction model is proposed to evaluate the infection risk of non-human-origin coronavirus for early warning. METHODS: The spike protein sequences of 2666 coronaviruses were collected from 2019 Novel Coronavirus Resource (2019nCoVR) Database of China National Genomics Data Center on Jan 29, 2020. A total of 507 human-origin viruses were regarded as positive samples, whereas 2159 non-human-origin viruses were regarded as negative. To capture the key information of the spike protein, three feature encoding algorithms (amino acid composition, AAC; parallel correlation-based pseudo-amino-acid composition, PC-PseAAC and G-gap dipeptide composition, GGAP) were used to train 41 random forest models. The optimal feature with the best performance was identified by the multidimensional scaling method, which was used to explore the pattern of human coronavirus. RESULTS: The 10-fold cross-validation results showed that well performance was achieved with the use of the GGAP (g = 3) feature. The predictive model achieved the maximum ACC of 98.18% coupled with the Matthews correlation coefficient (MCC) of 0.9638. Seven clusters for human coronaviruses (229E, NL63, OC43, HKU1, MERS-CoV, SARS-CoV, and SARS-CoV-2) were found. The cluster for SARS-CoV-2 was very close to that for SARS-CoV, which suggests that both of viruses have the same human receptor (angiotensin converting enzyme II). The big gap in the distance curve suggests that the origin of SARS-CoV-2 is not clear and further surveillance in the field should be made continuously. The smooth distance curve for SARS-CoV suggests that its close relatives still exist in nature and public health is challenged as usual. CONCLUSIONS: The optimal feature (GGAP, g = 3) performed well in terms of predicting infection risk and could be used to explore the evolutionary dynamic in a simple, fast and large-scale manner. The study may be beneficial for the surveillance of the genome mutation of coronavirus in the field.

negative: Partial unlock model for COVID-19 or similar pandemic averts medical and economic disaster Data as of March 29, 2020 show that the flattening strategy for COVID-19 in the U.S. is working so well that a clean removal of social distancing (aka unlock) at any time in 2020 will produce a renewed catastrophe, overloading the healthcare system. Leaving the economy locked down for a long time is its own catastrophe. An SIR-type model with clear parameters suitable for public information, and both tracking and predictive capabilities which learns disease spread characteristics rapidly as policy changes, suggests that a solution to the problem is a partial unlock. Case load can be managed so as not to exceed critical resources such as ventilators, yet allow enough people to get sick that herd immunity develops and a full unlock can be achieved in as little as five weeks from beginning of implementation. The partial unlock could be for example 3 full working days per week. Given that not all areas or individuals will respond, and travel and public gatherings are still unlikely, the partial unlock might be 5 full working days per week. The model can be regionalized easily, and by expediting the resolution of the pandemic in the U.S. medical equipment and volunteers, many of them with already acquired immunity, can be made available to other countries.

negative: Biophysical characterization of the SARS-CoV-2 spike protein binding with the ACE2 receptor and implications for infectivity SARS-CoV-2 is a novel highly virulent pathogen which gains entry to human cells by binding with the cell surface receptor – angiotensin converting enzyme (ACE2). We computationally contrasted the binding interactions between human ACE2 and coronavirus spike protein receptor binding domain (RBD) of the 2002 epidemic-causing SARS-CoV-1, SARS-CoV-2, and bat coronavirus RaTG13 using the Rosetta energy function. We find that the RBD of the spike protein of SARS-CoV-2 is highly optimized to achieve very strong binding with human ACE2 (hACE2) which is consistent with its enhanced infectivity. SARS-CoV-2 forms the most stable complex with hACE2 compared to SARS-CoV-1 (23% less stable) or RaTG13 (11% less stable) while occupying the greatest number of residues in the ATR1 binding site. Notably, the SARS-CoV-2 RBD out-competes the angiotensin 2 receptor type I (ATR1) which is the native binding partner of ACE2 by 35% in terms of the calculated binding affinity. Strong binding is mediated through strong electrostatic attachments with every fourth residue on the N-terminus alpha-helix (starting from Ser19 to Asn53) as the turn of the helix makes these residues solvent accessible. By contrasting the spike protein SARS-CoV-2 Rosetta binding energy with ACE2 of different livestock and pet species we find strongest binding with bat ACE2 followed by human, feline, equine, canine and finally chicken. This is consistent with the hypothesis that bats are the viral origin and reservoir species. These results offer a computational explanation for the increased infectivity of SARS-CoV-2 and allude to therapeutic modalities by identifying and rank-ordering the ACE2 residues involved in binding with the virus.

negative: A Multi-hospital Study in Wuhan, China：Protective Effects of Non-menopause and Female Hormones on SARS-CoV-2 infection Objective To determine the correlation between menstruation status/sex hormones and prognosis of COVID-19, and to identify potential protective factors for female patients. Design, Setting, and Participants A cross-sectional study of COVID-19 patients who were hospitalized at Tongji and Mobile Cabin Hospitals from Jan 28, 2020 to March 8, 2020. Sex differences in severity and composite endpoints (admission to intensive care unit (ICU), use of mechanical ventilation, or death) of COVID-19 patients were compared. The correlation analysis and cox/logistic regression modeling of menstruation status/sex hormones and prognosis were conducted. Correlation between cytokines related to immunity and inflammation and disease severity or estradiol (E2) was revealed.Results Chi square test indicated significant differences in distribution of composite endpoints (p<0.01) and disease severity (p=0.05) between male and female patients (n=1902). 435 female COVID-19 patients with menstruation records were recruited. By the end of Mar 8, 111 patients recovered and discharged (25.3%). Multivariate Cox regression model adjusted for age and severity indicated that post-menopausal patients show the greater risk of hospitalization time than non-menopausal patients (relative hazard [RH], 1.91; 95% confidence interval [CI], 1.06-3.46)Logistic regression model showed that higher AMH as a control for age increases the risk of severity of COVID-19 (HR=0.146, 95%CI= (0.026-0.824) p=0.029). E2 showed protective effect against disease severity (HR=0.335, 95%CI= (0.105-1.070), p=0.046).In the Mann-Whitney U test, the higher levels of IL6 and IL8 were found in severe group (p=0.040, 0.033).The higher levels of IL2R, IL6, IL8 and IL10 were also observed in patients with composite end points(p＜0.001,＜0.001, =0.009, = 0.040).E2 levels were negatively correlated with IL2R, IL6, IL8 and TNFα in luteal phase (Pearson Correlation=-0.592, -0.558, -0.545, -0.623; p=0.033, 0.048, 0.054, 0.023) and with C3 in follicular phase (Pearson Correlation=-0.651; p=0.030). Conclusions and Relevance Menopause is an independent risk factor for COVID-19. E2 and AMH are negatively correlated with COVID-19 severity probably due to their regulation of cytokines related to immunity and inflammation.

negative: Rapid community-driven development of a SARS-CoV-2 tissue simulator The 2019 novel coronavirus, SARS-CoV-2, is an emerging pathogen of critical significance to international public health. Knowledge of the interplay between molecular-scale virus-receptor interactions, single-cell viral replication, intracellular-scale viral transport, and emergent tissue-scale viral propagation is limited. Moreover, little is known about immune system-virus-tissue interactions and how these can result in low-level (asymptomatic) infections in some cases and acute respiratory distress syndrome (ARDS) in others, particularly with respect to presentation in different age groups or pre-existing inflammatory risk factors like diabetes. Given the nonlinear interactions within and among each of these processes, multiscale simulation models can shed light on the emergent dynamics that lead to divergent outcomes, identify actionable “choke points” for pharmacologic interactions, screen potential therapies, and identify potential biomarkers that differentiate patient outcomes. Given the complexity of the problem and the acute need for an actionable model to guide therapy discovery and optimization, we introduce and iteratively refine a prototype of a multiscale model of SARS-CoV-2 dynamics in lung tissue. The first prototype model was built and shared internationally as open source code and an online interactive model in under 12 hours, and community domain expertise is driving rapid refinements with a two-to-four week release cycle. In a sustained community effort, this consortium is integrating data and expertise across virology, immunology, mathematical biology, quantitative systems physiology, cloud and high performance computing, and other domains to accelerate our response to this critical threat to international health.

negative: Focus on Receptors for Coronaviruses with Special Reference to Angiotensin-converting Enzyme 2 as a Potential Drug Target - A Perspective Coronaviruses (CoVs) possess an enveloped, single, positive-stranded RNA genome which encodes for four membrane proteins, namely spike (S), envelope (E), membrane (M) and nucleocapsid (N) proteins 3-5 [1]. With regard to pathogenicity, S proteins are essential for viral entry into host cells [2, 3]. SARS-CoV binds to the angiotensin-converting enzyme (ACE)2 which is present on nonimmune cells, such as respiratory and intestinal epithelial cells, endothelial cells, kidney cells (renal tubules) and cerebral neurons and immune cells, such as alveolar monocytes/macrophages [4-6]. Of note, CD209L or liver/lymph node special intercellular adhesion molecule-3-grabbing non-integrin (SIGN) and dendritic cell (DC)-SIGN are alternative receptors for SARS-CoV but with lower affinity [7]. In the case of MERS-CoV, S proteins bind to the host cell receptor dipeptidyl peptidase 4 (DPP4 or CD26) which is broadly expressed on intestinal, alveolar, renal, hepatic and prostate cells as well as on activated leukocytes [8]. Then, viruses replicate in target cells with release of mature virions, which, in turn, invade new target cells [9]. Evidence has been provided that SARSCoV proteins are cleaved into two subunits, S1 and S2, respectively, and the amino acids 318-510 of the S1 represent the receptor-binding domain (RBD) which binds to ACE2 [10, 11]. Quite importantly, in the context of RBD there is the receptor-binding motif (RBM) (amino acids 424- 494), which accounts for complete binding to ACE2 [11]. Moreover, by means of two residues at positions 479 and 487 RBD allows virus progression and tropism [10, 11]. In the case of MERSCoV, its RBM binds to DPP4 with residues 484-567, thus, suggesting that its RBD differs from that of SARS-CoV [12, 13]. In a very recent paper, Wan and associates [14] have investigated the receptor recognition by COVID-19 (a new term to indicate the 2019-nCoV in Wuhan) on the bases of structural studies. In this respect, the sequence of COVID-19 RBM is similar to that of SARSCoV, thus, implicating that ACE2 may represent the binding receptors for COVID-19. Furthermore, gln493 residue of COVID-19 RBM seems to allow interaction with human ACE2, thus, suggesting the ability of this virus to infect human cells. According, to Wan and associates structural analysis [14], COVID-19 binds to human ACE2 with a lesser efficiency than human SARS-CoV (2002) but with higher affinity than human SARS-CoV (2003). Furthermore, same authors predicted that a single mutation at the 501 position may enhance the COVID-19 RBD binding capacity to human ACE2 and this evolution should be monitored in infected patients [14]. These predictive findings by Wan and associates [14] are confirmed by two contemporary studies by Letko and Muster [15] and Peng and associates [16]. In particular, the report by Peng and associates [16], points out the possible origin of COVID-19 from bats [16]. From a pathogenic point of view, evidence has been provided that binding of S2 to ACE2 receptor leads to its down-regulation with subsequent lung damage in the course of SARS-CoV infection [17]. Down-regulation of ACE2 causes excessive production of angiotensin (ANG) II by the related enzyme ACE with stimulation of ANG type 1a receptor (AT1R) and enhanced lung vascular permeability [18]. In particular, same authors have reported that recombinant ACE2 could attenuate severe acute lung injury in mice [18]. Moreover, Battle and associates [19] also proposed to use already available recombinant ACE2 for intercepting COVID-19 and attenuating infection. In the previous paragraphs, the presence of ACE2 on immune cells has been pointed out and, by analogy to epithelial cells, this receptor may also be down-regulated following viral entry. Therefore, in CoV-infected animal models and in infected humans further investigations are required to clarify a possible reduced expression of ACE2 on immune cells. In fact, in the course of SARS-CoV infection, a number of immune disorders have been detected. Three reports have demonstrated the ability of CoV to inhibit interferon (IFN)-ï¢ production in the course of SARS acting as IFN antagonist [20-22]. In senescent Balb/c mice, depletion of T lymphocytes is associated to more severe interstitial pneumonitis and delayed clearance of SARS-CoV, thus, suggesting a protective role played by these cells [23]. In this connection, both SARS-CoV and MERS-CoV have been shown to induce T cell apoptosis, thus, aggravating the clinical course of disease [24, 25]. Quite interestingly, memory CD8+ T cells specific for SARS-CoV M and N proteins have been detected up to 11 years post-infection [26]. As far as humoral immune responsiveness is concerned, evidence has been provided that S1 subunit from MERS-CoV is highly immunogenic in mice [27]. Moreover, monoclonal antibodies have been shown to be highly neutralizing against MERS-CoV replication and endowed with post exposure effectiveness in susceptible mice [28, 29]. Human neutralizing antibodies have also been isolated from a recovered patient, thus, suggesting the role of humoral immunity in the control of the persistence of CoV in the host [30]. In particular, IgG response occurs early in infection and its prolonged production may serve for virus clearance during recovery also in view of the absence of viremia in convalescent sera from SARS patients [31]. According to current literature, severity of COVID-19 infection correlates with lymphopenia and patients who died from COVID-19 had lower lymphocyte counts when compared to survivors [32, 33]. These data suggest that lymphocyte-mediated anti-viral activity is poorly effective against COVID-19. Despite lymphopenia, evidence for an exaggerate release of proinflammatory cytokines [interleukin (IL)-1 and IL-6] has been reported in the course acute respiratory syndrome in COVID19 infected patients, thus, aggravating the clinical course of disease [34]. As recently reported, during COVID-19 pandemic in both Italy and China higher frequency of fatalities have been observed in the frail elderly population with previous comorbidities [35]. It is well known that decline of immunity occurs in ageing and, therefore, COVID-19 may gain easier access to the respiratory tract in frail elderly patients [36]. There is evidence that ACE2 protects from severe acute lung failure and operates as a negative regulator of the renin-angiotensin system (RAS) [18, 37]. It is well known that ANG II via activation of the AT1R promotes detrimental effects on the host, such as, vasoconstriction, reactive oxygen species generation, inflammation and matrix remodelling [38]. ACE2 counterbalances the noxious effects exhibited by ANG II and AT1R via activation of AT2R which arrests cell growth, inflammation and fibrosis [39]. In this framework, Gurwitz [40] proposed to use AT1R blockers, such as losartan, as a potential treatment of COVID-19 infection. In fact, losartan as well as olmesartan, used for treating hypertension in patients, were able to increase ACE2 expression after 28 days treatment of rats with myocardial infarction [41]. Then, Gurwitz suggests to evaluate severity of symptoms in COVID-19 infected patients under previous chronic treatment with AT1R blockers in comparison to COVID-19 infected patients who did not take AT1R blockers [40]. Quite interestingly, 75% of aged COVID-19 infected patients admitted to Italian hospitals had hypertension [unpublished data]. However, the putative effects of ACE-2 down-regulation on the cardiovascular system in the course of COVID-19 pandemic need more intensive studies. Taken together, these evidences suggest that CoV-induced down-regulation of ACE2 activates RAS with collateral damage to organs, such as lungs, in the course of SARS-related pneumonia. Then, putative therapeutic measures aimed at increasing ACE2 levels on respiratory epithelial cells should be taken into serious consideration. Quite interestingly, over the past few years, three key papers have demonstrated the ability of a polyphenol, resveratrol (RES), to experimentally deactivate the RAS system in maternal and post-weaning high fat diet, arterial ageing and high fat diet, respectively [42-44]. In all these experimental models, RES led to an increase of ACE2 with reduction of organ damage, such as liver steatosis and aorta media thickness and decrease of adipose tissue mass, respectively. As far as the mechanism of action of RES is concerned, this polyphenol is able to activate sirtuin (Sirt)1 [45-47]. In turn, Sirt1 down-regulates AT1R expression via ACE2 up-regulation [43, 48]. Of importance, Lin and associates [48] have demonstrated the ability of RES to in vitro inhibit MERS-CoV infection of Vero E6 cells, thus, prolonging cell survival in virtue of an anti-apoptotic mechanism. These findings suggest a direct antiviral effect exerted by RES. It would be very interestingly to evaluate the direct effects of RES on COVID-19, in vitro. The data above discussed strongly suggest, that RES, as an activators of ACE2, should be investigated in animal models of CoV-induced severe pneumonia, also taking into account the antioxidant, anti-inflammatory and immunomodulating effects exerted by polyphenols [49]. Then, successful animal studies may pave the way for RES-based human trials in COVID-infected patients. Note added in proof During the reviewing process of this perspective other related papers have been published. Hanff and associates [50] have discussed the possible association between COVID-19-associated cardiovascular mortality and dysregulation of the Renin Angiotensin System (RAS). From a pharmacologic point of view, RAS inhibition leads to upregulation of ACE2, thus, attenuating acute respiratory syndrome and myocarditis in COVID-19-infected patients. Conversely, increase in ACE2 expression may facilitate the access into the host of COVID-19, thus, aggravating the clinical picture. Such a dilemma would be solved byclinical trials based on RAS blockade or initiation and monitoring related effects. Contemporarily, Danser and associates [51] claim that there is no evidence to stop RAS blockers in the course of COVID-19 infection. In fact, there are no available data which support that ACE inhibitors or ANG II type I receptor blockers increase COVID-19 infection via its binding to ACE2. Finally, Kuster and associates [52] write that there are no data on the strict relationship between ACE2 activity and SARS-CoV2 mortality. Moreover, in the SARSCoV2, cells expressing ACE2 were not attacked by the virus, while cells lacking ACE2 were bound by the SARS-CoV2 virus [53]. These findings suggest that also in the case of RES effects on COVID-19 infection, the dual role of ACE2 should be taken into serious consideration.

negative: Use of personal protective equipment against coronavirus disease 2019 by healthcare professionals in Wuhan, China: cross sectional study OBJECTIVE: To examine the protective effects of appropriate personal protective equipment for frontline healthcare professionals who provided care for patients with coronavirus disease 2019 (covid-19). DESIGN: Cross sectional study. SETTING: Four hospitals in Wuhan, China. PARTICIPANTS: 420 healthcare professionals (116 doctors and 304 nurses) who were deployed to Wuhan by two affiliated hospitals of Sun Yat-sen University and Nanfang Hospital of Southern Medical University for 6-8 weeks from 24 January to 7 April 2020. These study participants were provided with appropriate personal protective equipment to deliver healthcare to patients admitted to hospital with covid-19 and were involved in aerosol generating procedures. 77 healthcare professionals with no exposure history to covid-19 and 80 patients who had recovered from covid-19 were recruited to verify the accuracy of antibody testing. MAIN OUTCOME MEASURES: Covid-19 related symptoms (fever, cough, and dyspnoea) and evidence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, defined as a positive test for virus specific nucleic acids in nasopharyngeal swabs, or a positive test for IgM or IgG antibodies in the serum samples. RESULTS: The average age of study participants was 35.8 years and 68.1% (286/420) were women. These study participants worked 4-6 hour shifts for an average of 5.4 days a week; they worked an average of 16.2 hours each week in intensive care units. All 420 study participants had direct contact with patients with covid-19 and performed at least one aerosol generating procedure. During the deployment period in Wuhan, none of the study participants reported covid-19 related symptoms. When the participants returned home, they all tested negative for SARS-CoV-2 specific nucleic acids and IgM or IgG antibodies (95% confidence interval 0.0 to 0.7%). CONCLUSION: Before a safe and effective vaccine becomes available, healthcare professionals remain susceptible to covid-19. Despite being at high risk of exposure, study participants were appropriately protected and did not contract infection or develop protective immunity against SARS-CoV-2. Healthcare systems must give priority to the procurement and distribution of personal protective equipment, and provide adequate training to healthcare professionals in its use.

negative: A model of bi-mode transmission dynamics of hepatitis C with optimal control In this paper, we present a rigorous mathematical analysis of a deterministic model for the transmission dynamics of hepatitis C. The model is suitable for populations where two frequent modes of transmission of hepatitis C virus, namely unsafe blood transfusions and intravenous drug use, are dominant. The susceptible population is divided into two distinct compartments, the intravenous drug users and individuals undergoing unsafe blood transfusions. Individuals belonging to each compartment may develop acute and then possibly chronic infections. Chronically infected individuals may be quarantined. The analysis indicates that the eradication and persistence of the disease is completely determined by the magnitude of basic reproduction number R (c). It is shown that for the basic reproduction number R (c) < 1, the disease-free equilibrium is locally and globally asymptotically stable. For R (c) > 1, an endemic equilibrium exists and the disease is uniformly persistent. In addition, we present the uncertainty and sensitivity analyses to investigate the influence of different important model parameters on the disease prevalence. When the infected population persists, we have designed a time-dependent optimal quarantine strategy to minimize it. The Pontryagin’s Maximum Principle is used to characterize the optimal control in terms of an optimality system which is solved numerically. Numerical results for the optimal control are compared against the constant controls and their efficiency is discussed.

negative: 2019-novel coronavirus outbreak: A new challenge OBJECTIVES: Following the public health emergency declared by the World Health Organization and the recent outbreak by 2019-nCoV in China and through other 29 countries, we aimed to summarize the clinical aspects of novel beta-coronavirus infection and its possible clinical presentations together with suggested therapeutic algorithms for patients who may require antibiotic treatment. METHODS: We reviewed the currently available literature of microbiologically confirmed infections by 2019-ConV (or COVID-19) occurred at the time of writing (13 February 2020). A literature search was performed using the PubMed database and the Cochrane library. Search terms included "novel coronavirus" or "2019-nCoV" or “COVID-19”. RESULTS: Published cases occurred mostly in males (age ranged from 8 to 92). Cardiovascular, digestive and endocrine system diseases were commonly reported, except previous chronic pulmonary diseases (e.g., COPD, asthma, bronchiectasis) that were surprisingly underreported. Fever was presented in all the case series available, flanked by cough, dyspnea, myalgias and fatigue. Multiple bilateral lobular and subsegmental areas of consolidation or bilateral ground-glass opacities were the main reported radiological features of 2019-nCoV, at least in the early phases of disease. CONCLUSIONS: The new 2019-nCoV epidemics is mainly associated with respiratory disease and few extrapulmonary signs. However, there is a low rate of associated pre-existing respiratory comorbidities.

negative: Modified Vaccinia Virus Ankara (MVA) as Production Platform for Vaccines against Influenza and Other Viral Respiratory Diseases Respiratory viruses infections caused by influenza viruses, human parainfluenza virus (hPIV), respiratory syncytial virus (RSV) and coronaviruses are an eminent threat for public health. Currently, there are no licensed vaccines available for hPIV, RSV and coronaviruses, and the available seasonal influenza vaccines have considerable limitations. With regard to pandemic preparedness, it is important that procedures are in place to respond rapidly and produce tailor made vaccines against these respiratory viruses on short notice. Moreover, especially for influenza there is great need for the development of a universal vaccine that induces broad protective immunity against influenza viruses of various subtypes. Modified Vaccinia Virus Ankara (MVA) is a replication-deficient viral vector that holds great promise as a vaccine platform. MVA can encode one or more foreign antigens and thus functions as a multivalent vaccine. The vector can be used at biosafety level 1, has intrinsic adjuvant capacities and induces humoral and cellular immune responses. However, there are some practical and regulatory issues that need to be addressed in order to develop MVA-based vaccines on short notice at the verge of a pandemic. In this review, we discuss promising novel influenza virus vaccine targets and the use of MVA for vaccine development against various respiratory viruses.

negative: Potent Zika and dengue cross-neutralizing antibodies induced by Zika vaccination in a dengue-experienced donor Zika virus (ZIKV) has caused significant disease, with widespread cases of neurological pathology and congenital neurologic defects. Rapid vaccine development has led to a number of candidates capable of eliciting potent ZIKV-neutralizing antibodies (reviewed in refs. (1–3)). Despite advances in vaccine development, it remains unclear how ZIKV vaccination affects immune responses in humans with prior flavivirus immunity. Here we show that a single-dose immunization of ZIKV purified inactivated vaccine (ZPIV)(4–7) in a dengue virus (DENV)-experienced human elicited potent cross-neutralizing antibodies to both ZIKV and DENV. Using a unique ZIKV virion-based sorting strategy, we isolated and characterized multiple antibodies, including one termed MZ4, which targets a novel site of vulnerability centered on the Envelope (E) domain I/III linker region and protects mice from viremia and viral dissemination following ZIKV or DENV-2 challenge. These data demonstrate that Zika vaccination in a DENV-experienced individual can boost pre-existing flavivirus immunity and elicit protective responses against both ZIKV and DENV. ZPIV vaccination in Puerto Rican individuals with prior flavivirus experience yielded similar cross-neutralizing potency after a single vaccination, highlighting the potential benefit of ZIKV vaccination in flavivirus-endemic areas.

negative: Insight Derived from Molecular Docking and Molecular Dynamics Simulations into the Binding Interactions Between HIV-1 Protease Inhibitors and SARS-CoV-2 3CLpro A novel severe acute respiratory syndrome coronavirus (SARS-CoV-2) was identified from respiratory illness patients in Wuhan, Hubei Province, China, which has recently emerged as a serious threat to the world public health Hower, no approved drugs have been found to effectively inhibit the virus Since it has been reported that the HIV-1 protease inhibitors can be used as anti-SARS drugs by tegarting SARS-CoV 3CLpro, we choose six approved anti-HIV-1 drugs to investigate their binding interactions between 3CLpro, and to evaluate their potential to become clinical drugs for the new coronavirus pneumonia (COVID19) caused by SARS-CoV-2 infection The molecular docking results indicate that, the 3CLpro of SARS-CoV-2 has a higher binding affinity for all the studied inhibitors than its SARS homologue Two docking complexes (indinavir and darunavir) with high docking scores were futher subjected to MM-PBSA binding free energy calculations to detail the molecular interactions between these two proteinase inhibitors and the 3CLpro Our results show that darunavir has the best binding affinity with SARS-CoV-2 and SARS-CoV 3CLpro among all inhibitors, indicating it has the potential to become an anti-COVID-19 clinical drug The likely reason behind the increased binding affinity of HIV-1 protease inhibitors toward SARS-CoV2 3CLpro than that of SARS-CoV were investigated by MD simulations Our study provides insight into the possible role of structural flexibility during interactions between 3CLpro and inhibitors, and sheds light on the structure-based design of anti-COVID-19 drugs targeting the SARS-CoV-2 3CLpro

negative: Repurposing Therapeutics for COVID-19: Rapid Prediction of Commercially available drugs through Machine Learning and Docking Background The outbreak of the novel coronavirus disease COVID 19, caused by the SARS-CoV-2 virus has spread rapidly around the globe during the past 3 months. As the virus infected cases and mortality rate of this disease is increasing exponentially, scientists and researchers all over the world are relentlessly working to understand this new virus along with possible treatment regimens by discovering active therapeutic agents and vaccines. So, there is an urgent requirement of new and effective medications that can treat the disease caused by SARS CoV 2. Methods and findings We perform the study of drugs that are already available in the market and being used for other diseases to accelerate clinical recovery, in other words repurposing of existing drugs. The vast complexity in drug design and protocols regarding clinical trials often prohibit developing various new drug combinations for this epidemic disease in a limited time. Recently, remarkable improvements in computational power coupled with advancements in Machine Learning (ML) technology have been utilized to revolutionize the drug development process. Consequently, a detailed study using ML for the repurposing of therapeutic agents is urgently required. Here, we report the ML model based on the Naive Bayes algorithm, which has an accuracy of around 73% to predict the drugs that could be used for the treatment of COVID-19. Our study predicts around ten FDA approved commercial drugs that can be used for repurposing. Among all, we suggest that the antiretroviral drug Atazanavir (DrugBank ID DB01072) would probably be one of the most effective drugs based on the selected criterions. Conclusions Our study can help clinical scientists in being more selective in identifying and testing the therapeutic agents for COVID 19 treatment. The ML based approach for drug discovery as reported here can be a futuristic smart drug designing strategy for community applications.

negative: A modified SEIR model to predict the COVID-19 outbreak in Spain and Italy: simulating control scenarios and multi-scale epidemics After the spread of SARS-CoV-2 epidemic out of China, evolution in the pandemic worldwide shows dramatic differences among countries. In Europe, the situation of Italy first and later Spain has generated great concern, and despite other countries show better prospects, large uncertainties yet remain on the future evolution and the efficacy of containment, mitigation or attack strategies. Here we applied a modified SEIR compartmental model accounting for the spread of infection during the latent period, in which we also incorporate effects of varying proportions of containment. We fit data to quarantined populations in order to account for the uncertainties in case reporting and study the scenario projections for the 17 individual regions (CCAA). Results indicate that with data for March 23, the epidemics follow an evolution similar to the isolation of 1,5 percent of the population and if there were no effects of intervention actions it might reach a maximum of over 1.4M infected around April 27. The effect on the epidemics of the ongoing partial confinement measures is yet unknown (an update of results with data until March 31st is included), but increasing the isolation around ten times more could drastically reduce the peak to over 100k cases by early April, while each day of delay in taking this hard containment scenario represents a 90 percent increase of the infected population at the peak. Dynamics at the sub aggregated levels of CCAA show epidemics at the different levels of progression with the most worrying situation in Madrid an Catalonia. Increasing alpha values up to 10 times, in addition to a drastic reduction in clinical cases, would also more than halve the number of deaths. Updates for March 31st simulations indicate a substantial reduction in burden is underway. A similar approach conducted for Italy pre- and post-interventions also begins to suggest substantial reduction in both infected and deaths has been achieved, showing the efficacy of drastic social distancing interventions.

negative: Neutralizing Antibodies against SARS-CoV-2 and Other Human Coronaviruses Coronavirus (CoV) disease 2019 (COVID-19) caused by severe acute respiratory syndrome (SARS)-CoV-2 (also known as 2019-nCoV) is threatening global public health, social stability, and economic development. To meet this challenge, this article discusses advances in the research and development of neutralizing antibodies (nAbs) for the prevention and treatment of infection by SARS-CoV-2 and other human CoVs.

negative: Protective immunity to lethal challenge of the 1918 pandemic influenza virus by vaccination. The remarkable infectivity and virulence of the 1918 influenza virus resulted in an unprecedented pandemic, raising the question of whether it is possible to develop protective immunity to this virus and whether immune evasion may have contributed to its spread. Here, we report that the highly lethal 1918 virus is susceptible to immune protection by a preventive vaccine, and we define its mechanism of action. Immunization with plasmid expression vectors encoding hemagglutinin (HA) elicited potent CD4 and CD8 cellular responses as well as neutralizing antibodies. Antibody specificity and titer were defined by a microneutralization and a pseudotype assay that could assess antibody specificity without the need for high-level biocontainment. This pseudotype inhibition assay can define evolving serotypes of influenza viruses and facilitate the development of immune sera and neutralizing monoclonal antibodies that may help contain pandemic influenza. Notably, mice vaccinated with 1918 HA plasmid DNAs showed complete protection to lethal challenge. T cell depletion had no effect on immunity, but passive transfer of purified IgG from anti-H1(1918) immunized mice provided protective immunity for naïve mice challenged with infectious 1918 virus. Thus, humoral immunity directed at the viral HA can protect against the 1918 pandemic virus.

negative: Host resilience to emerging coronaviruses Recently, two coronaviruses, severe acute respiratory syndrome coronavirus and Middle East respiratory syndrome coronavirus, have emerged to cause unusually severe respiratory disease in humans. Currently, there is a lack of effective antiviral treatment options or vaccine available. Given the severity of these outbreaks, and the possibility of additional zoonotic coronaviruses emerging in the near future, the exploration of different treatment strategies is necessary. Disease resilience is the ability of a given host to tolerate an infection, and to return to a state of health. This review focuses on exploring various host resilience mechanisms that could be exploited for treatment of severe acute respiratory syndrome coronavirus, Middle East respiratory syndrome coronavirus and other respiratory viruses that cause acute lung injury and acute respiratory distress syndrome.

negative: The value of mitigating epidemic peaks of COVID-19 for more effective public health responses

negative: Molecular mechanisms of primary and secondary mucosal immunity using avian infectious bronchitis virus as a model system Abstract Although mucosal immune responses are critical for protection of hosts from clinical illness and even mortality caused by mucosal pathogens, the molecular mechanism of mucosal immunity, which is independent of systemic immunity, remains elusive. To explore the mechanistic basis of mucosal protective immunity, gene transcriptional profiling in mucosal tissues was evaluated after the primary and secondary immunization of animals with an attenuated avian infectious bronchitis virus (IBV), a prototype of Coronavirus and a well-characterized mucosal pathogen. Results showed that a number of innate immune factors including toll-like receptors (TLRs), retinoic-acid-inducible gene-1 (RIG-1), type I interferons (IFNs), complements, and interleukin-1 beta (IL-1β) were activated locally after the primary immunization. This was accompanied or immediately followed by a potent Th1 adaptive immunity as evidenced by the activation of T-cell signaling molecules, surface markers, and effector molecules. A strong humoral immune response as supported by the significantly up-regulated immunoglobulin (Ig) gamma chain was observed in the absence of innate, Th1 adaptive immunity, or IgA up-regulation after the secondary immunization, indicating that the local memory response is dominated by IgG. Overall, the results provided the first detailed kinetics on the molecular basis underlying the development of primary and secondary mucosal immunity. The key molecular signatures identified may provide new opportunities for improved prophylactic and therapeutic strategies to combat mucosal infections.

negative: Benefit-risk analysis of health benefits of routine childhood immunisation against the excess risk of SARS-CoV-2 infections during the Covid-19 pandemic in Africa Background: National immunisation programmes globally are at risk of suspension due to the severe health system constraints and physical distancing measures in place to mitigate the ongoing COVID-19 pandemic. Our aim is to compare the health benefits of sustaining routine childhood immunisation in Africa against the risk of acquiring SARS-CoV-2 infections through visiting routine vaccination service delivery points. Methods: We used two scenarios to approximate the child deaths that may be caused by immunisation coverage reductions during COVID-19 outbreaks. First, we used previously reported country-specific child mortality impact estimates of childhood immunisation for diphtheria, tetanus, pertussis, hepatitis B, Haemophilus influenzae type b, pneumococcal, rotavirus, measles, meningitis A, rubella, and yellow fever (DTP3, HepB3, Hib3, PCV3, RotaC, MCV1, MCV2, MenA, RCV, YFV) to approximate the future deaths averted before completing five years of age by routine childhood vaccination during a 6-month Covid-19 risk period without catch-up campaigns. Second, we analysed an alternative scenario that approximates the health benefits of sustaining routine childhood immunisation to only the child deaths averted from measles outbreaks during the Covid-19 risk period. The excess number of infections due to additional SARS-CoV-2 exposure during immunisation visits assumes that contact reducing interventions flatten the outbreak curve during the Covid-19 risk period, that 60% of the population will have been infected by the end of that period, that children can be infected by either vaccinators or during transport and that upon child infection the whole household would be infected. Country specific household age structure estimates and age dependent infection fatality rates are then applied to calculate the number of deaths attributable to the vaccination clinic visits. We present benefit-risk ratios for routine childhood immunisation alongside 95% uncertainty range estimates from probabilistic sensitivity analysis. Findings: For every one excess Covid-19 death attributable to SARS-CoV-2 infections acquired during routine vaccination clinic visits, there could be 143 (38 - 576) deaths in children prevented by sustaining routine childhood immunisation in Africa. The benefit-risk ratio for the vaccinated children, siblings, parents or adult care-givers, and older adults in the households of vaccinated children are 58,000 (3,200 - 21,350,000), 52,000 (2,800 - 18,884,000), 2,000 (393 - 12,000), and 157 (41 - 652) respectively. In the alternative scenario that approximates the health benefits to only the child deaths averted from measles outbreaks, the benefit-risk ratio to the households of vaccinated children is 5 (1 - 21) under these highly conservative assumptions and if the risk to only the vaccinated children is considered, the benefit-risk ratio is 2,000 (131 - 839,000). Interpretation: Our analysis suggests that the health benefits of deaths prevented by sustaining routine childhood immunisation in Africa far outweighs the excess risk of Covid-19 deaths associated with vaccination clinic visits. However, there are other factors that must be considered for strategic decision making to sustain routine childhood immunisation in African countries during the Covid-19 pandemic. These include logistical constraints of vaccine supply chain problems caused by the Covid-19 pandemic, reallocation of immunisation providers to other prioritised health services, healthcare staff shortages caused by SARS-CoV-2 infections among the staff, decreased demand for vaccination arising from community reluctance to visit vaccination clinics for fear of contracting SARS-CoV-2 infections, and infection risk to healthcare staff providing immunisation services as well as to their households and onward SARS-CoV-2 transmission into the wider community.

negative: The outbreak of SARS-CoV-2 pneumonia calls for viral vaccines The outbreak of 2019-novel coronavirus disease (COVID-19) that is caused by SARS-CoV-2 has spread rapidly in China, and has developed to be a Public Health Emergency of International Concern However, no specific antiviral treatments or vaccines are available yet This work aims to share strategies and candidate antigens to develop safe and effective vaccines against SARS-CoV-2 An outbreak of 2019-novel coronavirus (SARS-CoV-2) that causes atypical pneumonia (COVID-19) has raged in China since mid-December 2019 and has spread to 26 countries (February 20, 2020) The epidemic was identified by the first four cases confirmed on December 29, 2019 and was traced to the Huanan Seafood Wholesale Market, Wuhan city, Hubei Province, China1 A total of 75,465 cases with SARS-CoV-2 infections have been confirmed up to date (February 20, 2020), and 2,236 people have died in China2 COVID-19 spreads rapidly by human-to-human transmission with a median incubation period of 3 0 days (range, 0 to 24 0), and the time from symptom onset to developing pneumonia is 4 0 days (range, 2 0 to 7 0)3 Respiratory droplets and direct contact are conventional transmission routes for SARS-CoV-2, and fecal-to-oral transmission might also have a role3 Fever, dry cough, and fatigue are common symptoms at onset of COVID-194 Most patients have lymphopenia and bilateral ground-glass opacity changes on chest CT scans4,5 No specific antiviral treatments or vaccines are available because it is a new emerging viral disease Development of SARS-CoV-2-based vaccines is urgently required The entire virus particle-based preparation of vaccines, including inactivated and attenuated virus vaccines is advisable, because it is based on previous studies about the prevention and control of seasonal influenza vaccines6 The first SARS-CoV-2 (Wuhan-Hu-1) was successfully sequenced and its genomic sequence submitted to GenBank on January 5, 2020 (Accession no MN908947 3)7 Subsequently large-scale culture of SARS-CoV-2 was quickly performed, and an inactivated virus vaccine could be prepared through the employment of established physical and chemical methods such as UV light, formaldehyde, and β-propiolactone8 The development of attenuated-virus vaccines is also possible by carefully screening the serially propagated SARS-CoV-2 with reduced pathogenesis such as induced minimal lung injury, diminished limited neutrophil influx, and increased anti-inflammatory cytokine expressions compared with the wild-type virus9 Both inactivated and attenuated virus vaccines have their own disadvantages and side effects (Table 1) Alternatively, new vaccine designs based on the putative protective antigen/peptides derived from SARS-CoV-2 should be considered

negative: Evidence of the COVID-19 Virus Targeting the CNS: Tissue Distribution, Host–Virus Interaction, and Proposed Neurotropic Mechanisms [Image: see text] The recent outbreak of coronavirus infectious disease 2019 (COVID-19) has gripped the world with apprehension and has evoked a scare of epic proportion regarding its potential to spread and infect humans worldwide. As we are in the midst of an ongoing pandemic of COVID-19, scientists are struggling to understand how it resembles and differs from the severe acute respiratory syndrome coronavirus (SARS-CoV) at the genomic and transcriptomic level. In a short time following the outbreak, it has been shown that, similar to SARS-CoV, COVID-19 virus exploits the angiotensin-converting enzyme 2 (ACE2) receptor to gain entry inside the cells. This finding raises the curiosity of investigating the expression of ACE2 in neurological tissue and determining the possible contribution of neurological tissue damage to the morbidity and mortality caused by COIVD-19. Here, we investigate the density of the expression levels of ACE2 in the CNS, the host–virus interaction and relate it to the pathogenesis and complications seen in the recent cases resulting from the COVID-19 outbreak. Also, we debate the need for a model for staging COVID-19 based on neurological tissue involvement.

negative: The different clinical characteristics of corona virus disease cases between children and their families in China – the character of children with COVID-19 This study aims to analyze the different clinical characteristics between children and their families infected with severe acute respiratory syndrome coronavirus 2. Clinical data from nine children and their 14 families were collected, including general status, clinical, laboratory test, and imaging characteristics. All the children were detected positive result after their families onset. Three children had fever (22.2%) or cough (11.2%) symptoms and six (66.7%) children had no symptom. Among the 14 adult patients, the major symptoms included fever (57.1%), cough (35.7%), chest tightness/pain (21.4%), fatigue (21.4%) and sore throat (7.1%). Nearly 70% of the patients had normal (71.4%) or decreased (28.6%) white blood cell counts, and 50% (7/14) had lymphocytopenia. There were 10 adults (71.4%) showed abnormal imaging. The main manifestations were pulmonary consolidation (70%), nodular shadow (50%), and ground glass opacity (50%). Five discharged children were admitted again because their stool showed positive result in SARS-CoV-2 PCR. COVID-19 in children is mainly caused by family transmission, and their symptoms are mild and prognosis is better than adult. However, their PCR result in stool showed longer time than their families. Because of the mild or asymptomatic clinical process, it is difficult to recognize early for pediatrician and public health staff.

negative: COVID-19 randomised trial protocols: rapid publication without barriers

negative: Application of an Amine Functionalized Biopolymer in the Colonic Delivery of Glycyrrhizin: A Design and In Vivo Efficacy Study In our current study, a newer amine functionalized guar gum derivative was studied for its efficacy in colonic drug delivery. Glycyrrhizic acid mono-ammonium salt was used as the model drug. Drug-loaded microparticles were formulated by ionic crosslinking using sodium tripolyphosphate. The Scanning Electron Microscopic study revealed spherical particles of sizes from 4.9 ± 3.8 μm to 6.9 ± 3.9 μm. The FT-IR studies presented a possible interaction between the drug and the polymer. The drug was encapsulated in amorphous form as observed from the powder X-Ray Diffraction studies. A cumulative drug release study was carried out in simulated gastric, intestinal, and colonic fluids. The cumulative drug release studies presented a burst release followed by a sustained release of the drug in simulated colonic fluid containing rat cecal contents. The drug-polymer ratio was optimised using a 3(2) factorial design by taking the amounts of glycyrrhizic acid (X(1)) and guar gum alkyl amine (X(2)) as the independant variables. The percent cumulative drug release at 240 mins (Q(240)), 720 mins (Q(720)), and at 1,440 mins (Q(1440)) were considered as the dependant variables. The efficacy of the optimized formulation was studied in a 2,4,6-trinitrobenzene sulfonic acid-induced rat colitis model. The tissue’s nitric oxide, malondialdehyde, and myeloperoxidase activities were found to be much lower in the microparticle-treated group compared to free drug-treated group. The histology of the colonic tissue from the treated group of animals revealed almost no infiltration of inflammatory cells in the tissue for the microparticle-treated group of animals. The synthesized amine derivative of guar gum was found to be better in vitro with a better in vivo efficacy in the colonic delivery of glycyrrhizic acid monoammonium salt and can be considered as a newer modified biopolymer for colonic drug delivery.

negative: Epidemiological impact of SARS-CoV-2 vaccination: mathematical modeling analyses Background: Several SARS-CoV-2 vaccine candidates are currently in the pipeline. This study aims to inform SARS-CoV-2 vaccine development, licensure, decision-making, and implementation by determining key preferred vaccine product characteristics and associated population-level impact. Methods: Vaccination impact was assessed at various efficacies using an age-structured mathematical model describing SARS-CoV-2 transmission and disease progression, with application for China. Results: A prophylactic vaccine with efficacy against acquisition (VEs) of ≥70% is needed to eliminate this infection. A vaccine with VEs <70% will still have a major impact, and may control the infection if it reduces infectiousness or infection duration among those vaccinated who acquire the infection, or alternatively if supplemented with a moderate social-distancing intervention (<20% reduction in contact rate), or complemented with herd immunity. Vaccination is cost-effective. For a vaccine with VEs of 50%, number of vaccinations needed to avert one infection is only 2.4, one severe disease case is 25.5, one critical disease case is 33.2, and one death is 65.1. Gains in effectiveness are achieved by initially prioritizing those ≥60 years. Probability of a major outbreak is virtually zero with a vaccine with VEs ≥70%, regardless of number of virus introductions. Yet, an increase in social contact rate among those vaccinated (behavior compensation) can undermine vaccine impact. Conclusions: Even a partially-efficacious vaccine can offer a fundamental solution to control SARS-CoV-2 infection and at high cost-effectiveness. In addition to the primary endpoint on infection acquisition, developers should assess natural history and disease progression outcomes and/or proxy biomarkers, since such secondary endpoints may prove critical in licensure, decision-making, and vaccine impact.

negative: Might the many positive COVID19 subjects in Italy have been caused by resident bat‐derived zoonotic β‐coronaviruses instead of the Wuhan (China) outbreak?

negative: The missing pieces in the jigsaw and need for cohesive research amidst COVID 19 global response

negative: Improving Cross-Protection against Influenza Virus Using Recombinant Vaccinia Vaccine Expressing NP and M2 Ectodomain Tandem Repeats Conventional influenza vaccines need to be designed and manufactured yearly. However, they occasionally provide poor protection owing to antigenic mismatch. Hence, there is an urgent need to develop universal vaccines against influenza virus. Using nucleoprotein (NP) and extracellular domain of matrix protein 2 (M2e) genes from the influenza A virus A/Beijing/30/95 (H3N2), we constructed four recombinant vaccinia virus-based influenza vaccines carrying NP fused with one or four copies of M2e genes in different orders. The recombinant vaccinia viruses were used to immunize BALB/C mice. Humoral and cellular responses were measured, and then the immunized mice were challenged with the influenza A virus A/Puerto Rico/8/34 (PR8). NP-specific humoral response was elicited in mice immunized with recombinant vaccinia viruses carrying full-length NP, while robust M2e-specific humoral response was elicited only in the mice immunized with recombinant vaccinia viruses carrying multiple copies of M2e. All recombinant viruses elicited NP- and M2e-specific cellular immune responses in mice. Only immunization with RVJ-4M2eNP induced remarkably higher levels of IL-2 and IL-10 cytokines specific to M2e. Furthermore, RVJ-4M2eNP immunization provided the highest cross-protection in mice challenged with 20 MLD(50) of PR8. Therefore, the cross-protection potentially correlates with both NP and M2e-specific humoral and cellular immune responses induced by RVJ-4M2eNP, which expresses a fusion antigen of full-length NP preceded by four M2e repeats. These results suggest that the rational fusion of NP and multiple M2e antigens is critical toward inducing protective immune responses, and the 4M2eNP fusion antigen may be employed to develop a universal influenza vaccine. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s12250-019-00138-9) contains supplementary material, which is available to authorized users.

negative: Treatment and vaccines for severe acute respiratory syndrome Summary The causative agent of severe acute respiratory syndrome (SARS), which affected over 8000 individuals worldwide and was responsible for over 700 deaths in the 2002–2003 outbreak, is a coronavirus that was unknown before the outbreak. Although many different treatments were used during the outbreak, none were implemented in a controlled fashion. Thus, the optimal treatment for SARS is unknown. Since the outbreak, much work has been done testing new agents against SARS using in-vitro methods and animal models. In addition, global research efforts have focused on the development of vaccines against SARS. Efforts should be made to evaluate the most promising treatments and vaccines in controlled clinical trials, should another SARS outbreak occur.

negative: Periodic Graphics: How does immunity work? Chemical educator and Compound Interest blogger Andy Brunning explains how our bodies fight foreign invaders like coronaviruses To download a pdf of this article, visit http://cenm ag/immunity References used to create this graphic:Centers for Disease Control and Prevention Understanding How Vaccines Work Last updated July 2018 Janeway, Charles A , Jr , Paul Travers, Mark Walport, and Mark J Shlomchik “The Distribution and Functions of Immunoglobulin Isotypes ” In Immunobiology: The Immune System in Health and Disease 5th ed New York: Garland Science, 2001 Li, Geng, Yaohua Fan, Yanni Lai, et al “Coronavirus Infections and Immune Responses ”J Med Virol (Jan 2020) DOI: 10 1002/jmv 25685 National Institute of Allergy and Infectious Diseases and National Cancer Institute Understanding the Immune System: How It Works US Department of Health and Human Services, National Institutes of Health, 2003 Siegrist , Claire-Anne “Vaccine Immunology ” In Plotkin’s Vaccines 7th ed Edited by Stanley A Plotkin, Walter A Orenstein, Paul A Offit, and

negative: Protective Efficacy of Cross-Reactive CD8(+) T Cells Recognising Mutant Viral Epitopes Depends on Peptide-MHC-I Structural Interactions and T Cell Activation Threshold Emergence of a new influenza strain leads to a rapid global spread of the virus due to minimal antibody immunity. Pre-existing CD8(+) T-cell immunity directed towards conserved internal viral regions can greatly ameliorate the disease. However, mutational escape within the T cell epitopes is a substantial issue for virus control and vaccine design. Although mutations can result in a loss of T cell recognition, some variants generate cross-reactive T cell responses. In this study, we used reverse genetics to modify the influenza NP(336–374) peptide at a partially-solvent exposed residue (N->A, NPN3A mutation) to assess the availability, effectiveness and mechanism underlying influenza-specific cross-reactive T cell responses. The engineered virus induced a diminished CD8(+) T cell response and selected a narrowed T cell receptor (TCR) repertoire within two Vβ regions (Vβ8.3 and Vβ9). This can be partially explained by the H-2D(b)NPN3A structure that showed a loss of several contacts between the NPN3A peptide and H-2D(b), including a contact with His155, a position known to play an important role in mediating TCR-pMHC-I interactions. Despite these differences, common cross-reactive TCRs were detected in both the naïve and immune NPN3A-specific TCR repertoires. However, while the NPN3A epitope primes memory T-cells that give an equivalent recall response to the mutant or wild-type (wt) virus, both are markedly lower than wt->wt challenge. Such decreased CD8(+) responses elicited after heterologous challenge resulted in delayed viral clearance from the infected lung. Furthermore, mice first exposed to the wt virus give a poor, low avidity response following secondary infection with the mutant. Thus, the protective efficacy of cross-reactive CD8(+) T cells recognising mutant viral epitopes depend on peptide-MHC-I structural interactions and functional avidity. Our study does not support vaccine strategies that include immunization against commonly selected cross-reactive variants with mutations at partially-solvent exposed residues that have characteristics comparable to NPN3A.

negative: Delayed clearance of SARS-CoV2 in male compared to female patients: High ACE2 expression in testes suggests possible existence of gender-specific viral reservoirs The novel coronavirus SARS-CoV2 has been observed to cause a higher incidence and greater severity of disease in males, as seen in multiple cohorts across the globe. The reasons for gender disparity in disease severity is unclear and can be due to host factors. To determine whether males have delayed viral clearance after infection, we evaluated the time to clearance in symptomatic patients tested by serial oropharyngeal/nasopharyngeal swabs followed by RT-PCR at a reference lab in Mumbai, India. A total of 68 subjects with median age of 37 years (3-75 range) were examined and included 48 (71%) males and 20 (29%) females. We observed that females were able to achieve viral clearance significantly earlier than males, with a median difference of 2 days in achieving a negative PCR result (P value = 0.038). Furthermore, examination of 3 families with both male and female patients followed serially, demonstrated that female members of the same household cleared the SARS-CoV2 infection earlier in each family. To determine reasons for delayed clearance in males, we examined the expression patterns of the SARS-CoV2 receptor, Angiotensin-converting enzyme 2 (ACE2), in tissue specific repositories. We observed that the testes was one of the highest sites of ACE2 expression in 3 independent RNA expression databases (Human Protein Atlas, FAMTOM5 and GETx). ACE2 was also determined to be highly expressed in testicular cells at the protein levels. Interestingly, very little expression of ACE2 was seen in ovarian tissue. Taken together, these observations demonstrate for the first time that male subjects have delayed viral clearance of SARS-CoV2. High expression of ACE2 in testes raises the possibility that testicular viral reservoirs may play a role in viral persistence in males and should be further investigated.

negative: Sows infected in pregnancy with porcine respiratory coronavirus show no evidence of protecting their sucking piglets against transmissible gastroenteritis Eighteen litters of sucking piglets were challenged with one of two strains of transmissible gastroenteritis virus (TGEV). During pregnancy, their seronegative dams had been either inoculated intranasally with porcine respiratory coronavirus (PRCV), inoculated orally with TGEV or left untreated. On the basis of weight gain, clinical signs and survival, no differences in response to challenge was detected when piglets suckled by PRCV inoculated sows were compared with those suckled by uninoculated sows. Such a difference was evident when the litters of sows successfully pre-immunized with TGEV were compared with those of unicoculated or PRCV-inoculated sows. The possibility of transplacental transmission of PRCV was investigated in two litters born to sows that had been inoculated with this virus in late pregnancy. All sixteen live-born piglets were seronegative for the virus at birth and PRCV was not isolated from tissues taken from two stillborn piglets.

negative: Advances in the treatment of virus-induced asthma Viral exacerbations continue to represent the major burden in terms of morbidity, mortality and health care costs associated with asthma. Those at greatest risk for acute asthma are those with more severe airways disease and poor asthma control. It is this group with established asthma in whom acute exacerbations triggered by virus infections remain a serious cause of increased morbidity. A range of novel therapies are emerging to treat asthma and in particular target this group with poor disease control, and in most cases their efficacy is now being judged by their ability to reduce the frequency of acute exacerbations. Critical for the development of new treatment approaches is an improved understanding of virus-host interaction in the context of the asthmatic airway. This requires research into the virology of the disease in physiological models in conjunction with detailed phenotypic characterisation of asthma patients to identify targets amenable to therapeutic intervention.

negative: Blocking of the CD80/86 axis as a therapeutic approach to prevent progression to more severe forms of COVID-19 In its more severe forms, COVID-19 progresses towards an excessive immune response, leading to the systemic overexpression of proinflammatory cytokines like IL6, mostly from the infected lungs. This cytokine storm can cause multiple organ damage and death. Consequently, there is a pressing need to identify therapies to treat and prevent severe symptoms during COVID-19. Based on previous clinical evidence, we hypothesized that inhibiting T cell co-stimulation by blocking CD80/86 could be an effective therapeutic strategy against progression to severe proinflammatory states. To support this hypothesis, we performed an analysis integrating blood transcriptional data we generated from rheumatoid arthritis patients treated with abatacept -- a CD80/86 co-stimulation inhibitor -- with the pathological features associated with COVID-19, particularly in its more severe forms. We have found that many of the biological processes that have been consistently associated with COVID-19 pathology are reversed by CD80/86 co-stimulation inhibition, including the downregulation of IL6 production. Also, analysis of previous transcriptional data from blood of SARS-CoV-infected patients showed that the response to abatacept has a very high level of antagonism to that elicited by COVID-19. Finally, analyzing a recent single cell RNA-seq dataset from bronchoalveolar lavage fluid cells from COVID-19 patients, we found a significant correlation along the main elements of the C80/86 axis: CD86+/80+ antigen presenting cells, activated CD4+ T cells and IL6 production. Our in-silico study provides additional support to the hypothesis that blocking of the CD80/CD86 signaling axis may be protective of the excessive proinflammatory state associated with COVID-19 in the lungs.

negative: Seizures associated with coronavirus infections Neurotropic and neuroinvasive capabilities of coronaviruses have been described in humans. Neurological problems found in patients with coronavirus infection include: febrile seizures, convulsions, loss of consciousness, encephalomyelitis, and encephalitis. Coronavirus disease (COVID-19) is caused by SARS-COV2. In severe cases, patients may develop severe pneumonia, acute respiratory distress syndrome, and acute cardiac injury. While seizures and status epilepticus have not been widely reported in the past five months since the onset of COVID-19 pandemic, patients with COVID-19 may have hypoxia, multiorgan failure, and severe metabolic and electrolyte disarrangements; hence, it is plausible to expect clinical or subclinical acute symptomatic seizures to happen in these patients. One should be prepared to treat seizures appropriately, if they happen in a patient who is already in a critical medical condition and suffers from organ failure.

negative: The underpinning biology relating to multiple sclerosis disease modifying treatments during the COVID-19 pandemic. BACKGROUND: : SARS-CoV-2 viral infection causes COVID-19 that can result in severe acute respiratory distress syndrome (ARDS), which can cause significant mortality, leading to concern that immunosuppressive treatments for multiple sclerosis and other disorders have significant risks for both infection and ARDS. OBJECTIVE: : To examine the biology that potentially underpins immunity to the SARS-Cov-2 virus and the immunity-induced pathology related to COVID-19 and determine how this impinges on the use of current disease modifying treatments in multiple sclerosis. OBSERVATIONS: : Although information about the mechanisms of immunity are scant, it appears that monocyte/macrophages and then CD8 T cells are important in eliminating the SARS-CoV-2 virus. This may be facilitated via anti-viral antibody responses that may prevent re-infection. However, viral escape and infection of leucocytes to promote lymphopenia, apparent CD8 T cell exhaustion coupled with a cytokine storm appears to contribute to the damage in ARDS. IMPLICATIONS: : In contrast to ablative haematopoietic stem cell therapy, most multiple-sclerosis-related disease modifying therapies do not particularly target the innate immune system and few have any major long-term impact on CD8 T cells to limit protection against COVID-19. In addition, few block the formation of immature B cells within lymphoid tissue that will provide antibody-mediated protection from (re)infection. However, adjustments to dosing schedules may help de-risk the chance of infection further and reduce the concerns of people with MS being treated during the COVID-19 pandemic.

negative: COVID-19–We urgently need to start developing an exit strategy Abstract Aim The purpose of this perspective is to review the options countries have to exit the draconian “lock downs” in a carefully staged manner. Methods Experts from different countries experiencing Corona Virus Infectious Disease 2019 (COVID-19) review evidence and country specific approaches and results of their interventions. Results Three key factors are important: 1. Reintroduction from countries with ongoing community transmission; 2. The need for extensive testing capacity and widespread community testing, and 3. Adequate supply of personal protective equipment, PPE, to protect health care workers. Lifting social distancing is discussed at length. How to open manufacturing, construction and logistics. The opening og higher educational institutions and schools. The use of electronic surveillance is discussed. Conclusion Each country has to decide what is the best path forward. However, we can learn from each other and the approach is in reality very similar.

negative: Estimation of SARS-CoV-2 mortality during the early stages of an epidemic: a modelling study in Hubei, China and northern Italy Background. The epidemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that originated in Wuhan, China in late 2019 is now pandemic. Reliable estimates of death from coronavirus disease 2019 (COVID-19) are essential to guide control efforts and to plan health care system requirements. The objectives of this study are to: 1) simulate the transmission dynamics of SARS-CoV-2 using publicly available surveillance data; 2) give estimates of SARS-CoV-2 mortality adjusted for bias in the two regions with the world's highest numbers of confirmed Covid-19 deaths: Hubei province, China and northern Italy. Method and Findings. We developed an age-stratified susceptible-exposed-infected-removed (SEIR) compartmental model describing the dynamics of transmission and mortality during the SARS-CoV-2 epidemic. Our model accounts for two biases; preferential ascertainment of severe cases and delayed mortality (right-censoring). We fitted our transmission model to surveillance data from Hubei province (1 January to 11 February 2020) and northern Italy (8 February to 3 March 2020). Overall mortality among all symptomatic and asymptomatic infections was estimated to be 3.0% (95% credible interval: 2.6-3.4%) in Hubei province and 3.3% (2.0-4.7%) in northern Italy. Mortality increased with age; we estimate that among 80+ year olds, 39.0% (95%CrI: 31.1-48.9%) in Hubei province and 89.0% (95%CrI: 56.2-99.6%) in northern Italy dies or will die. Limitations are that the model requires data recorded by date of onset and that sex-disaggregated mortality was not available. Conclusions. We developed a mechanistic approach to correct the crude CFR for bias due to right-censoring and preferential ascertainment and provide adjusted estimates of mortality due to SARS-CoV-2 infection by age group. While specific to the situation in Hubei, China and northern Italy during these periods, these findings will help the mitigation efforts and planning of resources as other regions prepare for SARS-CoV-2 epidemics.

negative: SARS-CoV-2 and viral sepsis: observations and hypotheses Summary Since the outbreak of coronavirus disease 2019 (COVID-19), clinicians have tried every effort to understand the disease, and a brief portrait of its clinical features have been identified. In clinical practice, we noticed that many severe or critically ill COVID-19 patients developed typical clinical manifestations of shock, including cold extremities and weak peripheral pulses, even in the absence of overt hypotension. Understanding the mechanism of viral sepsis in COVID-19 is warranted for exploring better clinical care for these patients. With evidence collected from autopsy studies on COVID-19 and basic science research on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and SARS-CoV, we have put forward several hypotheses about SARS-CoV-2 pathogenesis after multiple rounds of discussion among basic science researchers, pathologists, and clinicians working on COVID-19. We hypothesise that a process called viral sepsis is crucial to the disease mechanism of COVID-19. Although these ideas might be proven imperfect or even wrong later, we believe they can provide inputs and guide directions for basic research at this moment.

negative: Late onset, symptomatic, demyelinating encephalomyelitis in mice infected with MHV-JHM in the presence of maternal antibody Abstract The presence of maternal antibodies protected suckling C57BL/6 mice from the clinical manifestations of the acute encephalomyelitis caused by mouse hepatitis virus, strain JHM (MHV-JHM), a coronavirus, even though histological evidence of encephalomyelitis was found at early times after inoculation. 100% of infected suckling mice developed a fatal disease in the absence of maternal antibody. By 14 days after inoculation, the brains of all antibody-protected mice examined were nearly normal on histological examination. At 3–8 weeks post-inoculation, approximately 40% of the antibody-protected mice developed a neurological disease characterized by hindlimb paralysis and wasting. Evidence of inflammation and demyelination was apparent in the spinal cord and brainstem. The mice that remained asymptomatic at this time showed few signs of inflammation and none developed clinical disease over the following 9 months. Viral antigen could be detected in most of the mice examined at all times after inoculation, whether symptomatic or not, and was particularly evident in the animals with hindlimb paralysis. MHV-JHM could be consistently cultured from the mice with hindlimb paralysis. These results show that maternal immune factors can completely protect susceptible mice from the acute, fatal, clinical encephalomyelitis caused by MHV-JHM, but cannot prevent the establishment of a latent state and subsequent development of virus-induced, clinically evident, demyelinating disease. This model will be useful for studying the virus and host factors important for the development of MHV-JHM latency and subsequent virus-induced demyelination.

negative: What We Know So Far (As of March 26, 2020) About COVID-19 – An MRT Point of View

negative: Infection and cross-protection studies of winter dysentery and calf diarrhea bovine coronavirus strains in colostrum-deprived and gnotobiotic calves. OBJECTIVE To investigate in vitro antigenic relations, in vivo cross-protection, and isotype antibody responses to a winter dysentery (WD) and calf diarrhea strain of bovine coronavirus (BCV). DESIGN AND ANIMALS: Gnotobiotic and colostrum-deprived calves were inoculated oronasally with a WD (DBA) or a calf diarrhea (DB2) BCV, and were challenge exposed with the heterologous BCV. PROCEDURE Nasal swab and feces specimens and blood samples were collected. Fecal and nasal specimens were assayed for BCV shedding by antigen-capture ELISA or immune electron microscopy. Bovine coronavirus antigens were detected in nasal epithelial cells by immunofluorescence. Antibody titers to BCV in serum were assayed by virus neutralization (VN), and BCV antibody isotype titers in feces and sera were quantitated by ELISA. RESULTS All calves developed diarrhea and shed BCV nasally and in feces, then recovered and were protected from BCV-associated diarrhea after challenge exposure with the heterologous BCV. After challenge exposure with either strain, fecal shedding of DBA was detected in 1 of 4 calves and nasal shedding of DB2 was detected in 2 of 4 calves. Immunoglobulin M was the principal coproantibody to BCV early, followed predominantly by IgA. Immunoglobulin G1 coproantibody titers to BCV were low, but increased after challenge exposure. Immunoglobulin G1 antibodies were predominant in serum. After challenge exposure, all serum antibody isotype titers increased except IgG2. The VN antibody responses paralleled serum IgG1 antibody responses. CONCLUSIONS AND CLINICAL RELEVANCE Immunoglobulin A coproantibodies at challenge exposure were associated with protection against diarrhea. Nasal shedding of BCV after challenge exposure confirmed field data documenting reinfection of the respiratory tract of cattle, suggesting that, in closed herds, respiratory tract infections constitute a source of BCV transmission to cows (WD) or young calves.

negative: A study of non-prescription usage of antibiotics in the upper respiratory tract infections in the urban population

negative: Virtual screening-driven drug discovery of SARS-CoV2 enzyme inhibitors targeting viral attachment, replication, post-translational modification and host immunity evasion infection mechanisms The novel coronavirus SARS-CoV2, the causative agent of the pandemic disease COVID-19, emerged in December 2019 forcing lockdown of communities in many countries. The absence of specific drugs and vaccines, the rapid transmission of the virus, and the increasing number of deaths worldwide necessitated the discovery of new substances for anti-COVID-19 drug development. With the aid of bioinformatics and computational modelling, ninety seven antiviral secondary metabolites from fungi were docked onto five SARS-CoV2 enzymes involved in viral attachment, replication, post-translational modification, and host immunity evasion infection mechanisms followed by molecular dynamics simulation and in silico ADMET prediction (absorption, distribution, metabolism, excretion and toxicity) of the hit compounds. Thus, three fumiquinazoline alkaloids scedapin C (15), quinadoline B (19) and norquinadoline A (20), the polyketide isochaetochromin D1 (8), and the terpenoid 11a-dehydroxyisoterreulactone A (11) exhibited high binding affinities on the target proteins, papain-like protease (PLpro), chymotrypsin-like protease (3CLpro), RNA-directed RNA polymerase (RdRp), non-structural protein 15 (nsp15), and the spike binding domain to GRP78. Molecular dynamics simulation was performed to optimize the interaction and investigate the stability of the top-scoring ligands in complex with the five target proteins. All tested complexes were found to have dynamic stability. Of the five top-scoring metabolites, quinadoline B (19) was predicted to confer favorable ADMET values, high gastrointestinal absorptive probability and poor blood-brain barrier crossing capacities. Communicated by Ramaswamy H. Sarma

negative: Factors influencing Dipylidium sp. infection in a free-ranging social carnivore, the spotted hyaena (Crocuta crocuta)() We provide the first genetic sequence data for a Dipylidium species from a wild carnivore plus an analysis of the effects of ecological, demographic, physiological and behavioural factors on Dipylidium sp. infection prevalence in a social carnivore, the spotted hyaena (Crocuta crocuta), in the Serengeti National Park, Tanzania. Our sequence data from a mitochondrial gene fragment (1176 base pair long) had a similarity of between 99% and 89% to Dipylidium caninum. We determined infection prevalence in 146 faecal samples from 124 known animals in three social groups (termed clans) using molecular screening and Dipylidium proglottid presence. Our analysis revealed significantly higher infection prevalence in juveniles (55%) than adults (15.8%), indicating that predominantly juveniles maintained infection in clans. The likelihood of infection in juveniles significantly: (1) increased as the number of adults and older juveniles (>6 months) at communal dens increased, implying a positive relationship between this factor and the size of the intermediate host (probably a flea species) population at communal dens; (2) decreased as the number of younger juveniles (<6 months) increased, suggesting that the chance of susceptible juveniles ingesting infected fleas during self-grooming declined as the number of infected fleas per younger juvenile declined; and (3) decreased during periods of low prey abundance in clan territories when an increased reliance on long-distances foraging excursions reduces the number of clan members visiting communal dens, possibly resulting in a decline in flea populations at dens. Long-distance foraging also increases the intervals (in days) between nursing visits by lactating females to their offspring. Lengthy intervals between milk intake by infected juveniles may reduce adult Dipylidium fecundity and hence decrease infection prevalence in the den flea population. Our study provides useful insights into Dipylidium epidemiology in a social carnivore population subject to large fluctuations in prey abundance.

negative: Acceptance and preference for COVID-19 vaccination in health-care workers (HCWs) The objective of the present study is to reveal the acceptance and preference for the 2019 novel coronavirus disease (COVID-19) vaccination in health-care workers (HCWs). We performed an internet-based, region-stratified survey among 352 HCWs and 189 individuals in the general population enrolled on March 17th and 18th 2020 from 26 Chinese provinces. The HCWs developed a more in-depth understanding of SARS-Coronavirus-2 infection and showed a higher tolerance to the future vaccination than the general population. 76.4% of HCWs (vs. 72.5% in the general) showed their willingness to receive vaccination. Potential benefits from COVID-19 outbreak such as seeking influenza (65.3%) or pneumonia (55.7%) vaccination can be gained in HCWs. To estimate the relative effects of attributes influencing vaccination choice in the discrete choice experiment, 7 attributes (3 disease-relevant, 3 vaccine-relevant, and 1 of social acceptance) were identified as key determinants. Among them, disease trend (odds ratio, OR: 4.367 (95%CI, 3.721-5.126) for seasonal epidemic, OR: 3.069 (2.612-3.605) for persistent epidemic, with reference to disappearance in summer), social contacts decisions (0.398: 0.339-0.467 for refusal, 0.414: 0.353-0.487 for neutral, with reference to acceptance) and high possibility of being infected (2.076: 1.776-2.425 for infection probability of 30%+ ) were significantly associated with increased probability of choosing vaccination in the HCWs. In contrast, for the general population, vaccine safety and social contacts decisions were the most important predictors. For COVID-19 vaccination, education in HCWs should be taken as a priority, and further benefits of its recommendation to the general public will also be anticipated.

negative: SARS-CoV-2 COVID-19 susceptibility and lung inflammatory storm by smoking and vaping The current pandemic of COVID-19 has caused severe morbidity and mortality across the globe. People with a smoking history have severe disease outcomes by COVID-19 infection. Epidemiological studies show that old age and pre-existing disease conditions (hypertension and diabetes) result in severe disease outcome and mortality amongst COVID-19 patients. Evidences suggest that the S1 domain of the SARS-CoV-2 (causative agent of COVID-19) membrane spike has a high affinity towards the angiotensin-converting enzyme 2 (ACE2) receptor found on the host’s lung epithelium. Likewise, TMPRSS2 protease has been shown to be crucial for viral activation thus facilitating the viral engulfment. The viral entry has been shown to cause ‘cytokine storm’ involving excessive production of pro-inflammatory cytokines/chemokines including IL-6, TNF-α, IFN-γ, IL-2, IL-7, IP-10, MCP-3 or GM-CSF, which is augmented by smoking. Future research could target these inflammatory-immunological responses to develop effective therapy for COVID-19. This mini-review provides a consolidated account on the role of inflammation and immune responses, proteases, and epithelial permeability by smoking and vaping during SARS-CoV2 infection with future directions of research, and provides a list of the potential targets for therapies particularly controlling cytokine storms in the lung.

negative: Induction of protective immunity against severe acute respiratory syndrome coronavirus (SARS-CoV) infection using highly attenuated recombinant vaccinia virus DIs Abstract SARS-coronavirus (SARS-CoV) has recently been identified as the causative agent of SARS. We constructed a series of recombinant DIs (rDIs), a highly attenuated vaccinia strain, expressing a gene encoding four structural proteins (E, M, N and S) of SARS-CoV individually or simultaneously. These rDIs elicited SARS-CoV-specific serum IgG antibody and T-cell responses in vaccinated mice following intranasal or subcutaneous administration. Mice that were subcutaneously vaccinated with rDIs expressing S protein with or without other structural proteins induced a high level of serum neutralizing IgG antibodies and demonstrated marked protective immunity against SARS-CoV challenge in the absence of a mucosal IgA response. These results indicate that the potent immune response elicited by subcutaneous injection of rDIs containing S is able to control mucosal infection by SARS-CoV. Thus, replication-deficient DIs constructs hold promise for the development of a safe and potent SARS vaccine.

negative: Development of an inactivated vaccine candidate, BBIBP-CorV, with potent protection against SARS-CoV-2 Summary The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) threatens global public health. The development of a vaccine is urgently needed for the prevention and control of COVID-19. Here, we report the pilot-scale production of an inactivated SARS-CoV-2 vaccine candidate (BBIBP-CorV) that induces high levels of neutralizing antibodies titers in mice, rats, guinea pigs, rabbits and nonhuman primates (cynomolgus monkeys and rhesus macaques) to provide protection against SARS-CoV-2. Two-dose immunizations using 2 μg/dose of BBIBP-CorV provided highly efficient protection against SARS-CoV-2 intratracheal challenge in rhesus macaques, without detectable antibody-dependent enhancement of infection. In addition, BBIBP-CorV exhibits efficient productivity and good genetic stability for vaccine manufacture. These results support the further evaluation of BBIBP-CorV in a clinical trial.

negative: Features, Evaluation and Treatment Coronavirus (COVID-19) According to the World Health Organization (WHO), viral diseases continue to emerge and represent a serious issue to public health In the last twenty years, several viral epidemics such as the severe acute respiratory syndrome coronavirus (SARS-CoV) in 2002 to 2003, and H1N1 influenza in 2009, have been recorded Most recently, the Middle East respiratory syndrome coronavirus (MERS-CoV) was first identified in Saudi Arabia in 2012 In a timeline that reaches the present day, an epidemic of cases with unexplained low respiratory infections detected in Wuhan, the largest metropolitan area in China's Hubei province, was first reported to the WHO Country Office in China, on December 31, 2019 Published literature can trace the beginning of symptomatic individuals back to the beginning of December 2019 As they were unable to identify the causative agent, these first cases were classified as "pneumonia of unknown etiology " The Chinese Center for Disease Control and Prevention (CDC) and local CDCs organized an intensive outbreak investigation program The etiology of this illness is now attributed to a novel virus belonging to the coronavirus (CoV) family, COVID-19 On February 11, 2020, the WHO Director-General, Dr Tedros Adhanom Ghebreyesus, announced that the disease caused by this new CoV was a "COVID-19," which is the acronym of "coronavirus disease 2019" In the past twenty years, two additional coronavirus epidemics have occurred SARS-CoV provoked a large-scale epidemic beginning in China and involving two dozen countries with approximately 8000 cases and 800 deaths, and the MERS-CoV that began in Saudi Arabia and has approximately 2,500 cases and 800 deaths and still causes as sporadic cases This new virus seems to be very contagious and has quickly spread globally In a meeting on January 30, 2020, per the International Health Regulations (IHR, 2005), the outbreak was declared by the WHO a Public Health Emergency of International Concern (PHEIC) as it had spread to 18 countries with four countries reporting human-to-human transmission An additional landmark occurred on February 26, 2020, as the first case of the disease, not imported from China, was recorded in the United States Initially, the new virus was called 2019-nCoV Subsequently, the task of experts of the International Committee on Taxonomy of Viruses (ICTV) termed it the SARS-CoV-2 virus as it is very similar to the one that caused the SARS outbreak (SARS-CoVs) The CoVs have become the major pathogens of emerging respiratory disease outbreaks They are a large family of single-stranded RNA viruses (+ssRNA) that can be isolated in different animal species For reasons yet to be explained, these viruses can cross species barriers and can cause, in humans, illness ranging from the common cold to more severe diseases such as MERS and SARS Interestingly, these latter viruses have probably originated from bats and then moving into other mammalian hosts — the Himalayan palm civet for SARS-CoV, and the dromedary camel for MERS-CoV — before jumping to humans The dynamics of SARS-Cov-2 are currently unknown, but there is speculation that it also has an animal origin The potential for these viruses to grow to become a pandemic worldwide seems to be a serious public health risk Concerning COVID-19, the WHO raised the threat to the CoV epidemic to the "very high" level, on February 28, 2020 Probably, the effects of the epidemic caused by the new CoV has yet to emerge as the situation is quickly evolving World governments are at work to establish countermeasures to stem possible devastating effects Health organizations coordinate information flows and issues directives and guidelines to best mitigate the impact of the threat At the same time, scientists around the world work tirelessly, and information about the transmission mechanisms, the clinical spectrum of disease, new diagnostics, and prevention and therapeutic strategies are rapidly developing Many uncertainties remain with regard to both the virus-host interac ion and the evolution of the epidemic, with specific reference to the times when the epidemic will reach its peak At the moment, the therapeutic strategies to deal with the infection are only supportive, and prevention aimed at reducing transmission in the community is our best weapon Aggressive isolation measures in China have led to a progressive reduction of cases in the last few days In Italy, in geographic regions of the north of the peninsula, political and health authorities are making incredible efforts to contain a shock wave that is severely testing the health system In the midst of the crisis, the authors have chosen to use the "Statpearls" platform because, within the PubMed scenario, it represents a unique tool that may allow them to make updates in real-time The aim, therefore, is to collect information and scientific evidence and to provide an overview of the topic that will be continuously updated

negative: Heterosubtypic Protections against Human-Infecting Avian Influenza Viruses Correlate to Biased Cross-T-Cell Responses Against a backdrop of seasonal influenza virus epidemics, emerging avian influenza viruses (AIVs) occasionally jump from birds to humans, posing a public health risk, especially with the recent sharp increase in H7N9 infections. Evaluations of cross-reactive T-cell immunity to seasonal influenza viruses and human-infecting AIVs have been reported previously. However, the roles of influenza A virus-derived epitopes in the cross-reactive T-cell responses and heterosubtypic protections are not well understood; understanding those roles is important for preventing and controlling new emerging AIVs. Here, among the members of a healthy population presumed to have previously been infected by pandemic H1N1 (pH1N1), we found that pH1N1-specific T cells showed cross- but biased reactivity to human-infecting AIVs, i.e., H5N1, H6N1, H7N9, and H9N2, which correlates with distinct protections. Through a T-cell epitope-based phylogenetic analysis, the cellular immunogenic clustering expanded the relevant conclusions to a broader range of virus strains. We defined the potential key conserved epitopes required for cross-protection and revealed the molecular basis for the immunogenic variations. Our study elucidated an overall profile of cross-reactivity to AIVs and provided useful recommendations for broad-spectrum vaccine development.

negative: Recombinant Chimpanzee Adenovirus Vaccine AdC7-M/E Protects against Zika Virus Infection and Testis Damage. The recent outbreak of Zika virus (ZIKV) has emerged as a global health concern. ZIKV can persist in human semen and be transmitted by sexual contact, as well as by mosquitoes, as seen for classical arboviruses. We along with others have previously demonstrated that ZIKV infection leads to testis damage and infertility in mouse models. So far, no prophylactics or therapeutics are available; therefore, vaccine development is urgently demanded. Recombinant chimpanzee adenovirus has been explored as the preferred vaccine vector for many pathogens due to the low preexisting immunity against the vector among the human population. Here, we developed a ZIKV vaccine based on recombinant chimpanzee adenovirus type 7 (AdC7) expressing ZIKV M/E glycoproteins. A single vaccination of AdC7-M/E was sufficient to elicit potent neutralizing antibodies and protective immunity against ZIKV in both immunocompetent and immunodeficient mice. Moreover, vaccinated mice rapidly developed neutralizing antibody with high titers within 1 week postvaccination, and the elicited antiserum could cross-neutralize heterologous ZIKV strains. Additionally, ZIKV M- and E-specific T cell responses were robustly induced by AdC7-M/E. Moreover, one-dose inoculation of AdC7-M/E conferred mouse sterilizing immunity to eliminate viremia and viral burden in tissues against ZIKV challenge. Further investigations showed that vaccination with AdC7-M/E completely protected against ZIKV-induced testicular damage. These data demonstrate that AdC7-M/E is highly effective and represents a promising vaccine candidate for ZIKV control.IMPORTANCE Zika virus (ZIKV) is a pathogenic flavivirus that causes severe clinical consequences, including congenital malformations in fetuses and Guillain-Barré syndrome in adults. Vaccine development is a high priority for ZIKV control. In this study, to avoid preexisting anti-vector immunity in humans, a rare serotype chimpanzee adenovirus (AdC7) expressing the ZIKV M/E glycoproteins was used for ZIKV vaccine development. Impressively, AdC7-M/E exhibited exceptional performance as a ZIKV vaccine, as follows: (i) protective efficacy by a single vaccination, (ii) rapid development of a robust humoral response, (iii) durable immune responses, (iv) robust T cell responses, and (v) sterilizing immunity achieved by a single vaccination. These advantages of AdC7-M/E strongly support its potential application as a promising ZIKV vaccine in the clinic.

negative: Viral syndromes This chapter focuses on several viral syndromes. The impression that viral infections dominate is strengthened if the abundance of subclinical virus infections is considered, in particular those in children. The most serious medical consequences of viral pneumonia are encountered in the old, the newborn, or the patient with a circulatory or respiratory handicap. Influenza is a cause of increased mortality among the old, while RS virus is the most important respiratory virus infection in small children. Fever and a reddened sore throat are among the most common symptoms of infection, and are seen in association with many virus infections. The predominant number of cases of pharyngitis in children and young adults are because of virus infections. Rotavirus is recognized by its characteristic double-layered capsid with cubical symmetry and by its size, 70 nm in diameter. There are rotaviruses of many different animal species, and some have antigenic and biological properties in common with the three human serotypes.

negative: Unprecedented nationwide blood studies seek to track U.S. coronavirus spread We still don’t know how many people have been infected with the novel coronavirus, SARS-CoV-2 Not only have countries struggled to roll out wide-scale testing for the virus, those efforts inevitably will miss people who have recovered from an infection The best way to figure out how far and wide the virus has spread in a population is to look at blood Antibodies, blood proteins that the immune system produces to attack pathogens, are viral fingerprints that remain long after infections are cleared Sensitive tests can detect them even in people who never felt a single symptom of COVID-19 The World Health Organization has announced an ambitious global effort, called Solidarity II, of so-called serosurveys, studies that look for antibodies to SARS-CoV-2 in the population

negative: Immune responses in Balb/c mice induced by a candidate SARS-CoV inactivated vaccine prepared from F69 strain The immunogenicity of a candidate-inactivated vaccine prepared from SARS-CoV F69 strain was evaluated in Balb/c mice. Potent humoral immune responses were induced under the elicitation of three times of immunizations at 2-week intervals with this vaccine, combined with three types of adjuvants (Freund's adjuvant, Al(OH)(3) adjuvant and CpG adjuvant). Titers of specific IgG antibodies in three test groups all peaked in the sixth week after first vaccination, but significant differences existed in the kinetics of specific IgG antibody levels. The strong neutralizing capacity exhibited in micro-cytopathic effect neutralization tests indicated the specific antibodies are protective. Western blot assay further demonstrated the specificity of the induced serum antibodies.

negative: Immunoreactivity characterisation of the three structural regions of the human coronavirus OC43 nucleocapsid protein by Western blot: Implications for the diagnosis of coronavirus infection Abstract Previous studies have reported that a prokaryotic-expressed recombinant nucleocapsid protein (NP) is a suitable reagent for the epidemiological screening of coronavirus infection. In this study, soluble recombinant human coronavirus OC43 (HCoV-OC43) NP was produced to examine the antigenicity of the HCoV-OC43 NP of betacoronavirus. Using the purified recombinant NP as an antigen, a polyclonal antibody from rabbit serum with specificity for HCoV-OC43 NP was generated; this antibody reacts specifically with HCoV-OC43 NP and does not cross-react with other human CoV NPs (including those of SARS-CoV and HCoV-229E) by Western blot. Sera from 26 young adults, 17 middle-aged and elderly patients with respiratory infection, and 15 cord blood samples were also tested. Strong reactivity to the NPs of HCoV-OC43 was observed in 96%, 82%, and 93% of the serum samples from the young adults, respiratory patients, and cord blood samples, respectively. To identify the immunoreactivities of the three structural regions of the NP that are recognised by the rabbit polyclonal antibody and human serum, the antigenicities of three protein fragments, including the N-terminal domain (aa 1-173), the central-linker region (aa 174-300), and the C-terminal domain (aa 301-448), were evaluated by Western blot. The rabbit polyclonal antibody demonstrated greater immunoreactivity to the central-linker region and the C-terminal domain than to the N-terminal domain. Three different patterns for the immunoreactivities of the three structural regions of HCoV-OC43 NP were observed in human serum, suggesting variability in the immune responses that occur during HCoV-OC43 infection in humans. The central-linker region of the NP appeared to be the most highly immunoreactive region for all three patterns observed. The goal of this study was to offer insight into the design of diagnostic tools for HCoV infection.

negative: Coronavirus avian infectious bronchitis virus. Infectious bronchitis virus (IBV), the coronavirus of the chicken (Gallus gallus), is one of the foremost causes of economic loss within the poultry industry, affecting the performance of both meat-type and egg-laying birds. The virus replicates not only in the epithelium of upper and lower respiratory tract tissues, but also in many tissues along the alimentary tract and elsewhere e.g. kidney, oviduct and testes. It can be detected in both respiratory and faecal material. There is increasing evidence that IBV can infect species of bird other than the chicken. Interestingly breeds of chicken vary with respect to the severity of infection with IBV, which may be related to the immune response. Probably the major reason for the high profile of IBV is the existence of a very large number of serotypes. Both live and inactivated IB vaccines are used extensively, the latter requiring priming by the former. Their effectiveness is diminished by poor cross-protection. The nature of the protective immune response to IBV is poorly understood. What is known is that the surface spike protein, indeed the amino-terminal S1 half, is sufficient to induce good protective immunity. There is increasing evidence that only a few amino acid differences amongst S proteins are sufficient to have a detrimental impact on cross-protection. Experimental vector IB vaccines and genetically manipulated IBVs--with heterologous spike protein genes--have produced promising results, including in the context of in ovo vaccination.

negative: Protease inhibitors broadly effective against feline, ferret and mink coronaviruses Abstract Ferret and mink coronaviruses typically cause catarrhal diarrhea in ferrets and minks, respectively. In recent years, however, systemic fatal coronavirus infection has emerged in ferrets, which resembles feline infectious peritonitis (FIP) in cats. FIP is a highly fatal systemic disease caused by a virulent feline coronavirus infection in cats. Despite the importance of coronavirus infections in these animals, there are no effective commercial vaccines or antiviral drugs available for these infections. We have previously reported the efficacy of a protease inhibitor in cats with FIP, demonstrating that a virally encoded 3C-like protease (3CLpro) is a valid target for antiviral drug development for coronavirus infections. In this study, we extended our previous work on coronavirus inhibitors and investigated the structure-activity relationships of a focused library of protease inhibitors for ferret and mink 3CLpro. Using the fluorescence resonance energy transfer assay, we identified potent inhibitors broadly effective against feline, ferret and mink coronavirus 3CLpro. Multiple amino acid sequence analysis and modelling of 3CLpro of ferret and mink coronaviruses were conducted to probe the structural basis for these findings. The results of this study provide support for further research to develop broad-spectrum antiviral agents for multiple coronavirus infections. To the best of our knowledge, this is the first report on small molecule inhibitors of ferret and mink coronaviruses.

negative: Microscopic Review of Nasopharyngeal Swabs as a Means of Benchside Quality Assurance Nasopharygneal swabs (NPS) are the collection modality recommended by the Centers for Disease Control and Prevention (CDC) for reverse-transcription polymerase chain reaction (RT-PCR) testing for SARS-CoV2. NPS gather both extracellular material and human respiratory epithelial cells and, when used with RT-PCR, have reliable sensitivity for detection of viral infection. However, at our institution, we identified a 1.7% re-order rate within 7-days for NPS for respiratory pathogen RT-PCR, which we hypothesize may be due to low confidence in adequate sample collection. We sought to identify an inexpensive and accessible strategy for benchside quality assurance of NPS adequacy by observing microscopic content of viral transport media. For 801 NPS samples collected in November 2019, we air-dried and safranin-stained aliquots of viral transport media on glass slides. We then counted morphologically distinct ciliated columnar epithelial cells (CCEs). 19% of samples negative by RT-PCR for respiratory pathogens had no CCEs, while just 6% of positive samples exhibited the same. Pearson's Chi-squared test was used to compare presence of CCEs between samples that were positive and negative for respiratory pathogens by RT-PCR (p=3.3x10-38). The negative predictive value (NPV) of finding no identifiable CCEs on microscopy was 85%. We posit that samples without identifiable CCEs may have been inadequately collected. The basic, benchside protocol using inexpensive laboratory reagents that we describe here could help improve accuracy and accessibility of NPS and RT-PCR testing for SARS-CoV2 and other respiratory pathogens while conserving limited resources in the face of a pandemic.

negative: Improved Molecular Diagnosis of COVID-19 by the Novel, Highly Sensitive and Specific COVID-19-RdRp/Hel Real-Time Reverse Transcription-PCR Assay Validated In Vitro and with Clinical Specimens On 31 December 2019, the World Health Organization was informed of a cluster of cases of pneumonia of unknown etiology in Wuhan, China. Subsequent investigations identified a novel coronavirus, now named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), from the affected patients. Highly sensitive and specific laboratory diagnostics are important for controlling the rapidly evolving SARS-CoV-2-associated coronavirus disease 2019 (COVID-19) epidemic. In this study, we developed and compared the performance of three novel real-time reverse transcription-PCR (RT-PCR) assays targeting the RNA-dependent RNA polymerase (RdRp)/helicase (Hel), spike (S), and nucleocapsid (N) genes of SARS-CoV-2 with that of the reported RdRp-P2 assay, which is used in >30 European laboratories. Among the three novel assays, the COVID-19-RdRp/Hel assay had the lowest limit of detection in vitro (1.8 50% tissue culture infective doses [TCID(50)]/ml with genomic RNA and 11.2 RNA copies/reaction with in vitro RNA transcripts). Among 273 specimens from 15 patients with laboratory-confirmed COVID-19 in Hong Kong, 77 (28.2%) were positive by both the COVID-19-RdRp/Hel and RdRp-P2 assays. The COVID-19-RdRp/Hel assay was positive for an additional 42 RdRp-P2-negative specimens (119/273 [43.6%] versus 77/273 [28.2%]; P < 0.001), including 29/120 (24.2%) respiratory tract specimens and 13/153 (8.5%) non-respiratory tract specimens. The mean viral load of these specimens was 3.21 × 10(4) RNA copies/ml (range, 2.21 × 10(2) to 4.71 × 10(5) RNA copies/ml). The COVID-19-RdRp/Hel assay did not cross-react with other human-pathogenic coronaviruses and respiratory pathogens in cell culture and clinical specimens, whereas the RdRp-P2 assay cross-reacted with SARS-CoV in cell culture. The highly sensitive and specific COVID-19-RdRp/Hel assay may help to improve the laboratory diagnosis of COVID-19.

negative: Humoral innate immune response and disease The humoral innate immune response consists of multiple components, including the naturally occurring antibodies (NAb), pentraxins and the complement and contact cascades. As soluble, plasma components, these innate proteins provide key elements in the prevention and control of disease. However, pathogens and cells with altered self proteins utilize multiple humoral components to evade destruction and promote pathogy. Many studies have examined the relationship between humoral immunity and autoimmune disorders. This review focuses on the interactions between the humoral components and their role in promoting the pathogenesis of bacterial and viral infections and chronic diseases such as atherosclerosis and cancer. Understanding the beneficial and detrimental aspects of the individual components and the interactions between proteins which regulate the innate and adaptive response will provide therapeutic targets for subsequent studies.

negative: Guidelines for the management of surgical departments in non-uniform hospitals during the COVID-19 pandemic In the last several weeks we have been witnessing the exponentially progressing pandemic SARS-CoV-2 coronavirus. As the number of people infected with SARS-CoV2 escalates, the problem of surgical management of patients requiring urgent surgery is increasing. Patients infected with SARS-CoV2 virus but with negative test results will appear in general hospitals and may pose a risk to other patients and hospital staff. Health care workers constitutes nearly 17% of infected population in Poland, therefore early identification of infected people becomes a priority to protect human resources and to ensure continuity of the access to a surgical care. Both surgical operations, and endoscopic procedures are considered as interventions with an increased risk of infection. Therefore, determining the algorithm becomes crucial for qualifying patients for surgical treatment, but also to stratify the risk of personnel being infected during surgery and to adequately protect staff. Each hospital should be logistically prepared for the need to perform urgent surgery on a patient with suspected or confirmed infection, including personal protective equipment. Limited availability of the equipment, working under pressure and staff shortages in addition to a highly contagious pathogen necessitate a pragmatic management of human resources in health care. Instant synchronized action is needed, and clear uniform guidelines are essential for the healthcare system to provide citizens with the necessary surgical care while protecting both patients, and staff. This document presents current recommendations regarding surgery during the COVID-19 pandemic in Poland.

negative: Recommendations for coronavirus infection in rheumatic diseases treated with biologic therapy Abstract The Coronavirus-associated disease, that was first identified in 2019 in China (CoViD-19), is a pandemic caused by a bat-derived beta-coronavirus, named SARS-CoV2. It shares homology with SARS and MERS-CoV, responsible for past outbreaks in China and in Middle East. SARS-CoV2 spread from China where the first infections were described in December 2019 and is responsible for the respiratory symptoms that can lead to acute respiratory distress syndrome. A cytokine storm has been shown in patients who develop fatal complications, as observed in past coronavirus infections. The management includes ventilatory support and broad-spectrum antiviral drugs, empirically utilized, as a targeted therapy and vaccines have not been developed. Based upon our limited knowledge on the pathogenesis of CoViD-19, a potential role of some anti-rheumatic drugs may be hypothesized, acting as direct antivirals or targeting host immune response. Antimalarial drugs, commonly used in rheumatology, may alter the lysosomal proteases that mediates the viral entry into the cell and have demonstrated efficacy in improving the infection. Anti-IL-1 and anti-IL-6 may interfere with the cytokine storm in severe cases and use of tocilizumab has shown good outcomes in a small cohort. Baricitinib has both antiviral and anti-inflammatory properties. Checkpoints inhibitors such as anti-CD200 and anti-PD1 could have a role in the treatment of CoViD-19. Rheumatic disease patients taking immunosuppressive drugs should be recommended to maintain the chronic therapy, prevent infection by avoiding social contacts and pausing immunosuppressants in case of infection. National and international registries are being created to collect data on rheumatic patients with CoViD-19.

negative: Causes of hypogeusia/hyposmia in SARS-CoV2 infected patients

negative: Potential adjuvants for the development of a SARS-CoV-2 vaccine based on experimental results from similar coronaviruses The extensive efforts around the globe are being made to develop a suitable vaccine against COVID-19 (Coronavirus Disease-19) caused by SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus-2). An effective vaccine should be able to induce high titers of neutralizing antibodies to prevent the virus from attaching to the host cell receptors. However, to elicit the protective levels of antibodies, a vaccine may require multiple doses or assistance from other immunostimulatory molecules. Further, the vaccine should be able to induce protective levels of antibodies rapidly with the least amount of antigen used. This not only decreases the cost of a vaccine and make it affordable, but also reduces the quantity of the antigen used. As the pandemic has hit most countries across the globe, there will be an overwhelming demand for the vaccine in a quick time. Incorporating a suitable adjuvant in a SARS-CoV-2 vaccine may address these requirements. This review paper will discuss the experimental results of the adjuvanted vaccine studies with similar coronaviruses (CoVs) which might be useful to select an appropriate adjuvant for a vaccine against rapidly emerging SARS-CoV-2. We also discuss the current progress in the development of adjuvanted vaccines against the disease.

negative: Middle East Respiratory Syndrome – Wann daran denken? Im Juni 2012 wurde erstmals eine Infektion mit Middle East Respiratory Syndrome Coronavirus (MERS-CoV) in Saudi Arabien diagnostiziert. Seither zirkuliert das Virus weiterhin im Nahen Osten und verursacht dort immer wieder größere nosokomiale Ausbrüche. Auch nach Deutschland wurde das Virus bereits importiert. So stellt sich die Frage, wann man differenzialdiagnostisch an MERS-CoV denken sollte und welche Maßnahmen zu ergreifen sind.

negative: SARS-coronavirus replicates in mononuclear cells of peripheral blood (PBMCs) from SARS patients Abstract Background: The etiologic agent of severe acute respiratory syndrome (SARS) is a recently identified, positive single-stranded RNA (ssRNA) coronavirus (SARS-CoV). Little is known about the dynamic changes of the viral replicative form in SARS cases. Objectives: Evaluate whether SARS-CoV can infect and replicate in peripheral blood mononuclear cells (PBMCs) of infected persons and reveal any dynamic changes to the virus during the course of the disease. Study design: Peripheral blood mononuclear cells collected from SARS cases infected by the same infectious source were tested for both negative-stranded RNA (minus-RNA, “replicative intermediates”) and positive-stranded RNA (genomic RNA) of SARS-CoV during the course of hospitalization by reverse transcription-polymerase chain reaction (RT-PCR). Results: SARS-CoV minus-RNA was detected in PBMCs from SARS patients. The viral replicative forms in PBMCs were detectable during a period of 6 days post-onset of the disease, while the plus-RNA were detectable for a longer period (8–12 days post-onset). Conclusions: SARS-coronavirus can infect and replicate within PBMCs of SARS patients, but viral replication in PBMCs seems subject to self-limitation.

negative: Not all interventions are equal for the height of the second peak In this paper we conduct a simulation study of the spread of an epidemic like COVID-19 with temporary immunity on finite spatial and non-spatial network models. In particular, we assume that an epidemic spreads stochastically on a scale-free network and that each infected individual in the network gains a temporary immunity after its infectious period is over. After the temporary immunity period is over, the individual becomes susceptible to the virus again. When the underlying contact network is embedded in Euclidean geometry, we model three different intervention strategies that aim to control the spread of the epidemic: social distancing, restrictions on travel, and restrictions on maximal number of social contacts per node. Our first finding is that on a finite network, a long enough average immunity period leads to extinction of the pandemic after the first peak, analogous to the concept of"herd immunity". For each model, there is a critical average immunity length $L_c$ above which this happens. Our second finding is that all three interventions manage to flatten the first peak (the travel restrictions most efficiently), as well as decrease the critical immunity length $L_c$, but elongate the epidemic. However, when the average immunity length $L$ is shorter than $L_c$, the price for the flattened first peak is often a high second peak: for limiting the maximal number of contacts, the second peak can be as high as 1/3 of the first peak, and twice as high as it would be without intervention. Thirdly, interventions introduce oscillations into the system and the time to reach equilibrium is, for almost all scenarios, much longer. We conclude that network-based epidemic models can show a variety of behaviors that are not captured by the continuous compartmental models.

negative: Coronavirus disease 2019 (COVID‐19) outbreak: Could pigs be vectors for human infections?

negative: Immunogenicity of SARS-CoV: the Receptor-Binding Domain of S Protein is a Major Target of Neutralizing Antibodies

negative: Social distancing strategies for curbing the COVID-19 epidemic The SARS-CoV-2 pandemic is straining healthcare resources worldwide, prompting social distancing measures to reduce transmission intensity. The amount of social distancing needed to curb the SARS-CoV-2 epidemic in the context of seasonally varying transmission remains unclear. Using a mathematical model, we assessed that one-time interventions will be insufficient to maintain COVID-19 prevalence within the critical care capacity of the United States. Seasonal variation in transmission will facilitate epidemic control during the summer months but could lead to an intense resurgence in the autumn. Intermittent distancing measures can maintain control of the epidemic, but without other interventions, these measures may be necessary into 2022. Increasing critical care capacity could reduce the duration of the SARS-CoV-2 epidemic while ensuring that critically ill patients receive appropriate care.

negative: Molecular Detection of SARS-CoV-2 in Formalin Fixed Paraffin Embedded Specimens Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of human coronavirus disease 2019 (COVID-19), emerged in Wuhan, China in December 2019. The virus rapidly spread globally, resulting in a public-health crisis including more than one million cases and tens of thousands of deaths. Here, we describe the identification and evaluation of commercially available reagents and assays for the molecular detection of SARS-CoV-2 in infected formalin fixed paraffin embedded (FFPE) cell pellets. We identified a suitable rabbit polyclonal anti-SARS-CoV spike protein antibody and a mouse monoclonal anti-SARS-CoV nucleocapsid protein (NP) antibody for cross detection of the respective SARS-CoV-2 proteins by immunohistochemistry (IHC) and immunofluorescence assay (IFA). Next, we established RNAscope in situ hybridization (ISH) to detect SARS-CoV-2 RNA. Furthermore, we established a multiplex fluorescence ISH (mFISH) to detect positive-sense SARS-CoV-2 RNA and negative-sense SARS-CoV-2 RNA (a replicative intermediate indicating viral replication). Finally, we developed a dual staining assay using IHC and ISH to detect SARS-CoV-2 antigen and RNA in the same FFPE section. These reagents and assays will accelerate COVID-19 pathogenesis studies in humans and in COVID-19 animal models.

negative: CovProfile: profiling the viral genome and gene expressions of SARS-COV-2 The SARS-CoV-2 virus has infected more than one million people worldwide to date. Knowing its genome and gene expressions is essential to understand the virus’ mechanism. Here, we propose a computational tool CovProfile to detect the viral genomic variations as well as viral gene expressions from the sequences obtained from Nanopore devices. We applied CovProfile to 11 samples, each from a terminally ill patient, and discovered that all the patients are infected by multiple viral strains, which might affect the reliability of phylogenetic analysis. Moreover, the expression of viral genes ORF1ab gene, S gene, M gene, and N gene are high among most of the samples. While performing the tests, we noticed a consistent abundance of transcript segments of MUC5B, presumably from the host, across all the samples.

negative: Inhaled biguanides and mTOR inhibition for influenza and coronavirus (Review) The mammalian target of rapamycin (mTOR) signaling pathway senses and responds to nutrient availability, energy sufficiency, stress, hormones and mitogens to modulate protein synthesis. Rapamycin is a bacterial product that can inhibit mTOR via the PI3K/AKT/mTOR pathway. mTOR signaling is necessary for the development of influenza and modulates the antibody response to provide cross-protective immunity to lethal infection with influenza virus. In one human study, it was found that the treatment of severe H1N1 influenza‑related pneumonia with rapamycin and steroids improved the outcome. However, in other studies, immunosuppression with systemic steroids, and possibly rapamycin as well, was associated with an increased morbidity/mortality and a prolonged viral replication. In order to avoid the systemic side-effects, some investigators have postulated that the inhalation of rapamycin would be desirable. However, the inhalation of rapamycin, with its well-documented lung toxicity, could be contraindicated. Another class of drug, biguanides, can also inhibit mTOR, but have no lung toxicity. Biguanides are widely used small molecule drugs prescribed as oral anti-diabetics that have exhibited considerable promise in oncology. During the 1971 outbreak of influenza, diabetic patients treated with the biguanides, phenformin and buformin, had a lower incidence of infection than diabetics treated with sulfonylureas or insulin. Both buformin and phenformin reduce the mortality of influenza in mice; phenformin is less effective than buformin. The inhalation of buformin or phenformin for influenza may be an effective novel treatment strategy that would limit the risk of systemic side-effects associated with biguanides due to the low inhaled dose. Coronavirus disease 2019 (COVID-19) is an infectious disease caused by SARS-CoV-2, a virus closely related to the SARS virus. The disease is the cause of the 2019–2020 coronavirus outbreak. It is primarily spread between individuals via small droplets emitted from infected individuals when breathing or coughing. PI3K/AKT/mTOR signaling responses play important roles in MERS-CoV infection and may represent a novel drug target for therapeutic intervention strategies. The present review article discusses the effects of biguanides on influenza and coronavirus.

negative: COVID-19, diabetes mellitus and ACE2: The conundrum

negative: Not so fast: adaptive suppression of innate immunity The innate and adaptive immune systems act in concert to effectively combat infection while minimizing collater al damage caused by the host immune response. T cells of the adaptive immune system have now been shown to suppress overzealous early innate responses to infection that can lead to 'cytokine storm'–mediated death (pages 1248–1252).

negative: Production of a Monoclonal Antibody Targeting the M Protein of MERS-CoV for Detection of MERS-CoV Using a Synthetic Peptide Epitope Formulated with a CpG–DNA–Liposome Complex The Middle East respiratory syndrome-related coronavirus (MERS-CoV) contains four major structural proteins, the spike glycoprotein, nucleocapsid phosphoprotein, membrane (M) glycoprotein and small envelope glycoprotein. The M protein of MERS-CoV has a role in the morphogenesis or assembly of the virus and inhibits type I interferon expression in infected cells. Here, we produced a monoclonal antibody specific against the M protein of MERS-CoV by injecting BALB/c mice with a complex containing the epitope peptide and CpG–DNA encapsulated with a phosphatidyl-β-oleoyl-γ-palmitoyl ethanolamine (DOPE):cholesterol hemisuccinate (CHEMS). The monoclonal antibody was reactive to the epitope peptide of the M protein of MERS-CoV which was confirmed by western blotting and immunoprecipitations. Indirect immunofluorescence assay and confocal image analysis showed that the monoclonal antibody binds specifically to the M protein of MERS-CoV in the virus-infected cells. Further studies using this monoclonal antibody may provide important information on the function of the M protein and its future application in diagnostics.

negative: Molecular pathology of emerging coronavirus infections Respiratory viruses can cause a wide spectrum of pulmonary diseases, ranging from mild, upper respiratory tract infections to severe and life-threatening lower respiratory tract infections, including the development of acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). Viral clearance and subsequent recovery from infection require activation of an effective host immune response; however, many immune effector cells may also cause injury to host tissues. Severe acute respiratory syndrome (SARS) coronavirus and Middle East respiratory syndrome (MERS) coronavirus cause severe infection of the lower respiratory tract, with 10% and 35% overall mortality rates, respectively; however, >50% mortality rates are seen in the aged and immunosuppressed populations. While these viruses are susceptible to interferon treatment in vitro, they both encode numerous genes that allow for successful evasion of the host immune system until after high virus titres have been achieved. In this review, we discuss the importance of the innate immune response and the development of lung pathology following human coronavirus infection.

negative: ESPEN expert statements and practical guidance for nutritional management of individuals with SARS-CoV-2 infection The COVID-19 pandemics is posing unprecedented challenges and threats to patients and healthcare systems worldwide. Acute respiratory complications that require intensive care unit (ICU) management are a major cause of morbidity and mortality in COVID-19 patients. Patients with worst outcomes and higher mortality are reported to include immunocompromised subjects, namely older adults and polymorbid individuals and malnourished people in general. ICU stay, polymorbidity and older age are all commonly associated with high risk for malnutrition, representing per se a relevant risk factor for higher morbidity and mortality in chronic and acute disease. Also importantly, prolonged ICU stays are reported to be required for COVID-19 patients stabilization, and longer ICU stay may per se directly worsen or cause malnutrition, with severe loss of skeletal muscle mass and function which may lead to disability, poor quality of life and additional morbidity. Prevention, diagnosis and treatment of malnutrition should therefore be routinely included in the management of COVID-19 patients. In the current document, the European Society for Clinical Nutrition and Metabolism (ESPEN) aims at providing concise guidance for nutritional management of COVID-19 patients by proposing 10 practical recommendations. The practical guidance is focused to those in the ICU setting or in the presence of older age and polymorbidity, which are independently associated with malnutrition and its negative impact on patient survival.

negative: Use of Toll-Like Receptor 3 Agonists Against Respiratory Viral Infections Respiratory RNA viruses are constantly evolving, thus requiring development of additional prophylactic and therapeutic strategies. Harnessing the innate immune system to non-specifically respond to viral infection has the advantage of being able to circumvent viral mutations that render the virus resistant to a particular therapeutic agent. Viruses are recognized by various cellular receptors, including Toll-like receptor (TLR) 3 which recognizes double-stranded (ds)RNA produced during the viral replication cycle. TLR3 agonists include synthetic dsRNA such as poly (IC), poly (ICLC) and poly (AU). These agents have been evaluated and found to be effective against a number of viral agents. One major limitation has been the toxicity associated with administration of these drugs. Significant time and effort have been spent to develop alternatives/modifications that will minimize these adverse effects. This review will focus on the TLR3 agonist, poly (IC)/(ICLC) with respect to its use in treatment/prevention of respiratory viral infections.

negative: A double-inactivated whole virus candidate SARS coronavirus vaccine stimulates neutralising and protective antibody responses A double-inactivated, candidate whole virus vaccine against severe acute respiratory syndrome associated coronavirus (SARS-CoV) was developed and manufactured at large scale using fermenter cultures of serum protein free Vero cells. A two step inactivation procedure involving sequential formaldehyde and U.V. inactivation was utilised in order to ensure an extremely high safety margin with respect to residual infectivity. The immunogenicity of this double-inactivated vaccine was characterised in the mouse model. Mice that were immunised twice with the candidate SARS-CoV vaccine developed high antibody titres against the SARS-CoV spike protein and high levels of neutralising antibodies. The use of the adjuvant Al(OH)(3) had only a minor effect on the immunogenicity of the vaccine. In addition, cell mediated immunity as measured by interferon-γ and interleukin-4 stimulation, was elicited by vaccination. Moreover, the vaccine confers protective immunity as demonstrated by prevention of SARS-CoV replication in the respiratory tract of mice after intranasal challenge with SARS-CoV. Protection of mice was correlated to antibody titre against the SARS-CoV S protein and neutralising antibody titre.

negative: Immune Tolerance in Autoimmune Central Nervous System Disorders Multiple sclerosis (MS) afflicts genetically predisposed individuals and is associated with T lymphocyte-mediated damage to the myelin sheath of neurons in the central nervous system, resulting in severely impaired signal transmission. The mechanisms of the induction and manifestation of MS are not entirely understood. The control of autoimmune disorders is accomplished by both central tolerance in which autoreactive T lymphocytes are eliminated in the thymus and by tolerance mechanisms that operate in the periphery. Among the many mechanisms described, T regulatory (Treg) cells derived from the thymus (tTregs) and induced (iTregs) in the periphery as well as T regulatory type 1 cells (Tr1) are involved in many disease models. However, the precise details of the generation and perpetuation of these various Treg subsets and their relevance to the regulation of autoimmune diseases remain elusive. In this review, we critically analyze the current knowledge of the tolerance mechanisms involved in the regulation of MS and its animal model, experimental autoimmune encephalomyelitis.

negative: A Social Network Model of the COVID-19 Pandemic In the COVID-19 coronavirus pandemic, currently vaccines and specific anti-viral treatment are not yet available. Thus, preventing viral transmission by case isolation, quarantine, and social distancing is essential to slowing its spread. Here we model social networks using weighted graphs, where vertices represent individuals and edges represent contact. As public health measures are implemented, connectivity in the graph decreases, resulting in lower effective reproductive numbers, and reduced viral transmission. For COVID-19, model parameters were derived from the coronavirus epidemic in China, validated by epidemic data in Italy, then applied to the United States. We calculate that, in the U.S., the public is able to contain viral transmission by limiting the average number of contacts per person to less than 7 unique individuals over each 5 day period. This increases the average social distance between individuals to 10 degrees of separation.

negative: Enquête sérologique par immunofluorescence indirecte, sur les infections à coronavirus OC43 Summary Four-hundred seventy-two sera were examined by the indirect immunofluorescence test against Coronavirus strain OC43 adapted to the HRT18 cell culture. Sera were from children and adults hospitalized over a 4-year period, from 1979 to 1982, at the CHRU of Clermont-Ferrand (France) for different clinical reasons. Of the 446 sera tested, 61 % showed antibodies against OC43; 90 % of adult sera were positive. Coronavirus infections are very common in France. Immunity appears early in life, and infection is frequent in children from 12–36 months of age.

negative: Use of serological surveys to generate key insights into the changing global landscape of infectious disease

negative: Replication of a bovine coronavirus in organ cultures of foetal trachea Abstract A strain of bovine coronavirus (BC) adapted to tissue culture, was inoculated into organ cultures of bovine foetal trachea. Haemagglutinin in the fluid from infected organ cultures reached titres of 32 and characteristic coronavirus particles were observed electron microscopically. BC virus antigen was detected in frozen sections of the organ cultures by staining with fluorescent antibody. These data were evidence that BC virus replicated in organ cultures of respiratory tissue. The use of this technique for primary isolation of bovine coronaviruses from field material is discussed.

negative: Do COVID-19 patients admitted to the ICU require anti-Pneumocystis jirovecii prophylaxis? We are currently facing a frightening increase in COVID-19 patients admitted to the ICU. Aiming at screening for secondary pneumonia, we collected the data of our first twelve ICU patients who underwent bronchoalveolar lavage (BAL). Surprisingly, four were detected with Pneumocystis jirovecii (Pj) DNA and RNA, resulting in Pj prevalence of 17%. Pj is a ubiquitous ascomycetes fungus that thrives at the surface of type-I pneumocytes, specifically in human alveoli, leading to pneumocystosis in immunocompromised patients. Interestingly, none of our patients was immunocompromised per se before admission, while all presented the recognized risk factors for life-threatening COVID-19 infection. Observing such high prevalence in COVID-infected patients was unexpected. Almost all patients developed ARDS and received high-dose steroids to prevent worsening, as suggested by reports from China. In Pj-positive patients requiring steroids, prophylaxis was given to avoid the risk of pneumocystosis and increased lung inflammation that may compromise the outcome. We are strongly convinced that testing deep lung specimens for Pj in severe COVID-19 patients should be recommended and Pj-positive patients treated with steroids, and given anti-Pj prophylaxis. This message is important, given the high mortality rate of COVID-19 patients in the ICU.

negative: PD1-based DNA vaccine amplifies HIV-1 GAG-specific CD8+ T cells in mice. Viral vector-based vaccines that induce protective CD8+ T cell immunity can prevent or control pathogenic SIV infections, but issues of preexisting immunity and safety have impeded their implementation in HIV-1. Here, we report the development of what we believe to be a novel antigen-targeting DNA vaccine strategy that exploits the binding of programmed death-1 (PD1) to its ligands expressed on dendritic cells (DCs) by fusing soluble PD1 with HIV-1 GAG p24 antigen. As compared with non-DC-targeting vaccines, intramuscular immunization via electroporation (EP) of the fusion DNA in mice elicited consistently high frequencies of GAG-specific, broadly reactive, polyfunctional, long-lived, and cytotoxic CD8+ T cells and robust anti-GAG antibody titers. Vaccination conferred remarkable protection against mucosal challenge with vaccinia GAG viruses. Soluble PD1-based vaccination potentiated CD8+ T cell responses by enhancing antigen binding and uptake in DCs and activation in the draining lymph node. It also increased IL-12-producing DCs and engaged antigen cross-presentation when compared with anti-DEC205 antibody-mediated DC targeting. The high frequency of durable and protective GAG-specific CD8+ T cell immunity induced by soluble PD1-based vaccination suggests that PD1-based DNA vaccines could potentially be used against HIV-1 and other pathogens.

negative: Elevated expression of ACE2 in tumor-adjacent normal tissues of cancer patients The rapidly developing COVID-19 pandemic has raised a concern that cancer patients may have increased susceptibility to SARS-CoV-2 infection. This discussion has mostly focused on therapy-induced immune suppression. Here, we examined the expression patterns of ACE2, the receptor through which SARX-CoV2 enters human cells, and found that ACE2 mRNA levels are elevated in tumor-adjacent normal tissues of cancer patients, including in normal-adjacent lung tissues of lung cancer patients. These observations raise the possibility that the elevated COVID-19 risk of cancer patients may not be limited to those undergoing immune-suppressing treatment.

negative: Recombinant infectious bronchitis virus (IBV) H120 vaccine strain expressing the hemagglutinin-neuraminidase (HN) protein of Newcastle disease virus (NDV) protects chickens against IBV and NDV challenge Infectious bronchitis (IB) and Newcastle disease (ND) are common viral diseases of chickens, which are caused by infectious bronchitis virus (IBV) and Newcastle disease virus (NDV), respectively. Vaccination with live attenuated strains of IBV-H120 and NDV-LaSota are important for the control of IB and ND. However, conventional live attenuated vaccines are expensive and result in the inability to differentiate between infected and vaccinated chickens. Therefore, there is an urgent need to develop new efficacious vaccines. In this study, using a previously established reverse genetics system, we generated a recombinant IBV virus based on the IBV H120 vaccine strain expressing the haemagglutinin-neuraminidase (HN) protein of NDV. The recombinant virus, R-H120-HN/5a, exhibited growth dynamics, pathogenicity and viral titers that were similar to those of the parental IBV H120, but it had acquired hemagglutination activity from NDV. Vaccination of SPF chickens with the R-H120-HN/5a virus induced a humoral response at a level comparable to that of the LaSota/H120 commercial bivalent vaccine and provided significant protection against challenge with virulent IBV and NDV. In summary, the results of this study indicate that the IBV H120 strain could serve as an effective tool for designing vaccines against IB and other infectious diseases, and the generation of IBV R-H120-HN/5a provides a solid foundation for the development of an effective bivalent vaccine against IBV and NDV.

negative: Mucosal Immunization and Adjuvants The goal of the influenza vaccine is to prevent influenza virus infection and control the yearly seasonal epidemic and pandemic. However, the presently available parenteral influenza vaccine induces only systemic humoral immunity, which does not prevent influenza virus infection on the mucosal surface. Secretary IgA antibodies play an important role in preventing natural infection. Moreover, the IgA antibody response mediates cross-protection against variant viruses in animal models. Thus, a mucosal influenza vaccine that induces mucosal immunity would be a powerful tool to protect individuals from the influenza virus. Although the function of the mucosal immune system, especially in the respiratory tract, is not completely understood, there are several studies underway to develop mucosal influenza vaccines. Here, we will review current knowledge concerning the induction of IgA, the role of B-cell production of influenza virus specific IgA antibodies in anti-influenza immunity, and the role of humoral memory responses induced upon vaccination.

negative: Emerging and Reemerging Infectious Disease Threats

negative: The Potency of an Anti-MERS Coronavirus Subunit Vaccine Depends on a Unique Combinatorial Adjuvant Formulation Vaccination is one of the most successful strategies to prevent human infectious diseases. Combinatorial adjuvants have gained increasing interest as they can stimulate multiple immune pathways and enhance the vaccine efficacy of subunit vaccines. We investigated the adjuvanticity of Aluminum (alum) in combination with rASP-1, a protein adjuvant, using the Middle East respiratory syndrome coronavirus MERS-CoV receptor-binding-domain (RBD) vaccine antigen. A highly enhanced anti-MERS-CoV neutralizing antibody response was induced when mice were immunized with rASP-1 and the alum-adjuvanted RBD vaccine in two separate injection sites as compared to mice immunized with RBD + rASP-1 + alum formulated into a single inoculum. The antibodies produced also significantly inhibited the binding of RBD to its cell-associated receptor. Moreover, immunization with rASP-1 co-administered with the alum-adjuvanted RBD vaccine in separate sites resulted in an enhanced frequency of TfH and GC B cells within the draining lymph nodes, both of which were positively associated with the titers of the neutralizing antibody response related to anti-MERS-CoV protective immunity. Our findings not only indicate that this unique combinatorial adjuvanted RBD vaccine regimen improved the immunogenicity of RBD, but also point to the importance of utilizing combinatorial adjuvants for the induction of synergistic protective immune responses.

negative: Efficacy of glutathione therapy in relieving dyspnea associated with COVID-19 pneumonia: A report of 2 cases PURPOSE: Infection with COVID-19 potentially can result in severe outcomes and death from “cytokine storm syndrome”, resulting in novel coronavirus pneumonia (NCP) with severe dyspnea, acute respiratory distress syndrome (ARDS), fulminant myocarditis and multiorgan dysfunction with or without disseminated intravascular coagulation. No published treatment to date has been shown to adequately control the inflammation and respiratory symptoms associated with COVID-19, apart from oxygen therapy and assisted ventilation. We evaluated the effects of using high dose oral and/or IV glutathione in the treatment of 2 patients with dyspnea secondary to COVID-19 pneumonia. METHODS: Two patients living in New York City (NYC) with a history of Lyme and tick-borne co-infections experienced a cough and dyspnea and demonstrated radiological findings consistent with novel coronavirus pneumonia (NCP). A trial of 2 g of PO or IV glutathione was used in both patients and improved their dyspnea within 1 h of use. Repeated use of both 2000 mg of PO and IV glutathione was effective in further relieving respiratory symptoms. CONCLUSION: Oral and IV glutathione, glutathione precursors (N-acetyl-cysteine) and alpha lipoic acid may represent a novel treatment approach for blocking NF-κB and addressing “cytokine storm syndrome” and respiratory distress in patients with COVID-19 pneumonia.

negative: Scores of coronavirus vaccines are in competition - how will scientists choose the best?

negative: Novel coronavirus-related acute respiratory distress syndrome in a patient with twin pregnancy: A case report We present the case of a 39-year-old woman, G1P0, who had conceived twins via in-vitro fertilization, who presented at 27 weeks of gestation with nasal congestion and dry cough for 7 days. On presentation, her physical examination was benign, except for sinus tachycardia, and she was oxygenating adequately on room air. Laboratory studies were unremarkable, except a PCR test positive for SARS-COV2, and a CT scan of her chest showed bilateral multi-focal ground-glass opacities. A fetal non-stress test was reassuring. She was treated with intravenous fluids, ceftriaxone, azithromycin, and hydroxychloroquine. During her hospital stay, she developed progressively worsening respiratory failure, initially requiring non-invasive ventilation, and subsequently progressed to acute respiratory distress syndrome requiring mechanical ventilation. She then suffered from sudden hypoxemia and hemodynamic collapse, on maximal ventilatory support, prompting an emergency cesarean section at bedside. This led to rapid stabilization of hemodynamic parameters, and of her overall respiratory status. Both the twins were born prematurely, and one of them tested positive for SARS-COV2.

negative: Inclusive Costs of NPI Measures for COVID-19 Pandemic: Three Approaches The paper evaluates total inclusive costs of three public health approaches to address the COVID-19 epidemic in the US based on epidemiological projections in Ferguson et al (2020). We calculate and add costs of lost productivity and costs of mortality measured through the value of statistical life. We find that the aggressive approach which involves strict suppression measures and a drastic reduction of economic activity for three months with extensive testing and case tracking afterwards results in the lowest total costs for the society. The approach of doing no non-pharmaceutical measures results in the lowest total costs if the infection fatality rate falls below 0.15%.

negative: Defining trained immunity and its role in health and disease Immune memory is a defining feature of the acquired immune system, but activation of the innate immune system can also result in enhanced responsiveness to subsequent triggers. This process has been termed ‘trained immunity’, a de facto innate immune memory. Research in the past decade has pointed to the broad benefits of trained immunity for host defence but has also suggested potentially detrimental outcomes in immune-mediated and chronic inflammatory diseases. Here we define ‘trained immunity’ as a biological process and discuss the innate stimuli and the epigenetic and metabolic reprogramming events that shape the induction of trained immunity.

negative: DNA vaccine protection against SARS-CoV-2 in rhesus macaques The global COVID-19 pandemic caused by the SARS-CoV-2 virus has made the development of a vaccine a top biomedical priority. In this study, we developed a series of DNA vaccine candidates expressing different forms of the SARS-CoV-2 Spike (S) protein and evaluated them in 35 rhesus macaques. Vaccinated animals developed humoral and cellular immune responses, including neutralizing antibody titers comparable to those found in convalescent humans and macaques infected with SARS-CoV-2. Following vaccination, all animals were challenged with SARS-CoV-2, and the vaccine encoding the full-length S protein resulted in >3.1 and >3.7 log10 reductions in median viral loads in bronchoalveolar lavage and nasal mucosa, respectively, as compared with sham controls. Vaccine-elicited neutralizing antibody titers correlated with protective efficacy, suggesting an immune correlate of protection. These data demonstrate vaccine protection against SARS-CoV-2 in nonhuman primates.

negative: SARS-CoV-2 detection from nasopharyngeal swab samples without RNA extraction The ongoing COVID-19 pandemic has reached more than 200 countries and territories worldwide. Given the large requirement of SARS-CoV-2 diagnosis and considering that RNA extraction kits are in short supply, we investigated whether two commercial RT-qPCR kits were compatible with direct SARS-CoV-2 detection from nasopharyngeal swab samples. We show that one of the tested kits is fully compatible with direct SARS-CoV-2 detection suggesting that omission of an RNA extraction step should be considered in SARS-CoV-2 diagnosis.

negative: Enteric Immunity Happy Gut, Healthy Animal In this article, key concepts important for enteric immunity are discussed. The gastrointestinal tract is the largest immune organ of the body. The mucosal barrier, the tight junctions and the “kill zone,” along with the gut mucosa and maintaining an “anti-inflammatory” state are essential for “good gut health.” The microbiome, the microorganisms in the gastrointestinal tract, which has more cells then the entire animal’s body, is essential for immune development, immune response, and maximizing ruminant productivity. Direct-fed microbials aid in both microbiome stability “homeostasis” and immune function.

negative: Research and Development on Therapeutic Agents and Vaccines for COVID-19 and Related Human Coronavirus Diseases Since the outbreak of the novel coronavirus disease COVID-19, caused by the SARS-CoV-2 virus, this disease has spread rapidly around the globe. Considering the potential threat of a pandemic, scientists and physicians have been racing to understand this new virus and the pathophysiology of this disease to uncover possible treatment regimens and discover effective therapeutic agents and vaccines. To support the current research and development, CAS has produced a special report to provide an overview of published scientific information with an emphasis on patents in the CAS content collection. It highlights antiviral strategies involving small molecules and biologics targeting complex molecular interactions involved in coronavirus infection and replication. The drug-repurposing effort documented herein focuses primarily on agents known to be effective against other RNA viruses including SARS-CoV and MERS-CoV. The patent analysis of coronavirusrelated biologics includes therapeutic antibodies, cytokines, and nucleic acid-based therapies targeting virus gene expression as well as various types of vaccines. More than 500 patents disclose methodologies of these four biologics with the potential for treating and preventing coronavirus infections, which may be applicable to COVID-19. The information included in this report provides a strong intellectual groundwork for the ongoing development of therapeutic agents and vaccines.

negative: Current State and Predicting Future Scenario of Highly Infected Nations for COVID-19 Pandemic Since the first report of COVID-19 from Wuhan China, the virus has rapidly spread across the globe now presently reported in 177 countries with positive cases crossing 400 thousand and rising. In the current study, prediction is made for highly infected countries by a simple and novel method using only cumulative positive cases reported. The rate of infection per week (R_w) coefficient delineated three phases for the current COVID-19 pandemic. All the countries under study have passed Phase 1 and are currently in Phase 2 except for South Korea which is in Phase 3. Early detection with rapid and large-scale testing helps in controlling the COVID-19 pandemic. Staying in Phase 2 for longer period would lead to increase in COVID-19 positive cases.

negative: Memory of mice and men: CD8(+) T‐cell cross‐reactivity and heterologous immunity Summary: The main functions of memory T cells are to provide protection upon re‐exposure to a pathogen and to prevent the re‐emergence of low‐grade persistent pathogens. Memory T cells achieve these functions through their high frequency and elevated activation state, which lead to rapid responses upon antigenic challenge. The significance and characteristics of memory CD8(+) T cells in viral infections have been studied extensively. In many of these studies of T‐cell memory, experimental viral immunologists go to great lengths to assure that their animal colonies are free of endogenous pathogens in order to design reproducible experiments. These experimental results are then thought to provide the basis for our understanding of human immune responses to viruses. Although these findings can be enlightening, humans are not immunologically naïve, and they often have memory T‐cell populations that can cross‐react with and respond to a new infectious agent or cross‐react with allo‐antigens and influence the success of tissue transplantation. These cross‐reactive T cells can become activated and modulate the immune response and outcome of subsequent heterologous infections, a phenomenon we have termed heterologous immunity. These large memory populations are also accommodated into a finite immune system, requiring that the host makes room for each new population of memory cell. It appears that memory cells are part of a continually evolving interactive network, where with each new infection there is an alteration in the frequencies, distributions, and activities of memory cells generated in response to previous infections and allo‐antigens.

negative: ESICM 2013 - Abstracts of Oral Presentations and Poster Sessions

negative: Forecasting the timeframe of coronavirus and human cells interaction with reverse engineering Abstract In December 2019, an atypical pneumonia invaded the city of Wuhan, China, and the causative agent of this disease turned out to be a new coronavirus. In January 2020, the World Health Organization named the new coronavirus 2019-nCoV and subsequently it is referred to as SARS-CoV2 and the related disease as CoViD-19 [9]. Very quickly, the epidemic led to a pandemic and it is now a worldwide emergency requiring the creation of new antiviral therapies and a related vaccine. The purpose of this article is to review and investigate further the molecular mechanism by which the SARS-CoV2 virus infection proceeds via the formation of a hetero-trimer between its protein S, the ACE2 receptor and the B0AT1 protein, which is the “entry receptor” for the infection process involving membrane fusion [10]. A reverse engineering process uses the formalism of the Hill function to represent the functions related to the dynamics of the biochemical interactions of the viral infection process. Then, using a logical evaluation of viral density that measures the rate at which the cells are hijacked by the virus (and they provide a place for the virus to replicate) and considering the “time delay” given by the interaction between cell and virus, the expected duration of the incubation period is predicted. The conclusion is that the density of the virus varies from the “exposure time” to the “interaction time” (virus-cells). This model can be used both to evaluate the infectious condition and to analyze the incubation period. Background The ongoing threat of the new coronavirus SARS-CoV2 pandemic is alarming and strategies for combating infection are highly desired. This RNA virus belongs to the β-coronavirus genus and is similar in some features to SARS-CoV. Currently, no vaccine or approved medical treatment is available. The complex dynamics of the rapid spread of this virus can be demonstrated with the aid of a computational framework. Methods A mathematical model based on the principles of cell-virus interaction is developed in this manuscript. The amino acid sequence of S proein and its interaction with the ACE-2 protein is mimicked with the aid of Hill function. The mathematical model with delay is solved with the aid of numerical solvers and the parametric values are obtained with the help of MCMC algorithm. Results A delay differential equation model is developed to demonstrate the dynamics of target cells, infected cells and the SARS-CoV2. The important parameters and coefficients are demonstrated with the aid of numerical computations. The resulting thresholds and forecasting may prove to be useful tools for future experimental studies and control strategies. Conclusions From the analysis, I is concluded that control strategy via delay is a promising technique and the role of Hill function formalism in control strategies can be better interpreted in an inexpensive manner with the aid of a theoretical framework.

negative: LY6E impairs coronavirus fusion and confers immune control of viral disease Zoonotic coronaviruses (CoVs) are significant threats to global health, as exemplified by the recent emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)1. Host immune responses to CoV are complex and regulated in part through antiviral interferons. However, the interferon-stimulated gene products that inhibit CoV are not well characterized2. Here, we show that interferon-inducible lymphocyte antigen 6 complex, locus E (LY6E) potently restricts cellular infection by multiple CoVs, including SARS-CoV, SARS-CoV-2, and Middle East respiratory syndrome coronavirus (MERS-CoV). Mechanistic studies revealed that LY6E inhibits CoV entry into cells by interfering with spike protein-mediated membrane fusion. Importantly, mice lacking Ly6e in hematopoietic cells were highly susceptible to murine CoV infection. Exacerbated viral pathogenesis in Ly6e knockout mice was accompanied by loss of hepatic and splenic immune cells and reduction in global antiviral gene pathways. Accordingly, we found that Ly6e directly protects primary B cells and dendritic cells from murine CoV infection. Our results demonstrate that LY6E is a critical antiviral immune effector that controls CoV infection and pathogenesis. These findings advance our understanding of immune-mediated control of CoV in vitro and in vivo, knowledge that could help inform strategies to combat infection by emerging CoV.

negative: SARS-CoV-2: an Emerging Coronavirus that Causes a Global Threat An ongoing outbreak of pneumonia caused by a novel coronavirus, currently designated as the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), was reported recently. However, as SARS-CoV-2 is an emerging virus, we know little about it. In this review, we summarize the key events occurred during the early stage of SARS-CoV-2 outbreak, the basic characteristics of the pathogen, the signs and symptoms of the infected patients as well as the possible transmission pathways of the virus. Furthermore, we also review the current knowledge on the origin and evolution of the SARS-CoV-2. We highlight bats as the potential natural reservoir and pangolins as the possible intermediate host of the virus, but their roles are waiting for further investigation. Finally, the advances in the development of chemotherapeutic options are also briefly summarized.

negative: COVID-19 (Coronavirus Disease-19): Traditionelle Chinesische Medizin einschließlich Akupunktur zur Linderung — Ein Bericht aus Wuhan, Hubei Provinz in China

negative: Construction of Armored RNA Containing Long-Size Chimeric RNA by Increasing the Number and Affinity of the Pac Site in Exogenous RNA and Sequence Coding Coat Protein of the MS2 Bacteriophage OBJECTIVES: To construct a one-plasmid expression system of the armored RNA containing long chimeric RNA byincreasing the number and affinity of the pac site. METHODS: The plasmid pET-MS2-pac was constructedwith one C-variant pac site, and then the plasmid pM-CR-2C containing 1,891-bp chimeric sequences and two C-variant pac sites was produced. Meanwhile, three plasmids (pM-CR-C, pM-CR-2W and pM-CR-W) were obtained as parallel controls with a different number and affinity of the pac site. Finally, the armored RNA was expressed and purified. RESULTS: The armored RNA with 1,891 bases target RNA was expressed successfully by the one-plasmid expression system with two C-variant pac sites, while for one pac site, no matter whether the affinity was changed or not, only the 1,200 bases target RNA was packaged. It was also found that the C-variant pac site could increase the expression efficiency of the armored RNA. The armored RNA with 1,891-bp exogenous RNA in our study showed the characterization of ribonuclease resistance and stability at different time points and temperature conditions. CONCLUSIONS: The armored RNA with 1,891 bases exogenous RNA was constructed and the expression system can be used as a platform for preparation of the armored RNA containing long RNA sequences.

negative: A proposal for the return to routine endoscopy during the COVID-19 pandemic Abstract In response to the COVID-19 pandemic, many jurisdictions and gastroenterological societies around the world have suspended nonurgent endoscopy. Subject to country-specific variability, it is projected that with current mitigation measures in place, the peak incidence of active COVID-19 infections may be delayed by over 6 months. Although this aims to prevent the overburdening of healthcare systems, prolonged deferral of elective endoscopy will become unsustainable. Herein, we propose that by incorporating readily available point-of-care tests and conducting accurate clinical risk assessments, a safe and timely return to elective endoscopy is feasible. Our algorithm not only focuses on the safety of patients and healthcare workers, but also assists in rationalizing the use of invaluable resources such as personal protective equipment.

negative: Induction of SARS-nucleoprotein-specific immune response by use of DNA vaccine Abstract Induction of effective cytotoxic T lymphocyte (CTL) and/or a specific antibody against conserved viral proteins may be essential to the development of a safe and effective severe acute respiratory syndrome coronavirus (SARS-Cov) vaccine. DNA vaccination represents a new strategy for induction of humoral and cellular immune response. To determine the ability of SARS-Cov nucleoprotein (N protein) to induce antiviral immunity, in this report, we established a stable C2C12 line expressing SARS-Cov N protein, which was used as a target for specific CTL assay. We also expressed recombinant N proteins in Escherichia coli and prepared N protein-specific polyclonal antibodies. C3H/He mice were immunized with N protein-expressible pcDN-fn vector by intramuscular injections. We found that the DNA vaccination induced both N protein-specific antibody and specific CTL activity to the target. When C3H/He mice were immunized by three separate injections, high antibody titre (1:3200–1:6400, average titre is 1:4580) and high CTL activity (67.4±8.4% (E:T=25:1), 69.6±6.7% (E:T=50:1) and 71.8±6.2% (E:T=100:1)) were observed. In the case of two vaccine injections, CTL activity was also high (56.6±12.7% (E:T=25:1), 57.4±11.7% (E:T=50:1) and 63.0±6.3% (E:T=100:1)). However, antibody titres were much lower (1:200–1:3200, average titre is 1:980). Our results suggest that SARS-Cov nucleocapsid gene might be a candidate gene for SARS DNA vaccination.

negative: Financing Vaccines for Global Health Security Recent outbreaks of infectious pathogens such as Zika, Ebola, and COVID-19 have underscored the need for the dependable availability of vaccines against emerging infectious diseases (EIDs). The cost and risk of R&D programs and uniquely unpredictable demand for EID vaccines have discouraged vaccine developers, and government and nonprofit agencies have been unable to provide timely or sufficient incentives for their development and sustained supply. We analyze the economic returns of a portfolio of EID vaccine assets, and find that under realistic financing assumptions, the expected returns are significantly negative, implying that the private sector is unlikely to address this need without public-sector intervention. We have sized the financing deficit for this portfolio and propose several potential solutions, including price increases, enhanced public-private partnerships, and subscription models through which individuals would pay annual fees to obtain access to a portfolio of vaccines in the event of an outbreak.

negative: Global profiling of SARS-CoV-2 specific IgG/ IgM responses of convalescents using a proteome microarray COVID-19 is caused by SARS-CoV-2, and has become a global pandemic. There is no highly effective medicine or vaccine, most of the patients were recovered by their own immune response, especially the virus specific IgG and IgM responses. However, the IgG/ IgM responses is barely known. To enable the global understanding of SARS-CoV-2 specific IgG/ IgM responses, a SARS-CoV-2 proteome microarray with 18 out of the 28 predicted proteins was constructed. The microarray was applied to profile the IgG/ IgM responses with 29 convalescent sera. The results suggest that at the convalescent phase 100% of patients had IgG/ IgM responses to SARS-CoV-2, especially to protein N, S1 but not S2. S1 purified from mammalian cell demonstrated the highest performance to differentiate COVID-19 patients from controls. Besides protein N and S1, significant antibody responses to ORF9b and NSP5 were also identified. In-depth analysis showed that the level of S1 IgG positively correlate to age and the level of LDH (lactate dehydrogenase), especially for women, while the level of S1 IgG negatively correlate to Ly% (Lymphocyte percentage). This study presents the first whole picture of the SARS-CoV-2 specific IgG/ IgM responses, and provides insights to develop precise immuno-diagnostics, effective treatment and vaccine.

negative: Commensal enteric bacteria lipopolysaccharide impairs host defense against disseminated Candida albicans fungal infection Commensal enteric bacteria maintain systemic immune responsiveness that protects against disseminated or localized infection in extra-intestinal tissues caused by pathogenic microbes. However, since shifts in infection susceptibility after commensal bacteria eradication have primarily been probed using viruses, the broader applicability to other pathogen types remains undefined. In sharp contrast to diminished antiviral immunity, we show commensal bacteria eradication bolsters protection against disseminated Candida albicans fungal infection. Enhanced antifungal immunity reflects more robust systemic expansion of Ly6G(hi)Ly6C(int) neutrophils, and their mobilization into infected tissues among antibiotic treated compared with commensal bacteria replete control mice. Reciprocally, depletion of neutrophils from expanded levels or intestinal LPS reconstitution overrides the antifungal protective benefits conferred by commensal bacteria eradication. This discordance in antifungal compared with antiviral immunity highlights intrinsic differences in how commensal bacteria control responsiveness for specific immune cell subsets because pathogen-specific CD8(+) T cells that protect against viruses were suppressed similarly after C. albicans and influenza A virus infection. Thus, positive calibration of antiviral immunity by commensal bacteria is counterbalanced by restrained activation of other immune components that confer antifungal immunity.

negative: Teicoplanin potently blocks the cell entry of 2019-nCoV Since December 2019, the outbreak of a new coronavirus, named 2019-nCoV, has greatly threatened the public health in China and raised great concerns worldwide. No specific treatment for this infection is currently available. We previously reported that teicoplanin, a glycopeptide antibiotic which has routinely been used in the clinic to treat bacterial infection with low toxicity, significantly inhibits the invasion of cells by Ebola virus, SARS-CoV and MERS-CoV, via specifically inhibiting the activity of cathepsin L. Here, we tested the efficacy of teicoplanin against 2019-nCoV virus infection and found that teicoplanin potently prevents the entrance of 2019-nCoV-Spike-pseudoviruses into the cytoplasm, with an IC50 of 1.66 μM. Although the inhibitory effect upon the replication of wildtype viruses ex vivo and in vivo remains to be determined, our preliminary result indicates that the potential antiviral activity of teicoplanin could be applied for the treatment of 2019-nCoV virus infection.

negative: Enteric Viruses Many viruses use the enteric tract as a route of entry to the human, animal, or avian host. The onset of acute enteritis is associated with infection by viruses that replicate at or near the site of entry into the intestinal mucosa, including caliciviruses, rotaviruses, adenoviruses, astroviruses, and coronaviruses. These ‘enteric’ viruses occur globally and share similar features. Most are RNA viruses that replicate in the cytoplasm of mature absorptive epithelial cells lining the villi of the small intestine, leading to inflammation and villus atrophy. Vomiting and diarrhea can result in dehydration and death if untreated. Despite abundant growth in vivo, they initially proved difficult or impossible to grow in vitro. Most are genetically diverse, species specific, highly infectious within species and transmitted by the fecal–oral route. Severe symptoms are most commonly associated with primary infections of young animals, and are followed by short-lived immunity. Reinfections are common throughout life, but are often only mildly symptomatic. Safe and effective vaccines have been developed to prevent severe rotavirus disease in young children. In addition to these enterotropic viruses, enteric disease can also result from spread to the intestine of HIV or cytomegaloviruses during the later stages of systemic disease in immunocompromised hosts.

negative: The infection evidence of SARS-COV-2 in ocular surface： a single-center cross-sectional study Purpose: The aim of this study was to identify whether SARS-COV-2 infected in ocular surface. Methods: Cross-sectional study of patients presenting for who received a COVID-19 diagnosis, from December 30, 2019 to February 7, 2020, at Tongji hospital, Tongji medical college, Huazhong University of Science and Technology. Demographics, temperature was recorded, blood routine test (Rt), chest Computed Tomography (CT) were took intermittently, and SARS-COV-2 real-time reverse-transcriptase-polymerase-chain-reaction (RT-PCR) assay were arranged for the nasopharyngeal and conjunctival swab samples. Results: A total of 102 patients (48 Male [50%] and 54 Female [50%]) with clinical symptoms, Rt, and chest Computed Tomography (CT) abnormalities were identified with a clinical diagnosis of COVID-19. Patients had a mean [SD] gestational age of 57.63 [14.90] years. Of a total of 102 patients identified, 72 patients (36 men [50%] and 36 women [50%]; mean [SD] age, 58.68 [14.81] years) confirmed by laboratory diagnosis with SARS-COV-2 RT-PCR assay. Only two patients (2.78%) with conjunctivitis was identified from 72 patients with a laboratory confirmed COVID-19. However, SARS-COV-2 RNA fragments was found in ocular discharges by SARS-COV-2 RT-PCR only in one patient with conjunctivitis. Conclusions: Although we suspect the incidence of SARS-COV-2 infection through the ocular surface is extremely low, the nosocomial infection of SARS-CoV-2 through the eyes after occupational exposure is a potential route. The inefficient diagnostic method and the sampling time lag may contribute to the lower positive rate of conjunctival swab samples of SARS-COV-2. Therefore, to lower the SARS-COV-2 nosocomial infection, the protective goggles should be wore in all the health care workers.

negative: Role of oxidized LDL-induced “trained macrophages” in the pathogenesis of COVID-19 and benefits of pioglitazone: A hypothesis BACKGROUND AND AIMS: Older adults and people who have cardiovascular disorders (their common pathogenetic mechanism is progressive atherosclerosis) are at higher risk for severe illness from COVID-19 (coronavirus disease 2019). Their common pathogenetic mechanism is progressive atherosclerosis in which oxLDL (oxidized LDL) plays major role. Receptor-mediated uptake of oxLDL by the monocyte-derived macrophages activates the long-term epigenetic reprogramming of innate immunity, which is termed “trained immunity.” The aim of this work is to investigate the mechanisms and treatment possibilities that can control the activities of these specific macrophages. METHODS: Search in Medline and PubMed relevant articles on the trained immunity and cytokine storm of COVID-19. CONCLUSIONS: When oxLDL-trained macrophages encounter SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) in the lung, it causes unregulated cytokine secretion, leading to the alveolar damage. Therefore, blocking macrophage training by pioglitazone, a thiazolidinedione, could control the hyperactivation that the virus would trigger.

negative: A fast and simple one-step duplex PCR assay for canine distemper virus (CDV) and canine coronavirus (CCoV) detection The one-step polymerase chain reaction (one-step PCR) detection assay is an innovative PCR detection method, eliminating nucleic acid extraction steps, in which samples can be directly added to PCR reagents for testing. For simultaneous detection of CDV and CCoV, a sensitive and specific one-step duplex PCR (one-step dPCR) assay was developed with two pairs of primers that were designed based on H and M gene sequences of CDV and CCoV, respectively. The one-step dPCR with optimized detection conditions has high specificity and sensitivity; independent sequencing assays further verified these results.

negative: Infections, connective tissue diseases and vasculitis. In genetically predisposed individuals, viruses, bacteria, or parasitic infectious agents are suspected of inducing autoimmunity and/or exacerbating autoimmune rheumatic diseases (ARD) once self-tolerance is broken. Although direct evidence for this association is still lacking, numerous data from animal models as well as from humans support the hypothesis of a direct contribution of pathogens to the induction of several ARD. This review focuses on the possible role of infectious agents as triggers of autoimmunity in systemic lupus erythematosus, polymyositis-dermatomyositis, antiphospholipid antibody syndrome, and primary vasculitis. Indeed, vasculitis may be a clinical manifestation of an infectious disease (secondary vasculitis). In addition, immune response abnormalities and immunosuppressive medications may be responsible for the high percentage of infectious complications in ARD patients. Recent therapeutic approaches aimed at lowering doses of cytotoxic agents and shortening duration of treatment with the most toxic drugs, have proved to be as effective as conventional regimens. New drugs and strategies aimed at preventing infections could further improve the outcome of ARD patients.

negative: “Healthy Hajj 2019” –– what you need to know, before you go

negative: Induction of lactogenic immunity to transmissible gastroneteritis virus of swine using an attenuated coronavirus mutant able to survive in the physicochemical environment of the digestive tract Abstract A trasmissible gastroenteritis (TGE) coronavirus mutant (188-SG), selected as attenuated and resistant to acidity and proteases of the digestive tract of adult pigs, was used as vaccine (“Nouzilly strain”) in sows to protect suckling piglets against a challenge exposure carried out with a higly virulent TGEV strain. The pregnant sows were immunized once (42–49 days before farrowing) or twice (42–49 and 7–15 days before farrowing) by the oral, intramuscular or conjunctival route with the 188-SG strain. Sows exposed to virulent TGEV in the field and experimentally infected sows (two oral inoculations during pregnancy) were used as positive controls leading to high protection. The neutralizing antibody response to vaccination and/or infection was studied in serum and milk. No protection against mortality was observed in the litters of (1) the nine seronegative, susceptible sows, with piglet mortality of 65/70, (2) the seven once orally vaccinated sows, with mortality of 44/54, (3) the seven sows vaccinated twice by the conjunctival route, with mortality of 55/76. Moderate protection was observed in (1) the eight sows vaccinated intramuscularly twice with piglet mortality of 36/90, (2) the seven orally and intramuscularly vaccinated sows with piglet mortality of 31/51. In contrast, improved protection was observed in (1) the 10 sows vaccinated twice orally, with piglet mortality of 23/95, (2) the four naturally infected sows with piglet mortality of 6/41, (3) the six sows experimentally infected with virulent TGEV with piglet mortality of 1/59. No correlation was found between neutralizing antibodies titers in serum and milk and protection rate of the piglets. The results indicate that relative protective lactogenic immunity against TGEV is induced only by repeated ingestion of -SG attenuated 188-SG strain of TGEV.

negative: Master manipulators: how herpesviruses alter immune responses to RSV In this commentary on “A gammaherpesvirus licenses CD8 T cells to protect the host from pneumovirus-induced immunopathologies”, the authors highlight the growing literature suggesting that herpesvirus infections shape subsequent immune responses to other pathogens, especially by broadening CD8+T-cell responses. These observations have implications for vaccine development against other important pathogens, such as Respiratory Syncytial Virus.

negative: Estimating the burden of SARS-CoV-2 in France France has been heavily affected by the SARS-CoV-2 epidemic and went into lockdown on the 17th March 2020. Using models applied to hospital and death data, we estimate the impact of the lockdown and current population immunity. We find 2.6% of infected individuals are hospitalized and 0.53% die, ranging from 0.001% in those <20y to 8.3% in those >80y. Across all ages, men are more likely to be hospitalized, enter intensive care, and die than women. The lockdown reduced the reproductive number from 3.3 to 0.5 (84% reduction). By 11 May, when interventions are scheduled to be eased, we project 3.7 million (range: 2.3-6.7) people, 5.7% of the population, will have been infected. Population immunity appears insufficient to avoid a second wave if all control measures are released at the end of the lockdown.

negative: Face mask use in the general population and optimal resource allocation during the COVID-19 pandemic The ongoing novel coronavirus disease (COVID-19) pandemic has rapidly spread in early 2020, causing tens of thousands of deaths, over a million cases and widespread socioeconomic disruption. With no vaccine available and numerous national healthcare systems reaching or exceeding capacity, interventions to limit transmission are urgently needed. While there is broad agreement that travel restrictions and closure of non-essential businesses and schools are beneficial in limiting local and regional spread, recommendations around the use of face masks for the general population are less consistent internationally. In this study, we examined the role of face masks in mitigating the spread of COVID-19 in the general population, using epidemic models to estimate the total reduction of infections and deaths under various scenarios. In particular, we examined the optimal deployment of face masks when resources are limited, and explored a range of supply and demand dynamics. We found that face masks, even with a limited protective effect, can reduce infections and deaths, and can delay the peak time of the epidemic. We consistently found that a random distribution of masks in the population was a suboptimal strategy when resources were limited. Prioritizing coverage among the elderly was more beneficial, while allocating a proportion of available resources for diagnosed infected cases provided further mitigation under a range of scenarios. In summary, face mask use, particularly for a pathogen with relatively common asymptomatic carriage, can effectively provide some mitigation of transmission, while balancing provision between vulnerable healthy persons and symptomatic persons can optimize mitigation efforts when resources are limited.

negative: Immune-epidemiological parameters of the novel coronavirus – a perspective Introduction: At the end of 2019, Wuhan, a city in China with a population of about 11 million, witnessed the outbreak of unusual pneumonia. As of 29 March 2020, the disease has spread to more 199 countries and territories worldwide. The 2019 novel coronavirus, 2019-nCoV, is known as the probable causative agent of the illness. Areas covered: Here, the epidemiological dynamics of the coronavirus disease 2019 (COVID-19) that stand in close relation to distinct immunogenetic characters of the pathogen are discussed, to understand the ability and inability of the immune system in combatting COVID-19. Expert opinion: The elderly population is at increased risk of developing and dying from COVID-19. Comorbidity is present in more than 30% of cases with COVID-19. Except for less than 1% of the total, a chronic condition has been found in all cases that died from COVID-19. Men are more than 1.5 times more likely to die from COVID-19. Evidence links aging to cytokine dysregulation and T-cell repertoire reduction, male population to relatively reduced anti-viral immunity, and COVID-19-related comorbidities to hyper inflammation. The transmission of COVID-19 is influenced by the host-related factors that are known to be associated with immune dysregulation.

negative: Viral Innate Immune Evasion and the Pathogenesis of Emerging RNA Virus Infections Positive-sense single-stranded RNA (+ssRNA) viruses comprise many (re-)emerging human pathogens that pose a public health problem. Our innate immune system and, in particular, the interferon response form the important first line of defence against these viruses. Given their genetic flexibility, these viruses have therefore developed multiple strategies to evade the innate immune response in order to optimize their replication capacity. Already many molecular mechanisms of innate immune evasion by +ssRNA viruses have been identified. However, research addressing the effect of host innate immune evasion on the pathology caused by viral infections is less prevalent in the literature, though very relevant and interesting. Since interferons have been implicated in inflammatory diseases and immunopathology in addition to their protective role in infection, antagonizing the immune response may have an ambiguous effect on the clinical outcome of the viral disease. Therefore, this review discusses what is currently known about the role of interferons and host immune evasion in the pathogenesis of emerging coronaviruses, alphaviruses and flaviviruses.

negative: T-cell apoptosis in autoimmune diseases: termination of inflammation in the nervous system and other sites with specialized immune-defense mechanisms Abstract We have studied T-cell apoptosis in animal models of human autoimmune disorders of the nervous system and in other tissues devoid of specialized immune-defense mechanisms. Our data suggest that the CNS has high potential for elimination of T-cell-dependent inflammation, whereas this mechanism is less effective in the PNS, and is almost absent in other tissues such as muscle and skin. Interestingly, several conventional and novel immunotherapeutic approaches, such as glucocorticosteroid and high-dose antigen therapy, induce T-cell apoptosis in situ. In vitro experiments suggest different scenarios for the mechanisms by which specific cellular and humoral elements in the nervous system synergize and sensitize T cells for apoptosis in vivo. We also discuss regulatory, proapoptotic mechanisms, such as the Fas–FasL system and galectin-1, that have been utilized in other tissues to mediate immune protection.

negative: Investigating the likely association between genetic ancestry and COVID-19 manifestation The novel coronavirus 2019-nCoV/SARS-CoV-2 infection has shown discernible variability across the globe. While in some countries people are recovering relatively quicker, in others, recovery times have been comparatively longer and numbers of those succumbing to it high. In this study, we aimed to evaluate the likely association between an individual's ancestry and the extent of COVID-19 manifestation employing Europeans as the case study. We employed 10,215 ancient and modern genomes across the globe assessing 597,573 single nucleotide polymorphisms (SNPs). Pearson's correlation coefficient (r) between various ancestry proportions of European genomes and COVID-19 death/recovery ratio was calculated and its significance was statistically evaluated. We found significant positive correlation (p=0.03) between European Mesolithic hunter gatherers (WHG) ancestral fractions and COVID-19 death/recovery ratio and a marginally significant negative correlation (p=0.06) between Neolithic Iranian ancestry fractions and COVID-19 death/recovery ratio. We further identified 404 immune response related single nucleotide polymorphisms (SNPs) by comparing publicly available 753 genomes from various European countries against 838 genomes from various Eastern Asian countries in a genome wide association study (GWAS). Prominently we identified that SNPs associated with Interferon stimulated antiviral response, Interferon-stimulated gene 15 mediated antiviral mechanism and 2'-5' oligoadenylate synthase mediated antiviral response show large differences in allele frequencies between Europeans and East Asians. Overall, to the best of our knowledge, this is the first study evaluating the likely association between genetic ancestry and COVID-19 manifestation. While our current findings improve our overall understanding of the COVID-19, we note that the development of effective therapeutics will benefit immensely from a more detailed analyses of individual genomic sequence data from COVID-19 patients of varied ancestries.

negative: CHAPTER 4 Keeping Track of Viruses Publisher Summary This chapter introduces basic concepts of virology and exemplifies the usage of current technology for identifying and tracking viral pathogens. Virus structure, lifestyle, replication strategies, classication, the varied modes of transmission, infection, and disease manifestations are focussed upon in the chapter. Viruses are extremely simple “life” forms without metabolic capacity, organelles, translational machinery, or autonomous replicative potential; the essential elements of a virus are consequently minimal. A virus enters the host through any opportunistic opening of the body—; such as minute breaks in the skin barrier or mucosal linings of the eye, nose, etc. Antibodies produced during an infection often have the ability to bind the virus and reduce infectivity. An immediate question to solve during a virus outbreak is the mechanism by which the virus spreads. Viruses frequently infect animal or insect vectors that serve to pass the virus to humans. By identifying the virus through sequence analysis, a hypothetical reservoir can be predicted by the placement of the sequence on the phylogenetic tree‥ The varied modes of transmission, infection, and disease manifestations as they relate to the different diagnostic methods for virus identification are highlighted. Examples of naturally emerging viruses; such as Sin Nombre, Nipah, West Nile conclude the chapter. New technologies that allow the creation of manmade or “engineered” viruses, new frontiers in viral diagnostics, and a few thoughts on the future of virology are also presented. The global eradication of smallpox ranks as one of humankind's greatest accomplishments yet many viral challenges remain. HIV, hepatitis B and C, influenza, dengue, rotavirus, and many other viral diseases continue to affect tens of millions.

negative: Mechanism of inflammatory response in associated comorbidities in COVID-19 BACKGROUND AND AIMS: The outbreak of the new coronavirus, SARS-CoV-2, causes a respiratory disease and individuals with pre-existing cardiometabolic disorders display worse prognosis through the infection course. The aim of this minireview is to present epidemiological data related to metabolic comorbidities in association with the SARS-CoV-2. METHODS: This is a narrative mini-review with Pubmed search until April 23, 2020 using the keywords COVID-19, SARS-CoV-2, treatment of coronavirus and following terms: diabetes mellitus, obesity, arterial hypertension, ACE-inhibitors, cytokine storm, immune response and vitamin D. RESULTS: Studies indicate that obese individuals are more likely to develop infections, and that adipose tissue serves as a pathogen reservoir. In diabetic individuals higher rate of inflammatory processes is seen due to constant glucose recognition by C type lectin receptors. Hypertensive individuals, usually grouped with other conditions, are treated with drugs to reduce blood pressure mostly through ACEi and ARB, that leads to increased ACE2 expression, used by SARS-CoV-2 for human's cell entry. Until now, the studies have shown that individuals with those conditions and affected by COVID-19 present an uncontrolled release of pro-inflammatory cytokines and an unbalanced immune response, leading to the cytokine storm phenomenon. Vitamin D is highlighted as a potential therapeutic target, because in addition to acting on the immune system, it plays an important role in the control of cardiometabolic diseases. CONCLUSION: Currently, since there is no proven and effective antiviral therapy for SARS-CoV-2, the efforts should focus on controlling inflammatory response and reduce the risks of associated complications.

negative: Managing Cutaneous Immune-Mediated Diseases During the COVID-19 Pandemic Coronavirus disease 2019 (COVID-19) is a clinical syndrome caused by a novel coronavirus called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). COVID-19 has spread rapidly worldwide and has been shown to have a wide spectrum of severity. COVID-19 has become a public health emergency of relevant international concern, and it was declared a pandemic by the World Health Organization on 11 March, 2020. SARS-CoV-2 infection in severe cases involves the host response as an important contributor to the disease process and tissue damage, mainly due to dysregulated and excessive innate immune responses. The primary immune response leads to viral clearance in the majority of cases. However, in a subgroup of patients, the secondary immune response may be exaggerated, leading to inflammatory-induced lung injury and other complications including pneumonitis, acute respiratory distress syndrome, respiratory failure, shock, organ failure, and potentially death. Several cutaneous immune-mediated diseases, including psoriasis, atopic dermatitis, and hidradenitis suppurativa, are therapeutically managed with biologic and non-biologic immunosuppressive and immunomodulatory drugs. The outbreak of COVID-19 affects the management of these chronic conditions, not only for those who are already receiving treatment but also for those who are about to start a new treatment to control their disease. In this article, the management of cutaneous immune-mediated diseases during the COVID-19 pandemic is discussed.

negative: Topological data analysis to model the shape of immune responses during co-infections Co-infections by multiple pathogens have important implications in many aspects of health, epidemiology and evolution. However, how to disentangle the non-linear dynamics of the immune response when two infections take place at the same time is largely unexplored. Using data sets of the immune response during influenza-pneumococcal co-infection in mice, we employ here topological data analysis to simplify and visualise high dimensional data sets. We identified persistent shapes of the simplicial complexes of the data in the three infection scenarios: single viral infection, single bacterial infection, and co-infection. The immune response was found to be distinct for each of the infection scenarios and we uncovered that the immune response during the co-infection has three phases and two transition points. During the first phase, its dynamics is inherited from its response to the primary (viral) infection. The immune response has an early shift (few hours post co-infection) and then modulates its response to react against the secondary (bacterial) infection. Between 18 and 26 h post co-infection the nature of the immune response changes again and does no longer resembles either of the single infection scenarios.

negative: Estimating required lockdown cycles before immunity to SARS-CoV-2: Model-based analyses of susceptible population sizes, S0, in seven European countries including the UK and Ireland Background: Following stringent social distancing measures, some European countries are beginning to report a slowed or negative rate of growth of daily case numbers testing positive for the novel coronavirus. The notion that the first wave of infection is close to its peak begs the question of whether future peaks or second waves are likely. We sought to determine the current size of the effective (i.e. susceptible) population for seven European countries - to estimate immunity levels following this first wave. We compare these numbers to the total population sizes of these countries, in order to investigate the potential for future peaks. Methods: We used Bayesian model inversion to estimate epidemic parameters from the reported case and death rates from seven countries using data from late January 2020 to April 5th 2020. Two distinct generative model types were employed: first a continuous time dynamical-systems implementation of a Susceptible-Exposed-Infectious-Recovered (SEIR) model and second: a partially observable Markov Decision Process (MDP) or hidden Markov model (HMM) implementation of an SEIR model. Both models parameterise the size of the initial susceptible population (S0), as well as epidemic parameters. Parameter estimation (data fitting) was performed using a standard Bayesian scheme (variational Laplace) designed to allow for latent unobservable states and uncertainty in model parameters. Results: Both models recapitulated the dynamics of transmissions and disease as given by case and death rates. The peaks of the current waves were predicted to be in the past for four countries (Italy, Spain, Germany and Switzerland) and to emerge in 0.5-2 weeks in Ireland and 1-3 weeks in the UK. For France one model estimated the peak within the past week and the other in the future in two weeks. Crucially, Maximum a posteriori (MAP) estimates of S0 for each country indicated effective population sizes of below 20% (of total population size), under both the continuous time and HMM models. Using for all countries, with a Bayesian weighted average across all seven countries and both models, we estimated that 6.4% of the total population would be immune. From the two models the maximum percentage of the effective population was estimated at 19.6% of the total population for the UK, 16.7% for Ireland, 11.4% for Italy, 12.8% for Spain, 18.8% for France, 4.7% for Germany and 12.9% for Switzerland. Conclusion: Our results indicate that after the current wave, a large proportion of the total population will remain without immunity. This suggests that in the absence of strong seasonal effects, new medications or more comprehensive contact tracing, a further set of epidemic waves in different geographic centres are likely. These findings may have implications for exit strategies from any lockdown stage.

negative: Coronavirus infections and immune responses Coronaviruses (CoVs) are by far the largest group of known positive‐sense RNA viruses having an extensive range of natural hosts. In the past few decades, newly evolved Coronaviruses have posed a global threat to public health. The immune response is essential to control and eliminate CoV infections, however, maladjusted immune responses may result in immunopathology and impaired pulmonary gas exchange. Gaining a deeper understanding of the interaction between Coronaviruses and the innate immune systems of the hosts may shed light on the development and persistence of inflammation in the lungs and hopefully can reduce the risk of lung inflammation caused by CoVs. In this review, we provide an update on CoV infections and relevant diseases, particularly the host defense against CoV‐induced inflammation of lung tissue, as well as the role of the innate immune system in the pathogenesis and clinical treatment.

negative: Healthcare impact of COVID-19 epidemic in India: A stochastic mathematical model Abstract Background In India, the SARS-CoV-2 COVID-19 epidemic has grown to 1251 cases and 32 deaths as on 30 Mar 2020. The healthcare impact of the epidemic in India was studied using a stochastic mathematical model. Methods A compartmental SEIR model was developed, in which the flow of individuals through compartments is modeled using a set of differential equations. Different scenarios were modeled with 1000 runs of Monte Carlo simulation each using MATLAB. Hospitalization, intensive care unit (ICU) requirements, and deaths were modeled on SimVoi software. The impact of nonpharmacological interventions (NPIs) including social distancing and lockdown on checking the epidemic was estimated. Results Uninterrupted epidemic in India would have resulted in more than 364 million cases and 1.56 million deaths with peak by mid-July. As per the model, at current growth rate of 1.15, India is likely to reach approximately 3 million cases by 25 May, implying 125,455 (±18,034) hospitalizations, 26,130 (±3298) ICU admissions, and 13,447 (±1819) deaths. This would overwhelm India's healthcare system. The model shows that with immediate institution of NPIs, the epidemic might still be checked by mid-April 2020. It would then result in 241,974 (±33,735) total infections, 10,214 (±1649) hospitalizations, 2121 (±334) ICU admissions, and 1081 (±169) deaths. Conclusion At the current growth rate of epidemic, India's healthcare resources will be overwhelmed by the end of May. With the immediate institution of NPIs, total cases, hospitalizations, ICU requirements, and deaths can be reduced by almost 90%.

negative: Can the enteric nervous system be an alternative entrance door in SARS-CoV2 neuroinvasion?

negative: The Human Antibody Response to Dengue Virus Infection Dengue viruses (DENV) are the causative agents of dengue fever (DF) and dengue hemorrhagic fever (DHF). Here we review the current state of knowledge about the human antibody response to dengue and identify important knowledge gaps. A large body of work has demonstrated that antibodies can neutralize or enhance DENV infection. Investigators have mainly used mouse monoclonal antibodies (MAbs) to study interactions between DENV and antibodies. These studies indicate that antibody neutralization of DENVs is a “multi-hit” phenomenon that requires the binding of multiple antibodies to neutralize a virion. The most potently neutralizing mouse MAbs bind to surface exposed epitopes on domain III of the dengue envelope (E) protein. One challenge facing the dengue field now is to extend these studies with mouse MAbs to better understand the human antibody response. The human antibody response is complex as it involves a polyclonal response to primary and secondary infections with 4 different DENV serotypes. Here we review studies conducted with immune sera and MAbs isolated from people exposed to dengue infections. Most dengue-specific antibodies in human immune sera are weakly neutralizing and bind to multiple DENV serotypes. The human antibodies that potently and type specifically neutralize DENV represent a small fraction of the total DENV-specific antibody response. Moreover, these neutralizing antibodies appear to bind to novel epitopes including complex, quaternary epitopes that are only preserved on the intact virion. These studies establish that human and mouse antibodies recognize distinct epitopes on the dengue virion. The leading theory proposed to explain the increased risk of severe disease in secondary cases is antibody dependent enhancement (ADE), which postulates that weakly neutralizing antibodies from the first infection bind to the second serotype and enhance infection of FcγR bearing myeloid cells such as monocytes and macrophages. Here we review results from human, animal and cell culture studies relevant to the ADE hypothesis. By understanding how human antibodies neutralize or enhance DENV, it will be possible to better evaluate existing vaccines and develop the next generation of novel vaccines.

negative: Chapter 48 Mucosal Vaccine Development for Veterinary and Aquatic Diseases Abstract Because most pathogens and food antigens enter the host via the mucosal surfaces, effective mucosal immunity is critical for maintaining homeostasis through immune regulation, tolerance, and induction of effective immune responses when needed. Thus the mucosa-associated lymphoid tissues represent an important target for vaccination. Indeed, more than 20 years of research have clearly demonstrated the benefits of mucosal vaccination versus systemic vaccination. Such benefits include local induction of secretory immunoglobulin A (SIgA) as well as activation and maturation of mucosal dendritic cells, homing of effector cells to the mucosal surfaces, expression of specific host defense peptides, and other innate effector molecules. In addition, mucosal vaccination offers the opportunity to induce colostral and lactogenic immunity during pregnancy and the possibility of avoiding neutralization of early life vaccines by maternal antibodies, both of which are critical for protecting the most susceptible from infectious diseases. Moreover, mucosal administration offers the advantage of inducing both effective systemic immunity and mucosal immunity, enhancing vaccine efficacy and providing improved protection. A number of animal vaccines are already administered via the mucosal surfaces, with many more to come over the next few years. It is gratifying to see that veterinary vaccine development has yet again taken a leadership role in exploring innovative approaches and technologies to mucosal vaccination. For the veterinary field, considerations for mucosal vaccine development and use necessarily include costs (often pennies per dose), mass delivery that preferably avoids animal restraint, and economic and trade considerations. In this chapter, we provide an overview of some of the existing vaccine technologies and discuss their advantages and disadvantages.

negative: Kitchen Spectroscopy: Shining a (UV) Light on Everyday Objects Fluorescent objects often lead to a sense of joy and intrigue. While the current COVID-19 pandemic limits the synthesis of “glowy things” like quantum dots, many household objects fluoresce, providing an opportunity to brighten your day while learning fundamental chemistry.

negative: Emerging Viruses Emerging viruses are viruses that appear suddenly in the human population. These are viruses to which man has no history of exposure and thus no or limited immunity; they are not new evolutionary creations, but are viruses than man meets due to environmental changes, such as deforestation, entering into new habitats, or viruses that are transmitted from one species of animal to humans. Most of these viruses are terrifying, and cause hemorrhagic fever, a complete destruction of the circulation system; they include Lassa fever, Nipah virus, Ebola, HIV, Severe acute respiratory syndrome (SARS), and, recently, Middle East respiratory syndrome (MERS), which is the latest in a series of “new” respiratory viruses infecting man. It is possible that unknown emerging viruses are the cause of death, often listed as “death due to an unknown cause,” as in the retrospective cases of HIV. Emerging viruses might also include poliovirus and influenza, since their introduction into the human population is (was) often sudden and due to changes in the environment or due to contact with other animal species. For examples, polio was a result of changes in sanitation in the countries of North America and Western Europe, and influenza is constantly jumping from aquatic birds to man and other animal species where genomic reassortment occurs.

negative: Current treatment options and the role of peptides as potential therapeutic components for Middle East Respiratory Syndrome (MERS): A review Abstract Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is a highly pathogenic respiratory virus with mechanisms that may be driven by innate immune responses. Despite the effort of scientific studies related to this virus, Middle East Respiratory Syndrome (MERS) is still a public health concern. MERS-CoV infection has a high mortality rate, and to date, no therapeutic or vaccine has been discovered, that is effective in treating or preventing the disease. In this review, we summarize our understanding of the molecular and biological events of compounds acting as MERS-CoV inhibitors, the outcomes of existing therapeutic options and the various drugs undergoing clinical trials. Currently, several therapeutic options have been employed, such as convalescent plasma (CP), intravenous immunoglobulin (IVIG), monoclonal antibodies and repurposing of existing clinically approved drugs. However, these therapeutic options have drawbacks, thus the need for an alternative approach. The requirement for effective therapeutic treatment has brought the necessity for additional MERS treatments. We suggest that antimicrobial peptides (AMPs) may be used as alternative therapeutic agents against MERS-CoV infection. In addition, we propose the feasibility of developing effective agents by repurposing the existing and clinically approved anti-coronavirus and anti-viral peptide drugs.

negative: Probiotics and COVID‐19: is there any link? Understanding mechanisms of the novel SARS‐CoV2 infection and progression, can provide potential novel targets for prevention and/or treatment. This could be achieved via the inhibition of viral entry and/or replication, or by suppression the immunologic response that is provoked by the infection (known as the cytokine storm). Probiotics are defined as “live microorganisms that, when administered in adequate amounts, confer a health benefit on the host”. There is scarcity of evidence about the relationship between COVID‐19 and gut microbiota. So, whether or not these supplements can prevent or ameliorate COVID‐19 associated symptoms is not fully understood. The aim of this paper is to provide an indirect evidence about the utility of probiotics in combating COVID‐19 or its associated symptoms, through the review of its antiviral and anti‐inflammatory properties in vitro, animal models, and human trials.

negative: Molecular basis of genetic variation of viruses: error-prone replication Genetic variation is a necessity of all biological systems. Viruses use all known mechanisms of variation; mutation, several forms of recombination, and segment reassortment in the case of viruses with a segmented genome. These processes are intimately connected with the replicative machineries of viruses, as well as with fundamental physical-chemical properties of nucleotides when acting as template or substrate residues. Recombination has been viewed as a means to rescue viable genomes from unfit parents or to produce large modifications for the exploration of phenotypic novelty. All types of genetic variation can act conjointly as blind processes to provide the raw materials for adaptation to the changing environments in which viruses must replicate. A distinction is made between mechanistically unavoidable and evolutionarily relevant mutation and recombination.

negative: Characterization of peritoneal cells from cats with experimentally-induced feline infectious peritonitis (FIP) using RNA-seq Laboratory cats were infected with a serotype I cat-passaged field strain of FIP virus (FIPV) and peritoneal cells harvested 2–3 weeks later at onset of lymphopenia, fever and serositis. Comparison peritoneal cells were collected from four healthy laboratory cats by peritoneal lavage and macrophages predominated in both populations. Differential mRNA expression analysis identified 5621 genes as deregulated in peritoneal cells from FIPV infected versus normal cats; 956 genes showed > 2.0 Log(2) Fold Change (Log(2)FC) and 1589 genes showed < −2.0 Log(2)FC. Eighteen significantly upregulated pathways were identified by InnateDB enrichment analysis. These pathways involved apoptosis, cytokine–cytokine receptor interaction, pathogen recognition, Jak-STAT signaling, NK cell mediated cytotoxicity, several chronic infectious diseases, graft versus host disease, allograft rejection and certain autoimmune disorders. Infected peritoneal macrophages were activated M1 type based on pattern of RNA expression. Apoptosis was found to involve large virus-laden peritoneal macrophages more than less mature macrophages, suggesting that macrophage death played a role in virus dissemination. Gene transcripts for MHC I but not II receptors were upregulated, while mRNA for receptors commonly associated with virus attachment and identified in other coronaviruses were either not detected (APN, L-SIGN), not deregulated (DDP-4) or down-regulated (DC-SIGN). However, the mRNA for FcγRIIIA (CD16A/ADCC receptor) was significantly upregulated, supporting entry of virus as an immune complex. Analysis of KEGG associated gene transcripts indicated that Th1 polarization overshadowed Th2 polarization, but the addition of relevant B cell associated genes previously linked to FIP macrophages tended to alter this perception.

negative: Antibodies and vaccines against Middle East respiratory syndrome coronavirus The Middle East respiratory syndrome coronavirus (MERS-CoV) has spread through 27 countries and infected more than 2,200 people since its first outbreak in Saudi Arabia in 2012. The high fatality rate (35.4%) of this novel coronavirus and its persistent wide spread infectiousness in animal reservoirs have generated tremendous global public health concern. However, no licensed therapeutic agents or vaccines against MERS-CoV are currently available and only a limited few have entered clinical trials. Among all the potential targets of MERS-CoV, the spike glycoprotein (S) has been the most well-studied due to its critical role in mediating viral entry and in inducing a protective antibody response in infected individuals. The most notable studies include the recent discoveries of monoclonal antibodies and development of candidate vaccines against the S glycoprotein. Structural characterization of MERS-CoV S protein bound with these monoclonal antibodies has provided insights into the mechanisms of humoral immune responses against MERS-CoV infection. The current review aims to highlight these developments and discuss possible hurdles and strategies to translate these discoveries into ultimate medical interventions against MERS-CoV infection.

negative: Antibióticos en las infecciones respiratorias El correcto tratamiento de las infecciones respiratorias representa un reto continuo para el médico de atención primaria. La mayor parte de las veces el tratamiento es empírico, debiendo combinar diferentes aspectos, como un diagnóstico correcto, microorganismos causales más probables, espectro de acción del antibiótico elegido, aumento de resistencias a antibióticos, aparición de nuevos fármacos, expectativas de adecuado cumplimiento y, por último, valorar la relación coste-efectividad. En este artículo se hace una revisión del tratamiento antibiótico de las infecciones respiratorias más frecuentes, como otitis, rinosinusitis, faringoamigdalitis, neumonía extrahospitalaria y reagudización de EPOC.

negative: Severe acute respiratory syndrome-associated coronavirus vaccines formulated with delta inulin adjuvants provide enhanced protection while ameliorating lung eosinophilic immunopathology. UNLABELLED Although the severe acute respiratory syndrome-associated coronavirus (SARS-CoV) epidemic was controlled by nonvaccine measures, coronaviruses remain a major threat to human health. The design of optimal coronavirus vaccines therefore remains a priority. Such vaccines present major challenges: coronavirus immunity often wanes rapidly, individuals needing to be protected include the elderly, and vaccines may exacerbate rather than prevent coronavirus lung immunopathology. To address these issues, we compared in a murine model a range of recombinant spike protein or inactivated whole-virus vaccine candidates alone or adjuvanted with either alum, CpG, or Advax, a new delta inulin-based polysaccharide adjuvant. While all vaccines protected against lethal infection, addition of adjuvant significantly increased serum neutralizing-antibody titers and reduced lung virus titers on day 3 postchallenge. Whereas unadjuvanted or alum-formulated vaccines were associated with significantly increased lung eosinophilic immunopathology on day 6 postchallenge, this was not seen in mice immunized with vaccines formulated with delta inulin adjuvant. Protection against eosinophilic immunopathology by vaccines containing delta inulin adjuvants correlated better with enhanced T-cell gamma interferon (IFN-γ) recall responses rather than reduced interleukin-4 (IL-4) responses, suggesting that immunopathology predominantly reflects an inadequate vaccine-induced Th1 response. This study highlights the critical importance for development of effective and safe coronavirus vaccines of selection of adjuvants based on the ability to induce durable IFN-γ responses. IMPORTANCE Coronaviruses such as SARS-CoV and Middle East respiratory syndrome-associated coronavirus (MERS-CoV) cause high case fatality rates and remain major human public health threats, creating a need for effective vaccines. While coronavirus antigens that induce protective neutralizing antibodies have been identified, coronavirus vaccines present a unique problem in that immunized individuals when infected by virus can develop lung eosinophilic pathology, a problem that is further exacerbated by the formulation of SARS-CoV vaccines with alum adjuvants. This study shows that formulation of SARS-CoV spike protein or inactivated whole-virus vaccines with novel delta inulin-based polysaccharide adjuvants enhances neutralizing-antibody titers and protection against clinical disease but at the same time also protects against development of lung eosinophilic immunopathology. It also shows that immunity achieved with delta inulin adjuvants is long-lived, thereby overcoming the natural tendency for rapidly waning coronavirus immunity. Thus, delta inulin adjuvants may offer a unique ability to develop safer and more effective coronavirus vaccines.

negative: Clinical Implications of SARS-CoV-2 Interaction With Renin Angiotensin System: JACC Review Topic of the Week Severe acute respiratory-syndrome coronavirus-2 (SARS-CoV-2) host cell infection is mediated by binding to angiotensin-converting enzyme 2 (ACE2). Systemic dysregulation observed in SARS-CoV was previously postulated to be due to ACE2/angiotensin 1-7 (Ang1-7)/Mas axis downregulation; increased ACE2 activity was shown to mediate disease protection. Because angiotensin II receptor blockers, ACE inhibitors, and mineralocorticoid receptor antagonists increase ACE2 receptor expression, it has been tacitly believed that the use of these agents may facilitate viral disease; thus, they should not be used in high-risk patients with cardiovascular disease. Based on the anti-inflammatory benefits of the upregulation of the ACE2/Ang1-7/Mas axis and previously demonstrated benefits of lung function improvement in SARS-CoV infections, it has been hypothesized that the benefits of treatment with renin-angiotensin system inhibitors in SARS-CoV-2 may outweigh the risks and at the very least should not be withheld.

negative: The Cellular and Physiological Basis for Lung Repair and Regeneration: Past, Present, and Future The respiratory system, which includes the trachea, airways, and distal alveoli, is a complex multi-cellular organ that intimately links with the cardiovascular system to accomplish gas exchange. In this review and as members of the NIH/NHLBI-supported Progenitor Cell Translational Consortium, we discuss key aspects of lung repair and regeneration. We focus on the cellular compositions within functional niches, cell-cell signaling in homeostatic health, the responses to injury, and new methods to study lung repair and regeneration. We also provide future directions for an improved understanding of the cell biology of the respiratory system, as well as new therapeutic avenues.

negative: Obstetric Management of COVID-19 in Pregnant Women The 2019 novel coronavirus disease (COVID-19), which is caused by the novel beta coronavirus, SARS-CoV-2, is currently prevalent all over the world, causing thousands of deaths with relatively high virulence. Like two other notable beta coronaviruses, severe acute respiratory syndrome coronavirus-1 (SARS-CoV-1) and Middle East respiratory syndrome coronavirus (MERS-CoV), SARS-CoV-2 can lead to severe contagious respiratory disease. Due to impaired cellular immunity and physiological changes, pregnant women are susceptible to respiratory disease and are more likely to develop severe pneumonia. Given the prevalence of COVID-19, it is speculated that some pregnant women have already been infected. However, limited data are available for the clinical course and management of COVID-19 in pregnancy. Therefore, we conducted this review to identify strategies for the obstetric management of COVID-19. We compared the clinical course and outcomes of COVID-19, SARS, and MERS in pregnancy and discussed several drugs for the treatment of COVID-19 in pregnancy.

negative: Tailoring Subunit Vaccine Immunity with Adjuvant Combinations and Delivery Routes Using the Middle East Respiratory Coronavirus (MERS-CoV) Receptor-Binding Domain as an Antigen The development of an effective vaccine is critical for prevention of a Middle East respiratory syndrome coronavirus (MERS-CoV) pandemic. Some studies have indicated the receptor-binding domain (RBD) protein of MERS-CoV spike (S) is a good candidate antigen for a MERS-CoV subunit vaccine. However, highly purified proteins are typically not inherently immunogenic. We hypothesised that humoral and cell-mediated immunity would be improved with a modification of the vaccination regimen. Therefore, the immunogenicity of a novel MERS-CoV RBD-based subunit vaccine was tested in mice using different adjuvant formulations and delivery routes. Different vaccination regimens were compared in BALB/c mice immunized 3 times intramuscularly (i.m.) with a vaccine containing 10 µg of recombinant MERS-CoV RBD in combination with either aluminium hydroxide (alum) alone, alum and polyriboinosinic acid (poly I:C) or alum and cysteine-phosphate-guanine (CpG) oligodeoxynucleotides (ODN). The immune responses of mice vaccinated with RBD, incomplete Freund’s adjuvant (IFA) and CpG ODN by a subcutaneous (s.c.) route were also investigated. We evaluated the induction of RBD-specific humoral immunity (total IgG and neutralizing antibodies) and cellular immunity (ELISpot assay for IFN-γ spot-forming cells and splenocyte cytokine production). Our findings indicated that the combination of alum and CpG ODN optimized the development of RBD-specific humoral and cellular immunity following subunit vaccination. Interestingly, robust RBD-specific antibody and T-cell responses were induced in mice immunized with the rRBD protein in combination with IFA and CpG ODN, but low level of neutralizing antibodies were elicited. Our data suggest that murine immunity following subunit vaccination can be tailored using adjuvant combinations and delivery routes. The vaccination regimen used in this study is promising and could improve the protection offered by the MERS-CoV subunit vaccine by eliciting effective humoral and cellular immune responses.

negative: First genome sequences of buffalo coronavirus from water buffaloes in Bangladesh We report the complete genome sequences of a buffalo coronavirus (BufCoV HKU26) detected from the faecal samples of two domestic water buffaloes (Bubalus bubalis) in Bangladesh. They possessed 98–99% nucleotide identities to bovine coronavirus (BCoV) genomes, supporting BufCoV HKU26 as a member of Betacoronavirus 1. Nevertheless, BufCoV HKU26 possessed distinct accessory proteins between spike and envelope compared to BCoV. Sugar-binding residues in the N-terminal domain of S protein in BCoV are conserved in BufCoV HKU26.

negative: Revisión Narrativa Sobre La Respuesta Inmunitaria Frente A Coronavirus: Descripción General, Aplicabilidad Para Sars-Cov2 E Implicaciones Terapéuticas Abstract The new coronavirus (SARS-CoV2) that causes a severe acute respiratory syndrome emerged in Wuhan, China, in December 2019. It produces the aforementioned disease due to coronavirus 2019 (COVID-19), and has led to a declaration of a world public health emergency by the World Health Organisation. This new SARS-CoV2 virus could share characteristics and an immune response similar to those described for other coronavirus. Given its activity on the interferon pathway, and the manner in which it dysregulates innate immunity, the use of treatments directed at modulating or containing this could be of interest. A narrative review was made of the current evidence about immunity against coronavirus and it applicability to SARS-CoV2. The physiopathogenesis is also described, along with the underlying leucocyte activity, with the intention of clarifying the possible usefulness of inflammatory biomarkers and the development of personalised treatments.

negative: Funding of drugs: do vaccines warrant a different approach? Summary Vaccines have features that require special consideration when assessing their cost-effectiveness. These features are related to herd immunity, quality-of-life losses in young children, parental care and work loss, time preference, uncertainty, eradication, macroeconomics, and tiered pricing. Advisory committees on public funding for vaccines, or for pharmaceuticals in general, should be knowledgable about these special features. We discuss key issues and difficulties in decision making for vaccines against rotavirus, human papillomavirus, varicella-zoster virus, influenza virus, and Streptococcus pneumoniae. We argue that guidelines for economic evaluation should be reconsidered generally to recommend (1) modelling options for the assessment of interventions against infectious diseases; (2) a wider perspective to account for impacts on third parties, if relevant; (3) a wider scope of costs than health-care system costs alone, if appropriate; and (4) alternative discounting techniques to explore social time preference over long periods.

negative: Tibialis anterior muscle fascicle dynamics adequately represent postural sway during standing balance. To maintain a stable, upright posture, the central nervous system (CNS) must integrate sensory information from multiple sources and subsequently generate corrective torque about the ankle joint. Although proprioceptive information from the muscles that cross this joint has been shown to be vital in this process, the specific source of this information remains questionable. Recent research has been focused on the potential role of tibialis anterior (TA) muscle during standing, largely due to the lack of modulation of its activity throughout the sway cycle. Ten young, healthy subjects were asked to stand normally under varying conditions, for periods of 60 s. During these trials, intramuscular electromyographic (EMG) activity and the fascicle length of three distinct anatomical regions of TA were sampled synchronously with kinematic data regarding sway position. In the quiet standing conditions, TA muscle activity was unmodulated and fascicle length changes in each region were tightly coupled with changes in sway position. In the active sway condition, more EMG activity was observed in TA and the fascicle length changes were decoupled from sway position. No regional specific differences in correlation values were observed, contrasting previous observations. The ability of the fascicles to follow sway position builds upon the suggestion that TA is well placed to provide accurate, straightforward sensory information to the CNS. As previously suggested, through reciprocal inhibition, afferent information from TA could help to regulate plantar flexor torque at relevant phases of the sway cycle. The proprioceptive role of TA appears to become complicated during more challenging conditions.

negative: Tetracyclines: a pleitropic family of compounds with promising therapeutic properties. Review of the literature. There must be something unique about a class of drugs (discovered and developed in the mid-1940s) where there are more than 130 ongoing clinical trials currently listed. Tetracyclines were developed as a result of the screening of soil samples for antibiotic organisms. The first of these compounds chlortetracycline was introduced in 1948. Soon after their development tetracyclines were found to be highly effective against various pathogens including rickettsiae, Gram-positive, and Gram-negative bacteria, thus, becoming a class of broad-spectrum antibiotics. The mechanism of action of tetracyclines is thought to be related to the inhibition of protein synthesis by binding to the 30S bacterial ribosome. Tetracyclines are also an effective anti-malarial drug. Over time, many other "protective" actions have been described for tetracyclines. Minocycline, which can readily cross cell membranes, is known to be a potent anti-apoptotic agent. Its mechanism of action appears to relate to specific effects exerted on apoptosis signaling pathways. Another tetracycline, doxycycline is known to exert antiprotease activities. Doxycycline can inhibit matrix metalloproteinases, which contribute to tissue destruction activities in diseases such as gingivitis. A large body of literature has provided additional evidence for the "beneficial" actions of tetracyclines, including their ability to act as oxygen radical scavengers and anti-inflammatory agents. This increasing volume of published work and ongoing clinical trials supports the notion that a more systematic examination of their possible therapeutic uses is warranted. This review provides a summary of tetracycline's multiple mechanisms of action and while using the effects on the heart as an example, this review also notes their potential to benefit patients suffering from various pathologies such as cancer, Rosacea, and Parkinson's disease.

negative: International Committee of the Red Cross (ICRC): General guidance for the management of the dead related to COVID-19 Abstract Based on its forensic capacity and experience gained worldwide from the management of the dead in emergencies, including epidemics, the International Committee of the Red Cross has been asked by the authorities and other relevant stakeholders in some of its operational contexts to advise on the management of the dead from COVID-19 infection, for which it has prepared the following guidance. This includes advice on the handling of COVID-19 fatalities and a set of considerations for managers faced with the need to plan for adequately responding to a possible surge in fatalities caused by COVID-19.

negative: Lack of patent liver autoimmunity after breakage of tolerance in a mouse model We report in this work that a cellular and humoral autoreactive response can be induced against liver‐specific self‐determinants by repeated immunization with a chimeric tissue‐specific self‐antigen carrying a heterologous T(h) epitope. Epitope spreading rendering the autoimmune reaction independent of the presence of the cognate heterologous help is also demonstrated. Although neutrophil infiltrates can be demonstrated in the livers of treated mice, no clinical sign of organ damage is observed. These findings suggest that breakage of tolerance by this means leads the process only up to the next checkpoint in the progression of autoimmune disease and that further events are required to precipitate functional organ impairment.

negative: T cell responses are required for protection from clinical disease and for virus clearance in severe acute respiratory syndrome coronavirus-infected mice. A dysregulated innate immune response and exuberant cytokine/chemokine expression are believed to be critical factors in the pathogenesis of severe acute respiratory syndrome (SARS), caused by a coronavirus (SARS-CoV). However, we recently showed that inefficient immune activation and a poor virus-specific T cell response underlie severe disease in SARS-CoV-infected mice. Here, we extend these results to show that virus-specific T cells, in the absence of activation of the innate immune response, were sufficient to significantly enhance survival and diminish clinical disease. We demonstrated that T cells are responsible for virus clearance, as intravenous adoptive transfer of SARS-CoV-immune splenocytes or in vitro-generated T cells to SCID or BALB/c mice enhanced survival and reduced virus titers in the lung. Enhancement of the number of virus-specific CD8 T cells by immunization with SARS-CoV peptide-pulsed dendritic cells also resulted in a robust T cell response, earlier virus clearance, and increased survival. These studies are the first to show that T cells play a crucial role in SARS-CoV clearance and that a suboptimal T cell response contributes to the pathological changes observed in SARS. They also provide a new approach to SARS vaccine design.

negative: Vaccines against Middle East respiratory syndrome coronavirus for humans and camels Middle East respiratory syndrome coronavirus (MERS‐CoV) is caused by a novel betacoronavirus that was isolated in late 2012 in Saudi Arabia. The viral infections have been reported in more than 1700 humans, ranging from asymptomatic or mild cases to severe pneumonia with a mortality rate of 40%. It is well documented now that dromedary camels contract the infection and shed the virus without notable symptoms, and such animals had been infected by at least the early 1980s. The mechanism of camel to human transmission is still not clear, but several primary cases have been associated with camel contact. There is no approved antiviral drug or vaccine against MERS‐CoV despite the active research in this area. Vaccine candidates have been developed using various platforms and regimens and have been tested in several animal models. Here, this article reviews the published studies on MERS‐CoV vaccines with more focus on vaccines tested in large animals, including camels. It is foreseeable that the 1‐health approach could be the best way of tackling the MERS‐CoV endemic in the Arabian Peninsula, by using the mass vaccination of camels in the affected areas to block camel to human transmission. Camel vaccines can be developed in a faster time with fewer regulations and lower costs and could clear this virus from the Arabian Peninsula if accompanied by efficient public health measures.

negative: Positive Selection of a Serine Residue in Bat IRF3 Confers Enhanced Antiviral Protection Compared with other mammals, bats harbor more zoonotic viruses per species and do not demonstrate signs of disease on infection with these viruses. To counteract infections with viruses, bats have evolved enhanced mechanisms to limit virus replication and immunopathology. However, molecular and cellular drivers of antiviral responses in bats largely remain an enigma. In this study, we demonstrate that a serine residue in IRF3 is positively selected for in multiple bat species. IRF3 is a central regulator of innate antiviral responses in mammals. Replacing the serine residue in bat IRF3 with the human leucine residue decreased antiviral protection in bat cells, whereas the addition of this serine residue in human IRF3 significantly enhanced antiviral protection in human cells. Our study provides genetic and functional evidence for enhanced IRF3-mediated antiviral responses in bats and adds support to speculations that bats have positively selected for multiple adaptations in their antiviral immune responses.

negative: Infectivity and cross-immunity studies of Theileria lestoquardi and Theileria annulata in sheep and cattle: I. In vivo responses In a series of experiments, sporozoite stabilates of a Theileria lestoquardi (Lahr) and a T. annulata (Ankara) stock prepared from Hyalomma anatolicum anatolicum ticks, were used to examine the infectivity of both parasite species for sheep and cattle and to study the development of cross-immunity between these parasite species. In the first experiment sheep and cattle were inoculated with T. lestoquardi sporozoites. Surviving animals and naive sheep and cattle were, in the second experiment, inoculated with T. annulata. In the third experiment, naive sheep and sheep previously infected with T. annulata, were inoculated with T. lestoquardi. The following responses to inoculations were monitored: clinical and haematological signs of infection, appearance of parasitic stages of the parasites in lymph node biopsies and in peripheral blood and serological response to T. lestoquardi and T. annulata schizont antigens. While T. lestoquardi readily infected sheep and caused severe disease, it did not infect cattle. On the other hand, T. annulata infected both cattle and sheep. However, whereas cattle became severely affected, infected sheep showed mild clinical symptoms only and piroplasms did not develop. Despite their different behaviour in the host species examined, cross-immunity studies suggested that the parasite species are very closely related. Experiments in sheep indicated that T. lestoquardi infection protected against subsequent T. annulata infection. On the other hand, recovery from T. annulata infection did not prevent infection by sporozoites of T. lestoquardi, resulting in the establishment of schizonts and their subsequent development into piroplasms, although it protected against the major clinical effects of T. lestoquardi infection.

negative: Controlled, double-blind, randomized trial to assess the efficacy and safety of hydroxychloroquine chemoprophylaxis in SARS CoV2 infection in healthcare personnel in the hospital setting: A structured summary of a study protocol for a randomised controlled trial BACKGROUND: SARS-CoV-2 infection presents a high transmission in the group of health professionals in Spain (12-15% infected). Currently there is no accepted chemoprophylaxis but hydroxychloroquine (HDQ) is known to inhibit the coronavirus in vitro. Our hypothesis is that oral administration of hydroxychloroquine to healthcare professionals can reduce the incidence and prevalence of infection as well as its severity in this group. METHODS: Design: Prospective, single center, double blind, randomised, controlled trial (RCT). PARTICIPANTS: Adult health-care professionals (18-65 years) working in areas of high exposure and high risk of transmission of SARS-COV-2 (COVID areas, Intensive Care Unit -ICUs-, Emergency, Anesthesia and all those performing aerosol-generating procedures) will be included. Exclusion criteria include previous infection with SARS CoV2 (positive SARS-CoV-2 PCR or IgG serology), pregnancy or lactation, any contraindication to hydroxychloroquine or evidence of unstable or clinically significant systemic disease. INTERVENTIONS: Patients will be randomized (1:1) to receive once-daily oral Hydroxychloroquine 200mg for two months (HC group) or placebo (P group) in addition to the protective measures appropriate to the level of exposure established by the hospital. A serological evaluation will be carried out every 15 days with PCR in case of seroconversion, symptoms or risk exposure. Primary outcome is the percentage of subjects presenting infection (seroconversion and/or PCR +ve) by the SARS-Cov-2 virus during the observation period. Additionally, both the percentage of subjects in each group presenting Pneumonia with severity criteria (Curb 65 ≥2) and that of subjects requiring admission to ICU will be determined. DISCUSSION: While awaiting a vaccine, hygiene measures, social distancing and personal protective equipment are the only primary prophylaxis measures against SARS-CoV-2, but they have not been sufficient to protect our healthcare professionals. Some evidence of the in vitro efficacy of hydroxychloroquine against this virus is known, along with some clinical data that would support the study of this drug in the chemoprophylaxis of infection. However, there are still no data from controlled clinical trials in this regard. If our hypothesis is confirmed, hydroxychloroquine can help professionals fight this infection with more guarantees. PARTICIPANTS: This is a single-center study that will be carried out at the Marqués de Valdecilla University Hospital. 450 health professionals working at the Hospital Universitario Marqués de Valdecilla in areas of high exposure and high risk of transmission of SARS COV2 (COVID hospital areas, Intensive Care Unit, Emergency, Anesthesia and all those performing aerosol-generating procedures) will be included. INCLUSION CRITERIA: 1) Health professionals aged between 18 and 65 years (inclusive) at the time of the first screening visit; 2) They must provide signed written informed consent and agree to comply with the study protocol; 3) Active work in high exposure areas during the last two weeks and during the following weeks. EXCLUSION CRITERIA: 1) Previous infection with SARS CoV2 (positive coronavirus PCR or positive serology with SARS Cov2 negative PCR and absence of symptoms); 2) Current treatment with hydroxychloroquine or chloroquine; 3) Hypersensitivity, allergy or any contraindication for taking hydroxychloroquine, in the technical sheet; 4) Previous or current treatment with tamoxifen or raloxifene; 5) Previous eye disease, especially maculopathy; 6) Known heart failure (Grade III to IV of the New York Heart Association classification) or prolonged QTc; 7) Any type of cancer (except basal cell) in the last 5 years; 6) Refusal to give informed consent; 8) Evidence of any other unstable or clinically significant untreated immune, endocrine, hematological, gastrointestinal, neurological, neoplastic or psychiatric illness; 9) Antibodies positive for the human immunodeficiency virus; 10) Significant kidney or liver disease; 11) Pregnancy or lactation. INTERVENTION AND COMPARATOR: Two groups will be analyzed with a 1: 1 randomization rate. 1)Intervention: (n = 225): One 200 mg hydroxychloroquine sulfate coated tablet once daily for two months.2)Comparator (control group) (n = 225): One hydroxychloroquine placebo tablet (identical to that of the drug) once daily for two months MAIN OUTCOMES: The primary outcome of this study will be to evaluate: number and percentage of healthcare personnel presenting symptomatic and asymptomatic infection (see "Diagnosis of SARS CoV2 infection" below) by the SARS-Cov2 virus during the study observation period (8 weeks) in both treatment arms;number and percentage of healthcare personnel in each group presenting with Pneumonia with severity criteria (Curb 65 ≥2) and number and percentage of healthcare personnel requiring admission to the Intensive Care Unit (ICU) in both treatment arms. DIAGNOSIS OF SARS COV2 INFECTION: Determination of IgA, IgM and IgG type antibodies against SARS-CoV-2 using the Anti-SARS-CoV-2 ELISA kit (EUROIMMUN Medizinische Labordiagnostika AG, Germany) every two weeks. In cases of seroconversion, a SARS-CoV-2 PCR will be performed to rule out / confirm an active infection (RT-PCR in One Step: RT performed with mastermix (Takara) and IDT probes, following protocol published and validated by the CDC Evaluation of COVID-19 in case of SARS-CoV-2 infection RANDOMISATION: Participants will be allocated to intervention and comparator groups according to a balanced randomization scheme (1: 1). The assignment will be made through a computer-generated numeric sequence for all participants BLINDING (MASKING): Both participants and investigators responsible for recruiting and monitoring participants will be blind to the assigned arm. NUMBERS TO BE RANDOMISED (SAMPLE SIZE): Taking into account the current high prevalence of infection in healthcare personnel in Spain (up to 15%), to detect a difference equal to or greater than 8% in the percentage estimates through a two-tailed 95% CI, with a statistical power of 80% and a dropout rate of 5%, a total of 450 participants will need to be included (250 in each arm). TRIAL STATUS: The protocol approved by the health authorities in Spain (Spanish Agency for Medicines and Health Products "AEMPS") and the Ethics and Research Committee of Cantabria (CEIm Cantabria) corresponds to version 1.1 of April 2, 2020. Currently, recruitment has not yet started, with the start scheduled for the second week of May 2020. TRIAL REGISTRATION: Eudra CT number: 2020-001704-42 (Registered on 29 March 2020) FULL PROTOCOL: The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol. The study protocol has been reported in accordance with the Standard Protocol Items: Recommendations for Clinical Interventional Trials (SPIRIT) guidelines (Additional file 2).

negative: Global transmission network of SARS-CoV-2: from outbreak to pandemic BACKGROUND. The COVID-19 pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is straining health systems around the world. Although the Chinese government implemented a number of severe restrictions on people’s movement in an attempt to contain its local and international spread, the virus had already reached many areas of the world in part due to its potent transmissibility and the fact that a substantial fraction of infected individuals develop little or no symptoms at all. Following its emergence, the virus started to generate sustained transmission in neighboring countries in Asia, Western Europe, Australia, Canada and the United States, and finally in South America and Africa. As the virus continues its global spread, a clear and evidence-based understanding of properties and dynamics of the global transmission network of SARS-CoV-2 is essential to design and put in place efficient and globally coordinated interventions. METHODS. We employ molecular surveillance data of SARS-CoV-2 epidemics for inference and comprehensive analysis of its global transmission network before the pandemic declaration. Our goal was to characterize the spatial-temporal transmission pathways that led to the establishment of the pandemic. We exploited a network-based approach specifically tailored to emerging outbreak settings. Specifically, it traces the accumulation of mutations in viral genomic variants via mutation trees, which are then used to infer transmission networks, revealing an up-to-date picture of the spread of SARS-CoV-2 between and within countries and geographic regions. RESULTS AND CONCLUSIONS. The analysis suggest multiple introductions of SARS-CoV-2 into the majority of world regions by means of heterogeneous transmission pathways. The transmission network is scale-free, with a few genomic variants responsible for the majority of possible transmissions. The network structure is in line with the available temporal information represented by sample collection times and suggest the expected sampling time difference of few days between potential transmission pairs. The inferred network structural properties, transmission clusters and pathways and virus introduction routes emphasize the extent of the global epidemiological linkage and demonstrate the importance of internationally coordinated public health measures.

negative: Difficulties in demonstrating long term immunity in FeLV vaccinated cats due to increasing age-related resistance to infection BACKGROUND: Feline leukaemia virus (FeLV) is a pathogen causing fatal illness in cats worldwide, and as such there is a high demand for products to protect against disease. The duration of immunity provided by an inactivated FeLV vaccine, Versifel FeLV, when administered to cats of the target age was determined. Kittens received two vaccinations when aged 7 to 9 weeks old, and were subsequently challenged up to 36 months later with the FeLV-A Glasgow isolate. RESULTS: In all studies, all of the younger aged control kittens showed persistent FeLV p27 antigenaemia confirming that the challenge virus was severe and efficacious. In contrast, the control cats did not show the required level of persistent antigenaemia, with a maximum of 45% cats affected in the middle duration study and only 10% in the longer study. However, apart from one animal in the short duration study, all of the cats vaccinated with Versifel FeLV were negative for persistent antigenaemia and can be considered treatment successes. CONCLUSION: In conclusion, we have shown that although age-related resistance to infection with a virulent FeLV challenge is evident from as early as 10 months of age, vaccination with Versifel FeLV may aid in the protection of cats from FeLV related disease up to three years after primary vaccination as kittens.

negative: Importance of homo-dimerization of Fanconi-associated nuclease 1 in DNA flap cleavage Abstract Fanconi-associated nuclease 1 (FAN1) removes interstrand DNA crosslinks (ICLs) through its DNA flap endonuclease and exonuclease activities. Crystal structures of human and bacterial FAN1 bound to a DNA flap have been solved. The Pseudomonas aeruginosa bacterial FAN1 and human FAN1 (hFAN1) missing a flexible loop are monomeric, while intact hFAN1 is homo-dimeric in structure. Importantly, the monomeric and dimeric forms of FAN1 exhibit very different DNA binding modes. Here, we interrogate the functional differences between monomeric and dimeric forms of FAN1 and provide an explanation for the discrepancy in oligomeric state between the two hFAN1 structures. Specifically, we show that the flexible loop in question is needed for hFAN1 dimerization. While monomeric and dimeric bacterial or human FAN1 proteins cleave a short 5′ flap strand with similar efficiency, optimal cleavage of a long 5′ flap strand is contingent upon protein dimerization. Our study therefore furnishes biochemical evidence for a role of hFAN1 homodimerization in biological processes that involve 5′ DNA Flap cleavage.

negative: Cryo-EM structure of infectious bronchitis coronavirus spike protein reveals structural and functional evolution of coronavirus spike proteins As cell-invading molecular machinery, coronavirus spike proteins pose an evolutionary conundrum due to their high divergence. In this study, we determined the cryo-EM structure of avian infectious bronchitis coronavirus (IBV) spike protein from the γ-genus. The trimeric IBV spike ectodomain contains three receptor-binding S1 heads and a trimeric membrane-fusion S2 stalk. While IBV S2 is structurally similar to those from the other genera, IBV S1 possesses structural features that are unique to different other genera, thereby bridging these diverse spikes into an evolutionary spectrum. Specifically, among different genera, the two domains of S1, the N-terminal domain (S1-NTD) and C-terminal domain (S1-CTD), diverge from simpler tertiary structures and quaternary packing to more complex ones, leading to different functions of the spikes in receptor usage and membrane fusion. Based on the above structural and functional comparisons, we propose that the evolutionary spectrum of coronavirus spikes follows the order of α-, δ-, γ-, and β-genus. This study has provided insight into the evolutionary relationships among coronavirus spikes and deepened our understanding of their structural and functional diversity.

negative: In-silico approaches to detect inhibitors of the human severe acute respiratory syndrome coronavirus envelope protein ion channel Recent outbreak of Coronavirus disease (COVID-19) pandemic around the world is associated with ‘severe acute respiratory syndrome’ (SARS-CoV2) in humans. SARS-CoV2 is an enveloped virus and E proteins present in them are reported to form ion channels, which is mainly associated with pathogenesis. Thus, there is always a quest to inhibit these ion channels, which in turn may help in controlling diseases caused by SARS-CoV2 in humans. Considering this, in the present study, authors employed computational approaches for studying the structure as well as function of the human ‘SARS-CoV2 E’ protein as well as its interaction with various phytochemicals. Result obtained revealed that α-helix and loops present in this protein experience random movement under optimal condition, which in turn modulate ion channel activity; thereby aiding the pathogenesis caused via SARS-CoV2 in human and other vertebrates. However, after binding with Belachinal, Macaflavanone E, and Vibsanol B, the random motion of the human ‘SARS-CoV2 E’ protein gets reduced, this, in turn, inhibits the function of the ‘SARS-CoV2 E’ protein. It is pertinent to note that two amino acids, namely VAL25 and PHE26, play a key role while interacting with these three phytochemicals. As these three phytochemicals, namely, Belachinal, Macaflavanone E & Vibsanol B, have passed the ADMET (Absorption, Distribution, Metabolism, Excretion and Toxicity) property as well as ‘Lipinski’s Rule of 5s’, they may be utilized as drugs in controlling disease caused via SARS-COV2, after further investigation. Communicated by Ramaswamy H. Sarma

negative: ElaD, a Deubiquitinating Protease Expressed by E. coli BACKGROUND: Ubiquitin and ubiquitin-like proteins (Ubl) are designed to modify polypeptides in eukaryotes. Covalent binding of ubiquitin or Ubls to substrate proteins can be reversed by specific hydrolases. One particular set of cysteine proteases, the CE clan, which targets ubiquitin and Ubls, has homologs in eukaryotes, prokaryotes, and viruses. FINDINGS: We have cloned and analyzed the E. coli protein elaD, which is distantly related to eukaryotic CE clan members of the ULP/SENP protease family that are specific for SUMO and Nedd8. Previously misannotated as a putative sulfatase/phosphatase, elaD is an efficient and specific deubiquitinating enzyme in vitro. Interestingly, elaD is present in all intestinal pathogenic E. coli strains, but conspicuously absent from extraintestinal pathogenic strains (ExPECs). Further homologs of this protease can be found in Acanthamoeba Polyphaga Mimivirus, and in Alpha-, Beta-and Gammaproteobacteria. CONCLUSION: The expression of ULP/SENP-related hydrolases in bacteria therefore extends to plant pathogens and medically relevant strains of Escherichia coli, Legionella pneumophila, Rickettsiae, Chlamydiae, and Salmonellae, in which the elaD ortholog sseL has recently been identified as a virulence factor with deubiquitinating activity. As a counterpoint, our phylogenetic and functional examination reveals that ancient eukaryotic ULP/SENP proteases also have the potential of ubiquitin-specific hydrolysis, suggesting an early common origin of this peptidase clan.

negative: Mucosal immunity and the eradication of polio.

negative: The effects of a novel adjuvant complex/Eimeria profilin vaccine on the intestinal host immune response against live E. acervulina challenge infection Abstract The effects of a novel adjuvant composed of Quil A, cholesterol, dimethyl dioctadecyl ammonium bromide, and Carbopol (QCDC) on protective immunity against avian coccidiosis following immunization with an Eimeria recombinant protein were determined. Broiler chickens were subcutaneously immunized with isotonic saline (control), Eimeria recombinant profilin alone, or profilin emulsified with QCDC at 1 and 7 days post-hatch, and orally challenged with live Eimeria acervulina at 7 days following the last immunization. Body weight gains, gut lesion scores, fecal oocyst outputs, profilin serum antibody titers, lymphocyte proliferation, and intestinal cytokine transcript levels were assessed as measures of protective immunity. Chickens immunized with profilin plus QCDC showed increased body weight gains and decreased intestinal lesion scores compared with the profilin only or control groups. However, no differences were found in fecal oocyst shedding among the three groups. Profilin serum antibody titers and antigen-induced peripheral blood lymphocyte proliferation in the profilin/QCDC group were higher compared with the profilin only and control groups. Finally, while immunization with profilin alone or profilin plus QCDC uniformly increased the levels of intestinal transcripts encoding all cytokines examined (IL-1β, IL-10, IL-12, IL-15, IL-17F, and IFN-γ) compared with the control group, transcripts for IL-10 and IL-17F were further increased in the profilin/QCDC group compared with the profilin only group. In summary, this study provides the first evidence of the immunoenhancing activities of QCDC adjuvant in poultry.

negative: Porcine Coronaviruses Transmissible gastroenteritis virus (TGEV), porcine epidemic diarrhoea virus (PEDV), and porcine deltacoronavirus (PDCoV) are enteropathogenic coronaviruses (CoVs) of swine. TGEV appearance in 1946 preceded identification of PEDV (1971) and PDCoV (2009) that are considered as emerging CoVs. A spike deletion mutant of TGEV associated with respiratory tract infection in piglets appeared in 1984 in pigs in Belgium and was designated porcine respiratory coronavirus (PRCV). PRCV is considered non-pathogenic because the infection is very mild or subclinical. Since PRCV emergence and rapid spread, most pigs have become immune to both PRCV and TGEV, which has significantly reduced the clinical and economic importance of TGEV. In contrast, PDCoV and PEDV are currently expanding their geographic distribution, and there are reports on the circulation of TGEV-PEDV recombinants that cause a disease clinically indistinguishable from that associated with the parent viruses. TGEV, PEDV and PDCoV cause acute gastroenteritis in pigs (most severe in neonatal piglets) and matches in their clinical signs and pathogenesis. Necrosis of the infected intestinal epithelial cells causes villous atrophy and malabsorptive diarrhoea. Profuse diarrhoea frequently combined with vomiting results in dehydration, which can lead to the death of piglets. Strong immune responses following natural infection protect against subsequent homologous challenge; however, these viruses display no cross-protection. Adoption of advance biosecurity measures and effective vaccines control and prevent the occurrence of diseases due to these porcine-associated CoVs. Recombination and reversion to virulence are the risks associated with generally highly effective attenuated vaccines necessitating further research on alternative vaccines to ensure their safe application in the field.

negative: Host cell autophagy promotes BK virus infection Abstract Autophagy is important for a variety for virus life cycles. We sought to determine the role of autophagy in human BK polyomavirus (BKPyV) infection. The addition excess amino acids during viral infection reduced BKPyV infection. Perturbing autophagy levels using inhibitors, 3-MA, bafilomycin A1, and spautin-1, also reduced infection, while rapamycin treatment of host cells increased infection. siRNA knockdown of autophagy genes, ATG7 and Beclin-1, corresponded to a decrease in BKPyV infection. BKPyV infection not only correlated with autophagosome formation, but also virus particles localized to autophagy-specific compartments early in infection. These data support a novel role for autophagy in the promotion of BKPyV infection.

negative: Age distribution of cases caused by different influenza viruses

negative: Novel coronavirus: From discovery to clinical diagnostics Abstract A novel coronavirus designated as 2019-nCoV first appeared in Wuhan, China in late December 2019. Dozens of people died in China, and thousands of people infected as 2019-nCoV continues to spread around the world. We have described the discovery, emergence, genomic characteristics, and clinical diagnostics of 2019-nCoV.

negative: Structural Insights into Immune Recognition of the Severe Acute Respiratory Syndrome Coronavirus S Protein Receptor Binding Domain Abstract The spike (S) protein of the severe acute respiratory syndrome coronavirus (SARS-CoV) is responsible for host cell attachment and fusion of the viral and host cell membranes. Within S the receptor binding domain (RBD) mediates the interaction with angiotensin-converting enzyme 2 (ACE2), the SARS-CoV host cell receptor. Both S and the RBD are highly immunogenic and both have been found to elicit neutralizing antibodies. Reported here is the X-ray crystal structure of the RBD in complex with the Fab of a neutralizing mouse monoclonal antibody, F26G19, elicited by immunization with chemically inactivated SARS-CoV. The RBD–F26G19 Fab complex represents the first example of the structural characterization of an antibody elicited by an immune response to SARS-CoV or any fragment of it. The structure reveals that the RBD surface recognized by F26G19 overlaps significantly with the surface recognized by ACE2 and, as such, suggests that F26G19 likely neutralizes SARS-CoV by blocking the virus–host cell interaction.

negative: Evaluation of protection conferred by a vaccination program based on the H120 and CR88 commercial vaccines against a field variant of avian infectious bronchitis virus Abstract Due to serotype variations among different avian infectious bronchitis viruses isolated in Tunisia since 2000, protection of chicks, especially broiler flocks, with Mass H120 vaccine often fails. Therefore, association of CR88 (793B type) with H120 vaccines was used for better response. Challenge experiments were then conducted to evaluate tracheal and renal cross-protection in chickens immunized via nasal and eye drops. Conferred protection was measured by clinical signs and macroscopic lesions observed, based on scores attributed according to their severities. The results showed a low protection conferred by H120 alone, as vaccination did not reduce tracheal and kidney lesions (70% scored as 3) after TN20/00 virus challenge, which also led to 10% mortality. Conversely, the challenge results indicated that the combination of the 2 strains (H120/CR88) allow high protection. Based on the results of the challenge experiments, a vaccination protocol coupling CR88 to H120 was applied for industrial broiler flocks. Clinical observations and serological results confirmed that association of heterologous serotypes (H120 and CR88 vaccines) increased the levels of protection against infectious bronchitis viruses compared with the H120 vaccine given alone.

negative: In Vitro Antiviral Activity and Projection of Optimized Dosing Design of Hydroxychloroquine for the Treatment of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) BACKGROUND: The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) first broke out in Wuhan (China) and subsequently spread worldwide. Chloroquine has been sporadically used in treating SARS-CoV-2 infection. Hydroxychloroquine shares the same mechanism of action as chloroquine, but its more tolerable safety profile makes it the preferred drug to treat malaria and autoimmune conditions. We propose that the immunomodulatory effect of hydroxychloroquine also may be useful in controlling the cytokine storm that occurs late-phase in critically ill SARS-CoV-2 infected patients. Currently, there is no evidence to support the use of hydroxychloroquine in SARS-CoV-2 infection. METHODS: The pharmacological activity of chloroquine and hydroxychloroquine was tested using SARS-CoV-2 infected Vero cells. Physiologically-based pharmacokinetic models (PBPK) were implemented for both drugs separately by integrating their in vitro data. Using the PBPK models, hydroxychloroquine concentrations in lung fluid were simulated under 5 different dosing regimens to explore the most effective regimen whilst considering the drug’s safety profile. RESULTS: Hydroxychloroquine (EC(50)=0.72 μM) was found to be more potent than chloroquine (EC(50)=5.47 μM) in vitro. Based on PBPK models results, a loading dose of 400 mg twice daily of hydroxychloroquine sulfate given orally, followed by a maintenance dose of 200 mg given twice daily for 4 days is recommended for SARS-CoV-2 infection, as it reached three times the potency of chloroquine phosphate when given 500 mg twice daily 5 days in advance. CONCLUSIONS: Hydroxychloroquine was found to be more potent than chloroquine to inhibit SARS-CoV-2 in vitro.

negative: Host-pathogen interactions during coronavirus infection of primary alveolar epithelial cells Viruses that infect the lung are a significant cause of morbidity and mortality in animals and humans worldwide. Coronaviruses are being associated increasingly with severe diseases in the lower respiratory tract. Alveolar epithelial cells are an important target for coronavirus infection in the lung, and infected cells can initiate innate immune responses to viral infection. In this overview, we describe in vitro models of highly differentiated alveolar epithelial cells that are currently being used to study the innate immune response to coronavirus infection. We have shown that rat coronavirus infection of rat alveolar type I epithelial cells in vitro induces expression of CXC chemokines, which may recruit and activate neutrophils. Although neutrophils are recruited early in infection in several coronavirus models including rat coronavirus. However, their role in viral clearance and/or immune-mediated tissue damage is not understood. Primary cultures of differentiated alveolar epithelial cells will be useful for identifying the interactions between coronaviruses and alveolar epithelial cells that influence the innate immune responses to infection in the lung. Understanding the molecular details of these interactions will be critical for the design of effective strategies to prevent and treat coronavirus infections in the lung.

negative: Clinical exacerbation of SARS‐CoV2 infection after fingolimod withdrawal The role of disease‐modifying therapies in patients with autoimmune disorders during SARS‐CoV2 infection is controversial. Immunocompromised patients could have a more severe COVID‐19 disease, due to the absence of an adequate immune response against the SARS‐CoV‐2. However, therapies that act on immune response could play a protective role by dampening the cytokine release syndrome. Fingolimod is a drug used for immune therapy in patients with Multiple Sclerosis (MS) through the sequestration of activated lymphocytes in the lymph nodes. We report the case of a 57‐year‐old man with relapsing‐remitting MS treated with fingolimod that showed a reactivation of COVID‐19 with signs of hyperinflammation syndrome after fingolimod withdrawal. Our case suggests that discontinuation of fingolimod during COVID‐19 could imply a worsening of SARS‐CoV2 infection. This article is protected by copyright. All rights reserved.

negative: COVID-19 – Considerations for the paediatric rheumatologist Abstract The novel coronavirus SARS-CoV2 is a threat to the health and well-being of millions of lifes across the globe. A significant proportion of adult patients require hospitalisation and may develop severe life-threatening complications. Children, on the other hand, can carry and transmit the virus, but usually do not develop severe disease. Mortality in the paediatric age-group is relatively low. Differences in virus containment and clearance, as well as reduced inflammation-related tissue and organ damage may be caused by age-specific environmental and host factors. Since severe complications in adults are frequently caused by uncontrolled immune responses and a resulting “cytokine storm” that may be controlled by targeted blockade of cytokines, previously established treatment with immunosuppressive treatments may indeed protect children from complications.

negative: Global research trends of World Health Organization’s top eight emerging pathogens BACKGROUND: On December 8(th), 2015, World Health Organization published a priority list of eight pathogens expected to cause severe outbreaks in the near future. To better understand global research trends and characteristics of publications on these emerging pathogens, we carried out this bibliometric study hoping to contribute to global awareness and preparedness toward this topic. METHOD: Scopus database was searched for the following pathogens/infectious diseases: Ebola, Marburg, Lassa, Rift valley, Crimean-Congo, Nipah, Middle Eastern Respiratory Syndrome (MERS), and Severe Respiratory Acute Syndrome (SARS). Retrieved articles were analyzed to obtain standard bibliometric indicators. RESULTS: A total of 8619 journal articles were retrieved. Authors from 154 different countries contributed to publishing these articles. Two peaks of publications, an early one for SARS and a late one for Ebola, were observed. Retrieved articles received a total of 221,606 citations with a mean ± standard deviation of 25.7 ± 65.4 citations per article and an h-index of 173. International collaboration was as high as 86.9%. The Centers for Disease Control and Prevention had the highest share (344; 5.0%) followed by the University of Hong Kong with 305 (4.5%). The top leading journal was Journal of Virology with 572 (6.6%) articles while Feldmann, Heinz R. was the most productive researcher with 197 (2.3%) articles. China ranked first on SARS, Turkey ranked first on Crimean-Congo fever, while the United States of America ranked first on the remaining six diseases. Of retrieved articles, 472 (5.5%) were on vaccine – related research with Ebola vaccine being most studied. CONCLUSION: Number of publications on studied pathogens showed sudden dramatic rise in the past two decades representing severe global outbreaks. Contribution of a large number of different countries and the relatively high h-index are indicative of how international collaboration can create common health agenda among distant different countries.

negative: Las enseñanzas del síndrome respiratorio agudo grave

negative: Echoes of 2009 H1N1 Influenza Pandemic in the COVID Pandemic Abstract The severe acute respiratory syndrome–related coronavirus-2 (SARS-CoV2) pandemic that has engulfed the globe has had incredible effects on health care systems and economic activity. Social distancing and school closures have played a central role in public health efforts to counter the coronavirus disease 2019 (COVID)-19 pandemic. The most recent global pandemic prior to COVID-19 was the 2009 pandemic, hemagglutinin type 1 and neuraminidase type 1 (H1N1) influenza. The course of events in 2009 offer some rich lessons that could be applied to the current COVID-19 pandemic. This commentary highlights some of the most relevant points and a discussion of possible outcomes of the COVID-19 pandemic. © 2020 Elsevier Inc.

negative: Molecular conservation and differential mutation on ORF3a gene in Indian SARS-CoV2 genomes Abstract A global emergency due to the COVID-19 pandemic demands various studies related to genes and genomes of the SARS-CoV2. Among other important proteins, the role of accessory proteins are of immense importance in replication, regulation of infections of the coronavirus in the hosts. The largest accessory protein in the SARS-CoV2 genome is ORF3a which modulates the host response to the virus infection and consequently it plays an important role in pathogenesis. In this study, an attempt is made to decipher the conservation of nucleotides, dimers, codons and amino acids in the ORF3a genes across thirty-two genomes of Indian patients. ORF3a gene possesses single and double point mutations in Indian SARS-CoV2 genomes suggesting the change of SARS-CoV2's virulence property in Indian patients. We find that the parental origin of the ORF3a gene over the genomes of SARS-CoV2 and Pangolin-CoV is same from the phylogenetic analysis based on conservation of nucleotides and so on. This study highlights the accumulation of mutation on ORF3a in Indian SARS-CoV2 genomes which may provide the designing therapeutic approach against SARS-CoV2.

negative: COVID-19: A promising cure for the global panic Abstract The novel Coronavirus disease 2019 (COVID-19) is caused by SARS-CoV-2, which is the causative agent of a potentially fatal disease that is of great global public health concern. The outbreak of COVID-19 is wreaking havoc worldwide due to inadequate risk assessment regarding the urgency of the situation. The COVID-19 pandemic has entered a dangerous new phase. When compared with SARS and MERS, COVID-19 has spread more rapidly, due to increased globalization and adaptation of the virus in every environment. Slowing the spread of the COVID-19 cases will significantly reduce the strain on the healthcare system of the country by limiting the number of people who are severely sick by COVID-19 and need hospital care. Hence, the recent outburst of COVID-19 highlights an urgent need for therapeutics targeting SARS-CoV-2. Here, we have discussed the structure of virus; varying symptoms among COVID-19, SARS, MERS and common flu; the probable mechanism behind the infection and its immune response. Further, the current treatment options, drugs available, ongoing trials and recent diagnostics for COVID-19 have been discussed. We suggest traditional Indian medicinal plants as possible novel therapeutic approaches, exclusively targeting SARS-CoV-2 and its pathways.

negative: The effect of uncontrolled travelers and social distancing on the spread of novel coronavirus disease (COVID-19) in Colombia

negative: Cross-subtype Immunity against Avian Influenza in Persons Recently Vaccinated for Influenza Avian influenza virus (H5N1) can be transmitted to humans, resulting in a severe or fatal disease. The aim of this study was to evaluate the immune cross-reactivity between human and avian influenza (H5N1) strains in healthy donors vaccinated for seasonal influenza A (H1N1)/(H3N2). A small frequency of CD4 T cells specific for subtype H5N1 was detected in several persons at baseline, and seasonal vaccine administration enhanced the frequency of such reactive CD4 T cells. We also observed that seasonal vaccination is able to raise neutralizing immunity against influenza (H5N1) in a large number of donors. No correlation between influenza-specific CD4 T cells and humoral responses was observed. N1 may possibly be a target for both cellular and humoral cross-type immunity, but additional experiments are needed to clarify this point. These findings highlight the possibility of boosting cross-type cellular and humoral immunity against highly pathogenic avian influenza A virus subtype H5N1 by seasonal influenza vaccination.

negative: Chapter 8 The Middle East Respiratory Syndrome Coronavirus: An Emerging Virus of Global Threat Abstract Middle East respiratory syndrome (MERS) is a viral respiratory illness caused by a coronavirus (CoV), first identified in Saudi Arabia in 2012. Since then, almost 2000 cases have been reported from 27 countries, with Saudi Arabia being the epicenter. This newly emerging virus is highly pathogenic and has a case mortality rate of 35%. It is similar to the CoV causing severe acute respiratory syndrome CoV (SARS-CoV) in that both belong to the genus beta CoVs that are of zoonotic origin and cause lower respiratory infection. The natural reservoir for MERS-CoV remains unknown. Serological studies indicate that most dromedary camels in the Middle East have been infected with this virus, and they maybe the potential intermediate host. However, the mode of transmission from camels to humans is poorly understood. The majority of confirmed human cases have resulted from human-to-human transmission, most probably via respiratory route. Patients most at risk of developing severe MERS-CoV infection appear to be those with underlying conditions such as diabetes, hypertension, obesity, cardiac diseases, chronic respiratory diseases, and cancer. Unlike SARS-CoV, MERS-CoV is considered an ongoing public health problem, particularly for the Middle East region. In this chapter, we outline the prevailing information regarding the emergence and epidemiology of this virus, its mode of transmission and pathogenicity, its clinical features, and the potential strategies for prevention.

negative: Microbiology The management and containment of many treatable and preventable infectious diseases in resource-poor countries is limited by the failure to make an accurate diagnosis. Most of the world's population lacks access to accurate, affordable, easy-to-use, quality-assured, reliable, and accessible diagnostic tests and misdiagnosis of infectious diseases is common and compromises patient care. Laboratory diagnostics are also needed for the detection and surveillance of the increasing levels of antimicrobial resistance. Accurate clinical diagnosis in resource-poor settings relies strongly on the laboratory service, and the need to support the development of a quality-assured laboratory service in such settings is increasingly recognized. International organizations are actively working with local and national providers to improve laboratory services. The development of laboratory services will contribute to improved health for the local population, protection against emerging pathogens, and ensure better use of scarce health care resources.

negative: A phase trial of the oral Lactobacillus casei vaccine polarizes Th2 cell immunity against transmissible gastroenteritis coronavirus infection Transmissible gastroenteritis coronavirus (TGEV) is a member of the genus Coronavirus, family Coronaviridae, order Nidovirales. TGEV is an enteropathogenic coronavirus that causes highly fatal acute diarrhoea in newborn pigs. An oral Lactobacillus casei (L. casei) vaccine against anti-transmissible gastroenteritis virus developed in our laboratory was used to study mucosal immune responses. In this L. casei vaccine, repetitive peptides expressed by L. casei (specifically the MDP and tuftsin fusion protein (MT)) were repeated 20 times and the D antigenic site of the TGEV spike (S) protein was repeated 6 times. Immunization with recombinant Lactobacillus is crucial for investigations of the effect of immunization, such as the first immunization time and dose. The first immunization is more important than the last immunization in the series. The recombinant Lactobacillus elicited specific systemic and mucosal immune responses. Recombinant L. casei had a strong potentiating effect on the cellular immunity induced by the oral L. casei vaccine. However, during TGEV infection, the systemic and local immune responses switched from Th1 to Th2-based immune responses. The systemic humoral immune response was stronger than the cellular immune response after TGEV infection. We found that the recombinant Lactobacillus stimulated IL-17 expression in both the systemic and mucosal immune responses against TGEV infection. Furthermore, the Lactobacillus vaccine stimulated an anti-TGEV infection Th17 pathway. The histopathological examination showed tremendous potential for recombinant Lactobacillus to enable rapid and effective treatment for TGEV with an intestinal tropism in piglets. The TGEV immune protection was primarily dependent on mucosal immunity.

negative: Advancements in prophylactic and therapeutic nanovaccines Abstract Vaccines activate suitable immune responses to fight against diseases but can possess limitations such as compromised efficacy and immunogenic responses, poor stability, and requirement of adherence to multiple doses. ‘Nanovaccines’ have been explored to elicit a strong immune response with the advantages of nano-sized range, high antigen loading, enhanced immunogenicity, controlled antigen presentation, more retention in lymph nodes and promote patient compliance by a lower frequency of dosing. Various types of nanoparticles with diverse pathogenic or foreign antigens can help to overcome immunotolerance and alleviate the need of booster doses as required with conventional vaccines. Nanovaccines have the potential to induce both cell-mediated and antibody-mediated immunity and can render long-lasting immunogenic memory. With such properties, nanovaccines have shown high potential for the prevention of infectious diseases such as acquired immunodeficiency syndrome (AIDS), malaria, tuberculosis, influenza, and cancer. Their therapeutic potential has also been explored in the treatment of cancer. The various kinds of nanomaterials used for vaccine development and their effects on immune system activation have been discussed with special relevance to their implications in various pathological conditions. Statement of Significance Interaction of nanoparticles with the immune system has opened multiple avenues to combat a variety of infectious and non-infectious pathological conditions. Limitations of conventional vaccines have paved the path for nanomedicine associated benefits with a hope of producing effective nanovaccines. This review highlights the role of different types of nanovaccines and the role of nanoparticles in modulating the immune response of vaccines. The applications of nanovaccines in infectious and non-infectious diseases like malaria, tuberculosis, AIDS, influenza, and cancers have been discussed. It will help the readers develop an understanding of mechanisms of immune activation by nanovaccines and design appropriate strategies for novel nanovaccines.

negative: Optimizing the molecular diagnosis of Covid-19 by combining RT-PCR and a pseudo-convolutional machine learning approach to characterize virus DNA sequences The proliferation of the SARS-Cov-2 virus to the whole world caused more than 250,000 deaths worldwide and over 4 million confirmed cases. The severity of Covid-19, the exponential rate at which the virus proliferates, and the rapid exhaustion of the public health resources are critical factors. The RT-PCR with virus DNA identification is still the benchmark Covid-19 diagnosis method. In this work we propose a new technique for representing DNA sequences: they are divided into smaller sequences with overlap in a pseudo-convolutional approach, and represented by co-occurrence matrices. This technique analyzes the DNA sequences obtained by the RT-PCR method, eliminating sequence alignment. Through the proposed method, it is possible to identify virus sequences from a large database: 347,363 virus DNA sequences from 24 virus families and SARS-Cov-2. Experiments with all 24 virus families and SARS-Cov-2 (multi-class scenario) resulted 0.822222 ± 0.05613 for sensitivity and 0.99974 ± 0.00001 for specificity using Random Forests with 100 trees and 30% overlap. When we compared SARS-Cov-2 with similar-symptoms virus families, we got 0.97059 ± 0.03387 for sensitivity, and 0.99187 ± 0.00046 for specificity with MLP classifier and 30% overlap. In the real test scenario, in which SARS-Cov-2 is compared to Coronaviridae and healthy human DNA sequences, we got 0.98824 ± 001198 for sensitivity and 0.99860 ± 0.00020 for specificity with MLP and 50% overlap. Therefore, the molecular diagnosis of Covid-19 can be optimized by combining RT-PCR and our pseudo-convolutional method to identify SARS-Cov-2 DNA sequences faster with higher specificity and sensitivity.

negative: Current status of treatment for 2019 novel coronavirus pneumonia/ 中华微生物学和免疫学杂志 2019 novel coronavirus (2019-nCoV) is a new member of coronavirus family that can cause serious respiratory diseases after the emergence of severe acute respiratory syndrome-coronavirus (SARS-CoV) and middle east respiratory syndrome-coronavirus (MERS-CoV). At present, there is no specific antiviral drug targeting 2019-nCoV. In facing of the increasingly serious epidemic of 2019 novel coronavirus pneumonia and the urgent needs in drug treatment strategies, this paper reviewed the current research situation and progress in antiviral treatment for the newly identified disease.

negative: Current advancements and potential strategies in the development of MERS-CoV vaccines Middle East respiratory syndrome (MERS) is a newly emerging infectious disease caused by a novel coronavirus, MERS-coronavirus (MERS-CoV), a new member in the lineage C of β-coronavirus (β-CoV). The increased human cases and high mortality rate of MERS-CoV infection make it essential to develop safe and effective vaccines. In this review, the current advancements and potential strategies in the development of MERS vaccines, particularly subunit vaccines based on MERS-CoV spike (S) protein and its receptor-binding domain (RBD), are discussed. How to improve the efficacy of subunit vaccines through novel adjuvant formulations and routes of administration as well as currently available animal models for evaluating the in vivo efficacy of MERS-CoV vaccines are also addressed. Overall, these strategies may have important implications for the development of effective and safe vaccines for MERS-CoV in the future.

negative: Robust and optimal predictive control of the COVID-19 outbreak We investigate adaptive strategies to robustly and optimally control the COVID-19 pandemic via social distancing measures based on the example of Germany. Our goal is to minimize the number of fatalities over the course of two years without inducing excessive social costs. We consider a tailored model of the German COVID-19 outbreak with different parameter sets to design and validate our approach. Our analysis reveals that an open-loop optimal control policy can significantly decrease the number of fatalities when compared to simpler policies under the assumption of exact model knowledge. In a more realistic scenario with uncertain data and model mismatch, a feedback strategy that updates the policy weekly using model predictive control (MPC) leads to a reliable performance, even when applied to a validation model with deviant parameters. On top of that, we propose a robust MPC-based feedback policy using interval arithmetic that adapts the social distancing measures cautiously and safely, thus leading to a minimum number of fatalities even if measurements are inaccurate and the infection rates cannot be precisely specified by social distancing. Our theoretical findings support various recent studies by showing that 1) adaptive feedback strategies are required to reliably contain the COVID-19 outbreak, 2) well-designed policies can significantly reduce the number of fatalities compared to simpler ones while keeping the amount of social distancing measures on the same level, and 3) imposing stronger social distancing measures early on is more effective and cheaper in the long run than opening up too soon and restoring stricter measures at a later time.

negative: Thromboinflammation and the hypercoagulability of COVID-19. The pathogenic coronavirus has been wreaking havoc worldwide since January. Infection with SARS-CoV-2 is problematic as no one has prior immunity, and no specific antiviral treatments are available. While many people with COVID-19 develop mild to moderate symptoms, some develop profound seemingly unchecked inflammatory responses leading to acute lung injury and hypoxemic respiratory failure, the most common cause for death.

negative: An anterior mediastinal mass: delayed airway compression and using a double lumen tube for airway patency. Perioperative management of patients with an anterior mediastinal mass is difficult. We present a 35-year-old woman who showed delayed compression of the carina and left main bronchus despite no preoperative respiratory signs, symptoms, or radiologic findings due to an anterior mediastinal mass and uneventful stepwise induction of general anesthesia. Even use of a fiberoptic bronchoscope (FB) after induction of anesthesia was not helpful to predict delayed compression of the airway. Therefore, the anesthesiologist and the cardiothoracic surgeon must prepare for unexpected delayed compression of the airway, even in low risk patients who are asymptomatic or mildly symptomatic without postural symptoms or radiographic evidence of significant compression of structures. We also describe successful management for the compressed carina and left main bronchus with a double lumen tube (DLT) as a stent during surgery. FB guided DLT intubation is a possible solution to maintain airway patency.

negative: Coronavirus infections: Epidemiological, clinical and immunological features and hypotheses Coronaviruses (CoVs) are a large family of enveloped, positive-strand RNA viruses Four human CoVs (HCoVs), the non-severe acute respiratory syndrome (SARS)-like HCoVs (namely HCoV 229E, NL63, OC43, and HKU1), are globally endemic and account for a substantial fraction of upper respiratory tract infections Non-SARS-like CoV can occasionally produce severe diseases in frail subjects but do not cause any major (fatal) epidemics In contrast, SARS like CoVs (namely SARS-CoV and Middle-East respiratory syndrome coronavirus, MERS-CoV) can cause intense short-lived fatal outbreaks The current epidemic caused by the highly contagious SARS-CoV-2 and its rapid spread globally is of major concern There is scanty knowledge on the actual pandemic potential of this new SARS-like virus It might be speculated that SARS-CoV-2 epidemic is grossly underdiagnosed and that the infection is silently spreading across the globe with two consequences: (i) clusters of severe infections among frail subjects could haphazardly occur linked to unrecognized index cases;(ii) the current epidemic could naturally fall into a low-level endemic phase when a significant number of subjects will have developed immunity Understanding the role of paucisymptomatic subjects and stratifying patients according to the risk of developing severe clinical presentations is pivotal for implementing reasonable measures to contain the infection and to reduce its mortality Whilst the future evolution of this epidemic remains unpredictable, classic public health strategies must follow rational patterns The emergence of yet another global epidemic underscores the permanent challenges that infectious diseases pose and underscores the need for global cooperation and preparedness, even during inter-epidemic periods

negative: The Global Impact of the Coronavirus Pandemic The coronavirus pandemic has engulfed the nations of the world for the first five months of 2020 and altered the pace, fabric and nature of our lives. In this overview accompanying the Special Issue of Cytokine & Growth Factor Reviews, we examine some of the many social and scientific issues impacted by SARS-CoV2 – personal lives, economy, scientific communication, the environment. International members of Istituto Pasteur in Rome and INITIATE, the Marie Curie Training Network reflect on the lasting global impact of the coronavirus pandemic.

negative: The deadly coronaviruses: The 2003 SARS pandemic and the 2020 novel coronavirus epidemic in China Abstract The 2019-nCoV is officially called SARS-CoV-2 and the disease is named COVID-19. This viral epidemic in China has led to the deaths of over 1800 people, mostly elderly or those with an underlying chronic disease or immunosuppressed state. This is the third serious Coronavirus outbreak in less than 20 years, following SARS in 2002–2003 and MERS in 2012. While human strains of Coronavirus are associated with about 15% of cases of the common cold, the SARS-CoV-2 may present with varying degrees of severity, from flu-like symptoms to death. It is currently believed that this deadly Coronavirus strain originated from wild animals at the Huanan market in Wuhan, a city in Hubei province. Bats, snakes and pangolins have been cited as potential carriers based on the sequence homology of CoV isolated from these animals and the viral nucleic acids of the virus isolated from SARS-CoV-2 infected patients. Extreme quarantine measures, including sealing off large cities, closing borders and confining people to their homes, were instituted in January 2020 to prevent spread of the virus, but by that time much of the damage had been done, as human-human transmission became evident. While these quarantine measures are necessary and have prevented a historical disaster along the lines of the Spanish flu, earlier recognition and earlier implementation of quarantine measures may have been even more effective. Lessons learned from SARS resulted in faster determination of the nucleic acid sequence and a more robust quarantine strategy. However, it is clear that finding an effective antiviral and developing a vaccine are still significant challenges. The costs of the epidemic are not limited to medical aspects, as the virus has led to significant sociological, psychological and economic effects globally. Unfortunately, emergence of SARS-CoV-2 has led to numerous reports of Asians being subjected to racist behavior and hate crimes across the world.

negative: Numerical study of SARS epidemic model with the inclusion of diffusion in the system Abstract This paper deals with the numerical study of population model based on the epidemics of Severe Acute Respiratory Syndrome (SARS). SEIJR (susceptible, exposed, infected, diagnosed, recovered) model of SARS epidemic is considered with net in flow of individuals into a region. Transmission of disease is analyzed by solving the system of differential equations using numerical methods with different initial population distributions. The effect of diffusion on the spread of disease is examined. Stability is established for the numerical solutions. Effects of interventions (medical and non medical) are also analyzed.

negative: Vaccine design for severe acute respiratory syndrome coronavirus. Severe acute respiratory syndrome (SARS) is an emerging infectious disease caused by a new coronavirus (SARS-CoV). Recent studies suggest that SARS-CoV is zoonotic and may have a broad host range besides humans. Although the global outbreak of SARS has been contained, there are serious concerns over its re-emergence and bioterrorism potential. As a part of preparedness, development of a safe and effective vaccine is one of the highest priorities in fighting SARS. A number of candidate vaccines, using a variety of approaches, are under development. The first vaccine tested in clinical trial is made from the inactivated form of SARS-CoV. Several live attenuated, genetically engineered or vector vaccines encoding the SARS-CoV spike (S) protein have been in pre-clinical studies. These vaccine candidates are effective in terms of eliciting protective immunity in the vaccinated animals. However, caution should be taken with the safety of whole virus or full-length S protein-based immunogens in humans because they may induce harmful immune or inflammatory responses. We propose to use the receptor-binding domain (RBD) of SARS-CoV S protein (residues 318--510) for developing a safe and effective subunit SARS vaccine, as it is not only a functional domain that mediates virus-receptor binding but also a major neutralization determinant of SARSCoV. It has been demonstrated that the RBD of SARS-CoV S protein contains multiple conformational epitopes capable of inducing highly potent neutralizing antibody responses and protective immunity.

negative: Regulation of the p38 mitogen-activated protein kinase and dual-specificity phosphatase 1 feedback loop modulates the induction of interleukin 6 and 8 in cells infected with coronavirus infectious bronchitis virus Abstract Induction of pro-inflammatory response is a crucial cellular process that detects and controls the invading viruses at early stages of the infection. Along with other innate immunity, this nonspecific response would either clear the invading viruses or allow the adaptive immune system to establish an effective antiviral response at late stages of the infection. The objective of this study was to characterize cellular mechanisms exploited by coronavirus infectious bronchitis virus (IBV) to regulate the induction of two pro-inflammatory cytokines, interleukin (IL)-6 and IL-8, at the transcriptional level. The results showed that IBV infection of cultured human and animal cells activated the p38 mitogen-activated protein kinase (MAPK) pathway and induced the expression of IL-6 and IL-8. Meanwhile, IBV has developed a strategy to counteract the induction of IL-6 and IL-8 by inducing the expression of dual-specificity phosphatase 1 (DUSP1), a negative regulator of the p38 MAPK, in order to limit the production of an excessive amount of IL-6 and IL-8 in the infected cells. As activation of the p38 MAPK pathway and induction of IL-6 and IL-8 may have multiple pathogenic effects on the whole host as well as on individual infected cells, regulation of the p38 MAPK and DUSP1 feedback loop by IBV may modulate the pathogenesis of the virus.

negative: Return of the Coronavirus: 2019-nCoV The emergence of a novel coronavirus (2019-nCoV) has awakened the echoes of SARS-CoV from nearly two decades ago. Yet, with technological advances and important lessons gained from previous outbreaks, perhaps the world is better equipped to deal with the most recent emergent group 2B coronavirus.

negative: Inborn errors of immunity and coronovirus pandemic/ İmmün sistemin doğuştan kusurları ve korona virüs pandemisi Inborn errors of immunity (IEI) are a heterogeneous group of diseases, typically characterized by recurrent ve severe infections, autoimmunity, autoinflammatory, allergic diseases and cancer. Since their immune response to pathogens are impaired, they have high risk for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, which has spread more than 180 countries. It is reported that two groups of people were prone to life-threatening coronavirus disease 2019 (COVID-19): aged (>65 years of age) and people with comorbidities such as hypertension, cardiovascular diseases, chronic lung, renal and liver diseases, diabetes mellitus, obesity, including immunodeficiencies. The aim of this paper is to present information about the new coronavirus, modes of transmission, clinical findings, diagnostic procedures, treatment modalities of COVID-19 to the physicians who is caring patients with primary immunodeficiency. Patients with primary immunodeficiencies, must exclusively rely on hygiene and protective measures to combat SARS-CoV-2, since vaccines or effective antiviral treatments against COVID-19 are still not available.

negative: Social and administrative issues related to the COVID-19 pandemic in Pakistan: better late than never The study critically reviewed Pakistan’s provincial updates of coronavirus disease 2019 (COVID-19) and discussed the current challenges faced by the government in a given context. The coronavirus-associated death tolls have been increasing rapidly in a country. The provincial status of confirmed cases of coronavirus is higher in Punjab, followed by the Sindh, Khyber Pakhtunkhwa (KPK), and Balochistan. The case fatality ratio shows that KPK has a higher ratio, i.e., 5.11%, followed by the Punjab, i.e., 1.82%; Sindh, i.e., 1.80%; Balochistan, i.e., 1.28%; Gilgit-Baltistan, i.e., 0.71%; and Federal territory, i.e., 0.66%. The country has a less testing capacity to identify more suspected coronavirus patients. The study calculated that if we increase five times our testing capacity from the current date, the total registered cases will be reached to 137,370 and death tolls will increase up to 3090. It is highly needed to increase testing capacity across Pakistan in order to minimize the outbreak of coronavirus. The provincial government should follow the Federal Government instructions to contain coronavirus by increasing testing capacities, tracing suspected patients, smart lockdowns, emergency relief to the poor, and vigilant monitoring system.

negative: Tomar medidas preventivas inmediatamente: evidencia de China sobre el COVID-19

negative: Transmission Cycle of SARS-CoV and SARS-CoV-2 Severe acute respiratory syndrome (SARS) is a pandemic that has shocked the world twice over the last two decades caused by a highly transmissible and pathogenic coronavirus (CoV). It causes disease in the lower respiratory tract in humans that was first reported in late 2002 in Guangdong province, China, and later on in December 2019 in Wuhan, China. The two viruses designated as SARS-CoV and SARS-CoV-2, respectively, originated probably from the bat and infected humans via carrier animals. The constant recombination and evolution in the CoV genome may have facilitated their cross-species transmission resulting in recurrent emergence as a pandemic. This chapter intends to accumulate recent findings related to CoV transmission and tentative molecular mechanisms governing the process.

negative: Coalition: Advocacy for prospective clinical trials to test the post-exposure potential of hydroxychloroquine against COVID-19 Abstract Our coalition of public health experts, doctors, and scientists worldwide want to draw attention to the need for high-quality evaluation protocols of the potential beneficial effect of hydroxychloroquine (HCQ) as a post-exposure drug for exposed people, meaning people with close contact with positive tested patients, including home and medical caregivers. We have reviewed the mechanisms of antiviral effect of HCQ, the risk-benefit ratio taking into consideration the PK/PD of HCQ and the thresholds of efficacy. We have studied its use as an antimalarial, an antiviral, and an immunomodulating drug and concluded that the use of HCQ at does matching that of the standard treatment of Systemic Lupus erythematous, which has proven safety and efficacy in terms of HCQ blood and tissue concentration adapted to bodyweight (2,3), at 6 mg/kg/day 1 (loading dose) followed by 5 mg/kg/day, with a maximum limit of 600 mg/day in all cases should swiftly be clinically evaluated as a post-exposure drug for exposed people.

negative: Why are pregnant women susceptible to COVID-19? An immunological viewpoint Abstract The 2019 novel coronavirus disease (COVID-19) was first detected in December 2019 and became epidemic in Wuhan, Hubei Province, China. COVID-19 has been rapidly spreading out in China and all over the world. The virus causing COVID-19, SARS-CoV-2 has been known to be genetically similar to severe acute respiratory syndrome coronavirus (SARS-CoV) but distinct from it. Clinical manifestation of COVID-19 can be characterized by mild upper respiratory tract infection, lower respiratory tract infection involving non-life threatening pneumonia, and life-threatening pneumonia with acute respiratory distress syndrome. It affects all age groups, including newborns, to the elders. Particularly, pregnant women may be more susceptible to COVID-19 since pregnant women, in general, are vulnerable to respiratory infection. In pregnant women with COVID-19, there is no evidence for vertical transmission of the virus, but an increased prevalence of preterm deliveries has been noticed. The COVID-19 may alter immune responses at the maternal-fetal interface, and affect the well-being of mothers and infants. In this review, we focused on the reason why pregnant women are more susceptible to COVID-19 and the potential maternal and fetal complications from an immunological viewpoint.

negative: Comparative seasonalities of influenza A, B and ‘common cold’ coronaviruses – setting the scene for SARSCoV-2 infections and possible unexpected host immune interactions

negative: Cyclosporine therapy during the COVID-19 pandemic is not a reason for concern.

negative: Comparative analyses of SAR-CoV2 genomes from different geographical locations and other coronavirus family genomes reveals unique features potentially consequential to host-virus interaction and pathogenesis The ongoing pandemic of the coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV2). We have performed an integrated sequence-based analysis of SARS-CoV2 genomes from different geographical locations in order to identify its unique features absent in SARS-CoV and other related coronavirus family genomes, conferring unique infection, facilitation of transmission, virulence and immunogenic features to the virus. The phylogeny of the genomes yields some interesting results. Systematic gene level mutational analysis of the genomes has enabled us to identify several unique features of the SARS-CoV2 genome, which includes a unique mutation in the spike surface glycoprotein (A930V (24351C>T)) in the Indian SARS-CoV2, absent in other strains studied here. We have also predicted the impact of the mutations in the spike glycoprotein function and stability, using computational approach. To gain further insights into host responses to viral infection, we predict that antiviral host-miRNAs may be controlling the viral pathogenesis. Our analysis reveals nine host miRNAs which can potentially target SARS-CoV2 genes. Interestingly, the nine miRNAs do not have targets in SARS and MERS genomes. Also, hsa-miR-27b is the only unique miRNA which has a target gene in the Indian SARS-CoV2 genome. We also predicted immune epitopes in the genomes

negative: Impact of Middle East Respiratory Syndrome coronavirus (MERS‐CoV) on pregnancy and perinatal outcome BACKGROUND: Middle East Respiratory Syndrome coronavirus (MERS-CoV) is a viral respiratory disease. Most people infected with MERS-CoV develop severe acute respiratory illness. It was first reported in Saudi Arabia in 2012 and has since spread to several other countries. We report the clinical course of MERS-CoV infection in a pregnant woman who acquired the infection during the last trimester. CASE PRESENTATION: The patient is a 33-year-old female working as a critical care nurse. She was 32 weeks pregnant when she presented with respiratory symptoms after direct contact with a MERS-COV patient. Although the patient was in respiratory failure, necessitated mechanical ventilation, and intensive care (ICU) admission, a healthy infant was delivered. The mother recovered. To the best of our knowledge, this is the first reported case of a laboratory-confirmed Middle East Respiratory Syndrome Coronavirus in a pregnant woman. CONCLUSIONS: Middle East Respiratory Syndrome coronavirus (MERS-CoV) known to cause severe acute respiratory illness associated with a high risk of mortality Various factors may have contributed to the successful outcome of this patient such as young age, presentation during the last stages of pregnancy, and possible differences in immune response.

negative: The COVID-19 pandemic and the use of MS disease-modifying therapies

negative: A Critical HA1 Neutralizing Domain of H5N1 Influenza in an Optimal Conformation Induces Strong Cross-Protection The highly pathogenic avian influenza (HPAI) H5N1 viruses, especially the laboratory-generated H5N1 mutants, have demonstrated the potential to cross the species barrier and infect mammals and humans. Consequently, the design of an effective and safe anti-H5N1 vaccine is essential. We previously demonstrated that the full-length hemagglutinin 1 (HA1) could induce significant neutralizing antibody response and protection. Here, we intended to identify the critical neutralizing domain (CND) in an optimal conformation that can elicit strong cross-neutralizing antibodies and protection against divergent H5N1 strains. We thus constructed six recombinant proteins covering different regions of HA1 of A/Anhui/1/2005(H5N1), each of which was fused with foldon (Fd) and Fc of human IgG. We found that the critical fragment fused with Fd/Fc (HA-13–263-Fdc, H5 numbering) that could elicit the strongest neutralizing antibody response is located in the N-terminal region of HA1 (residues 13–263), which covers the receptor-binding domain (RBD, residues 112–263). We then constructed three additional recombinants fused with Fd plus His tag (HA-13–263-Fd-His), Fc only (HA-13–263-Fc), and His tag only (HA-13–263-His), respectively. We found that the HA-13–263-Fdc, which formed an oligomeric conformation, induced the strongest neutralizing antibody response and cross-protection against challenges of two tested H5N1 virus strains covering clade 1: A/VietNam/1194/2004 (VN/1194) or clade 2.3.4: A/Shenzhen/406H/06 (SZ/406H), while HA-13–263-Fc dimer and HA-13–263-Fd-His trimer elicited higher neutralizing antibody response and protection than HA-13–263-His monomer. These results suggest that the oligomeric form of the CND containing the RBD can be further developed as an effective and safe vaccine for cross-protection against divergent strains of H5N1 viruses.

negative: Recomendaciones sobre el manejo clínico de la infección por el «nuevo coronavirus» SARS-CoV2. Grupo de trabajo de la Asociación Española de Pediatría (AEP) Resumen El 31 de diciembre de 2019, la Comisión Municipal de Salud y Sanidad de Wuhan (provincia de Hubei, China) informó sobre la existencia de 27 casos de neumonía de etiología desconocida con inicio de síntomas el 8 de diciembre, incluyendo 7 casos graves, con exposición común a un mercado de marisco, pescado y animales vivos en la ciudad de Wuhan. El 7 de enero de 2020, las autoridades chinas identificaron como agente causante del brote un nuevo tipo de virus de la familia Coronaviridae, denominado temporalmente «nuevo coronavirus», 2019-nCoV. El 30 de enero de 2020 la Organización Mundial de la Salud (OMS) declara el brote una Emergencia Internacional. El día 11 de febrero la OMS le asigna el nombre de SARS-CoV2 e infección COVID-19 (Coronavirus Infectious Disease). El Ministerio de Sanidad convoca a las Sociedades de Especialidades para la elaboración de un protocolo clínico de manejo de la infección. La Asociación Española de Pediatría nombra un grupo de trabajo de las Sociedades de Infectología Pediátrica y Cuidados Intensivos Pediátricos que se encargan de elaborar las presentes recomendaciones con la evidencia disponible en el momento de su realización. Abstract On 31 December 2019, the Wuhan Municipal Committee of Health and Healthcare (Hubei Province, China) reported that there were 27 cases of pneumonia of unknown origin with symptoms starting on the 8 December. There were 7 serious cases with common exposure in market with shellfish, fish, and live animals, in the city of Wuhan. On 7 January 2020, the Chinese authorities identified that the agent causing the outbreak was a new type of virus of the Coronaviridae family, temporarily called «new coronavirus», 2019-nCoV. On January 30th, 2020, the World Health Organisation (WHO) declared the outbreak an International Emergency. On 11 February 2020 the WHO assigned it the name of SARS-CoV2 and COVID-19 (SARS-CoV2 and COVID-19). The Ministry of Health summoned the Specialties Societies to prepare a clinical protocol for the management of COVID-19. The Spanish Paediatric Association appointed a Working Group of the Societies of Paediatric Infectious Diseases and Paediatric Intensive Care to prepare the present recommendations with the evidence available at the time of preparing them.

negative: Real-time biomedical knowledge synthesis of the exponentially growing world wide web using unsupervised neural networks Decoding disease mechanisms for addressing unmet clinical need demands the rapid assimilation of the exponentially growing biomedical knowledge. These are either inherently unstructured and non-conducive to current computing paradigms or siloed into structured databases requiring specialized bioinformatics. Despite the recent renaissance in unsupervised neural networks for deciphering unstructured natural languages and the availability of numerous bioinformatics resources, a holistic platform for real-time synthesis of the scientific literature and seamless triangulation with deep omic insights and real-world evidence has not been advanced. Here, we introduce the nferX platform that makes the highly unstructured biomedical knowledge computable and supports the seamless visual triangulation with statistical inference from diverse structured databases. The nferX platform will accelerate and amplify the research potential of subject-matter experts as well as non-experts across the life science ecosystem (https://academia.nferx.com/).

negative: Modeling of COVID-19 Pandemic and Scenarios for Containment The impact of COVID-19 pandemic on the global health and world's economy have been profound and unseen since the Spanish flu of 1918-19. As of now, many countries have been severely affected, partly because of slow responses to the crisis, ill-preparedness of their health system, and the fragile health infrastructure and the shortage of protective equipment. This note evaluates various scenarios, based on an estimation of number of identified and unidentified infected cases, and examines the effectiveness of different policy responses to contain this pandemic. Our result, based on an estimation of the model for Iran, show that in many instances the number of unidentified cases, including asymptomatic individuals, could be much bigger than the reported numbers. The results confirm that in such circumstances, social distancing alone cannot be an effective policy unless a large portion of the population confine themselves for an extended period of time, which is not only difficult to implement, but it could also prove extremely costly and damaging to the economy. An alternative policy, this note argues, is to couple effective social distancing with extensive testing, even to those who are asymptomatic, and isolate the identified cases actively. Otherwise, many lives will be lost, and the health system will collapse, adding to the ongoing economic troubles that many countries have started to encounter.

negative: Serum neopterin for early assessment of severity of severe acute respiratory syndrome Abstract Neopterin and C-reactive protein (CRP) concentrations were determined in serum samples from 129 severe acute respiratory syndrome (SARS) patients and 156 healthy blood donors. In the patients with confirmed SARS, an early neopterin elevation was detected already at the day of onset of symptoms and rose to a maximum level of 45.0 nmol/L 3 days after the onset. All SARS patients had elevated neopterin concentrations (>10 nmol/L) within 9 days after the onset. The mean neopterin concentrations were 34.2 nmol/L in acute sera of SARS patients, 5.1 nmol/L in convalescent sera, and 6.7 nmol/L in healthy controls. In contrast, the mean CRP concentrations in both acute and convalescent sera of SARS patients were in the normal range (<10 mg/L). Serum neopterin level in SARS patients was associated with fever period and thus the clinical progression of the disease, while there was no significant correlation between the CRP level and the fever period. Serum neopterin may allow early assessment of the severity of SARS. The decrease of neopterin level was found after steroid treatment, which indicates that blood samples should be collected before steroid treatment for the neopterin measurement.

negative: Innate immunity in COVID-19 patients mediated by NKG2A receptors, and potential treatment using Monalizumab, Cholroquine, and antiviral agents Abstract Following the outbreak of a novel coronavirus (SARS-CoV-2), studies suggest that the resultant disease (COVID-19) is more severe in individuals with a weakened immune system. Cytotoxic T-cells (CTLs) and Natural Killer (NK) cells are required to generate an effective immune response against viruses, functional exhaustion of which enables disease progression. Patients with severe COVID-19 present significantly lower lymphocyte, and higher neutrophil, counts in blood. Specifically, CD8+ lymphocytes and NK cells were significantly reduced in cases of severe infection compared to patients with mild infection and healthy individuals. The NK group 2 member A (NKG2A) receptor transduces inhibitory signalling, suppressing NK cytokine secretion and cytotoxicity. Overexpression of NKG2A has been observed on CD8+ and NK cells of COVID-19 infected patients compared to healthy controls, while NKG2A overexpression also functionally exhausts CD8+ cells and NK cells, resulting in a severely compromised innate immune response. Blocking NKG2A on CD8+ cells and NK cells in cancers modulated tumor growth, restoring CD8+ T and NK cell function. A recently proposed mechanism via which SARS-CoV-2 overrides innate immune response of the host is by over-expressing NKG2A on CD+ T and NK cells, culminating in functional exhaustion of the immune response against the viral pathogen. Monalizumab is an inhibiting antibody against NKG2A which can restore the function of CD8 + T and NK cells in cancers, successfully ceasing tumor progression with no significant side effects in Phase 2 clinical trials. We hypothesize that patients with severe COVID-19 have a severely compromised innate immune response and could be treated via the use of Monalizumab, interferon α, chloroquine, and other antiviral agents.

negative: Mass Spectrometric Identification of SARS-CoV-2 Proteins from Gargle Solution Samples of COVID-19 Patients Mass spectrometry (MS) can deliver valuable diagnostic data that complements genomic information and allows us to increase our current knowledge of the COVID-19 disease caused by the SARS-CoV-2 virus. We developed a simple, MS-based method to specifically detect SARS-CoV-2 proteins from gargle solution samples of COVID-19 patients. Our protocol consists of an acetone precipitation and tryptic digestion of proteins contained within the gargle solution, followed by a targeted MS analysis. Our methodology identifies unique peptides originating from SARS-CoV-2 nucleoprotein. Building on these promising initial results, faster MS protocols can now be developed as routine diagnostic tools for COVID-19 patients. Graphical Abstract Image credit (left): Gerd Altmann, Pixabay License, https://pixabay.com/illustrations/corona-coronavirus-virus-covid-19-4959447

negative: What are the factors influencing the COVID-19 outbreak in Latin America?

negative: A retrospective study of the clinical characteristics of COVID-19 infection in 26 children Background: The outbreak of novel coronavirus pneumonia in China began in December 2019. Studies on novel coronavirus disease (COVID-19) were less based on pediatric patients. This study aimed to reveal the clinical characteristics of COVID-19 in children. Method: This study retrospectively analyzed the clinical symptoms, laboratory results, chest CT, and treatment of children with laboratory-confirmed COVID-19(ie, with samples that were positive for 2019 novel coronavirus[2019-nCoV]) who were admitted to Shenzhen Center of National Infectious Disease Clinical Medical Research from January 16 to February 8, 2020. Result: Nine patients had no obvious clinical symptom. 11 patients developed fever. Other symptoms, including cough(in eleven of seventeen patients), rhinorrhea(in two), diarrhea(in two), vomiting(in two), were also observed. A small minority of patients had lymphocytopenia. Alanine transaminase or transaminase increased in three cases. According to chest CT scan, 11 patients showed unilateral pneumonia, 8 patients had no pulmonary infiltration. No serious complications such as acute respiratory syndrome and acute lung injury occurred in all patients. Conclusion: The clinical characteristics of 2019-nCoV infection in children were different from adult. The overall condition of children were mild and have a good prognosis.

negative: A strategy targeting monocyte-macrophage differentiation to avoid pulmonary complications in SARS-Cov2 infection

negative: Intestinal protection against challenge with transmissible gastroenteritis virus of pigs immune after infection with the porcine respiratory coronavirus Abstract An infection of pigs with the porcine respiratory coronavirus (PRCV) induces antibodies which neutralize the enteropathogenic transmissible gastroenteritis virus (TGEV) and PRCV to the same titre. In the present study, 10-week-old seronegative pigs (n = 8), pigs immune following TGEV inoculation (n = 4) or pigs immune following aerosol (n = 8) or intragastric inoculation (n = 4) with PRCV were challenged with TGEV. Whereas TGEV-immune pigs were completely protected against challenge, all PRCV-immune pigs showed serological evidence of TGEV replication. Nevertheless, the aerosol or intragastric inoculation with PRCV primed the humoral immune system against TGEV and the TGEV challenge induced a secondary antibody response in most PRCV-immune pigs. Furthermore, all PRCV-immune pigs showed a decrease in the duration of the excretion of infectious TGEV (0–4 days) in comparison with the duration of the virus excretion by seronegative pigs (5–6 days).

negative: Structural Insights into 5' Flap DNA Unwinding and Incision by the Human FAN1 Dimer Human FANCD2-associated nuclease 1 (FAN1) is a DNA structure-specific nuclease involved in the processing of DNA interstrand crosslinks (ICLs). FAN1 maintains genomic stability and prevents tissue decline in multiple organs, yet it confers ICL-induced anti-cancer drug resistance in several cancer subtypes. Here we report three crystal structures of human FAN1 in complex with a 5’ flap DNA substrate, showing that two FAN1 molecules form a head-to-tail dimer to locate the lesion, orient the DNA, and unwind a 5’ flap for subsequent incision. Biochemical experiments further validate our model for FAN1 action, as structure-informed mutations that disrupt protein dimerization, substrate orientation, or flap unwinding impair the structure-specific nuclease activity. Our work elucidates essential aspects of FAN1-DNA lesion recognition and a unique mechanism of incision. These structural insights shed light on the cellular mechanisms underlying organ degeneration protection and cancer drug resistance mediated by FAN1.

negative: The prevention of nosocomial SARS-CoV2 transmission in endoscopy: a systematic review of recommendations within gastroenterology to identify best practice. Endoscopy generates aerosol droplets and fomites, thereby increasing the risk of SARS-CoV2 transmission to healthcare workers and uninfected patients within endoscopy departments. Despite the sharp rise in the incidence of COVID-19, authoritative recommendations to limit the spread of SARS-CoV2 within gastrointestinal endoscopy units are lacking. Therefore, with the primary aim of identifying best practice and scrutinizing its supporting evidence, we conducted a systematic review of literature for articles published between 1 January 2002 and 15 March 2020 in five databases relating to both the current SARS-CoV2 and the previous SARS-CoV outbreaks. Official websites for gastroenterology and endoscopy societies in the 15 most affected countries were also searched. Unfortunately, a paucity of high quality data and heterogeneity of recommendations between countries was observed. Interestingly, not all countries advocated the postponement of non-urgent or elective procedures. Recommendations for patient screening and personal protective equipment were commonly featured in all recommendations but specifics varied. Only 32% (9/28) of all gastroenterology and endoscopy societies issued guidance on endoscopy in the COVID-19 pandemic. In conclusion, stronger evidence to inform current practice and robust guidelines are urgently needed to prevent the transmission of SARS-CoV2 in gastrointestinal endoscopy departments worldwide.

negative: Protection Against Henipavirus Infection by Use of Recombinant Adeno-Associated Virus–Vector Vaccines Nipah virus (NiV) and Hendra virus (HeV) are closely related, recently emerged paramyxoviruses that are capable of causing considerable morbidity and mortality in several mammalian species, including humans. Henipavirus-specific vaccines are still commercially unavailable, and development of novel antiviral strategies to prevent lethal infections due to henipaviruses is highly desirable. Here we describe the development of adeno-associated virus (AAV) vaccines expressing the NiV G protein. Characterization of these vaccines in mice demonstrated that a single intramuscular AAV injection was sufficient to induce a potent and long-lasting antibody response. Translational studies in hamsters further demonstrated that all vaccinated animals were protected against lethal challenge with NiV. In addition, this vaccine induced a cross-protective immune response that was able to protect 50% of the animals against a challenge by HeV. This study presents a new efficient vaccination strategy against henipaviruses and opens novel perspectives on the use of AAV vectors as vaccines against emergent diseases.

negative: Comparative computational analysis of SARS-CoV-2 nucleocapsid protein epitopes in taxonomically related coronaviruses Abstract Several research lines are currently ongoing to address the multitude of facets of the pandemic COVID-19. In line with the One-Health concept, extending the target of the studies to the animals which humans are continuously interacting with may favor a better understanding of the SARS-CoV-2 biology and pathogenetic mechanisms; thus, helping to adopt the most suitable containment measures. The last two decades have already faced severe manifestations of the coronavirus infection in both humans and animals, thus, circulating epitopes from previous outbreaks might confer partial protection from SARS-CoV-2 infections. In the present study, we provide an in-silico survey of the major nucleocapsid protein epitopes and compare them with the homologues of taxonomically-related coronaviruses with tropism for animal species that are closely inter-related with the human beings population all over the world. Protein sequence alignment provides evidence of high sequence homology for some of the investigated proteins. Moreover, structural epitope mapping by homology modelling revealed a potential immunogenic value also for specific sequences scoring a lower identity with SARS-CoV-2 nucleocapsid proteins. These evidence provide a molecular structural rationale for a potential role in conferring protection from SARS-CoV-2 infection and identifying potential candidates for the development of diagnostic tools and prophylactic-oriented strategies.

negative: The impact of believing you have had COVID-19 on behaviour: Cross-sectional survey Objectives: To investigate whether people who think they have had COVID-19 are less likely to engage in social distancing measures compared with those who think they have not had COVID-19. Design: On-line cross-sectional survey. Setting: Data were collected between 20th and 22nd April. Participants: 6149 participants living in the UK aged 18 years or over. Main outcome measures: Perceived immunity to COVID-19, self-reported adherence to social distancing measures (going out for essential shopping, nonessential shopping, and meeting up with friends/family; total out-of-home activity), worry about COVID-19 and perceived risk of COVID-19 to oneself and people in the UK. Knowledge that cough and high temperature / fever are the main symptoms of COVID-19. Results: In this sample, 1493 people (24.3%) thought they had had COVID-19. Only 245 (4.0%) reported receiving a test result saying they had COVID-19. Reported test results were often incongruent with participants' belief that they had had COVID-19. People who believed that they had had COVID-19 were: more likely to agree that they had some immunity to COVID-19; less likely to report adhering to social distancing measures; less worried about COVID-19; and less likely to know that cough and high temperature / fever are two of the most common symptoms of COVID-19. Conclusions: The number of people in the UK who think they have already had COVID-19 is about twice the rate of current prevalence estimates. People who think that they have had COVID-19 may contribute to transmission of the virus through non-adherence to social distancing measures. Clear communications to this growing group are needed to explain why protective measures continue to be important and to encourage sustained adherence.

negative: Extracellular HMGB1: a therapeutic target in severe pulmonary inflammation including COVID-19? BACKGROUND: The 2019 novel coronavirus disease (COVID-19) causes for unresolved reasons acute respiratory distress syndrome in vulnerable individuals. There is a need to identify key pathogenic molecules in COVID-19-associated inflammation attainable to target with existing therapeutic compounds. The endogenous damage-associated molecular pattern (DAMP) molecule HMGB1 initiates inflammation via two separate pathways. Disulfide-HMGB1 triggers TLR4 receptors generating pro-inflammatory cytokine release. Extracellular HMGB1, released from dying cells or secreted by activated innate immunity cells, forms complexes with extracellular DNA, RNA and other DAMP or pathogen-associated molecular (DAMP) molecules released after lytic cell death. These complexes are endocytosed via RAGE, constitutively expressed at high levels in the lungs only, and transported to the endolysosomal system, which is disrupted by HMGB1 at high concentrations. Danger molecules thus get access to cytosolic proinflammatory receptors instigating inflammasome activation. It is conceivable that extracellular SARS-CoV-2 RNA may reach the cellular cytosol via HMGB1-assisted transfer combined with lysosome leakage. Extracellular HMGB1 generally exists in vivo bound to other molecules, including PAMPs and DAMPs. It is plausible that these complexes are specifically removed in the lungs revealed by a 40% reduction of HMGB1 plasma levels in arterial versus venous blood. Abundant pulmonary RAGE expression enables endocytosis of danger molecules to be destroyed in the lysosomes at physiological HMGB1 levels, but causing detrimental inflammasome activation at high levels. Stress induces apoptosis in pulmonary endothelial cells from females but necrosis in cells from males. CONCLUSION: Based on these observations we propose extracellular HMGB1 to be considered as a therapeutic target for COVID-19.

negative: Decoding SARS-CoV-2 transmission, evolution and ramification on COVID-19 diagnosis, vaccine, and medicine Tremendous effort has been given to the development of diagnostic tests, preventive vaccines, and therapeutic medicines for coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Much of this development has been based on the reference genome collected on January 5, 2020. Based on the genotyping of 6156 genome samples collected up to April 24, 2020, we report that SARS-CoV-2 has had 4459 alarmingly mutations which can be clustered into five subtypes. We introduce mutation ratio and mutation $h$-index to characterize the protein conservativeness and unveil that SARS-CoV-2 envelope protein, main protease, and endoribonuclease protein are relatively conservative, while SARS-CoV-2 nucleocapsid protein, spike protein, and papain-like protease are relatively non-conservative. In particular, the nucleocapsid protein has more than half its genes changed in the past few months, signaling devastating impacts on the ongoing development of COVID-19 diagnosis, vaccines, and drugs.

negative: Receptor-binding domain as a target for developing SARS vaccines. A decade ago, severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV) caused a global pandemic with a mortality rate of 10%. Reports of recent outbreaks of a SARS-like disease caused by Middle East respiratory syndrome coronavirus (MERS-CoV) have raised serious concerns of a possible reemergence of SARS-CoV, either by laboratory escape or the presence of a natural reservoir. Therefore, the development of effective and safe SARS vaccines is still needed. Based on our previous studies, we believe that the receptor-binding domain (RBD) in the S1 subunit of the SARS-CoV spike (S) protein is the most important target for developing a SARS vaccine. In particular, RBD of S protein contains the critical neutralizing domain (CND), which is able to induce highly potent neutralizing antibody response and cross-protection against divergent SARS-CoV strains. Furthermore, a RBD-based subunit vaccine is expected to be safer than other vaccines that may induce Th2-type immunopathology. This review will discuss key advances in the development of RBD-based SARS vaccines and the possibility of using a similar strategy to develop vaccines against MERS-CoV.

negative: How Should the Rehabilitation Community Prepare for 2019-nCoV? Abstract With the 2019-nCoV pandemic spreading quickly in USA and the world, it is urgent that the rehabilitation community quickly understands the epidemiology of the virus and what we can and must do to face this microbial adversary at the early stages of this likely long global pandemic. The 2019-nCoV is a novel virus so the majority of world’s population does not have prior immunity to it. It is more infectious and fatal than seasonal influenza, and definitive treatment and a vaccine are months away. Our arsenal against it are currently mainly social distancing and infection control measures.

negative: Virus infection, antiviral immunity, and autoimmunity. As a group of disorders, autoimmunity ranks as the third most prevalent cause of morbidity and mortality in the Western World. However, the etiology of most autoimmune diseases remains unknown. Although genetic linkage studies support a critical underlying role for genetics, the geographic distribution of these disorders as well as the low concordance rates in monozygotic twins suggest that a combination of other factors including environmental ones are involved. Virus infection is a primary factor that has been implicated in the initiation of autoimmune disease. Infection triggers a robust and usually well-coordinated immune response that is critical for viral clearance. However, in some instances, immune regulatory mechanisms may falter, culminating in the breakdown of self-tolerance, resulting in immune-mediated attack directed against both viral and self-antigens. Traditionally, cross-reactive T-cell recognition, known as molecular mimicry, as well as bystander T-cell activation, culminating in epitope spreading, have been the predominant mechanisms elucidated through which infection may culminate in an T-cell-mediated autoimmune response. However, other hypotheses including virus-induced decoy of the immune system also warrant discussion in regard to their potential for triggering autoimmunity. In this review, we discuss the mechanisms by which virus infection and antiviral immunity contribute to the development of autoimmunity.

negative: Documento de consenso sobre "tratamiento antimicrobiano de la faringoamigdalitis"

negative: 2019 novel coronavirus of pneumonia in Wuhan, China: emerging attack and management strategies An ongoing outbreak of 2019-nCoV pneumonia was first identified in Wuhan, Hubei province, China at the end of 2019. With the spread of the new coronavirus accelerating, person-to-person transmission in family homes or hospitals, and intercity spread of 2019-nCoV occurred. At least 40,261 cases confirmed, 23,589 cases suspected, 909 cases death and 3444 cases cured in China and worldwide 24 countries confirmed 383 cases being diagnosed, 1 case death in February 10th, 2020. At present, the mortality of 2019-nCoV in China is 2.3%, compared with 9.6% of SARS and 34.4% of MERS reported by WHO. It seems the new virus is not as fatal as many people thought. Chinese authorities improved surveillance network, made the laboratory be able to recognize the outbreak within a few weeks and announced the virus genome that provide efficient epidemiological control. More comprehensive information is required to understand 2019-nCoV feature, the epidemiology of origin and spreading, and the clinical phenomina. According to the current status, blocking transmission, isolation, protection, and alternative medication are the urgent management strategies against 2019-nCoV.

negative: Laboratory techniques of veterinary clinical immunology: A review Laboratory tests currently used or easily applicable in veterinary clinical immunology were reviewed in the following three categories: (1) tests detecting disorders in humoral immune response: serum protein screening tests, gammaglobulin estimation and complement testing: (2) tests detecting disorders in cellular immune response: phagocyte function tests and lymphocyte function tests; (3) tests detecting autoimmune disorders: detection of antinuclear antibodies, rheumatoid factor, autoimmune hemolytic diseases, and autoimmune organ and tissue disorders. The principles of the tests and the interpretations of the results are presented with the appropriate references.

negative: From a single host to global spread. The global mobility based modelling of the COVID-19 pandemic implies higher infection and lower detection rates than current estimates. Background: Since the outbreak of the COVID-19 pandemic, multiple efforts of modelling of the geo-temporal transmissibility of the virus have been undertaken, but none succeeded in describing the pandemic at the global level. We propose a set of parameters for the first COVID-19 Global Epidemic and Mobility Model (GLEaM). The simulation starting with just a single pre-symptomatic, yet infectious, case in Wuhan, China, results in an accurate prediction of the number of diagnosed cases after 125 days in multiple countries across three continents. Methods: We have built a modified SIR model and parameterized it analytically, according to the literature and by fitting the missing parameters to the observed dynamics of the virus spread. We compared our results with the number of diagnosed cases in sixeight selected countries which provide reliable statistics but differ substantially in terms of strength and speed of undertaken precautions. The obtained 95% confidence intervals for the predictions fit well to the empirical data. Findings: The parameters that successfully model the pandemic are: the basic reproduction number R0, ~4.4; a latent non-infectious period of 1.1. days followed by 4.6 days of the presymptomatic infectious period; the probability of developing severe symptoms, 0.01; the probability of being diagnosed when presenting severe symptoms of 0.6; the probability of diagnosis for cases with mild symptoms or asymptomatic, 0.001. Also, the higher the testing rate per country, the lower the discrepancy between data (diagnosed cases) and model. Interpretation: Parameters that successfully reproduce the observed number of cases indicate that both R0 and the prevalence of the virus might be underestimated. This is in concordance with the newest research on undocumented COVID-19 cases. Consequently, the actual mortality rate is putatively lower than estimated. Confirmation of the pandemic characteristic by further refinement of the model and screening tests is crucial for developing an effective strategy for the global epidemiological crisis.

negative: Is Global BCG Vaccination Coverage Relevant To The Progression Of SARS-CoV-2 Pandemic? Abstract The lower than expected number of SARS-CoV-2 cases in countries with fragile health systems is puzzling. Herein, we hypothesize that BCG vaccination policies adopted by different countries might influence the SARS-CoV-2 transmission patterns and/or COVID-19 associated morbidity and mortality through the vaccine’s capacity to confer heterologous protection. We also postulate that until a specific vaccine is developed, SARS-CoV-2 vulnerable populations could be immunized with BCG vaccines to attain heterologous nonspecific protection from the new coronavirus.

negative: Understanding bat SARS-like coronaviruses for the preparation of future coronavirus outbreaks — Implications for coronavirus vaccine development The severe acute respiratory syndrome coronavirus (SARS-CoV) first emerged in 2003, causing the SARS epidemic which resulted in a 10% fatality rate. The advancements in metagenomic techniques have allowed the identification of SARS-like coronaviruses (SL-CoVs) sequences that share high homology to the human SARS-CoV epidemic strains from wildlife bats, presenting concrete evidence that bats are the origin and natural reservoir of SARS-CoV. The application of reverse genetics further enabled that characterization of these bat CoVs and the prediction of their potential to cause disease in humans. The knowledge gained from such studies is valuable in the surveillance and preparation of a possible future outbreak caused by a spill-over of these bat SL-CoVs.

negative: Immunity to PRRSV: Double-edged sword Abstract The immune system is a double-edged sword for porcine reproductive and respiratory syndrome virus (PRRSV) infection. On one edge PRRSV has a predilection for immune cells and the disease manifestations can be linked directly to changes in the immune system. PRRSV appears to replicate extensively, if not exclusively, in cells of the immune lineage, notably macrophages; the direct replication of which may lead to immunosuppression, precipitate secondary infection and/or mediate disease. On the other edge, the virus stimulates immunity post-infection that protects an animal from re-infection. A vast array of structural and functionally distinct antibody specific to PRRSV are generated following infection or vaccination. Discrete populations of functional antibodies appear at different times and possibly reflect reactivity to different PRRSV polypeptides. Cell-mediated immune responses specific to PRRSV can be detected in various exposed pigs as well. Thus, the immune system appears to be intimately involved in both the disease process and protection from disease. It is unclear at this state of understanding what immune compartment provides protective immunity. Is it humoral (i.e. antibodies), selective functionally distinct populations of antibodies specific for selected PRRSV polypeptides or is cellular immunity essential for protection, or both. This review will attempt to summarize the current state of knowledge of the complex interaction of the immune system and PRRSV.

negative: Microneedle array delivered recombinant coronavirus vaccines: Immunogenicity and rapid translational development BACKGROUND: Coronaviruses pose a serious threat to global health as evidenced by Severe Acute Respiratory Syndrome (SARS), Middle East Respiratory Syndrome (MERS), and COVID-19. SARS Coronavirus (SARS-CoV), MERS Coronavirus (MERS-CoV), and the novel coronavirus, previously dubbed 2019-nCoV, and now officially named SARS-CoV-2, are the causative agents of the SARS, MERS, and COVID-19 disease outbreaks, respectively. Safe vaccines that rapidly induce potent and long-lasting virus-specific immune responses against these infectious agents are urgently needed. The coronavirus spike (S) protein, a characteristic structural component of the viral envelope, is considered a key target for vaccines for the prevention of coronavirus infection. METHODS: We first generated codon optimized MERS-S1 subunit vaccines fused with a foldon trimerization domain to mimic the native viral structure. In variant constructs, we engineered immune stimulants (RS09 or flagellin, as TLR4 or TLR5 agonists, respectively) into this trimeric design. We comprehensively tested the pre-clinical immunogenicity of MERS-CoV vaccines in mice when delivered subcutaneously by traditional needle injection, or intracutaneously by dissolving microneedle arrays (MNAs) by evaluating virus specific IgG antibodies in the serum of vaccinated mice by ELISA and using virus neutralization assays. Driven by the urgent need for COVID-19 vaccines, we utilized this strategy to rapidly develop MNA SARS-CoV-2 subunit vaccines and tested their pre-clinical immunogenicity in vivo by exploiting our substantial experience with MNA MERS-CoV vaccines. FINDINGS: Here we describe the development of MNA delivered MERS-CoV vaccines and their pre-clinical immunogenicity. Specifically, MNA delivered MERS-S1 subunit vaccines elicited strong and long-lasting antigen-specific antibody responses. Building on our ongoing efforts to develop MERS-CoV vaccines, promising immunogenicity of MNA-delivered MERS-CoV vaccines, and our experience with MNA fabrication and delivery, including clinical trials, we rapidly designed and produced clinically-translatable MNA SARS-CoV-2 subunit vaccines within 4 weeks of the identification of the SARS-CoV-2 S1 sequence. Most importantly, these MNA delivered SARS-CoV-2 S1 subunit vaccines elicited potent antigen-specific antibody responses that were evident beginning 2 weeks after immunization. INTERPRETATION: MNA delivery of coronaviruses-S1 subunit vaccines is a promising immunization strategy against coronavirus infection. Progressive scientific and technological efforts enable quicker responses to emerging pandemics. Our ongoing efforts to develop MNA-MERS-S1 subunit vaccines enabled us to rapidly design and produce MNA SARS-CoV-2 subunit vaccines capable of inducing potent virus-specific antibody responses. Collectively, our results support the clinical development of MNA delivered recombinant protein subunit vaccines against SARS, MERS, COVID-19, and other emerging infectious diseases.

negative: Broad-spectrum coronavirus antiviral drug discovery Introduction: The highly pathogenic coronaviruses severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV) are lethal zoonotic viruses that have emerged into human populations these past 15 years. These coronaviruses are associated with novel respiratory syndromes that spread from person-to-person via close contact, resulting in high morbidity and mortality caused by the progression to Acute Respiratory Distress Syndrome (ARDS). Areas covered: The risks of re-emergence of SARS-CoV from bat reservoir hosts, the persistence of MERS-CoV circulation, and the potential for future emergence of novel coronaviruses indicate antiviral drug discovery will require activity against multiple coronaviruses. In this review, approaches that antagonize viral nonstructural proteins, neutralize structural proteins, or modulate essential host elements of viral infection with varying levels of efficacy in models of highly pathogenic coronavirus disease are discussed. Expert opinion: Treatment of SARS and MERS in outbreak settings has focused on therapeutics with general antiviral activity and good safety profiles rather than efficacy data provided by cellular, rodent, or nonhuman primate models of highly pathogenic coronavirus infection. Based on lessons learned from SARS and MERS outbreaks, lack of drugs capable of pan-coronavirus antiviral activity increases the vulnerability of public health systems to a highly pathogenic coronavirus pandemic.

negative: Emergence of RBD mutations in circulating SARS-CoV-2 strains enhancing the structural stability and human ACE2 receptor affinity of the spike protein A novel coronavirus SARS-CoV-2 is associated with the current global pandemic of Coronavirus Disease 2019 (COVID-19). Spike protein receptor-binding domain (RBD) of SARS-CoV-2 is the critical determinant of viral tropism and infectivity. To investigate whether the mutations in the RBD have altered the receptor binding affinity and caused these strains more infectious, we performed molecular dynamics simulations of the binding affinity between the mutant SARS-CoV-2 RBDs to date and the human ACE2 receptor. Among 1609 genomes of global SARS-CoV-2 strains, 32 non-synonymous RBD mutants were identified and clustered into 9 mutant types under high positive selection pressure. Three mutant types (V367F, W436R, and D364Y) emerging in Wuhan, Shenzhen, Hong Kong, and France, displayed higher human ACE2 affinity, and probably higher infectivity. This is due to the enhanced structural stabilization of the RBD beta-sheet scaffold. High frequencies of RBD mutations were identified: V367F from five France and one Hong Kong mutants, 13 V483A and 7 G476S mutants from the U.S.A. This suggested they originated as novel sub-lineages. The enhancement of the binding affinity of the mutant type (V367F) was further validated by the receptor-ligand binding ELISA assay. The molecular dynamics simulations also indicated that it would be difficult for bat SARS-like CoV to infect humans. However, the pangolin CoV is potentially infectious to humans. The analysis of critical RBD mutations provides further insights into the evolutionary history of SARS-CoV-2 under high selection pressure. An enhancement of the SARS-CoV-2 binding affinity to human ACE2 receptor reveals higher infectivity of the mutant strains. Importance A novel coronavirus SARS-CoV-2 has caused the pandemic of COVID-19. The origin of SARS-CoV-2 was associated with zoonotic infections. The spike protein receptor-binding domain (RBD) is identified as the critical determinant of viral tropism and infectivity. Thus, whether the mutations in the RBD of the circulating SARS-CoV-2 strains have altered the receptor binding affinity and caused these strains more infectious, should be paid more attentions to. Here, 32 non-synonymous RBD mutants were identified and clustered into 9 mutant types under high positive selection pressure, suggesting they originated as novel sub-lineages. Three mutant types displayed higher human ACE2 affinity, and probably higher infectivity, one of which (V367F) was validated by wet bench. The RBD mutation analysis provides insights into SARS-CoV-2 evolution. The emergence of RBD mutations with increased human ACE2 affinity reveals higher risk of severe morbidity and mortality during a sustained COVID-19 pandemic, particularly if no effective precautions are implemented.

negative: Advances in peste des petits ruminants vaccines Abstract Peste des petits ruminants (PPR) is a highly contagious disease of small ruminants that leads to high morbidity and mortality thereby results in devastating economic consequences to the livestock industry. PPR is currently endemic across most parts of Asia and Africa, the two regions with the highest concentration of poor people in the world. Sheep and goats in particularly contribute significantly towards the upliftment of livelihood of the poor and marginal farmers in these regions. In this context, PPR directly affecting the viability of sheep and goat husbandry has emerged as a major hurdle in the development of these regions. The control of PPR in these regions could significantly contribute to poverty alleviation, therefore, the Office International des Epizooties (OIE) and Food and Agricultural Organization (FAO) have targeted the control and eradication of PPR by 2030 a priority. In order to achieve this goal, a potent, safe and efficacious live-attenuated PPR vaccine with long-lasting immunity is available for immunoprophylaxis. However, the live-attenuated PPR vaccine is thermolabile and needs maintenance of an effective cold chain to deliver into the field. In addition, the infected animals cannot be differentiated from vaccinated animals. To overcome these limitations, some recombinant vaccines have been developed. This review comprehensively describes about the latest developments in PPR vaccines.

negative: Initial impacts of global risk mitigation measures taken during the combatting of the COVID-19 pandemic Abstract This paper presents an analysis of risk mitigation measures taken by countries around the world facing the current COVID-19 outbreak. In light of the current pandemic the authors collated and clustered (using harmonised terminology) the risk mitigation measures taken around the globe in the combat to contain, and since March 11 2020, to limit the spread of the SARS-CoV-2 virus known to cause the Coronavirus disease 2019 (COVID-19). This overview gathers lessons learnt, providing an update on the current knowledge for authorities, sectors and first responders on the effectiveness of said measures, and may allow enhanced prevention, preparedness and response for future outbreaks. Various measures such as mobility restrictions, physical distancing, hygienic measures, socio-economic restrictions, communication and international support mechanisms have been clustered and are reviewed in terms of the nature of the actions taken and their qualitative early-perceived impact. At the time of writing, it is still too premature to express the quantitative effectiveness of each risk mitigation cluster, but it seems that the best mitigation results are reported when applying a combination of voluntary and enforceable measures.

negative: Finding equipoise: CEPI revises its equitable access policy Launched at Davos in January 2017 with funding from sovereign investors and philanthropic institutions, the Coalition for Epidemic Preparedness Innovations (CEPI) is an innovative partnership between public, private, philanthropic, and civil organisations whose mission is to stimulate, finance and co-ordinate vaccine development against diseases with epidemic potential in cases where market incentives fail. As of December 2019, CEPI has committed to investing up to $706 million in vaccine development. This includes 19 vaccine candidates against its priority pathogens (Lassa fever virus, Middle East respiratory syndrome coronavirus, Nipah virus, Chikungunya, Rift Valley fever) and three vaccine platforms to develop vaccines against Disease X, a novel or unanticipated pathogen. As an entity largely supported by public funds, ensuring equitable access to vaccines whose development it supports in low- and middle-income countries is CEPI’s primary focus. CEPI developed an initial equitable access policy shortly after its formation, with key stakeholders expressing strong views about its content and prescriptive nature. The CEPI board instructed that it be revisited after a year. This paper describes the process of revising the policy, and how key issues were resolved. CEPI will continue to take an iterative, rather than prescriptive, approach to its policy—one that reflects the needs of multiple stakeholders and ensures it can meet its equitable access goals.

negative: Cannabinoid Receptor Type 2: A Possible Target in SARS-CoV-2 (CoV-19) Infection? In late December 2019, a novel coronavirus (SARS-CoV-2 or CoV-19) appeared in Wuhan, China, causing a global pandemic. SARS-CoV-2 causes mild to severe respiratory tract inflammation, often developing into lung fibrosis with thrombosis in pulmonary small vessels and causing even death. COronaVIrus Disease (COVID-19) patients manifest exacerbated inflammatory and immune responses, cytokine storm, prevalence of pro-inflammatory M1 macrophages and increased levels of resident and circulating immune cells. Men show higher susceptibility to SARS-CoV-2 infection than women, likely due to estrogens production. The protective role of estrogens, as well as an immune-suppressive activity that limits the excessive inflammation, can be mediated by cannabinoid receptor type 2 (CB2). The role of this receptor in modulating inflammation and immune response is well documented in fact in several settings. The stimulation of CB2 receptors is known to limit the release of pro-inflammatory cytokines, shift the macrophage phenotype towards the anti-inflammatory M2 type and enhance the immune-modulating properties of mesenchymal stromal cells. For these reasons, we hypothesize that CB2 receptor can be a therapeutic target in COVID-19 pandemic emergency.

negative: Anti-severe acute respiratory syndrome coronavirus spike antibodies trigger infection of human immune cells via a pH- and cysteine protease-independent FcγR pathway. Public health measures successfully contained outbreaks of the severe acute respiratory syndrome coronavirus (SARS-CoV) infection. However, the precursor of the SARS-CoV remains in its natural bat reservoir, and reemergence of a human-adapted SARS-like coronavirus remains a plausible public health concern. Vaccination is a major strategy for containing resurgence of SARS in humans, and a number of vaccine candidates have been tested in experimental animal models. We previously reported that antibody elicited by a SARS-CoV vaccine candidate based on recombinant full-length Spike-protein trimers potentiated infection of human B cell lines despite eliciting in vivo a neutralizing and protective immune response in rodents. These observations prompted us to investigate the mechanisms underlying antibody-dependent enhancement (ADE) of SARS-CoV infection in vitro. We demonstrate here that anti-Spike immune serum, while inhibiting viral entry in a permissive cell line, potentiated infection of immune cells by SARS-CoV Spike-pseudotyped lentiviral particles, as well as replication-competent SARS coronavirus. Antibody-mediated infection was dependent on Fcγ receptor II but did not use the endosomal/lysosomal pathway utilized by angiotensin I converting enzyme 2 (ACE2), the accepted receptor for SARS-CoV. This suggests that ADE of SARS-CoV utilizes a novel cell entry mechanism into immune cells. Different SARS vaccine candidates elicit sera that differ in their capacity to induce ADE in immune cells despite their comparable potency to neutralize infection in ACE2-bearing cells. Our results suggest a novel mechanism by which SARS-CoV can enter target cells and illustrate the potential pitfalls associated with immunization against it. These findings should prompt further investigations into SARS pathogenesis.

negative: Is there an ideal animal model for SARS? The outbreak of severe acute respiratory syndrome (SARS) in 2003 was controlled by public health measures at a time when specific interventions such as antiviral drugs, vaccines and immunotherapy were not available. Since then, several animal models have been developed for the study of SARS and, although no model replicates the human disease in all aspects, the use of animal models for SARS has led to the establishment of several important principles for vaccine and immunotherapy. Consistency and reproducibility of findings in a given model must be demonstrated to establish the superiority of one model over others. Here, we suggest aspects of an ideal animal model for studies of SARS pathogenesis and vaccine development and present our assessment of the strengths and limitations of the current animal models for SARS.

negative: Trends of SARS-CoV-2 infection worldwide: Role of population density, age structure, and climate on transmission and case fatality Introduction The disease transmission pattern of COVID19 is highly heterogeneous, which suggests that the pandemic maybe driven by complex factors, which may include habitat suitability, region specific human mobility, and transmission related to susceptibility. The purpose of this study was to examine the effects of different spatial and demographic factors on COVID19 transmission and case fatality worldwide. Methods We assessed SARS CoV2 virus transmission and COVID19 related fatalities in 50 countries in all continents of the globe. Data from the COVID19 data repository of the Johns Hopkins Center for Systems Science and Engineering, the European center for disease control and prevention, and the World Health Organization were used to obtain the daily number of cases and organize the incidence data. Disease spread, was assessed using the reproduction number of the disease across the sampled countries. R0 package of R statistical software was used to estimate the reproduction number of the COVID19 using the exponential growth method. After computing the reproductive number of each country in the study, a multiple linear regression model was fitted by taking the R0 value as dependent variable, and latitude and population density as an independent variable. Disease severity was analyzed using the case fatality ratio of COVID19. The proportion of deaths to the total numbers of cases was meta analyzed using metaphor package of R statistical software using random effect inverse variance weighting to come up with the case fatality ratio. Results We found no statistically significant association between disease spread and latitude or population density. The regression model analysis that accounted for age, population density and latitude showed that age distribution remains an important driver shaping the current distribution of COVID19 cases. The relative frequency of people above 65 years old was positively correlated with the cumulative numbers of COVID19 cases as well as case fatality ratio in each country. The multiple linear regression model fitted between CFR and the three major covariates showed that, the demographic distribution of the sampled countries is strongly associated with the case fatality ratio. An increase in the elderly population proportion by 1 percent was associated with an increase in CFR by 0.32. Correlation with proportion of populations over 65 years old is concordant with the previous findings relationship between case fatality ratio and patient age. Conclusion This analysis provides important information that can inform the decisions of local and global health authorities. Particularly, as our study confirms that death and severity of COVID19 are associated with age, in countries with the biggest outbreaks, strategies must be employed to ensure that high risk groups, such as old people received adequate protection from COVID19.

negative: Pathogenicity studies of feline coronavirus isolates 79-1146 and 79-1683. Two feline coronavirus isolates were characterized by their disease-causing potential in cats. The 79-1683 feline coronavirus isolate caused an inapparent-to-mild enteritis when given oronasally to specific-pathogen-free kittens and was not a cause of feline infectious peritonitis (FIP). Target tissues for the virus were the mature apical epithelium of the small intestine, mesenteric lymph nodes, tonsils, thymus, and (to a lesser extent) the lungs. Inoculated kittens shed high numbers of virus in their feces for 14 to 17 days, but remained infectious to susceptible kittens for longer periods of time, as evidenced by contact-exposure studies. Because the 79-1683 isolate induced only enteritis, it was designated feline enteric coronavirus (FECV) 79-1683. The 79-1146 feline coronavirus isolate induced effusive abdominal FIP in specific-pathogen-free kittens after oronasal and intraperitoneal inoculation. Clinical signs of disease appeared within 12 to 14 days in almost all inoculated kittens. Because this isolate caused FIP, it was designated FIP virus (FIPV) 79-1146. Cross-protective immunity was not induced by the various coronavirus infections. Kittens preimmunized with the UCD strain of FECV (FECV-UCD) or with FECV-79-1683 were not immune to infection with FIPV-79-1146. Likewise, kittens previously inoculated with FECV-79-1683 were not immune to infection with FIPV-UCD1. In fact, preexisting heterologous FECV-79-1683 immunity often accelerated and enhanced the severity of disease caused by inoculation with FIPV-UCD1.(ABSTRACT TRUNCATED AT 250 WORDS)

negative: Dendritic Cells in the Cross Hair for the Generation of Tailored Vaccines Vaccines represent the discovery of utmost importance for global health, due to both prophylactic action to prevent infections and therapeutic intervention in neoplastic diseases. Despite this, current vaccination strategies need to be refined to successfully generate robust protective antigen-specific memory immune responses. To address this issue, one possibility is to exploit the high efficiency of dendritic cells (DCs) as antigen-presenting cells for T cell priming. DCs functional plasticity allows shaping the outcome of immune responses to achieve the required type of immunity. Therefore, the choice of adjuvants to guide and sustain DCs maturation, the design of multifaceted vehicles, and the choice of surface molecules to specifically target DCs represent the key issues currently explored in both preclinical and clinical settings. Here, we review advances in DCs-based vaccination approaches, which exploit direct in vivo DCs targeting and activation options. We also discuss the recent findings for efficient antitumor DCs-based vaccinations and combination strategies to reduce the immune tolerance promoted by the tumor microenvironment.

negative: Exposure of epitope residues on the outer face of the chikungunya virus envelope trimer determines antibody neutralizing efficacy. UNLABELLED Chikungunya virus (CHIKV) is a reemerging alphavirus that causes a debilitating arthritic disease and infects millions of people and for which no specific treatment is available. Like many alphaviruses, the structural targets on CHIKV that elicit a protective humoral immune response in humans are poorly defined. Here we used phage display against virus-like particles (VLPs) to isolate seven human monoclonal antibodies (MAbs) against the CHIKV envelope glycoproteins E2 and E1. One MAb, IM-CKV063, was highly neutralizing (50% inhibitory concentration, 7.4 ng/ml), demonstrated high-affinity binding (320 pM), and was capable of therapeutic and prophylactic protection in multiple animal models up to 24 h postexposure. Epitope mapping using a comprehensive shotgun mutagenesis library of 910 mutants with E2/E1 alanine mutations demonstrated that IM-CKV063 binds to an intersubunit conformational epitope on domain A, a functionally important region of E2. MAbs against the highly conserved fusion loop have not previously been reported but were also isolated in our studies. Fusion loop MAbs were broadly cross-reactive against diverse alphaviruses but were nonneutralizing. Fusion loop MAb reactivity was affected by temperature and reactivity conditions, suggesting that the fusion loop is hidden in infectious virions. Visualization of the binding sites of 15 different MAbs on the structure of E2/E1 revealed that all epitopes are located at the membrane-distal region of the E2/E1 spike. Interestingly, epitopes on the exposed topmost and outer surfaces of the E2/E1 trimer structure were neutralizing, whereas epitopes facing the interior of the trimer were not, providing a rationale for vaccine design and therapeutic MAb development using the intact CHIKV E2/E1 trimer. IMPORTANCE CHIKV is the most important alphavirus affecting humans, resulting in a chronic arthritic condition that can persist for months or years. In recent years, millions of people have been infected globally, and the spread of CHIKV to the Americas is now beginning, with over 100,000 cases occurring in the Caribbean within 6 months of its arrival. Our study reports on seven human MAbs against the CHIKV envelope, including a highly protective MAb and rarely isolated fusion loop MAbs. Epitope mapping of these MAbs demonstrates how some E2/E1 epitopes are exposed or hidden from the human immune system and suggests a structural mechanism by which these MAbs protect (or fail to protect) against CHIKV infection. Our results suggest that the membrane-distal end of CHIKV E2/E1 is the primary target for the humoral immune response to CHIKV, and antibodies targeting the exposed topmost and outer surfaces of the E2/E1 trimer determine the neutralizing efficacy of this response.

negative: Noninvasive ventilation in acute respiratory failure due to H1N1 influenza: A word of caution

negative: Identification of type-specific and cross-reactive neutralizing conformational epitopes on the major capsid protein of human papillomavirus type 31 The majority of the neutralizing epitopes of papillomaviruses (PV) are conformation-specific and have not been fully characterised. Studies have, to date, been limited to a few HPV types only. We analysed the epitopes on the major capsid protein (L1) of Human papillomavirus (HPV) type 31 using monoclonal antibodies (MAbs) generated against HPV-31 virus-like particles (VLPs). The type-specific MAbs against HPV-31 were all found to be neutralizing and recognized conformation-dependent epitopes. Two other MAbs directed against a conformational epitope were found to be cross-reactive with other HPV types, and one of them was found to be cross-neutralizing. Cross-reactive antibodies were further investigated using wild-type HPV-16 L1 VLPs and two mutants. The results obtained suggested the existence of a cross-neutralizing conformational epitope at the N-terminal part of the FG loop of the major capsid protein, and the other four cross-reactive MAbs recognized epitopes also located at the N-terminal part of the FG loop.

negative: Chapter 46 Harnessing γδ T Cells as Natural Immune Modulators Abstract There has been renewed interest in harnessing the power of the immune system as a countermeasure against infectious pathogens and cancers. One immune cell target in the development of these approaches is the γδ T cell. These cells are involved in innate and adaptive immune responses against infectious agents and cancers, and they migrate to, and reside in, mucosal tissues. γδ T cells exhibit a broad array of natural (or constitutive) and induced effector functions, including antigen presentation, that can be fine-tuned depending on their stimulation. They express unique antigen receptors as well as nonantigen, innate immune type surface receptors that can be targeted. In this chapter, we will review the biology and the basis for use of γδ T cells as a therapeutic target. We will then summarize novel plant- and microbe-derived materials that enhance γδ T cell activity in animal models and humans that can be used as a new strategy for mucosal vaccine development.

negative: A mathematical design of vector vaccine against autoimmune disease Abstract Viruses have been implicated in the initiation, progression, and exacerbation of several human autoimmune diseases. Evidence also exists that viruses can protect against autoimmune disease. Several proposed mechanisms explain the viral effects. One mechanism is “molecular mimicry” which represents a shared immunologic epitope with a microbe and the host. We consider, using a simple mathematical model, whether and how a viral infection with molecular mimicry can be beneficial or detrimental for autoimmune disease. Furthermore, we consider the possibility of development of a vector therapeutic vaccine that can relieve autoimmune disease symptoms. Our findings demonstrate that vaccine therapy success necessitates (i) appropriate immune response function, (ii) appropriate affinities with self and non-self antigen, and (iii) a replicative vector vaccine. Moreover, the model shows that the viral infection can cause autoimmune relapses.

negative: Skin Delivery of Modified Vaccinia Ankara Viral Vectors Generates Superior T Cell Immunity Against a Respiratory Viral Challenge Modified Vaccinia Ankara (MVA) was recently approved as a Smallpox vaccine. Transmission of Variola is by respiratory droplets, and MVA delivered by skin scarification (s.s.) protected mice far more effectively against lethal respiratory challenge with VACV than any other route of delivery, and at much lower doses. Comparisons of s.s. with intradermal, subcutaneous or intramuscular routes showed that MVAOVA s.s.-generated T cells were both more abundant and transcriptionally distinct. MVAOVA s.s. produced greater numbers of lung Ova-specific CD8+ TRM and was superior in protecting mice against lethal VACVOVA respiratory challenge. Nearly as many lung TRM were generated with MVAOVA s.s. compared to direct pulmonary immunization with MVAOVA, and both routes vaccination protected mice against lethal pulmonary challenge with VACVOVA. Strikingly, MVAOVA s.s.-generated effector T cells exhibited overlapping gene transcriptional profiles to those generated via direct pulmonary immunization. Overall, our data suggest that heterologous MVA vectors delivered via s.s. are uniquely well-suited as vaccine vectors for respiratory pathogens like COVID-19. In addition, MVA delivered via s.s. could represent a more effective dose-sparing smallpox vaccine.

negative: Persistence of intestinal SARS-CoV-2 infection in patients with COVID-19 leads to re-admission after pneumonia resolved Abstract The current reports of COVID-19 focus on the respiratory system, but intestinal infections caused by SARS-CoV-2 are also worthy of attention. Here we report persistence of intestinal SARS-CoV-2 infection in three cases with COVID-19 leads to re-admission after pneumonia resolved.

negative: Concerns for activated breathing control (ABC) with breast cancer in the era of COVID-19: Maximizing infection control while minimizing heart dose

negative: Interplay of host regulatory network on SARS-CoV-2 binding and replication machinery We dissect the mechanism of SARS-CoV-2 in human lung host from the initial phase of receptor binding to viral replication machinery. We constructed two independent lung protein interactome to reveal the signaling process on receptor activation and host protein hijacking machinery in the pathogenesis of virus. Further, we test the functional role of the hubs derived from both interactome. Most hubs proteins were differentially regulated on SARS-CoV-2 infection. Also, the proteins of viral replication hubs were related with cardiovascular disease, diabetes and hypertension confirming the vulnerability and severity of infection in the risk individual. Additionally, the hub proteins were closely linked with other viral infection, including MERS and HCoVs which suggest similar infection pattern in SARS-CoV-2. We identified five interconnecting cascades between hubs of both networks that show the preparation of optimal environment in the host for viral replication process upon receptor attachment. Interestingly, we propose that seven potential miRNAs, targeting the intermediate phase that connects receptor and viral replication process a better choice as a drug for SARS-CoV-2.

negative: SARS-CoV-2 Cell Entry Depends on ACE2 and TMPRSS2 and Is Blocked by a Clinically Proven Protease Inhibitor The recent emergence of the novel, pathogenic SARS-coronavirus 2 (SARS-CoV-2) in China and its rapid national and international spread pose a global health emergency. Cell entry of coronaviruses depends on binding of the viral spike (S) proteins to cellular receptors and on S protein priming by host cell proteases. Unravelling which cellular factors are used by SARS-CoV-2 for entry might provide insights into viral transmission and reveal therapeutic targets. Here, we demonstrate that SARS-CoV-2 uses the SARS-CoV receptor ACE2 for entry and the serine protease TMPRSS2 for S protein priming. A TMPRSS2 inhibitor approved for clinical use blocked entry and might constitute a treatment option. Finally, we show that the sera from convalescent SARS patients cross-neutralized SARS-2-S-driven entry. Our results reveal important commonalities between SARS-CoV-2 and SARS-CoV infection and identify a potential target for antiviral intervention.

negative: The pivotal link between ACE2 deficiency and SARS-CoV-2 infection Abstract Angiotensin converting enzyme-2 (ACE2) receptors mediate the entry into the cell of three strains of coronavirus: SARS-CoV, NL63 and SARS-CoV-2. ACE2 receptors are ubiquitous and widely expressed in the heart, vessels, gut, lung (particularly in type 2 pneumocytes and macrophages), kidney, testis and brain. ACE2 is mostly bound to cell membranes and only scarcely present in the circulation in a soluble form. An important salutary function of membrane-bound and soluble ACE2 is the degradation of angiotensin II to angiotensin1-7. Consequently, ACE2 receptors limit several detrimental effects resulting from binding of angiotensin II to AT1 receptors, which include vasoconstriction, enhanced inflammation and thrombosis. The increased generation of angiotensin1-7 also triggers counter-regulatory protective effects through binding to G-protein coupled Mas receptors. Unfortunately, the entry of SARS-CoV2 into the cells through membrane fusion markedly down-regulates ACE2 receptors, with loss of the catalytic effect of these receptors at the external site of the membrane. Increased pulmonary inflammation and coagulation have been reported as unwanted effects of enhanced and unopposed angiotensin II effects via the ACE→Angiotensin II→AT1 receptor axis. Clinical reports of patients infected with SARS-CoV-2 show that several features associated with infection and severity of the disease (i.e., older age, hypertension, diabetes, cardiovascular disease) share a variable degree of ACE2 deficiency. We suggest that ACE2 down-regulation induced by viral invasion may be especially detrimental in people with baseline ACE2 deficiency associated with the above conditions. The additional ACE2 deficiency after viral invasion might amplify the dysregulation between the ‘adverse’ ACE→Angiotensin II→AT1 receptor axis and the ‘protective’ ACE2→Angiotensin1-7→Mas receptor axis. In the lungs, such dysregulation would favor the progression of inflammatory and thrombotic processes triggered by local angiotensin II hyperactivity unopposed by angiotensin1-7. In this setting, recombinant ACE2, angiotensin1-7 and angiotensin II type 1 receptor blockers could be promising therapeutic approaches in patients with SARS-CoV-2 infection.

negative: Effects of a SARS-associated coronavirus vaccine in monkeys The causative agent of severe acute respiratory syndrome (SARS) has been identified as a new type of coronavirus. Here, we have investigated the ability of adenoviral delivery of codon-optimised SARS-CoV strain Urbani structural antigens spike protein S1 fragment, membrane protein, and nucleocapsid protein to induce virus-specific broad immunity in rhesus macaques. We immunised rhesus macaques intramuscularly with a combination of the three Ad5-SARS-CoV vectors or a control vector and gave a booster vaccination on day 28. The vaccinated animals all had antibody responses against spike protein S1 fragment and T-cell responses against the nucleocapsid protein. All vaccinated animals showed strong neutralising antibody responses to SARS-CoV infection in vitro. These results show that an adenoviral-based vaccine can induce strong SARS-CoV-specific immune responses in the monkey, and hold promise for development of a protective vaccine against the SARS causal agent.

negative: Cross-reactive antibodies enhance live attenuated virus infection for increased immunogenicity Vaccination has achieved remarkable successes in the control of childhood viral diseases. To control emerging infections, however, vaccines will need to be delivered to older individuals who, unlike infants, probably have had prior infection or vaccination with related viruses and thus have cross-reactive antibodies against the vaccines. Whether and how these cross-reactive antibodies impact live attenuated vaccination efficacy is unclear. Using an open-label randomized trial design, we show that subjects with a specific range of cross-reactive antibody titres from a prior inactivated Japanese encephalitis vaccination enhanced yellow fever (YF) immunogenicity upon YF vaccination. Enhancing titres of cross-reactive antibodies prolonged YF vaccine viraemia, provoked greater pro-inflammatory responses, and induced adhesion molecules intrinsic to the activating Fc-receptor signalling pathway, namely immune semaphorins, facilitating immune cell interactions and trafficking. Our findings clinically demonstrate antibody-enhanced infection and suggest that vaccine efficacy could be improved by exploiting cross-reactive antibodies. SUPPLEMENTARY INFORMATION: The online version of this article (doi:10.1038/nmicrobiol.2016.164) contains supplementary material, which is available to authorized users.

negative: Ferret Coronavirus-Associated Diseases A novel coronavirus of ferrets was first described in 1993. This coronavirus caused an enteric disease called epizootic catarrhal enteritis (ECE). Recently, a ferret systemic coronavirus (FRSCV)-associated disease was discovered. This new systemic disease resembles the dry form of feline infectious peritonitis (FIP) and has been reported in the United States and Europe. This article addresses the clinical signs, pathology, pathogenesis, diagnosis, treatment, and prevention of this ferret FIP-like disease.

negative: A mechanistic population balance model to evaluate the impact of interventions on infectious disease outbreaks: Case for COVID19 Infectious diseases, especially when new and highly contagious, could be devastating producing epidemic outbreaks and pandemics. Predicting the outcomes of such events in relation to possible interventions is crucial for societal and healthcare planning and forecasting of resource needs. Deterministic and mechanistic models can capture the main known phenomena of epidemics while also allowing for a meaningful interpretation of results. In this work a deterministic mechanistic population balance model was developed. The model describes individuals in a population by infection stage and age group. The population is treated as in a close well mixed community with no migrations. Infection rates and clinical and epidemiological information govern the transitions between stages of the disease. The present model provides a steppingstone to build upon and its current low complexity retains accessibility to non experts and policy makers to comprehend the variables and phenomena at play. The impact of specific interventions on the outbreak time course, number of cases and outcome of fatalities were evaluated including that of available critical care. Data available from the COVID19 outbreak as of early April 2020 was used. Key findings in our results indicate that (i) universal social isolation measures appear effective in reducing total fatalities only if they are strict and the number of daily social interactions is reduced to very low numbers; (ii) selective isolation of only the elderly (at higher fatality risk) appears almost as effective in reducing total fatalities but at a much lower economic damage; (iii) an increase in the number of critical care beds could save up to eight lives per extra bed in a million population with the current parameters used; (iv) the use of protective equipment (PPE) appears effective to dramatically reduce total fatalities when implemented extensively and in a high degree; (v) infection recognition through random testing of the population, accompanied by subsequent (self) isolation of infected aware individuals, can dramatically reduce the total fatalities but only if conducted extensively to almost the entire population and sustained over time; (vi) ending isolation measures while R0 values remain above 1.0 (with a safety factor) renders the isolation measures useless and total fatality numbers return to values as if nothing was ever done; (vii) ending the isolation measures for only the population under 60 y/o at R0 values still above 1.0 increases total fatalities but only around half as much as if isolation ends for everyone; (viii) a threshold value, equivalent to that for R0, appears to exist for the daily fatality rate at which to end isolation measures, this is significant as the fatality rate is (unlike R0) very accurately known. Any interpretation of these results for the COVID19 outbreak predictions and interventions should be considered only qualitatively at this stage due to the low confidence (lack of complete and valid data) on the parameter values available at the time of writing. Any quantitative interpretation of the results must be accompanied with a critical discussion in terms of the model limitations and its frame of application.

negative: Single-Dose, Intranasal Immunization with Recombinant Parainfluenza Virus 5 Expressing Middle East Respiratory Syndrome Coronavirus (MERS-CoV) Spike Protein Protects Mice from Fatal MERS-CoV Infection Middle East respiratory syndrome coronavirus (MERS-CoV) can cause severe and fatal acute respiratory disease in humans and remains endemic in the Middle East since first being identified in 2012. There are currently no approved vaccines or therapies available for MERS-CoV. In this study, we evaluated parainfluenza virus 5 (PIV5)-based vaccine expressing the MERS-CoV envelope spike protein (PIV5/MERS-S) in a human DPP4 knockin C57BL/6 congenic mouse model (hDPP4 KI). Following a single-dose intranasal immunization, PIV5-MERS-S induced neutralizing antibody and robust T cell responses in hDPP4 KI mice. A single intranasal administration of 10(4) PFU PIV5-MERS-S provided complete protection against a lethal challenge with mouse-adapted MERS-CoV (MERS(MA)6.1.2) and improved virus clearance in the lung. In comparison, single-dose intramuscular immunization with 10(6) PFU UV-inactivated MERS(MA)6.1.2 mixed with Imject alum provided protection to only 25% of immunized mice. Intriguingly, an influx of eosinophils was observed only in the lungs of mice immunized with inactivated MERS-CoV, suggestive of a hypersensitivity-type response. Overall, our study indicated that PIV5-MERS-S is a promising effective vaccine candidate against MERS-CoV infection.

negative: Potential Therapeutic Targeting of Coronavirus Spike Glycoprotein Priming Processing of certain viral proteins and bacterial toxins by host serine proteases is a frequent and critical step in virulence. The coronavirus spike glycoprotein contains three (S1, S2, and S2') cleavage sites that are processed by human host proteases. The exact nature of these cleavage sites, and their respective processing proteases, can determine whether the virus can cross species and the level of pathogenicity. Recent comparisons of the genomes of the highly pathogenic SARS-CoV2 and MERS-CoV, with less pathogenic strains (e.g., Bat-RaTG13, the bat homologue of SARS-CoV2) identified possible mutations in the receptor binding domain and in the S1 and S2' cleavage sites of their spike glycoprotein. However, there remains some confusion on the relative roles of the possible serine proteases involved for priming. Using anthrax toxin as a model system, we show that in vivo inhibition of priming by pan-active serine protease inhibitors can be effective at suppressing toxicity. Hence, our studies should encourage further efforts in developing either pan-serine protease inhibitors or inhibitor cocktails to target SARS-CoV2 and potentially ward off future pandemics that could develop because of additional mutations in the S-protein priming sequence in coronaviruses.

negative: Efficacy and safety of Chou-Ling-Dan granules in the treatment of seasonal influenza via combining Western and traditional Chinese medicine: protocol for a multicentre, randomised controlled clinical trial INTRODUCTION: Chou-Ling-Dan (CLD) (Laggerapterodonta) granules are an ethnic herbal medicine from Yunnan province of China. CLD granules have been used for the treatment of inflammatory conditions and feverish diseases in China, including seasonal influenza, but few evidence-based medicine (EBM) clinical studies have been conducted to assess its efficacy and safety in the treatment of influenza. Here, we performed an EBM clinical trial combining Western Chinese medicine and traditional Chinese medicine (TCM) evaluation systems to evaluate the efficacy and safety of CLD granules in the treatment of seasonal influenza. METHODS AND ANALYSIS: The study is designed as a multicentre, randomised, double-blinded, double-simulation, oseltamivir-controlled and placebo-controlled, parallel-design clinical trial. Eligible subjects (n=318) will be allocated after satisfying the criteria (Western medicine). Subjects will be randomised to receive CLD granules, oseltamivir, or a placebo for 5 days of treatment and with follow-up after treatment to record symptoms and signs and to collect pharyngeal/throat swabs and serum samples for detecting the virus and antibodies. At the same time, the syndrome differentiation criteria of TCM, such as tongue body, furred tongue and type of pulse, will be recorded as determined by doctors of both Western and Chinese medicine. Participants will be instructed to comply with the protocol and to keep a daily record of symptoms. The primary and secondary outcomes and safety indicators will be used to evaluate the efficacy and safety of CLD granules in the treatment of seasonal influenza based on both Western Chinese medicine and TCM evaluation systems. ETHICS AND DISSEMINATION: The CLD granules clinical trial will be conducted in accordance with the Declaration of Helsinki and Good Clinical Practice and has been approved by the Ethics Committee of the First Affiliated Hospital of Guangzhou Medical University. All participants must provide written informed consent. The results obtained will be disseminated at international medical conferences and in peer-reviewed publications. TRIAL REGISTRATION NUMBER: NCT02662426; Pre-results.

negative: COVID-19, A Clinical Syndrome Manifesting as Hypersensitivity Pneumonitis

negative: Porcine Innate and Adaptative Immune Responses to Influenza and Coronavirus Infections abstract: Both innate and adaptative immune responses contribute to the control of infectious diseases, including by limiting the spreading of zoonotic diseases from animal reservoirs to humans. Pigs represent an important animal reservoir for influenza virus infection of human populations and are also naturally infected by coronaviruses, an important group of viruses, which includes the recently emerged severe acute respiratory syndrome (SARS) virus. Studies on both innate and adaptative immune responses of pigs to influenza virus and coronaviruses contribute, therefore, to a better control of these infections in their natural hosts and will be briefly reviewed in this article. Pro‐inflammatory cytokines, including type I interferon (IFN), tumor necrosis factor‐α (TNF‐α), and interleukin‐6 (IL‐6), were found in lung secretions of influenza virus infected pigs, and correlated with the intensity of clinical signs, whereas prior vaccination against influenza strongly reduced the production of infectious virus and cytokines in the lungs upon challenge, which was associated with clinical protection. An early type I IFN production was also found in coronavirus infected pigs, including at mucosal sites. IFN induction by coronavirus is shown to involve interaction between a viral glycoprotein and a leukocyte subset, likely equivalent to plasmacytoid dendritic cells, present in the mucosae and associated lymphoid tissues. Given the IFN mediated antiviral and immunomodulatory effects, the use of IFN or IFN inducers may prove an efficient strategy for a better control of influenza virus and coronavirus infections in pigs. Because influenza and coronaviruses target mucosal surfaces, adaptative immune responses have to be characterized at mucosal sites. Thus, nasal and pulmonary antibody responses were analyzed in influenza virus infected or vaccinated pigs showing short‐lived, but potentially protective local IgA and IgG antibody (Ab) responses. Interestingly, primary influenza virus infection induced long‐lived increase of lung CD8(+) T cells and local lymphoproliferative responses. Pigs infected by a respiratory coronavirus (PRCV) showed virus‐specific IgG Ab‐secreting cells in the bronchial lymph nodes, whereas the transmissible gastroenteritis coronavirus (TGEV) induced more IgA Ab‐secreting cells in gut tissues, which illustrates the importance of the route of antigen administration for inducing local immune effector mechanisms. Porcine viral infections provide, therefore, valuable models for evaluating the immune parameters that are important for controlling transmission of important viral zoonotic infections.

negative: The Optimal Age of Vaccination Against Dengue with an Age-Dependent Biting Rate with Application to Brazil In this paper we introduce a single serotype transmission model, including an age-dependent mosquito biting rate, to find the optimal vaccination age against dengue in Brazil with Dengvaxia. The optimal vaccination age and minimal lifetime expected risk of hospitalisation are found by adapting a method due to Hethcote (Math Biosci 89:29–52). Any number and combination of the four dengue serotypes DENv1–4 is considered. Successful vaccination against a serotype corresponds to a silent infection. The effects of antibody-dependent enhancement (ADE) and permanent cross-immunity after two heterologous infections are studied. ADE is assumed to imply risk-free primary infections, while permanent cross-immunity implies risk-free tertiary and quaternary infections. Data from trials of Dengvaxia indicate vaccine efficacy to be age and serostatus dependent and vaccination of seronegative individuals to induce an increased risk of hospitalisation. Some of the scenarios are therefore reconsidered taking these findings into account. The optimal vaccination age is compared to that achievable under the current age restriction of the vaccine. If vaccination is not considered to induce risk, optimal vaccination ages are very low. The assumption of ADE generally leads to a higher optimal vaccination age in this case. For a single serotype vaccination is not recommended in the case of ADE. Permanent cross-immunity results in a slightly lower optimal vaccination age. If vaccination induces a risk, the optimal vaccination ages are much higher, particularly for permanent cross-immunity. ADE has no effect on the optimal vaccination age when permanent cross-immunity is considered; otherwise, it leads to a slight increase in optimal vaccination age. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s11538-019-00690-1) contains supplementary material, which is available to authorized users.

negative: All eyes on Coronavirus—What do we need to know as ophthalmologists

negative: Enhanced Humoral Response to Influenza Vaccine in Aged Mice with A Novel Adjuvant, rOv-ASP-1 Immunization is the best way to prevent seasonal epidemics and pandemics of influenza. There are two kinds of influenza vaccines available in the United States: an inactivated vaccine (TIV) and an attenuated vaccine; however, only TIV is approved for immunization of the elderly population. While the aged population has the highest rate of influenza vaccination, the protective efficacy is low as evidenced by elderly individuals having the highest mortality associated with influenza. Recently, we reported that an adjuvant derived from the helminth parasite Onchocerca volvulus, named O. volvulus activation-associated secreted protein-1 (Ov-ASP-1), can significantly enhance the protective efficacy of an inactivated vaccine (TIV) in young adult mice. In the current study, we examined whether this recombinant Ov-ASP-1 (rOv-ASP-1) can enhance the efficacy of TIV in aged mice as well. While primary immunization with TIV alone produced only a low level of influenza-specific antibodies (total IgG, IgG1, and IgG2c) in aged mice, the antibody levels were significantly increased after immunization with TIV+rOv-ASP-1. More importantly, the level of the total IgG in aged mice administered TIV+rOv-ASP-1 was comparable to that of young adult mice immunized with TIV alone. Co-administration of rOv-ASP-1 induced a low level of crossreactive antibody and enhanced the protective efficacy of TIV in aged mice, reflected by significantly increased survival after challenge with a heterologous influenza virus. rOv-ASP-1 was also superior to the conventional adjuvant alum in inducing specific IgG after TIV immunization in aged mice, and in conferring protection after challenge. These results demonstrate that rOv-ASP-1 may serve as a potential adjuvant for influenza vaccine to improve the efficacy of protection in the elderly.

negative: 2019-novel Coronavirus severe adult respiratory distress syndrome in two cases in Italy: An uncommon radiological presentation Abstract Introduction Several recent case reports have described common early chest imaging findings of lung pathology caused by 2019 novel Coronavirus (SARS-COV2) which appear to be similar to those seen previously in SARS-CoV and MERS-CoV infected patients. Objective We present some remarkable imaging findings of the first two patients identified in Italy with COVID-19 infection travelling from Wuhan, China. The follow-up with chest X-Rays and CT scans was also included, showing a progressive adult respiratory distress syndrome (ARDS). Results Moderate to severe progression of the lung infiltrates, with increasing percentage of high-density infiltrates sustained by a bilateral and multi-segmental extension of lung opacities, were seen. During the follow-up, apart from pleural effusions, a tubular and enlarged appearance of pulmonary vessels with a sudden caliber reduction was seen, mainly found in the dichotomic tracts, where the center of a new insurgent pulmonary lesion was seen. It could be an early alert radiological sign to predict initial lung deterioration. Another uncommon element was the presence of mediastinal lymphadenopathy with short-axis oval nodes. Conclusions Although only two patients have been studied, these findings are consistent with the radiological pattern described in literature. Finally, the pulmonary vessels enlargement in areas where new lung infiltrates develop in the follow-up CT scan, could describe an early predictor radiological sign of lung impairment.

negative: Control Strategies to Curtail Transmission of COVID-19 Recently, the World Health Organization has declared the outbreak of a severe acute respiratory syndrome coronavirius as a pandemic, and declared it as Public Health Emergency of International Concern. More than 6,83,536 positive cases and 32,139 deaths caused by coronavirus 2019 affecting 199 countries and territories. This pandemic can transform into an extremely destructive form if we still do not take it seriously. In this present study, we propose a generalized SEIR model of COVID-2019 to study the behavior of its transmission under different control strategies.

negative: Therapeutic Management of COVID-19 Patients: A systematic review Background: SARS-CoV-2 is the cause of the COVID-19 that has been declared a global pandemic by the WHO in 2020. The COVID-19 treatment guidelines vary in each country, and yet there is no approved therapeutic for COVID-19. Aims of the study: this review aimed to report any evidence of therapeutics used for the management of COVID-19 patients in clinical practice since the emergence of the virus. Methods: A systematic review protocol was developed based on PRISMA Statement. Articles for review were selected from electronic databases (Embase, Medline and Google Scholar). Readily accessible peer-reviewed full articles in English published from December 1 st , 2019 to March 26 th , 2020 were included. The search terms included combinations of: COVID, SARS-COV-2, glucocorticoids, convalescent plasma, antiviral, antibacterial. There were no restrictions on the type of study design eligible for inclusion. Results: As of March 26, 2020, of the initial manuscripts identified (n=449) articles. Forty-one studies were included, of which clinical trials (n=3), (case reports n=7), case series (n=10), retrospective (n=11) and prospective (n=10) observational studies. Thirty-six studies were conducted in China (88%). The most common mentioned and reported medicine in this systematic review was corticosteroids (n=25), followed by Lopinavir (n=21) and oseltamivir (n=16). Conclusions: This is the first systematic review up to date related to the therapeutics used in COVID-19 patients. Only forty-one research articles on COVID-19 and therapeutics were found eligible to be included, most conducted in China, corticosteroid therapy was found to be the most used medicine in these studies.

negative: Transmissible Turkey Enteritis Virus This chapter provides an overview of the classification, description, hosts, key developments, diagnostic techniques, and diagnostic reagents for the transmissible turkey enteritis virus. It is a highly infectious agent causing depression, diarrhea, and anorexia in all ages of turkeys, but young stocks are more severely affected. The main host for the virus are turkeys. The virus had not occurred in Western Europe until very recently. Clinical entity of the virus was first described in 1951. Diagnostic techniques for the virus include fluorescent antibody, virus neutralization, and electron microscopy. A cell-mediated immunity in vitro technique has recently been found for the detection of the virus.

negative: Mucosal immunity: an overview and studies of enteric and respiratory coronavirus infections in a swine model of enteric disease Abstract Based on the tenet of a common mucosal immune system, antigenic stimulation at one mucosal site results in the distribution of antigen-specific IgA precursor cells to distant mucosal sites. However, recent studies suggest that functional compartmentalization and limited reciprocity may exist within some components of the common mucosal immune system. Although oral immunization is often very effective in inducing immunity to respiratory pathogens, the converse (respiratory immunization to prevent enteric diseases) may not be as effective. To address this question and to study interactions between the bronchus-associated (BALT) and gut-associated (GALT) lymphoid tissues related to protective immunity, we used as a model two antigenically related porcine coronaviruses which replicate primarily in the intestine (transmissible gastroenteritis virus, TGEV) or respiratory tract (porcine respiratory coronavirus, PRCV). The tissue distribution and magnitude of the antibody secreting cell (ASC) responses (measured by ELISPOT) and cell-mediated immune responses (measured by lymphoproliferative assays, LPA) coincided with the viral tissue tropisms. Immunization via GALT (gut infection with TGEV) elicited high numbers of IgA ASC and high LPA responses in GALT (gut lamina propria, LP or mesenteric lymph nodes, MLN), but lower responses in BALT (bronchial lymph nodes, BLN) and induced complete protection against enteric TGEV challenge. In contrast immunization via BALT (respiratory infection with PRCV) elicited systemic type responses (high numbers of IgG ASC in the BLN), but few ASC and low LPA responses in the gut LP or MLN and induced only partial protection against enteric TGEV challenge. Thus administration of vaccines intranasally may not be optimally effective for inducing intestinal immunity in contrast to the reported efficacy of oral vaccines for inducing respiratory immunity.

negative: Cardiovascular Considerations for Patients, Health Care Workers, and Health Systems During the Coronavirus Disease 2019 (COVID-19) Pandemic Abstract The coronavirus disease-2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 that has significant implications for the cardiovascular care of patients. First, those with COVID-19 and preexisting cardiovascular disease (CVD) have an increased risk of severe disease and death. Second, infection has been associated with multiple direct and indirect cardiovascular complications including acute myocardial injury, myocarditis, arrhythmias and venous thromboembolism. Third, therapies under investigation for COVID-19 may have cardiovascular side effects. Fourth, the response to COVID-19 can compromise the rapid triage of non-COVID-19 patients with cardiovascular conditions. Finally, the provision of cardiovascular care may place health care workers in a position of vulnerability as they become host or vectors of virus transmission. We hereby review the peer-reviewed and preprint literature pertaining to cardiovascular considerations related to COVID-19 and highlight gaps in knowledge that require further study pertinent to patients, health care workers, and health systems.

negative: Effects of temperature and humidity on the spread of COVID-19: A systematic review. Background: Faced with the global pandemic of COVID-19, declared by World Health Organization (WHO) on March 11th 2020, and the need to better understand the seasonal behavior of the virus, our team conducted this systematic review to describe current knowledge about the emergence and replicability of the virus and its correlation with different weather factors such as temperature and relative humidity. Methods: The review was registered with the PROSPERO database. The electronic databases PubMed, Scopus, Web of Science, Cochrane Library, LILACS, OpenGrey and Google Scholar were examined with the searches restricted to the years 2019 and 2020. Risk of bias assessment was performed using the Joanna Briggs Institute (JBI) Critical Appraisal Checklist tool. The GRADE tool was used to assess the quality of the evidence. Results: The initial screening identified 517 articles. After examination of the full texts, seventeen studies met the review's eligibility criteria. Great homogeneity was observed in the findings regarding the effect of temperature and humidity on the seasonal viability and transmissibility of COVID-19. Cold and dry conditions were potentiating factors on the spread of the virus. After quality assessment, four studies had a high risk of bias and thirteen studies were scored as moderate risk of bias. The certainty of evidence was graded as low for both outcomes evaluated. Conclusion: Considering the existing scientific evidence, warm and wet climates seem to reduce the spread of COVID-19. The certainty of the evidence generated was graded as low. However, these variables alone could not explain most of the variability in disease transmission.

negative: Middle East respiratory syndrome coronavirus: a comprehensive review The Middle East respiratory syndrome coronavirus was first identified in 2012 and has since then remained uncontrolled. Cases have been mostly reported in the Middle East, however travel-associated cases and outbreaks have also occurred. Nosocomial and zoonotic transmission of the virus appear to be the most important routes. The infection is severe and highly fatal thus necessitating rapid and efficacious interventions. Here, we performed a comprehensive review of published literature and summarized the epidemiology of the virus. In addition, we summarized the virological aspects of the infection and reviewed the animal models used as well as vaccination and antiviral tested against it.

negative: PERSONAL PROTECTIVE EQUIPMENT (PPE) USING IN ANTALYA 112 EMERGENCY AMBULANCE SERVICES DURING OUTBREAK A new type of Coronavirus (SARS CoV2) which was identified on January 7th, 2020; which caused disease named COVID 19 caused by this virus. The first confirmed COVID 19 (+) case in Turkey was detected on March 11th, 2020. The first COVID-19 case in Antalya was detected on March 14th, 2020 and transferred by an Antalya 112 emergency ambulance to hospital. The aim of this descriptive, retrospective and cross-sectional study which is conducted between the dates of March 14th, 2020 and May 31st, 2020, is to evaluate the level of Personal Protective Equipment (PPE) usage, the risk analysis results and follow up measures of Antalya 112 ambulance teams during COVID-19 outbreak. There were 5344 possible and 787 confirmed COVID-19 (+) positive ambulance cases between the dates of study conducted. The majority of these cases were male (62%) and over the age of 65 (47%). The majority of cases were result in transferred to healthcare facilities (75.48%). The total 2361 ambulance team workers were taken to risk analysis measurements and then followed-up procedures. The majority of ambulance team members were assessed with no risk available. The Level 4 PPE (N95/FPP, Goggle/face protection, Gloves, Apron/coverall) were used most commonly (84.50%). The HCWs who use Level-4 PPE for confirmed COVID-19 (+) cases, were assessed no risk exposed. The using mask on patient and the level of PPE usage showed negative correlation with risk level of HCWs. There are only 2 HCWs diagnosed with COVID 19 by CT scan. The follow up procedures of two HCWs has been finalized, and both of them cured, follow ups ended. The studies about easy use, hightech PPE with maximum protection, are recommended for further investigations. Keywords: COVID 19, Ambulance Services, Personal Protective Equipment

negative: Dilemma of organ donation in transplantation and the COVID-19 pandemic

negative: Viral nanoparticles and virus‐like particles: platforms for contemporary vaccine design Current vaccines that provide protection against infectious diseases have primarily relied on attenuated or inactivated pathogens. Virus‐like particles (VLPs), comprised of capsid proteins that can initiate an immune response but do not include the genetic material required for replication, promote immunogenicity and have been developed and approved as vaccines in some cases. In addition, many of these VLPs can be used as molecular platforms for genetic fusion or chemical attachment of heterologous antigenic epitopes. This approach has been shown to provide protective immunity against the foreign epitopes in many cases. A variety of VLPs and virus‐based nanoparticles are being developed for use as vaccines and epitope platforms. These particles have the potential to increase efficacy of current vaccines as well as treat diseases for which no effective vaccines are available. WIREs Nanomed Nanobiotechnol 2011 3 174–196 DOI: 10.1002/wnan.119 1.. Therapeutic Approaches and Drug Discovery > Nanomedicine for Infectious Disease.

negative: Elicitation of broadly protective immunity to influenza by multivalent hemagglutinin nanoparticle vaccines Influenza vaccines that confer broad and durable protection against diverse virus strains would have a major impact on global health. However, next-generation vaccine design efforts have been complicated by challenges including the genetic plasticity of the virus and the immunodominance of certain epitopes in its glycoprotein antigens. Here we show that computationally designed, two-component nanoparticle immunogens induce potently neutralizing and broadly protective antibody responses against a wide variety of influenza viruses. The nanoparticle immunogens display 20 hemagglutinin (HA) trimers in a highly immunogenic array, and their assembly in vitro enables precisely controlled co-display of multiple distinct HAs in defined ratios. Nanoparticle immunogens displaying the four HAs of licensed quadrivalent influenza vaccines (QIV) elicited hemagglutination inhibition and neutralizing antibody responses to vaccine-matched strains that were equivalent or superior to commercial QIV in mice, ferrets, and nonhuman primates. The nanoparticle immunogens—but not QIV—simultaneously induced broadly protective antibody responses to heterologous viruses, including H5N1 and H7N9, by targeting the subdominant yet conserved HA stem. Unlike previously reported influenza vaccine candidates, our nanoparticle immunogens can alter the intrinsic immunodominance hierarchy of HA to induce both potent receptor-blocking and broadly cross-reactive stem-directed antibody responses and are attractive candidates for a next-generation influenza vaccine that could replace current seasonal vaccines. One Sentence Summary Nanoparticle immunogens displaying four seasonal influenza hemagglutinins elicit neutralizing antibodies directed at both the immunodominant head and the conserved stem and confer broad protective immunity.

negative: Middle East respiratory syndrome coronavirus (MERS-Cov) screening of exposed healthcare workers in a tertiary care hospital in Saudi Arabia

negative: Enhancing immunity in viral infections, with special emphasis on COVID-19: A review Abstract Background and aims Balanced nutrition which can help in maintaining immunity is essential for prevention and management of viral infections. While data regarding nutrition in coronavirus infection (COVID-19) are not available, in this review, we aimed to evaluated evidence from previous clinical trials that evaluated nutrition-based interventions for viral diseases (with special emphasis on respiratory infections), and summaries our observations. Methods A systematic search strategy was employed using keywords to search the literature in 3 key medical databases: PubMed®, Web of Science® and SciVerse Scopus®. Studies were considered eligible if they were controlled trials in humans, measuring immunological parameters, on viral and respiratory infections. Clinical trials on vitamins, minerals, nutraceuticals and probiotics were included. Results total of 640 records were identified initially and 22 studies were included from other sources. After excluding duplicates and articles that did not meet the inclusion criteria, 43 studies were obtained (vitamins: 13; minerals: 8; nutraceuticals: 18 and probiotics: 4). Among vitamins, A and D showed a potential benefit, especially in deficient populations. Among trace elements, selenium and zinc have also shown favourable immune-modulatory effects in viral respiratory infections. Several nutraceuticals and probiotics may have some role in enhancing immune functions. Micronutrients may be beneficial in nutritionally depleted elderly population. Conclusions We summaries possible benefits of some vitamins, trace elements, nutraceuticals and and probiotics. Nutrition principles based on these data could be useful in possible prevention and management of COVID-19

negative: Suppression of NK cells and regulatory T lymphocytes in cats naturally infected with feline infectious peritonitis virus Abstract A strong cell-mediated immunity (CMI) is thought to be indispensable for protection against infection with feline infectious peritonitis virus (FIPV) in cats. In this study, the role of natural killer (NK) cells and regulatory T cells (Tregs), central players in the innate and adaptive CMI respectively, was examined during natural FIPV infection. When quantified, both NK cells and Tregs were drastically depleted from the peripheral blood, mesenteric lymph node (LN) and spleen in FIP cats. In contrast, mesentery and kidney from FIP cats did not show any difference when compared to healthy non-infected control animals. In addition, other regulatory lymphocytes (CD4+CD25−Foxp3+ and CD3+CD8+Foxp3+) were found to be depleted from blood and LN as well. Phenotypic analysis of blood-derived NK cells in FIP cats revealed an upregulation of activation markers (CD16 and CD25) and migration markers (CD11b and CD62L) while LN-derived NK cells showed upregulation of only CD16 and CD62L. LN-derived NK cells from FIPV-infected cats were also significantly less cytotoxic when compared with healthy cats. This study reveals for the first time that FIPV infection is associated with severe suppression of NK cells and Tregs, which is reflected by cell depletion and lowered cell functionality (only NK cells). This will un-doubtfully lead to a reduced capacity of the innate immune system (NK cells) to battle FIPV infection and a decreased capacity (Tregs) to suppress the immunopathology typical for FIP. However, these results will also open possibilities for new therapies targeting specifically NK cells and Tregs to enhance their numbers and/or functionality during FIPV infection.

negative: HATRIC: a study of Pelargonium sidoides root extract EPs®7630 (Kaloba®) for the treatment of acute cough due to lower respiratory tract infection in adults—study protocol for a double blind, placebo-controlled randomised feasibility trial BACKGROUND: Acute lower respiratory tract infection is a common acute infection managed in primary care. The current dominant management strategy in the UK is antibiotics, despite widespread publicity regarding antimicrobial resistance and evidence that the small benefits of antibiotics do not outweigh the harms. There is a need to address the rising problem of antibiotic resistance by providing credible alternative strategies, which reduce symptom burden. There is sufficient evidence to recommend the use of Pelargonium sidoides root extract in order to warrant undertaking an independent clinical trial. We propose a feasibility study to demonstrate our ability to recruit and retain patients and conduct a placebo-controlled trial of Pelargonium sidoides extract EPs®7630 in lower respiratory tract infection where pneumonia is not suspected. Both the tablet and liquid formulations will be included. METHODS: The HATRIC trial is a double-blind randomised placebo-controlled feasibility study aiming to determine the potential to conduct a fully powered trial of Pelargonium sidoides root extract as an alternative to the inappropriate use of antibiotics for acute bronchitis in UK primary care. Primary care sites will be equally randomised to one of two formulation groups (tablet or liquid preparation). Additionally, within each site, patients will be evenly randomised to active or placebo treatment. Antibiotic consumption will be monitored during the trial, but the use of a delayed prescription strategy is encouraged. The target sample size for this study is 160 patients overall or 40 per arm, recruited from approximately 20 primary care sites. The analysis will be descriptive focusing on estimation with no formal comparison of groups taking place. DISCUSSION: If this trial demonstrates the feasibility of recruitment and delivery, we will seek funding for a fully powered placebo-controlled trial of Pelargonium sidoides root extract for the treatment of lower respiratory tract infections in primary care. TRIAL REGISTRATION: HATRIC was registered on the ISRCTN registry (ISRCTN17672884) on 16 August 2018.

negative: Immunogenicity of Candidate MERS-CoV DNA Vaccines Based on the Spike Protein MERS-coronavirus is a novel zoonotic pathogen which spread rapidly to >25 countries since 2012. Its apparent endemicity and the wide spread of its reservoir host (dromedary camels) in the Arabian Peninsula highlight the ongoing public health threat of this virus. Therefore, development of effective prophylactic vaccine needs to be urgently explored given that there are no approved prophylactics or therapeutics for humans or animals to date. Different vaccine candidates have been investigated but serious safety concerns remain over protein or full-length spike (S) protein-based vaccines. Here, we investigated the immunogenicity of naked DNA vaccines expressing different fragments of MERS-CoV S protein in mice. We found that plasmids expressing full-length (pS) or S1-subunit (pS1) could induce significant levels of S1-specific antibodies (Abs) but with distinct IgG isotype patterns. Specifically, pS1 immunization elicited a balanced Th1/Th2 response and generally higher levels of all IgG isotypes compared to pS vaccination. Interestingly, only mice immunized with pS1 demonstrated significant S1-specific cellular immune response. Importantly, both constructs induced cross-neutralizing Abs against multiple strains of human and camel origins. These results indicate that vaccines expressing S1-subunit of the MERS-CoV S protein could represent a potential vaccine candidate without the possible safety concerns associated with full-length protein-based vaccines.

negative: CD8(+) T cells in HIV control, cure and prevention HIV infection can be effectively treated by lifelong administration of combination antiretroviral therapy, but an effective vaccine will likely be required to end the HIV epidemic. Although the majority of current vaccine strategies focus on the induction of neutralizing antibodies, there is substantial evidence that cellular immunity mediated by CD8(+) T cells can sustain long-term disease-free and transmission-free HIV control and may be harnessed to induce both therapeutic and preventive antiviral effects. In this Review, we discuss the increasing evidence derived from individuals who spontaneously control infection without antiretroviral therapy as well as preclinical immunization studies that provide a clear rationale for renewed efforts to develop a CD8(+) T cell-based HIV vaccine in conjunction with B cell vaccine efforts. Further, we outline the remaining challenges in translating these findings into viable HIV prevention, treatment and cure strategies.

negative: A single-cell atlas of the peripheral immune response to severe COVID-19 There is an urgent need to better understand the pathophysiology of Coronavirus disease 2019 (COVID-19), the global pandemic caused by SARS-CoV-2. Here, we apply single-cell RNA sequencing (scRNA-seq) to peripheral blood mononuclear cells (PBMCs) of 7 patients hospitalized with confirmed COVID-19 and 6 healthy controls. We identify substantial reconfiguration of peripheral immune cell phenotype in COVID-19, including a heterogeneous interferon-stimulated gene (ISG) signature, HLA class II downregulation, and a novel B cell-derived granulocyte population appearing in patients with acute respiratory failure requiring mechanical ventilation. Importantly, peripheral monocytes and lymphocytes do not express substantial amounts of pro-inflammatory cytokines, suggesting that circulating leukocytes do not significantly contribute to the potential COVID-19 cytokine storm. Collectively, we provide the most thorough cell atlas to date of the peripheral immune response to severe COVID-19.

negative: Cardiovascular disease and COVID-19 Abstract Background and aims Many patients with coronavirus disease 2019 (COVID-19) have underlying cardiovascular (CV) disease or develop acute cardiac injury during the course of the illness. Adequate understanding of the interplay between COVID-19 and CV disease is required for optimum management of these patients. Methods A literature search was done using PubMed and Google search engines to prepare a narrative review on this topic. Results Respiratory illness is the dominant clinical manifestation of COVID-19; CV involvement occurs much less commonly. Acute cardiac injury, defined as significant elevation of cardiac troponins, is the most commonly reported cardiac abnormality in COVID-19. It occurs in approximately 8–12% of all patients. Direct myocardial injury due to viral involvement of cardiomyocytes and the effect of systemic inflammation appear to be the most common mechanisms responsible for cardiac injury. The information about other CV manifestations in COVID-19 is very limited at present. Nonetheless, it has been consistently shown that the presence of pre-existing CV disease and/or development of acute cardiac injury are associated with significantly worse outcome in these patients. Conclusions Most of the current reports on COVID-19 have only briefly described CV manifestations in these patients. Given the enormous burden posed by this illness and the significant adverse prognostic impact of cardiac involvement, further research is required to understand the incidence, mechanisms, clinical presentation and outcomes of various CV manifestations in COVID-19 patients.

negative: Prevention and Control Strategies for SARS-CoV-2 Infection The population of 168 countries all over the world is struggling with the outbreak of COVID-19. The outbreak is declared as pandemic and public health emergency of international concern declared by WHO. SARS-CoV-2 responsible for the present health emergency exhibited close resemblance with SARS-CoV. Both the viruses are zoonotic and belong to a large family of viruses Coronaviridae. The complete virus particle is made up of four major structural proteins, namely spikes (S), nucleocapsid (N), membrane (M), and envelope (E) encoded by virus genome. The S protein of virus shows similarity to S protein of SARS-CoV. COVID-19 spreads from person to person, and this makes it more vulnerable for causing infection. Several efforts are taken to find prevention strategies for COVID-19. Researchers across the globe are working to find effective vaccination for SARS-CoV-2. There is no vaccine or medication available till date for COVID-19. Preventive measures such as social distancing, awareness, maintenance of hygiene, isolation, and movement restrictions can help in control of COVID-19 spread. Proper sanitization and cleaned and sanitized public transport can be effective in inhibiting the spread of the virus. In the present situation of medical emergency, cooperation and support by following advices from the WHO and government only facilitate everyone to come over.

negative: Hot Topic Commentary on COVID-19 The recent pandemic outbreak of COVID-19 (severe acute respiratory syndrome coronavirus 2; SARS-CoV-2) worldwide caught the health care systems in every country around the world by storm and without a proper defense mechanism to cope and control such a pandemic. In this special Theme issue, we would like to discuss the latest treatment modalities available around the world in tackling this dreadful disease.

negative: Why is COVID-19 so mild in children? There is an urgent need to understand why the course of the coronavirus that started in late 2019 (COVID-19) is affecting different groups of individuals with varying severity during the ongoing global pandemic. Greater knowledge of the disease, which is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV2), will help us to prioritise our limited health resources. Because the virus is new, and no vaccine is yet available, everyone is naïve and susceptible to being infected with SARS-CoV2. The virus will continue to spread until an effective vaccine exists or sufficient members of our global population have been infected to establish herd immunity. At the moment, the best way to minimize loss of life and severe cases requiring intensive care is to try and shelter vulnerable groups of individuals and slow down the spread of the virus.

negative: Cyberbiosecurity Challenges of Pathogen Genome Databases Pathogen detection, identification, and tracking is shifting from non-molecular methods, DNA fingerprinting methods, and single gene methods to methods relying on whole genomes. Viral Ebola and influenza genome data are being used for real-time tracking, while food-borne bacterial pathogen outbreaks and hospital outbreaks are investigated using whole genomes in the UK, Canada, the USA and the other countries. Also, plant pathogen genomes are starting to be used to investigate plant disease epidemics such as the wheat blast outbreak in Bangladesh. While these genome-based approaches provide never-seen advantages over all previous approaches with regard to public health and biosecurity, they also come with new vulnerabilities and risks with regard to cybersecurity. The more we rely on genome databases, the more likely these databases will become targets for cyber-attacks to interfere with public health and biosecurity systems by compromising their integrity, taking them hostage, or manipulating the data they contain. Also, while there is the potential to collect pathogen genomic data from infected individuals or agricultural and food products during disease outbreaks to improve disease modeling and forecast, how to protect the privacy of individuals, growers, and retailers is another major cyberbiosecurity challenge. As data become linkable to other data sources, individuals and groups become identifiable and potential malicious activities targeting those identified become feasible. Here, we define a number of potential cybersecurity weaknesses in today's pathogen genome databases to raise awareness, and we provide potential solutions to strengthen cyberbiosecurity during the development of the next generation of pathogen genome databases.

negative: Communicable Diseases: Achievements and Challenges for Public Health The past two centuries have seen enormous achievements in control of infectious diseases, previously the leading cause of death, in large measure due to sanitation and food safety, vaccines, antibiotics and improved nutrition. This has led people to put their faith in the notion that medical science would succeed in overcoming the remaining obstacles. Vaccination has eradicated smallpox, nearly eradicated poliomyelitis and greatly reduced many other highly dangerous infections such as diphtheria, tetanus and measles. New diseases such as HIV and new forms of influenza have taken both professional and popular opinion by surprise and have renewed the challenges before the world public health community. Emergence of antibiotic-resistant strains of common organisms due to overuse of antibiotics and lack of vaccines for many dangerous microorganisms poses problems to humanity. This stresses the need for new vaccines, effective antibiotics and strengthened environmental control measures. New knowledge of the microbiological origins of cancers such as that of the cervix, stomach and liver have strengthened primary prevention and brought hope that new cures will be found for other chronic diseases of infectious origin. Tragically long delays in adopting “new” and cost effective vaccines cause hundreds of thousands of preventable deaths each year in developing and mid-level developed countries. Gains are being made in control of many tropical diseases, but malaria, tuberculosis and other infectious diseases remain enormous global problems. Research and acquisition of new knowledge, risk communication, application of currently available means and fair distribution will be great challenges to public health in the coming decades.

negative: Measures for diagnosing and treating infections by a novel coronavirus responsible for a pneumonia outbreak originating in Wuhan, China Abstract On 10 January 2020, a new coronavirus causing a pneumonia outbreak in Wuhan City in central China was denoted as 2019-nCoV by the World Health Organization (WHO). As of 24 January 2020, there were 887 confirmed cases of 2019-nCoV infection, including 26 deaths, reported in China and other countries. Therefore, combating this new virus and stopping the epidemic is a matter of urgency. Here, we focus on advances in research and development of fast diagnosis methods, as well as potential prophylactics and therapeutics to prevent or treat 2019-nCoV infection.

negative: A synthetic consensus anti-spike protein DNA vaccine induces protective immunity against Middle East respiratory syndrome coronavirus in nonhuman primates. First identified in 2012, Middle East respiratory syndrome (MERS) is caused by an emerging human coronavirus, which is distinct from the severe acute respiratory syndrome coronavirus (SARS-CoV), and represents a novel member of the lineage C betacoronoviruses. Since its identification, MERS coronavirus (MERS-CoV) has been linked to more than 1372 infections manifesting with severe morbidity and, often, mortality (about 495 deaths) in the Arabian Peninsula, Europe, and, most recently, the United States. Human-to-human transmission has been documented, with nosocomial transmission appearing to be an important route of infection. The recent increase in cases of MERS in the Middle East coupled with the lack of approved antiviral therapies or vaccines to treat or prevent this infection are causes for concern. We report on the development of a synthetic DNA vaccine against MERS-CoV. An optimized DNA vaccine encoding the MERS spike protein induced potent cellular immunity and antigen-specific neutralizing antibodies in mice, macaques, and camels. Vaccinated rhesus macaques seroconverted rapidly and exhibited high levels of virus-neutralizing activity. Upon MERS viral challenge, all of the monkeys in the control-vaccinated group developed characteristic disease, including pneumonia. Vaccinated macaques were protected and failed to demonstrate any clinical or radiographic signs of pneumonia. These studies demonstrate that a consensus MERS spike protein synthetic DNA vaccine can induce protective responses against viral challenge, indicating that this strategy may have value as a possible vaccine modality against this emerging pathogen.

negative: Infectious Diseases and Microbiological Threats “The time to close the book on infectious disease” is far from near. Infections seem to be here to stay and have increased in importance in spite of enormous success in the field of prophylactic efforts, hygiene, vaccinology, and treatment. A large number of new agents and infections have appeared during the last decades. Conditions earlier thought to have other etiologies are today known to be distinct and have been proven to be of infectious origin. Infections alone can constitute major incidents, or they can be part of or a consequence of an incident. Even in the relatively new incident category of terrorism, infections must be seriously considered. Climate change and other changes in nature today constitute major threats of increasing infectious incidents. The increasing problem with antimicrobial resistance is, at present, considered to be one of the strongest disease threats. Infectious incidents are unique in the sense that they usually have an insidious onset, have a time span before they are detected as present or even as serious. Once the infection has started to spread, the development and increase can be extremely quick, even logarithmic. The extent of infectious incidents can be larger than that of most other disasters, and is best exemplified through different pandemics. The most important weapon to control infectious outbreaks or epidemics is active surveillance, leading to different kind of actions.

negative: The immune vulnerability landscape of the 2019 Novel Coronavirus, SARS-CoV-2 The outbreak of the 2019 Novel Coronavirus (SARS-CoV-2) rapidly spread from Wuhan, China to more than 150 countries, areas or territories, causing staggering number of infections and deaths. A systematic profiling of the immune vulnerability landscape of SARS-CoV-2, which can bring critical insights into the immune clearance mechanism, peptide vaccine development, and antiviral antibody development, is lacking. In this study, we investigated the potential of the SARS-CoV-2 viral proteins to induce class I and II MHC presentation and to form linear antibody epitopes. We created an online database to broadly share the predictions as a resource for the research community. Using this resource, we showed that genetic variations in SARS- CoV-2, though still few for the moment, already follow the pattern of mutations in related coronaviruses, and could alter the immune vulnerability landscape of this virus. Importantly, we discovered evidence that SARS-CoV-2, along with related coronaviruses, used mutations to evade attack from the human immune system. Overall, we present an immunological resource for SARS-CoV-2 that could promote both therapeutic development and mechanistic research.

negative: Innate and adaptive immunity against Porcine Reproductive and Respiratory Syndrome Virus Abstract Many highly effective vaccines have been produced against viruses whose virulent infection elicits strong and durable protective immunity. In these cases, characterization of immune effector mechanisms and identification of protective epitopes/immunogens has been informative for the development of successful vaccine programs. Diseases in which the immune system does not rapidly clear the acute infection and/or convalescent immunity does not provide highly effective protection against secondary challenge pose a major hurdle for clinicians and scientists. Porcine reproductive and respiratory syndrome virus (PRRSV) falls primarily into this category, though not entirely. PRRSV causes a prolonged infection, though the host eventually clears the virus. Neutralizing antibodies can provide passive protection when present prior to challenge, though infection can be controlled in the absence of detectable neutralizing antibodies. In addition, primed pigs (through natural exposure or vaccination with a modified-live vaccine) show some protection against secondary challenge. While peripheral PRRSV-specific T cell responses have been examined, their direct contribution to antibody-mediated immunity and viral clearance have not been fully elucidated. The innate immune response following PRRSV infection, particularly the antiviral type I interferon response, is meager, but when provided exogenously, IFN-α enhances PRRSV immunity and viral control. Overall, the quality of immunity induced by natural PRRSV infection is not ideal for informing vaccine development programs. The epitopes necessary for protection may be identified through natural exposure or modified-live vaccines and subsequently applied to vaccine delivery platforms to accelerate induction of protective immunity following vaccination. Collectively, further work to identify protective B and T cell epitopes and mechanisms by which PRRSV eludes innate immunity will enhance our ability to develop more effective methods to control and eliminate PRRS disease.

negative: T cell responses to whole SARS coronavirus in humans. Effective vaccines should confer long-term protection against future outbreaks of severe acute respiratory syndrome (SARS) caused by a novel zoonotic coronavirus (SARS-CoV) with unknown animal reservoirs. We conducted a cohort study examining multiple parameters of immune responses to SARS-CoV infection, aiming to identify the immune correlates of protection. We used a matrix of overlapping peptides spanning whole SARS-CoV proteome to determine T cell responses from 128 SARS convalescent samples by ex vivo IFN-gamma ELISPOT assays. Approximately 50% of convalescent SARS patients were positive for T cell responses, and 90% possessed strongly neutralizing Abs. Fifty-five novel T cell epitopes were identified, with spike protein dominating total T cell responses. CD8(+) T cell responses were more frequent and of a greater magnitude than CD4(+) T cell responses (p < 0.001). Polychromatic cytometry analysis indicated that the virus-specific T cells from the severe group tended to be a central memory phenotype (CD27(+)/CD45RO(+)) with a significantly higher frequency of polyfunctional CD4(+) T cells producing IFN-gamma, TNF-alpha, and IL-2, and CD8(+) T cells producing IFN-gamma, TNF-alpha, and CD107a (degranulation), as compared with the mild-moderate group. Strong T cell responses correlated significantly (p < 0.05) with higher neutralizing Ab. The serum cytokine profile during acute infection indicated a significant elevation of innate immune responses. Increased Th2 cytokines were observed in patients with fatal infection. Our study provides a roadmap for the immunogenicity of SARS-CoV and types of immune responses that may be responsible for the virus clearance, and should serve as a benchmark for SARS-CoV vaccine design and evaluation.

negative: Estimating the ascertainment rate of SARS-CoV-2 infection in Wuhan, China: implications for management of the global outbreak We sought to estimate the ascertainment ratio of SARS-CoV-2 infection in Wuhan, China, using a modified Bayesian SEIR model with publicly reported case data. We estimated it at 0.465% (95%CI: 0.464-0.466%), implying that the outbreak in Wuhan was abated by depletion of susceptibles, rather than public health action alone. This suggests a high-transmissibility/low-severity profile for the current pandemic and raises doubt about whether suppression, rather than mitigation, is a feasible goal.

negative: Feline Coronavirus in Multicat Environments Feline infectious peritonitis (FIP), a fatal disease in cats worldwide, is caused by FCoV infection, which commonly occurs in multicat environments. The enteric FCoV, referred to as feline enteric virus (FECV), is considered a mostly benign biotype infecting the gut, whereas the FIP virus biotype is considered the highly pathogenic etiologic agent for FIP. Current laboratory tests are unable to distinguish between virus biotypes of FCoV. FECV is highly contagious and easily spreads in multicat environments; therefore, the challenges to animal shelters are tremendous. This review summarizes interdisciplinary current knowledge in regard to virology, immunology, pathology, diagnostics, and treatment options in the context of multicat environments.

negative: Development of CRISPR as a prophylactic strategy to combat novel coronavirus and influenza The outbreak of the coronavirus disease 2019 (COVID-19), caused by the Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2), has infected more than 100,000 people worldwide with over 3,000 deaths since December 2019. There is no cure for COVID-19 and the vaccine development is estimated to require 12-18 months. Here we demonstrate a CRISPR-Cas13-based strategy, PAC-MAN (Prophylactic Antiviral CRISPR in huMAN cells), for viral inhibition that can effectively degrade SARS-CoV-2 sequences and live influenza A virus (IAV) genome in human lung epithelial cells. We designed and screened a group of CRISPR RNAs (crRNAs) targeting conserved viral regions and identified functional crRNAs for cleaving SARS-CoV-2. The approach is effective in reducing respiratory cell viral replication for H1N1 IAV. Our bioinformatic analysis showed a group of only six crRNAs can target more than 90% of all coronaviruses. The PAC-MAN approach is potentially a rapidly implementable pan-coronavirus strategy to deal with emerging pandemic strains.

negative: Cardiovascular Complications in Patients with COVID-19: Consequences of Viral Toxicities and Host Immune Response PURPOSE OF REVIEW: Coronavirus disease of 2019 (COVID-19) is a cause of significant morbidity and mortality worldwide. While cardiac injury has been demonstrated in critically ill COVID-19 patients, the mechanism of injury remains unclear. Here, we review our current knowledge of the biology of SARS-CoV-2 and the potential mechanisms of myocardial injury due to viral toxicities and host immune responses. RECENT FINDINGS: A number of studies have reported an epidemiological association between history of cardiac disease and worsened outcome during COVID infection. Development of new onset myocardial injury during COVID-19 also increases mortality. While limited data exist, potential mechanisms of cardiac injury include direct viral entry through the angiotensin-converting enzyme 2 (ACE2) receptor and toxicity in host cells, hypoxia-related myocyte injury, and immune-mediated cytokine release syndrome. Potential treatments for reducing viral infection and excessive immune responses are also discussed. SUMMARY: COVID patients with cardiac disease history or acquire new cardiac injury are at an increased risk for in-hospital morbidity and mortality. More studies are needed to address the mechanism of cardiotoxicity and the treatments that can minimize permanent damage to the cardiovascular system.

negative: Hypothesized behavioral host manipulation by SARS-CoV2 / COVID-19 infection Abstract Although not widely studied, behavioral host manipulation by various pathogens has been documented. Host manipulation is the process by which a pathogen evolves adaptations to manipulate the behavior of the host to maximize reproduction (Ro) of the pathogen. The most notable example is rabies. When a host is infected with the rabies virus it gets into the host’s central nervous system and triggers hyper aggression. The virus is also present in the rabid animal’s saliva so being bitten transmits the infection to a new host and the old host is left to eventually die if untreated. Toxoplasmosis is another example. When mice are infected they demonstrate a fearlessness toward cats, thus increasing their chances of being eaten. Toxoplasmosis needs the digestive tract of the feline to survive. Recent studies have shown that exposure to toxoplasmosis in humans (e.g., through cat feces) has also been associated with behavioral changes that are predicted to enhance the spread of the pathogen. Even the common influenza virus has been shown to selectively increase in-person sociality during the 48-hour incubation period, thus producing an obvious vector for transmission. Here we hypothesize that the novel coronavirus, SARS-CoV2, which produces the COVID-19 disease may produce similar host manipulations that maximize its transmission between humans.

negative: Diseases of the Alimentary Tract: Nonruminant

negative: Comparative study of patients with and without SARS WHO fulfilled the WHO SARS case definition Abstract To differentiate severe acute respiratory syndrome (SARS) from non-SARS illness, we retrospectively compared 53 patients with probable SARS and 31 patients with non-SARS who were admitted to Mackay Memorial Hospital from April 27 to June 16, 2003. Fever (> 38°C) was the earliest symptom (50/53 SARS vs. 5/31 non-SARS, p < 0.0001), preceding cough by a mean of 4.5 days. The initial chest X-ray study was normal in 22/53 SARS cases versus 5/31 non-SARS cases. SARS patients with an initially normal chest X-ray study developed infiltrates at a mean of 5 ± 3.44 days after onset of fever (21/22 SARS vs. 0/5 non-SARS). Rapid radiographic progression of unifocal involvement to multifocal infiltrates was seen in 22 of 24 SARS vs. 0 of 26 non-SARS patients (p < 0.0001). Pleural effusion was not present in any SARS patients but was seen in 6 of 26 non-SARS cases (p < 0.0001). Initial lymphopenia, thrombocytopenia, and elevated lactate dehydrogenase were all more common in SARS than non-SARS (p < 0.0001). They may help differentiate SARS from non-SARS if a reliable and rapid diagnostic test is not available.

negative: Crystal structure of Nsp15 endoribonuclease NendoU from SARS-CoV-2 Severe Acute Respiratory Syndrome Coronavirus 2 is rapidly spreading around the world. There is no existing vaccine or proven drug to prevent infections and stop virus proliferation. Although this virus is similar to human and animal SARS- and MERS-CoVs the detailed information about SARS-CoV-2 proteins structures and functions is urgently needed to rapidly develop effective vaccines, antibodies and antivirals. We applied high-throughput protein production and structure determination pipeline at the Center for Structural Genomics of Infectious Diseases to produce SARS-CoV-2 proteins and structures. Here we report the high-resolution crystal structure of endoribonuclease Nsp15/NendoU from SARS-CoV-2 – a virus causing current world-wide epidemics. We compare this structure with previously reported models of Nsp15 from SARS and MERS coronaviruses.

negative: Epidemiological and Clinical Characteristics of Children with Coronavirus Disease 2019 Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a newly identified pathogen which mainly spreads by droplets. Most published studies focused on adult patients with coronavirus disease 2019 (COVID-19), but data concerning pediatric patients is limited. This study aimed to determine epidemiological characteristics and clinical features of pediatric patients with COVID-19. Methods: We reviewed and analyzed data on pediatric patients with laboratory-confirmed COVID-19, including basic information, epidemiological history, clinical manifestations, laboratory and radiologic findings, treatment, outcome and follow-up results. Results: From January 20th to February 27th of 2020, a total of 74 pediatric patients with COVID-19 were included in this study. Of the 68 cases whose epidemiological data were complete, 65 (65/68, 95.59%) cases were household contacts of adults whose symptoms developed earlier. Forty (59.46%) of the infected children were male, and the median age and body weight are 6 (0.10-15.08) years and 24 (4.20-87.00) kg, respectively. Except for one critically ill case, 20 (27.03%) patients did not show any symptoms of infection, 24 (32.43%) patients had acute upper respiratory tract infection and 29 (39.19%) patients were diagnosed with mild pneumonia. Cough (24/74, 32.43%) and fever (20, 27.03%) were the predominant symptoms of 44 (59.46%) symptomatic patients at onset of the illness. Abnormalities in leukocyte count were found in 23 (31.08%) children and 10 (13.51%) children presented with abnormal lymphocyte count. Of the 34 (45.95%) patients who had nucleic acid testing results for common respiratory pathogens, 19 (19 / 34, 51.35%) showed co-infection with other pathogens other than SARS-CoV-2.Ten (13.51%) children had RT-PCR analysis of SARS-CoV-2 for fecal specimens and 8 of them showed prolonged existence of SARS-CoV-2 RNA 11 (5-23) days after nasopharynx swabs turning negative. Abnormalities in chest imaging were observed in 37 (50.00%) patients and 28 (37.84%) of them only presented with nontypical changes.All children had good prognosis with a median hospitalization duration of 11 days and follow-up period of 16.5 days. During the follow-up period, all the patients remained in quarantine at designated site and home for two 14-day obervation periods and showed no clinical manifestation,but 3 of the 8 cases with prolonged fecal shedding of SARS-CoV-2 still showed positive result of feces test.

negative: Single-Dose, Intranasal Immunization with Recombinant Parainfluenza Virus 5 Expressing Middle East Respiratory Syndrome Coronavirus (MERS-CoV) Spike Protein Protects Mice from Fatal MERS-CoV Infection Middle East respiratory syndrome coronavirus (MERS-CoV) can cause severe and fatal acute respiratory disease in humans and remains endemic in the Middle East since first being identified in 2012. There are currently no approved vaccines or therapies available for MERS-CoV. In this study, we evaluated parainfluenza virus 5 (PIV5)-based vaccine expressing the MERS-CoV envelope spike protein (PIV5/MERS-S) in a human DPP4 knockin C57BL/6 congenic mouse model (hDPP4 KI). Following a single-dose intranasal immunization, PIV5-MERS-S induced neutralizing antibody and robust T cell responses in hDPP4 KI mice. A single intranasal administration of 104 PFU PIV5-MERS-S provided complete protection against a lethal challenge with mouse-adapted MERS-CoV (MERSMA6.1.2) and improved virus clearance in the lung. In comparison, single-dose intramuscular immunization with 106 PFU UV-inactivated MERSMA6.1.2 mixed with Imject alum provided protection to only 25% of immunized mice. Intriguingly, an influx of eosinophils was observed only in the lungs of mice immunized with inactivated MERS-CoV, suggestive of a hypersensitivity-type response. Overall, our study indicated that PIV5-MERS-S is a promising effective vaccine candidate against MERS-CoV infection.IMPORTANCE MERS-CoV causes lethal infection in humans, and there is no vaccine. Our work demonstrates that PIV5 is a promising vector for developing a MERS vaccine. Furthermore, success of PIV5-based MERS vaccine can be employed to develop a vaccine for emerging CoVs such as SARS-CoV-2, which causes COVID-19.

negative: ACE2 expression by colonic epithelial cells is associated with viral infection, immunity and energy metabolism Respiratory disease caused by the 2019 novel coronavirus (2019-nCoV) pneumonia first emerged in Wuhan, Hubei Province, China, in December 2019 and spread rapidly to other provinces and other countries. Angiotensin-converting enzyme 2 (ACE2) is the receptor for SARS-CoV and has been suggested to be also the receptor for 2019-nCoV. Paradoxically, ACE2 expression in the lung protects mice from SARS-CoV spike protein induced lung injury by attenuating the renin-angiotensin system. In the intestine, ACE2 also suppresses intestinal inflammation by maintaining amino acid homeostasis, antimicrobial peptide expression and ecology of the gut microbiome. Upon analysis of single cell-RNA sequencing data from control subjects and those with colitis or inflammatory bowel disease (IBD), we found that ACE2 expression in the colonocytes was positively associated with genes regulating viral infection, innate and cellular immunity, but was negatively associated with viral transcription, protein translation, humoral immunity, phagocytosis and complement activation. In summary, we suggest that ACE2 may play dual roles in mediating the susceptibility and immunity of 2019-nCoV infection.

negative: From SARS-CoV to SARS-CoV-2: safety and broad-spectrum are important for coronavirus vaccine development The global pandemic of COVID-19 caused by SARS-CoV-2 (also known as 2019-nCoV and HCoV-19) has posed serious threats to public health and economic stability worldwide, thus calling for development of vaccines against SARS-CoV-2 and other emerging and reemerging coronaviruses. Since SARS-CoV-2 and SARS-CoV have high similarity of their genomic sequences and share the same cellular receptor (ACE2), it is essential to learn the lessons and experiences from the development of SARS-CoV vaccines for the development of SARS-CoV-2 vaccines. In this review, we summarized the current knowledge on the advantages and disadvantages of the SARS-CoV vaccine candidates and prospected the strategies for the development of safe, effective and broad-spectrum coronavirus vaccines for prevention of infection by currently circulating SARS-CoV-2 and other emerging and reemerging coronaviruses that may cause future epidemics or pandemics.

negative: On the probability of strain invasion in endemic settings: Accounting for individual heterogeneity and control in multi-strain dynamics Abstract Pathogen evolution is an imminent threat to global health that has warranted, and duly received, considerable attention within the medical, microbiological and modelling communities. Outbreaks of new pathogens are often ignited by the emergence and transmission of mutant variants descended from wild-type strains circulating in the community. In this work we investigate the stochastic dynamics of the emergence of a novel disease strain, introduced into a population in which it must compete with an existing endemic strain. In analogy with past work on single-strain epidemic outbreaks, we apply a branching process approximation to calculate the probability that the new strain becomes established. As expected, a critical determinant of the survival prospects of any invading strain is the magnitude of its reproduction number relative to that of the background endemic strain. Whilst in most circumstances this ratio must exceed unity in order for invasion to be viable, we show that differential control scenarios can lead to less-fit novel strains invading populations hosting a fitter endemic one. This analysis and the accompanying findings will inform our understanding of the mechanisms that have led to past instances of successful strain invasion, and provide valuable lessons for thwarting future drug-resistant strain incursions.

negative: SARS-CoV2 infection and primary school closure

negative: Impact of immune enhancement on Covid-19 polyclonal hyperimmune globulin therapy and vaccine development Abstract The pandemic spread of a novel coronavirus – SARS coronavirus-2 (SARS-CoV-2) as a cause of acute respiratory illness, named Covid-19, is placing the healthcare systems of many countries under unprecedented stress. Global economies are also spiraling towards a recession in fear of this new life-threatening disease. Vaccines that prevent SARS-CoV-2 infection and therapeutics that reduces the risk of severe Covid-19 are thus urgently needed. A rapid method to derive antiviral treatment for Covid-19 is the use of convalescent plasma derived hyperimmune globulin. However, both hyperimmune globulin and vaccine development face a common hurdle – the risk of antibody-mediated disease enhancement. The goal of this review is to examine the body of evidence supporting the hypothesis of immune enhancement that could be pertinent to Covid-19. We also discuss how this risk could be mitigated so that both hyperimmune globulin and vaccines could be rapidly translated to overcome the current global health crisis.

negative: Potential Treatments for COVID-19; a Narrative Literature Review SARS-CoV-2 is a newly emerging human infectious coronavirus that causes COVID-19, which has been recognized as a pandemic by the World Health Organization (WHO) on March 11(th). There is still no vaccine or definitive treatment for this virus because its pathogenesis and proliferation pathways are still unknown. Therefore, in this article, new potential COVID-19 therapies are briefly reviewed.

negative: Tissue-resident CD8+ T cells drive age-associated chronic lung sequelae following viral pneumonia Lower respiratory viral infections, such as influenza virus and severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infections, often cause severe viral pneumonia in aged individuals. Here, we report that influenza viral pneumonia leads to chronic non-resolving lung pathology and exaggerated accumulation of CD8+ tissue-resident memory T cells (TRM) in the respiratory tract of aged hosts. TRM accumulation relies on elevated TGF-β present in aged tissues. Further, we show that TRM isolated from aged lungs lack a subpopulation characterized by expression of molecules involved in TCR signaling and effector function. Consequently, TRM cells from aged lungs were insufficient to provide heterologous protective immunity. Strikingly, the depletion of CD8+ TRM cells dampens persistent chronic lung inflammation and ameliorates tissue fibrosis in aged, but not young, animals. Collectively, our data demonstrate that age-associated TRM cell malfunction supports chronic lung inflammatory and fibrotic sequelae following viral pneumonia in aged hosts.

negative: COVID-19, Modern Pandemic: A Systematic Review From Front-Line Health Care Providers’ Perspective Coronavirus disease 2019 (COVID-19) caused infection in 168,000 cases worldwide in about 148 countries and killed more than 6,610 people around the world as of March 16, 2020, as per the World Health Organization (WHO). Compared to severe acute respiratory syndrome and Middle East respiratory syndrome, there is the rapid transmission, long incubation period, and disease containment is becoming extremely difficult. The main aim of this systematic review is to provide a comprehensive clinical summary of all the available data from high-quality research articles relevant to the epidemiology, demographics, trends in hospitalization and outcomes, clinical signs and symptoms, diagnostic methods and treatment methods of COVID-19, thus increasing awareness in health care providers. We also discussed various preventive measures to combat COVID-19 effectively. A systematic and protocol-driven approach is needed to contain this disease, which was declared as a global pandemic on March 11, 2020, by the WHO.

negative: SARS vaccines: where are we? In this review, the current state of vaccine development against human severe acute respiratory syndrome (SARS) coronavirus, focusing on recently published data is assessed. We discuss which strategies have been assessed immunologically and which have been evaluated in SARS coronavirus challenge models. We discuss inactivated vaccines, virally and bacterially vectored vaccines, recombinant protein and DNA vaccines, as well as the use of attenuated vaccines. Data regarding the correlates of protection, animal models and the available evidence regarding potential vaccine enhancement of SARS disease are discussed. While there is much evidence that various vaccine strategies against SARS are safe and immunogenic, vaccinated animals still display significant disease upon challenge. Current data suggest that intranasal vaccination may be crucial and that new or combination strategies may be required for good protective efficacy against SARS in humans.

negative: A Mouse Model for Betacoronavirus Subgroup 2c Using a Bat Coronavirus Strain HKU5 Variant Cross-species transmission of zoonotic coronaviruses (CoVs) can result in pandemic disease outbreaks. Middle East respiratory syndrome CoV (MERS-CoV), identified in 2012, has caused 182 cases to date, with ~43% mortality, and no small animal model has been reported. MERS-CoV and Pipistrellus bat coronavirus (BtCoV) strain HKU5 of Betacoronavirus (β-CoV) subgroup 2c share >65% identity at the amino acid level in several regions, including nonstructural protein 5 (nsp5) and the nucleocapsid (N) protein, which are significant drug and vaccine targets. BtCoV HKU5 has been described in silico but has not been shown to replicate in culture, thus hampering drug and vaccine studies against subgroup 2c β-CoVs. We report the synthetic reconstruction and testing of BtCoV HKU5 containing the severe acute respiratory syndrome (SARS)-CoV spike (S) glycoprotein ectodomain (BtCoV HKU5-SE). This virus replicates efficiently in cell culture and in young and aged mice, where the virus targets airway and alveolar epithelial cells. Unlike some subgroup 2b SARS-CoV vaccines that elicit a strong eosinophilia following challenge, we demonstrate that BtCoV HKU5 and MERS-CoV N-expressing Venezuelan equine encephalitis virus replicon particle (VRP) vaccines do not cause extensive eosinophilia following BtCoV HKU5-SE challenge. Passage of BtCoV HKU5-SE in young mice resulted in enhanced virulence, causing 20% weight loss, diffuse alveolar damage, and hyaline membrane formation in aged mice. Passaged virus was characterized by mutations in the nsp13, nsp14, open reading frame 5 (ORF5) and M genes. Finally, we identified an inhibitor active against the nsp5 proteases of subgroup 2c β-CoVs. Synthetic-genome platforms capable of reconstituting emerging zoonotic viral pathogens or their phylogenetic relatives provide new strategies for identifying broad-based therapeutics, evaluating vaccine outcomes, and studying viral pathogenesis.

negative: Lactogenic immunity following vaccination of cattle with bovine coronavirus Abstract In order to investigate the ability of an oil adjuvanted vaccine containing bovine coronavirus antigen to enhance lactogenic immunity in the calf, pregnant cows and heifers were vaccinated and specific virus neutralising antibody levels determined in serum, colostrum and milk. Pre-existing antibody titres (as a result of natural infection) in the serum of these animals were found to be significantly increased as a result of a single shot vaccination carried out between 2 and 12 weeks before calving. This was reflected in a similar increase in the titre and duration of specific antibody in milk and colostrum that was passed on to the calves. The overall response observed was highly dependent on an adequate antigen payload being incorporated within the single dose vaccine. No abnormal local or systemic reactions were observed as a result of vaccination. It is hoped that this approach will lead to the production of a superior commercial vaccine for the protection of neonatal calves against enteric coronavirus infection.

negative: Speculation is not evidence: antihypertensive therapy and COVID-19

negative: Structure, function and antigenicity of the SARS-CoV-2 spike glycoprotein The recent emergence of a novel coronavirus associated with an ongoing outbreak of pneumonia (Covid-2019) resulted in infections of more than 72,000 people and claimed over 1,800 lives. Coronavirus spike (S) glycoprotein trimers promote entry into cells and are the main target of the humoral immune response. We show here that SARS-CoV-2 S mediates entry in VeroE6 cells and in BHK cells transiently transfected with human ACE2, establishing ACE2 as a functional receptor for this novel coronavirus. We further demonstrate that the receptor-binding domains of SARS-CoV-2 S and SARS-CoV S bind with similar affinities to human ACE2, which correlates with the efficient spread of SARS-CoV-2 among humans. We found that the SARS-CoV-2 S glycoprotein harbors a furin cleavage site at the boundary between the S1/S2 subunits, which is processed during biogenesis and sets this virus apart from SARS-CoV and other SARS-related CoVs. We determined a cryo-electron microscopy structure of the SARS-CoV-2 S ectodomain trimer, demonstrating spontaneous opening of the receptor-binding domain, and providing a blueprint for the design of vaccines and inhibitors of viral entry. Finally, we demonstrate that SARS-CoV S murine polyclonal sera potently inhibited SARS-CoV-2 S-mediated entry into target cells, thereby indicating that cross-neutralizing antibodies targeting conserved S epitopes can be elicited upon vaccination.

negative: What Have We Learned About Middle East Respiratory Syndrome Coronavirus Emergence in Humans? A Systematic Literature Review Background: Middle East respiratory syndrome coronavirus (MERS-CoV) was first identified in humans in 2012. A systematic literature review was conducted to synthesize current knowledge and identify critical knowledge gaps. Materials and Methods: We conducted a systematic review on MERS-CoV using PRISMA guidelines. We identified 407 relevant, peer-reviewed publications and selected 208 of these based on their contributions to four key areas: virology; clinical characteristics, outcomes, therapeutic and preventive options; epidemiology and transmission; and animal interface and the search for natural hosts of MERS-CoV. Results: Dipeptidyl peptidase 4 (DPP4/CD26) was identified as the human receptor for MERS-CoV, and a variety of molecular and serological assays developed. Dromedary camels remain the only documented zoonotic source of human infection, but MERS-like CoVs have been detected in bat species globally, as well as in dromedary camels throughout the Middle East and Africa. However, despite evidence of camel-to-human MERS-CoV transmission and cases apparently related to camel contact, the source of many primary cases remains unknown. There have been sustained health care-associated human outbreaks in Saudi Arabia and South Korea, the latter originating from one traveler returning from the Middle East. Transmission mechanisms are poorly understood; for health care, this may include environmental contamination. Various potential therapeutics have been identified, but not yet evaluated in human clinical trials. At least one candidate vaccine has progressed to Phase I trials. Conclusions: There has been substantial MERS-CoV research since 2012, but significant knowledge gaps persist, especially in epidemiology and natural history of the infection. There have been few rigorous studies of baseline prevalence, transmission, and spectrum of disease. Terms such as “camel exposure” and the epidemiological relationships of cases should be clearly defined and standardized. We strongly recommend a shared and accessible registry or database. Coronaviruses will likely continue to emerge, arguing for a unified “One Health” approach.

negative: Proteolytic Disassembly Is a Critical Determinant for Reovirus Oncolysis See page 1406 Mammalian ortheoreoviruses are currently being investigated as novel cancer therapeutics, but the cellular mechanisms that regulate susceptibility to reovirus oncolysis remain poorly understood. In this study, we present evidence that virion disassembly is a key determinant of reovirus oncolysis. To penetrate cell membranes and initiate infection, the outermost capsid proteins of reovirus must be proteolyzed to generate a disassembled particle called an infectious subviral particle (ISVP). In fibroblasts, this process is mediated by the endo/lysosomal proteases cathepsins B and L. We have analyzed the early events of infection in reovirus-susceptible and -resistant cells. We find that, in contrast to susceptible glioma cells and Ras-transformed NIH3T3 cells, reovirus-resistant cancer cells and untransformed NIH3T3 cells restrict virion uncoating and subsequent gene expression. Disassembly-restrictive cells support reovirus infection, as in vitro-generated ISVPs establish productive infection, and pretreatment with poly(I:C) does not prevent infection in cancer cells. We find that the level of active cathepsin B and L is increased in tumors and that disassembly-restrictive glioma cells support reovirus oncolysis when grown as a tumor in vivo. Together, these results provide a model in which proteolytic disassembly of reovirus is a critical determinant of susceptibility to reovirus oncolysis.

negative: From SARS to MERS: 10 years of research on highly pathogenic human coronaviruses Abstract This article introduces a series of invited papers in Antiviral Research marking the 10th anniversary of the outbreak of severe acute respiratory syndrome (SARS), caused by a novel coronavirus that emerged in southern China in late 2002. Until that time, coronaviruses had not been recognized as agents causing severe disease in humans, hence, the emergence of the SARS-CoV came as a complete surprise. Research during the past ten years has revealed the existence of a diverse pool of coronaviruses circulating among various bat species and other animals, suggesting that further introductions of highly pathogenic coronaviruses into the human population are not merely probable, but inevitable. The recent emergence of another coronavirus causing severe disease, Middle East respiratory syndrome (MERS), in humans, has made it clear that coronaviruses pose a major threat to human health, and that more research is urgently needed to elucidate their replication mechanisms, identify potential drug targets, and develop effective countermeasures. In this series, experts in many different aspects of coronavirus replication and disease will provide authoritative, up-to-date reviews of the following topics: – clinical management and infection control of SARS; – reservoir hosts of coronaviruses; – receptor recognition and cross-species transmission of SARS-CoV; – SARS-CoV evasion of innate immune responses; – structures and functions of individual coronaviral proteins; – anti-coronavirus drug discovery and development; and – the public health legacy of the SARS outbreak. Each article will be identified in the last line of its abstract as belonging to the series “From SARS to MERS: 10years of research on highly pathogenic human coronaviruses.”

negative: Teicoplanin: an alternative drug for the treatment of coronavirus COVID-19? In December 2019, a new coronavirus, named SARS-CoV-2, has emerged from China causing pneumonia outbreaks first in the Wuhan region and have now spread worldwide because of its probable high transmission efficiency. Due to the lack of efficient and specific treatments and the need to contain the epidemic, drug repurposing appears to be the best tool to find therapeutic solution. Chloroquine, remdesivir, lopinavir, ribavirin or ritonavir have shown efficacy to inhibit coronavirus in vitro. Teicoplanin, an antibiotic used to treat staphylococci infection, previously showed efficacy to inhibit the first stage of MERS-coronarivus viral cycle in human cells. This activity is conserved on the SARS-Cov-2, thus placing teicoplanin as a potential treatment for patients with this virus.

negative: Endoplasmic reticulum as a potential therapeutic target for covid-19 infection management? In December 2019, many pneumonia cases with unidentified sources appeared in Wuhan, Hubei, China, with clinical symptoms like viral pneumonia. Deep sequencing analysis of samples from lower respiratory tract revealed a novel coronavirus, called 2019 novel coronavirus (2019-nCoV). Currently there is a rapid global spread. World Health Organization declare the disease a pandemic condition. The pathologic source of this disease was a new RNA virus from Coronaviridae family, which was named COVID-19. SARS-CoV-2 entry starts with the binding of the spike glycoprotein expressed on the viral envelope to ACE2 on the alveolar surface followed by clathrin-dependent endocytosis of the SARS-CoV-2 and ACE2 complex. SARS-CoV-2 enters the cells through endocytosis process, which is possibly facilitated, via a pH dependent endosomal cysteine protease cathepsins. Once inside the cells, SARS-CoV-2 exploits the endogenous transcriptional machinery of alveolar cells to replicate and spread through the entire lung. Endosomal acidic pH for SARS-CoV-2 processing and internalization is critical. After entering the cells, it possibly activates or hijack many intracellular pathways in favor of its replication. In the current opinion article, we will explain the possible involvement of unfolded protein response as a cellular stress response to the SARS-CoV-2 infection.

negative: Long-lived effector/central memory T-cell responses to severe acute respiratory syndrome coronavirus (SARS-CoV) S antigen in recovered SARS patients Abstract The role of cell-mediated immunity in human SARS-CoV infection is still not well understood. In this study, we found that memory T-cell responses against the spike (S) protein were persistent for more than 1 year after SARS-CoV infection by detecting the production of IFN-γ using ELISA and ELISpot assays. Flow cytometric analysis showed that both CD4+ and CD8+ T cells were involved in cellular responses against SARS-CoV infection. Interestingly, most of SARS-CoV S-specific memory CD4+ T cells were central memory cells expressing CD45RO+ CCR7+ CD62L−. However, the majority of memory CD8+ T cells revealed effector memory phenotype expressing CD45RO− CCR7− CD62L−. Thus, our study provides the evidence that SARS-CoV infection in humans can induce cellular immune response that is persistent for a long period of time. These data may have an important implication in the possibility of designing effective vaccine against SARS-CoV infection, specifically in defining T-cell populations that are implicated in protective immunity.

negative: Scientific Opinion on porcine epidemic diarrhoea and emerging porcine deltacoronavirus In the last decade, many porcine epidemic diarrhoea (PED) outbreaks have been reported by several countries in Asia whereas only a few Member States of the European Union (EU) have reported PED clinical cases and/or PED virus (PEDV)‐seropositive animals. This alphacoronavirus was first reported in the USA in May 2013, followed by rapid spread throughout the country and outbreaks reported by several countries in the Americas. The recent PEDV‐EU isolates have high level of sequence identity to PEDV‐Am isolates. Based on nucleotide sequencing, multiple variants of PEDV are circulating in Europe, the Americas and Asia but any difference in virulence and antigenicity is currently unknown. Serological cross‐reactivity has been reported between PEDV isolated in Europe and in the Americas; however no data regarding cross‐protection are available. The impact of different PEDV strains is difficult to compare between one country and another, since impact is dependent not only on pathogenicity but also on factors such as biosecurity, farm management, sanitary status or herd immune status. However, the clinical signs of PEDV infections in naive pigs are similar in different countries with mortalities up to 100% in naive newborn piglets. The impact of recently reported PED outbreaks in Asia and the USA seems to be more severe than what has been described in Europe. Infected animals, faeces, feed and objects contaminated with faeces are matrices that have been reported to transmit PEDV between farms. Infectious PEDV has been detected in spray‐dried porcine plasma (SDPP) in one study but the origin of the infectious PEDV in SDPP is not clear. Detection of porcine deltacoronavirus (PDCoV) has been reported in a few countries but only limited testing has been done. Based on the currently available information, it seems that PDCoV would have a lower impact than PEDV.

negative: Severe Acute Respiratory Syndrome Coronavirus Nonstructural Proteins 3, 4, and 6 Induce Double-Membrane Vesicles Coronaviruses (CoV), like other positive-stranded RNA viruses, redirect and rearrange host cell membranes for use as part of the viral genome replication and transcription machinery. Specifically, coronaviruses induce the formation of double-membrane vesicles in infected cells. Although these double-membrane vesicles have been well characterized, the mechanism behind their formation remains unclear, including which viral proteins are responsible. Here, we use transfection of plasmid constructs encoding full-length versions of the three transmembrane-containing nonstructural proteins (nsps) of the severe acute respiratory syndrome (SARS) coronavirus to examine the ability of each to induce double-membrane vesicles in tissue culture. nsp3 has membrane disordering and proliferation ability, both in its full-length form and in a C-terminal-truncated form. nsp3 and nsp4 working together have the ability to pair membranes. nsp6 has membrane proliferation ability as well, inducing perinuclear vesicles localized around the microtubule organizing center. Together, nsp3, nsp4, and nsp6 have the ability to induce double-membrane vesicles that are similar to those observed in SARS coronavirus-infected cells. This activity appears to require the full-length form of nsp3 for action, as double-membrane vesicles were not seen in cells coexpressing the C-terminal truncation nsp3 with nsp4 and nsp6.

negative: FIP and coronavirus 7b protein antibodies

negative: Glycan repositioning of influenza hemagglutinin stem facilitates the elicitation of protective cross-group antibody responses The conserved hemagglutinin (HA) stem has been a focus of universal influenza vaccine efforts. Influenza A group 1 HA stem-nanoparticles have been demonstrated to confer heterosubtypic protection in animals; however, the protection does not extend to group 2 viruses, due in part to differences in glycosylation between group 1 and 2 stems. Here, we show that introducing the group 2 glycan at Asn38(HA1) to a group 1 stem-nanoparticle (gN38 variant) based on A/New Caledonia/20/99 (H1N1) broadens antibody responses to cross-react with group 2 HAs. Immunoglobulins elicited by the gN38 variant provide complete protection against group 2 H7N9 virus infection, while the variant loses protection against a group 1 H5N1 virus. The N38(HA1) glycan thus is pivotal in directing antibody responses by controlling access to group-determining stem epitopes. Precise targeting of stem-directed antibody responses to the site of vulnerability by glycan repositioning may be a step towards achieving cross-group influenza protection.

negative: Probable Pangolin Origin of SARS-CoV-2 Associated with the COVID-19 Outbreak An outbreak of coronavirus disease 2019 (COVID-19) caused by the 2019 novel coronavirus (SARS-CoV-2) began in the city of Wuhan in China and has widely spread worldwide. Currently, it is vital to explore potential intermediate hosts of SARS-CoV-2 to control COVID-19 spread. Therefore, we reinvestigated published data from pangolin lung samples from which SARS-CoV-like CoVs were detected by Liu et al. [1]. We found genomic and evolutionary evidence of the occurrence of a SARS-CoV-2-like CoV (named Pangolin-CoV) in dead Malayan pangolins. Pangolin-CoV is 91.02% and 90.55% identical to SARS-CoV-2 and BatCoV RaTG13, respectively, at the whole-genome level. Aside from RaTG13, Pangolin-CoV is the most closely related CoV to SARS-CoV-2. The S1 protein of Pangolin-CoV is much more closely related to SARS-CoV-2 than to RaTG13. Five key amino acid residues involved in the interaction with human ACE2 are completely consistent between Pangolin-CoV and SARS-CoV-2, but four amino acid mutations are present in RaTG13. Both Pangolin-CoV and RaTG13 lost the putative furin recognition sequence motif at S1/S2 cleavage site that can be observed in the SARS-CoV-2. Conclusively, this study suggests that pangolin species are a natural reservoir of SARS-CoV-2-like CoVs.

negative: KAPITEL 13 Infektionskrankheiten Zur Orientierung Infektionskrankheiten werden durch Pathogene verursacht, die sich im Wirt vermehren: Ektoparasiten, Helminthen, Protozoen, Pilze, Bakterien, Viren, Prionen. Infektionskrankheiten können alle Organe bzw. Organsysteme befallen. Entstehung und Verlauf werden durch Faktoren beeinflusst, die sich grob einteilen lassen in Erreger- und Wirtsfaktoren. Die Kenntnis und richtige Einschätzung dieser Faktoren sind entscheidend für Diagnostik und Therapie dieser Erkrankungen.

negative: Letter to the Editor concerning A study on infectivity of asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) carriers by Gao et al

negative: Severe acute respiratory syndrome and dentistry A retrospective view ABSTRACT Background Severe acute respiratory syndrome, or SARS, which has created panic in Asia and in some parts of North America, is the first epidemic of the new century. Although it has been well-contained, sporadic cases continue to emerge. Objectives The authors trace the emergence of the SARS outbreak from southern China and its spread worldwide, discuss the viral etiology of the infection and its clinical features, and review the infection control guidelines issued during the outbreak by the health authorities in Hong Kong, the Centers for Disease Control and Prevention, the World Health Organization and the American Dental Association. They also review the prospects for a new outbreak and preventive measures. Overview The disease, which is caused by a novel coronavirus termed the “SARS coronavirus,” or SARS-CoV, essentially spreads through droplet infection and affects people of any age. It has a mortality rate ranging from 10 to 15 percent. A major hallmark of this disease has been the rate at which it has affected health care workers through nosocomial transmission; in some countries, up to one-fourth to one-third of those infected were in this category. However, no dental health care worker has been affected by SARS in a nosocomial or dental setting. Conclusions and Clinical Implications Researchers believe that a combination of factors, including the universal infection control measures that the dental community has implemented and/or the low degree of viral shedding in the prodromal phase of SARS, may have obviated the spread of the disease in dental settings. The dental community should reflect on this outbreak to reinforce the currently applied infection control measures.

negative: Human Coronaviruses: A Review of Virus–Host Interactions Human coronaviruses (HCoVs) are known respiratory pathogens associated with a range of respiratory outcomes. In the past 14 years, the onset of severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV) have thrust HCoVs into spotlight of the research community due to their high pathogenicity in humans. The study of HCoV-host interactions has contributed extensively to our understanding of HCoV pathogenesis. In this review, we discuss some of the recent findings of host cell factors that might be exploited by HCoVs to facilitate their own replication cycle. We also discuss various cellular processes, such as apoptosis, innate immunity, ER stress response, mitogen-activated protein kinase (MAPK) pathway and nuclear factor kappa B (NF-κB) pathway that may be modulated by HCoVs.

negative: Chapter 7 Coronaviridae: 100,000 Years of Emergence and Reemergence Abstract The coronavirus family (Coronaviridae) is a positive-sense single-stranded RNA, with a size of 27kb. These viruses have a potential species specificity and interspecies transmission. The interspecies transmission of viruses from one host species to another is a major factor responsible for the majority of emerging and reemerging infections. The Coronaviridae is one of the most popular emerging viral families that threaten to the public health.

negative: Possible therapeutic role of a highly standardized mixture of active compounds derived from cultured Lentinula edodes mycelia (AHCC) in patients infected with 2019 novel coronavirus. The outbreak of SARS-CoV-2 disease (COVID-19) is currently, March 2020, affecting more than 100000 people worldwide and, according to the WHO (World Health Organization), a pandemic is shortly expected. The virus infects the lower respiratory tract and causes severe pneumonia and mortality in approximately 10% and 3-5%, respectively, of cases, mainly among the elderly and/or people affected by other diseases. AHCC is an α-glucan-based standardized mushroom extract that has been extensively investigated as an immunostimulant both in animals and/or in humans affected by West Nile virus, influenza virus, avian influenza virus, hepatitis C virus, papillomavirus, herpes virus, hepatitis B virus and HIV by promoting a regulated and protective immune response. Although the efficacy of AHCC has not yet been specifically evaluated with respect to SARS-CoV-2 disease, its action in promoting a protective response to a wide range of viral infections, and the current absence of effective vaccines, could support its use in the prevention of diseases provoked by human pathogenic coronavirus, including COVID-19.

negative: How to protect the protectors: 10 lessons to learn for doctors fighting the COVID-19 coronavirus

negative: SARS-CoV-2 and DPP4 inhibition: is it time to pray for Janus Bifrons? Abstract Diabetes could be a risk factor for severity and mortality in patients with coronavirus disease 2019 Covid-19. It has been hypothesized that DPP4 inhibition, a therapy currently available for type 2 diabetes, might represent a target for decreasing the risk of the acute respiratory complications of the COVID-19 infection but 1) lack of demonstration of SARS-CoV2 binding to DPP4 2) possible protective role of sDPP4 in Middle East respiratory Syndrome (MERS-CoV 3) demonstrated inhibition and downregulation of DPP4 by HIV1 and MERS-CoV and 4) not exclusive role of the receptor binding in tropism of the Coronavirus family, support that DPP4 inhibition at present doesn’t represent a plausible approach to mitigate Covid-19.

negative: A Rapid Advice Guideline for the Prevention of Novel Coronavirus Through Nutritional Intervention PURPOSE OF REVIEW: An unexpected and sudden outbreak of a novel infection known as a coronavirus (COVID-19) has imposed important problems to global well-being and economy. Based upon current researches, this virus is spreading from one human to another through respiratory droplets, i.e. cough and sneeze. Till now, there has not been any specific treatment found for this virus. Hence, there is a critical need to discover alternative techniques to cope with the current scenario. RECENT FINDINGS: This review conducted an online search for prevention of coronavirus infection with the help of nutritional interventions. It has been observed that the effect of the virus is mostly on the individual with low immunity, individual affected with diseases like diabetes, and individual using any immune-suppressed drug or having past history of major surgeries or severe medical conditions. SUMMARY: Therefore, consuming foods which boost immunity helps in preventing respiratory-related disorder or suppressing diseases-related problems, which could be helpful in controlling the spread of this virus. In conclusion, it has been suggested that before the beginning of generalised treatments and interventions in each infected patient, nutritional status should be evaluated, as it can help in creating a specific nutrition intervention for the infected individual.

negative: Emerging Influenza and Psychosis: An Important Story in Psychological Medicine

negative: Intragastric administration of Lactobacillus casei expressing transmissible gastroentritis coronavirus spike glycoprotein induced specific antibody production Lactobacillus casei strain Shirota was selected as a bacterial carrier for the development of live mucosal vaccines against coronavirus. A 75 kDa fragment of transmissible gastroenteritis coronavirus (TGEV) spike glycoprotein S was used as the model coronavirus antigen. The S glycoprotein was cloned into a Lactobacillus/E. coli shuttle vector (pLP500) where expression and secretion of the glycoprotein S from the recombinant lactobacilli was detected via immunoblotting. Oral immunization of BALB/c mice with recombinant LcS that constitutively expresses the 75 kDa fragment of the glycoprotein S, induced both local mucosal and systemic immune responses against TGEV. Maximum titers of IgG (8.38 ± 0.19 ng/ml of serum) and IgA (64.82 ± 2.9 ng/ml of intestinal water) were attained 32 days post oral inturbation. The induced antibodies demonstrated neutralizing effects on TGEV infection.

negative: Potential risks of SARS-Cov-2 infection on reproductive health Abstract The outbreak of 2019 novel coronavirus disease (COVID-19) has been a major epidemic threat all over the world. Such a public health emergency can greatly impact various aspects of people's health and lives. This paper focused on its potential risks on reproductive health, including reproductive system and function, as well as gamete and embryo development, which was underpinned by the virus, drugs, chemical disinfectants and panic psychology during the outbreak of COVID-19.

negative: Structural genomics and interactomics of 2019 Wuhan novel coronavirus, 2019-nCoV, indicate evolutionary conserved functional regions of viral proteins During its first month, the recently emerged 2019 Wuhan novel coronavirus (2019-nCoV) has already infected many thousands of people in mainland China and worldwide and took hundreds of lives. However, the swiftly spreading virus also caused an unprecedentedly rapid response from the research community facing the unknown health challenge of potentially enormous proportions. Unfortunately, the experimental research to understand the molecular mechanisms behind the viral infection and to design a vaccine or antivirals is costly and takes months to develop. To expedite the advancement of our knowledge we leverage the data about the related coronaviruses that is readily available in public databases, and integrate these data into a single computational pipeline. As a result, we provide a comprehensive structural genomics and interactomics road-maps of 2019-nCoV and use these information to infer the possible functional differences and similarities with the related SARS coronavirus. All data are made publicly available to the research community at http://korkinlab.org/wuhan

negative: Positive rate of RT-PCR detection of SARS-CoV-2 infection in 4880 cases from one hospital in Wuhan, China, from Jan to Feb 2020 Abstract Background There’s an outbreak of a novel coronavirus (SARS-CoV-2) infection since December 2019, first in China, and currently with more than 80 thousand confirmed infection globally in 29 countries till March 2, 2020. Identification, isolation and caring for patients early are essential to limit human-to-human transmission including reducing secondary infections among close contacts and health care workers, preventing transmission amplification events. The RT-PCR detection of viral nucleic acid test (NAT) was one of the most quickly established laboratory diagnosis method in a novel viral pandemic, just as in this COVID-19 outbreak. Methods 4880 cases that had respiratory infection symptoms or close contact with COVID-19 patients in hospital in Wuhan, China, were tested for SARS-CoV-2 infection by use of quantitative RT-PCR (qRT-PCR) on samples from the respiratory tract. Positive rates were calculated in groups divided by genders or ages. Results The positive rate was about 38% for the total 4880 specimens. Male and older population had a significant higher positive rates. However, 57% was positive among the specimens from the Fever Clinics. Binary logistic regression analysis showed that age, not gender, was the risk factor for SARS-CoV-2 infection in fever clinics. Conclusions Therefore, we concluded that viral NAT played an important role in identifying SARS-CoV-2 infection.

negative: Human metapneumovirus: review of an important respiratory pathogen Summary Human metapneumovirus (hMPV), discovered in 2001, most commonly causes upper and lower respiratory tract infections in young children, but is also a concern for elderly subjects and immune-compromised patients. hMPV is the major etiological agent responsible for about 5% to 10% of hospitalizations of children suffering from acute respiratory tract infections. hMPV infection can cause severe bronchiolitis and pneumonia in children, and its symptoms are indistinguishable from those caused by human respiratory syncytial virus. Initial infection with hMPV usually occurs during early childhood, but re-infections are common throughout life. Due to the slow growth of the virus in cell culture, molecular methods (such as reverse transcriptase PCR (RT-PCR)) are the preferred diagnostic modality for detecting hMPV. A few vaccine candidates have been shown to be effective in preventing clinical disease, but none are yet commercially available. Our understanding of hMPV has undergone major changes in recent years and in this article we will review the currently available information on the molecular biology and epidemiology of hMPV. We will also review the current therapeutic interventions and strategies being used to control hMPV infection, with an emphasis on possible approaches that could be used to develop an effective vaccine against hMPV.

negative: Beneficial and Detrimental Effects of Regulatory T Cells in Neurotropic Virus Infections Neurotropic viruses infect the central nervous system (CNS) and cause acute or chronic neurologic disabilities. Regulatory T cells (Treg) play a critical role for immune homeostasis, but may inhibit pathogen-specific immunity in infectious disorders. The present review summarizes the current knowledge about Treg in human CNS infections and their animal models. Besides dampening pathogen-induced immunopathology, Treg have the ability to facilitate protective responses by supporting effector T cell trafficking to the infection site and the development of resident memory T cells. Moreover, Treg can reduce virus replication by inducing apoptosis of infected macrophages and attenuate neurotoxic astrogliosis and pro-inflammatory microglial responses. By contrast, detrimental effects of Treg are caused by suppression of antiviral immunity, allowing for virus persistence and latency. Opposing disease outcomes following Treg manipulation in different models might be attributed to differences in technique and timing of intervention, infection route, genetic background, and the host’s age. In addition, mouse models of virus-induced demyelination revealed that Treg are able to reduce autoimmunity and immune-mediated CNS damage in a disease phase-dependent manner. Understanding the unique properties of Treg and their complex interplay with effector cells represents a prerequisite for the development of new therapeutic approaches in neurotropic virus infections.

negative: Integrate Structural Analysis, Isoform Diversity, and Interferon-Inductive Propensity of ACE2 to Refine SARS-CoV2 Susceptibility Prediction in Vertebrates The current new coronavirus disease (COVID-19) has caused globally near 0.4/6 million confirmed deaths/infected cases across more than 200 countries. As the etiological coronavirus (a.k.a. SARS-CoV2) may putatively have a bat origin, our understanding about its intermediate reservoir between bats and humans, especially its tropism in wild and domestic animals, are mostly unknown. This constitutes major concerns in public health for the current pandemics and potential zoonosis. Previous reports using structural analysis of the viral spike protein (S) binding its cell receptor of angiotensin-converting enzyme 2 (ACE2), indicate a broad SARS-CoV2 susceptibility in wild and particularly domestic animals. Through integration of key immunogenetic factors, including the existence of S-binding-void ACE2 isoforms and the disparity of ACE2 expression upon early innate immune response, we further refine the SARS-CoV2 susceptibility prediction to fit recent experimental validation. In addition to showing a broad susceptibility potential across mammalian species based on structural analysis, our results also reveal that domestic animals including dogs, pigs, cattle and goats may evolve ACE2-related immunogenetic diversity to restrict SARS-CoV2 infections. Thus, we propose that domestic animals may be unlikely to play a role as amplifying hosts unless the virus has further species-specific adaptation. These findings may relieve relevant public concerns regarding COVID-19-like risk in domestic animals, highlight virus-host coevolution, and evoke disease intervention through targeting ACE2 molecular diversity and interferon optimization.

negative: Comparison of SARS-CoV2 N gene real-time RT-PCR targets and commercially available mastermixes We aim to test four one-step RT real-time mastermix options for use in SARS-CoV2 real-time PCR, with three primer/probe assays targeting the N gene. The lower limit of detection is determined using a SARS CoV2 N gene RNA transcript dilution series (to 1 copy/µl) and verified using 74 nose and throat swabs. The N2 assay demonstrates the most sensitive detection of SARS-Cov-2 RNA. Three of the four mastermixes performed well, with the Takara One Step PrimeScript™ III RT-PCR Kit mastermix demonstrating improved performance at the lower limit of detection.

negative: The Emerging Role of Rhinoviruses in Lower Respiratory Tract Infections in Children – Clinical and Molecular Epidemiological Study From Croatia, 2017–2019 Rhinoviruses (RVs) are increasingly implicated not only in mild upper respiratory tract infections, but also in more severe lower respiratory tract infections; however, little is known about species diversity and viral epidemiology of RVs among the infected children. Therefore, we investigated the rhinovirus (RV) infection prevalence over a 2-year period, compared it with prevalence patterns of other common respiratory viruses, and explored clinical and molecular epidemiology of RV infections among 590 children hospitalized with acute respiratory infection in north-western and central parts of Croatia. For respiratory virus detection, nasopharyngeal and pharyngeal flocked swabs were taken from each patient and subsequently analyzed with multiplex RT-PCR. To determine the RV species in a subset of positive children, 5′UTR in RV-positive samples has been sequenced. Nucleotide sequences of referent RV strains were retrieved by searching the database with Basic Local Alignment Tool, and used to construct alignments and phylogenetic trees using MAFFT multiple sequence alignment tool and the maximum likelihood method, respectively. In our study population RV was the most frequently detected virus, diagnosed in 197 patients (33.4%), of which 60.4% was detected as a monoinfection. Median age of RV-infected children was 2.25 years, and more than half of children infected with RV (55.8%) presented with lower respiratory tract infections. Most RV cases were detected from September to December, and all three species co-circulated during the analyzed period (2017–2019). Sequence analysis based on 5′UTR region yielded 69 distinct strains; the most prevalent was RV-C (47.4%) followed by RV-A (44.7%) and RV-B (7.9%). Most of RV-A sequences formed a distinct phylogenetic group; only strains RI/HR409-18 (along with a reference strain MF978777) clustered with RV-C strains. Strains belonging to the group C were the most diverse (41.6% identity among strains), while group B was the most conserved (71.5% identity among strains). Despite such differences in strain groups (hitherto undescribed in Croatia), clinical presentation of infected children was rather similar. Our results are consistent with newer studies that investigated the etiology of acute respiratory infections, especially those focused on children with lower respiratory tract infections, where RVs should always be considered as potentially serious pathogens.

negative: Middle East Respiratory Syndrome Coronavirus (MERS-CoV): Infection, Immunological Response, and Vaccine Development Middle East respiratory syndrome coronavirus (MERS-CoV) first emerged in late 2012. Since its emergence, a total of 2279 patients from 27 countries have been infected across the globe according to a World Health Organization (WHO) report (Feb. 12th, 2019). Approximately 806 patients have died. The virus uses its spike proteins as adhesive factors that are proinflammatory for host entry through a specific receptor called dipeptidyl peptidase-4 (DPP4). This receptor is considered a key factor in the signaling and activation of the acquired and innate immune responses in infected patients. Using potent antigens in combination with strong adjuvants may effectively trigger the activation of specific MERS-CoV cellular responses as well as the production of neutralizing antibodies. Unfortunately, to date, there is no effective approved treatment or vaccine for MERS-CoV. Thus, there are urgent needs for the development of novel MERS-CoV therapies as well as vaccines to help minimize the spread of the virus from infected patients, thereby mitigating the risk of any potential pandemics. Our main goals are to highlight and describe the current knowledge of both the innate and adaptive immune responses to MERS-CoV and the current state of MERS-CoV vaccine development. We believe this study will increase our understanding of the mechanisms that enhance the MERS-CoV immune response and subsequently contribute to the control of MERS-CoV infections.

negative: Genome-wide screening of lipoproteins in Actinobacillus pleuropneumoniae identifies three antigens that confer protection against virulent challenge Actinobacillus pleuropneumoniae is an important veterinary pathogen that causes porcine pleuropneumonia. Lipoproteins of bacterial pathogens play pleiotropic roles in the infection process. In addition, many bacterial lipoproteins are antigenic and immunoprotective. Therefore, characterization of lipoproteins is a promising strategy for identification of novel vaccine candidates or diagnostic markers. We cloned 58 lipoproteins from A. pleuropneumoniae JL03 (serovar 3) and expressed them in Escherichia coli. Five proteins with strong positive signals in western blotting analysis were used to immunize mice. These proteins elicited significant antibody responses, and three of them (APJL_0922, APJL_1380 and APJL_1976) generated efficient immunoprotection in mice against lethal heterologous challenge with A. pleuropneumoniae 4074 (serovar 1), both in the active and passive immunization assays. Then immunogenicity of these three lipoproteins (APJL_0922, APJL_1380 and APJL_1976) were further tested in pigs. Results showed that these proteins elicited considerable humoral immune responses and effective protective immunity against virulent A. pleuropneumoniae challenge. Our findings suggest that these three novel lipoproteins could be potential subunit vaccine candidates.

negative: Associations between immune-suppressive and stimulating drugs and novel COVID-19—a systematic review of current evidence BACKGROUND: Cancer and transplant patients with COVID-19 have a higher risk of developing severe and even fatal respiratory diseases, especially as they may be treated with immune-suppressive or immune-stimulating drugs. This review focuses on the effects of these drugs on host immunity against COVID-19. METHODS: Using Ovid MEDLINE, we reviewed current evidence for immune-suppressing or -stimulating drugs: cytotoxic chemotherapy, low-dose steroids, tumour necrosis factorα (TNFα) blockers, interlukin-6 (IL-6) blockade, Janus kinase (JAK) inhibitors, IL-1 blockade, mycophenolate, tacrolimus, anti-CD20 and CTLA4-Ig. RESULTS: 89 studies were included. Cytotoxic chemotherapy has been shown to be a specific inhibitor for severe acute respiratory syndrome coronavirus in in vitro studies, but no specific studies exist as of yet for COVID-19. No conclusive evidence for or against the use of non-steroidal anti-inflammatory drugs (NSAIDs) in the treatment of COVID-19 patients is available, nor is there evidence indicating that TNFα blockade is harmful to patients in the context of COVID-19. COVID-19 has been observed to induce a pro-inflammatory cytokine generation and secretion of cytokines, such as IL-6, but there is no evidence of the beneficial impact of IL-6 inhibitors on the modulation of COVID-19. Although there are potential targets in the JAK-STAT pathway that can be manipulated in treatment for coronaviruses and it is evident that IL-1 is elevated in patients with a coronavirus, there is currently no evidence for a role of these drugs in treatment of COVID-19. CONCLUSION: The COVID-19 pandemic has led to challenging decision-making about treatment of critically unwell patients. Low-dose prednisolone and tacrolimus may have beneficial impacts on COVID-19. The mycophenolate mofetil picture is less clear, with conflicting data from pre-clinical studies. There is no definitive evidence that specific cytotoxic drugs, low-dose methotrexate for auto-immune disease, NSAIDs, JAK kinase inhibitors or anti-TNFα agents are contraindicated. There is clear evidence that IL-6 peak levels are associated with severity of pulmonary complications.

negative: Varicella zoster infection and IgG antibody formation in a 10-week-old preterm infant despite maternal immunity

negative: Comparative tropism, replication kinetics, and cell damage profiling of SARS-CoV-2 and SARS-CoV with implications for clinical manifestations, transmissibility, and laboratory studies of COVID-19: an observational study Summary Background Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was reported from China in January, 2020. SARS-CoV-2 is efficiently transmitted from person to person and, in 2 months, has caused more than 82 000 laboratory-confirmed cases of coronavirus disease 2019 (COVID-19) and 2800 deaths in 46 countries. The total number of cases and deaths has surpassed that of the 2003 severe acute respiratory syndrome coronavirus (SARS-CoV). Although both COVID-19 and severe acute respiratory syndrome (SARS) manifest as pneumonia, COVID-19 is associated with apparently more efficient transmission, fewer cases of diarrhoea, increased mental confusion, and a lower crude fatality rate. However, the underlying virus–host interactive characteristics conferring these observations on transmissibility and clinical manifestations of COVID-19 remain unknown. Methods We systematically investigated the cellular susceptibility, species tropism, replication kinetics, and cell damage of SARS-CoV-2 and compared findings with those for SARS-CoV. We compared SARS-CoV-2 and SARS-CoV replication in different cell lines with one-way ANOVA. For the area under the curve comparison between SARS-CoV-2 and SARS-CoV replication in Calu3 (pulmonary) and Caco2 (intestinal) cells, we used Student's t test. We analysed cell damage induced by SARS-CoV-2 and SARS-CoV with one-way ANOVA. Findings SARS-CoV-2 infected and replicated to comparable levels in human Caco2 cells and Calu3 cells over a period of 120 h (p=0·52). By contrast, SARS-CoV infected and replicated more efficiently in Caco2 cells than in Calu3 cells under the same multiplicity of infection (p=0·0098). SARS-CoV-2, but not SARS-CoV, replicated modestly in U251 (neuronal) cells (p=0·036). For animal species cell tropism, both SARS-CoV and SARS-CoV-2 replicated in non-human primate, cat, rabbit, and pig cells. SARS-CoV, but not SARS-CoV-2, infected and replicated in Rhinolophus sinicus bat kidney cells. SARS-CoV-2 consistently induced significantly delayed and milder levels of cell damage than did SARS-CoV in non-human primate cells (VeroE6, p=0·016; FRhK4, p=0·0004). Interpretation As far as we know, our study presents the first quantitative data for tropism, replication kinetics, and cell damage of SARS-CoV-2. These data provide novel insights into the lower incidence of diarrhoea, decreased disease severity, and reduced mortality in patients with COVID-19, with respect to the pathogenesis and high transmissibility of SARS-CoV-2 compared with SARS-CoV. Funding May Tam Mak Mei Yin, The Shaw Foundation Hong Kong, Richard Yu and Carol Yu, Michael Seak-Kan Tong, Respiratory Viral Research Foundation, Hui Ming, Hui Hoy and Chow Sin Lan Charity Fund, Chan Yin Chuen Memorial Charitable Foundation, Marina Man-Wai Lee, The Hong Kong Hainan Commercial Association South China Microbiology Research Fund, The Jessie & George Ho Charitable Foundation, Perfect Shape Medical, The Consultancy Service for Enhancing Laboratory Surveillance of Emerging Infectious Diseases and Research Capability on Antimicrobial Resistance for the Department of Health of the Hong Kong Special Administrative Region Government, The Theme-Based Research Scheme of the Research Grants Council, Sanming Project of Medicine in Shenzhen, and The High Level-Hospital Program, Health Commission of Guangdong Province, China.

negative: Pains and Gains from China's Experiences with Emerging Epidemics: From SARS to H7N9 Over the recent decades, China experienced several emerging virus outbreaks including those caused by the severe acute respiratory syndrome- (SARS-) coronavirus (Cov), H5N1 virus, and H7N9 virus. The SARS tragedy revealed faults in China's infectious disease prevention system, propelling the Chinese government to enact reforms that enabled better combating of the subsequent H1N1 and H7N9 avian flu epidemics. The system is buttressed by three fundamental, mutually reinforcing components: (1) enduring government administration reforms, including legislation establishing a unified public health emergency management system; (2) prioritized funding for biotechnology and biomedicine industrialization, especially in the areas of pathogen identification, drug production, and the development of vaccines and diagnostics; and (3) increasing investment for public health and establishment of a rapid-response infectious diseases prevention and control system. China is now using its hard-gained experience to support the fight against Ebola in Africa and the Middle East Respiratory Syndrome in its own country.

negative: COVID-19 and Tuberculosis: A mathematical model based forecasting in Delhi, India BACKGROUND: There is emerging evidence that patients with Latent Tuberculosis Infection(LTBI) and Tuberculosis(TB) disease have an increased risk of the SARS-CoV-2 infection and predisposition towards developing severe COVID-19 pneumonia. In this study we attempted to estimate the number of TB patients infected with SARS-CoV-2 and have severe disease during the COVID-19 epidemic in Delhi, India. METHODS: Susceptible-Exposed-Infectious-Recovered (SEIR) model was used to estimate the number of COVID-19 cases in Delhi. Assuming the prevalence of TB in Delhi to be 0.55%, 53% of SARS-CoV2 infected TB cases to present with severe disease we estimated the number of SARS-CoV2 infected TB cases and the number of severe patients. The modelling used estimated R(0) for two scenarios, without any intervention and with public health interventions. RESULTS: We observed that the peak of SARS-CoV-2-TB co-infected patients would occur on the 94th day in absence of public health interventions and on 138(th) day in presence of interventions. There could be 20,880 SARS-CoV-2 infected TB cases on peak day of epidemic when interventions are implemented and 27,968 cases in the absence of intervention. Among them, there could be 14,823 patients with severe disease when no interventions are implemented and 11,066 patients with severe disease in the presence of intervention. CONCLUSION: The importance of primary prevention measures needs to be emphasized especially in TB patients. The TB treatment centres and hospitals needs to be prepared for early diagnosis and management of severe COVID-19 in TB patients.

negative: Sequential informed pooling approach to detect SARS-CoV2 infection The alarming spread of the pandemic coronavirus disease 2019 (COVID-19) caused by the SARS-CoV-2 virus is requiring several measures to reduce the risk of contagion. Every successful strategy in controlling SARS-CoV2 infection depends on the timely viral diagnosis which should include asymptomatic carriers. Consequently, strategies to increase the throughput for clinical laboratories to conduct large-scale diagnostic testing are urgently needed. Here we support the hypothesis that standard diagnostic protocol for SARS-CoV-2 virus could be conveniently applied to pooled samples obtained from different subjects. We suggest that a two-step sequential pooling procedure could identify positive subjects, ensuring at the same time significant benefits of costs and time. Simulation data are used to assess the efficiency, in terms of number of required tests, both for random assignment of the subjects to the pools and for situations when epidemiological and clinical data are used to create an "informed" version of the pooling. Different scenarios are examined in the simulations to measure the effect of different pool sizes and different values for the virus frequency. Our results allow to customize the pooling strategy according to the specific characteristics of the cohort to be tested.

negative: Time to realise the true potential of Ayurveda against COVID-19

negative: Recombinant porcine rotavirus VP4 and VP4-LTB expressed in Lactobacillus casei induced mucosal and systemic antibody responses in mice BACKGROUND: Porcine rotavirus infection is a significant cause of morbidity and mortality in the swine industry necessitating the development of effective vaccines for the prevention of infection. Immune responses associated with protection are primarily mucosal in nature and induction of mucosal immunity is important for preventing porcine rotavirus infection. RESULTS: Lactobacillus casei expressing the major protective antigen VP4 of porcine rotavirus (pPG612.1-VP4) or VP4-LTB (heat-labile toxin B subunit from Echerichia coli) (pPG612.1-VP4-LTB) fusion protein was used to immunize mice orally. The expression of recombinant pPG612.1-VP4 and pPG612.1-VP4-LTB was confirmed by SDS-PAGE and Western blot analysis and surface-displayed expression on L. casei was verified by immunofluorescence. Mice orally immunized with recombinant protein-expressing L. casei produced high levels of serum immunoglobulin G (IgG) and mucosal IgA. The IgA titters from mice immunized with pPG612.1-VP4-LTB were higher than titters from pPG612.1-VP4-immunized mice. The induced antibodies demonstrated neutralizing effects on RV infection. CONCLUSION: These results demonstrated that VP4 administered in the context of an L. casei expression system is an effective method for stimulating mucosal immunity and that LTB served to further stimulate mucosal immunity suggesting that this strategy can be adapted for use in pigs.

negative: COVID-19, SARS and MERS: are they closely related? Abstract Background The 2019 novel coronavirus (SARS-CoV-2) is a new human coronavirus which is spreading with epidemic features in China and other Asian countries; cases have also been reported worldwide. This novel coronavirus disease (COVID-19) is associated with a respiratory illness that may lead to severe pneumonia and acute respiratory distress syndrome (ARDS). Although related to the severe acute respiratory syndrome (SARS) and the Middle East respiratory syndrome (MERS), COVID-19 shows some peculiar pathogenetic, epidemiological and clinical features which to date are not completely understood. Aims To provide a review of the differences in pathogenesis, epidemiology and clinical features of COVID-19, SARS and MERS. Sources The most recent literature in the English language regarding COVID-19 has been reviewed, and extracted data have been compared with the current scientific evidence about SARS and MERS epidemics. Content COVID-19 seems not to be very different from SARS regarding its clinical features. However, it has a fatality rate of 2.3%, lower than that of SARS (9.5%) and much lower than that of MERS (34.4%). The possibility cannot be excluded that because of the less severe clinical picture of COVID-19 it can spread in the community more easily than MERS and SARS. The actual basic reproductive number (R0) of COVID-19 (2.0–2.5) is still controversial. It is probably slightly higher than the R0 of SARS (1.7–1.9) and higher than that of MERS (<1). A gastrointestinal route of transmission for SARS-CoV-2, which has been assumed for SARS-CoV and MERS-CoV, cannot be ruled out and needs further investigation. Implications There is still much more to know about COVID-19, especially as concerns mortality and its capacity to spread on a pandemic level. Nonetheless, all of the lessons we learned in the past from the SARS and MERS epidemics are the best cultural weapons with which to face this new global threat.

negative: Why is chest CT important for early diagnosis of COVID-19? Prevalence matters SARS-CoV-2 viral infection is a global pandemic disease (COVID-19). Reaching a swift, reliable diagnosis of COVID-19 in the emergency departments is imperative to direct patients to proper care and to prevent disease dissemination. COVID-19 diagnosis is based on the identification of viral RNA through RT-PCR from oral-nasopharyngeal swabs, which however presents suboptimal sensitivity and may require several hours in overstressed laboratories. These drawbacks have called for an additional, complementary first line approach. CT is the gold standard method for the detection of interstitial pneumonia, a hallmark feature of COVID-19, often present in the asymptomatic stage of the disease. Here, we show that CT scan presents a sensitivity of 95.48% (std.err=0.35%), vastly outperforming RT-PCR. Additionally, as diagnostic accuracy is influenced by disease prevalence, we argue that predictive values provide a more precise measure of CT reliability in the current pandemics. We generated a model showing that CT scan is endowed with a high negative predictive value (> 90%) and positive predictive value (69 - 84%), for the range of prevalence seen in countries with rampant dissemination. We conclude that CT is an expedite and reliable diagnostic tool to support first line triage of suspect COVID-19 patients in areas where the diffusion of the virus is widespread.

negative: Induction of anti-viral immune responses by immunization with recombinant-DNA encoded avian coronavirus nucleocapsid protein Abstract Immune responses to the infectious bronchitis virus (IBV) nucleocapsid protein were studied using a recombinant-DNA expression product. In mice, a lymphocyte proliferative response and a delayed-type hypersensitivity reaction to IBV were induced upon immunization with this nucleocapsid protein. Next, we studied the role of the expressed nucleocapsid protein in induction of a protective immune response to IBV in chickens. Chickens were primed with nucleocapsid protein and subsequently boosted with inactivated IBV, strain M41. Proliferative responses of blood mononuclear cells corresponded with increased mean haemagglutination inhibition and virus neutralization titres. Finally, an increased tracheal protection against challenge with live IBV was observed. These results indicate that infectious bronchitis virus nucleocapsid protein is a relevant target for immune recognition in both the mouse and the chicken.

negative: Coronavirus Disease 2019 (COVID-19) and pregnancy: what obstetricians need to know Coronavirus disease 2019 is an emerging disease with a rapid increase in cases and deaths since its first identification in Wuhan, China, in December 2019. Limited data are available about coronavirus disease 2019 during pregnancy; however, information on illnesses associated with other highly pathogenic coronaviruses (ie, severe acute respiratory syndrome and the Middle East respiratory syndrome) might provide insights into coronavirus disease 2019’s effects during pregnancy. Coronaviruses cause illness ranging in severity from the common cold to severe respiratory illness and death. Currently the primary epidemiologic risk factors for coronavirus disease 2019 include travel from mainland China (especially Hubei Province) or close contact with infected individuals within 14 days of symptom onset. Data suggest an incubation period of ∼5 days (range, 2–14 days). Average age of hospitalized patients has been 49–56 years, with a third to half with an underlying illness. Children have been rarely reported. Men were more frequent among hospitalized cases (54–73%). Frequent manifestations include fever, cough, myalgia, headache, and diarrhea. Abnormal testing includes abnormalities on chest radiographic imaging, lymphopenia, leukopenia, and thrombocytopenia. Initial reports suggest that acute respiratory distress syndrome develops in 17–29% of hospitalized patients. Overall case fatality rate appears to be ∼1%; however, early data may overestimate this rate. In 2 reports describing 18 pregnancies with coronavirus disease 2019, all were infected in the third trimester, and clinical findings were similar to those in nonpregnant adults. Fetal distress and preterm delivery were seen in some cases. All but 2 pregnancies were cesarean deliveries and no evidence of in utero transmission was seen. Data on severe acute respiratory syndrome and Middle East respiratory syndrome in pregnancy are sparse. For severe acute respiratory syndrome, the largest series of 12 pregnancies had a case-fatality rate of 25%. Complications included acute respiratory distress syndrome in 4, disseminated intravascular coagulopathy in 3, renal failure in 3, secondary bacterial pneumonia in 2, and sepsis in 2 patients. Mechanical ventilation was 3 times more likely among pregnant compared with nonpregnant women. Among 7 first-trimester infections, 4 ended in spontaneous abortion. Four of 5 women with severe acute respiratory syndrome after 24 weeks’ gestation delivered preterm. For Middle East respiratory syndrome, there were 13 case reports in pregnant women, of which 2 were asymptomatic, identified as part of a contact investigation; 3 patients (23%) died. Two pregnancies ended in fetal demise and 2 were born preterm. No evidence of in utero transmission was seen in severe acute respiratory syndrome or Middle East respiratory syndrome. Currently no coronavirus-specific treatments have been approved by the US Food and Drug Administration. Because coronavirus disease 2019 might increase the risk for pregnancy complications, management should optimally be in a health care facility with close maternal and fetal monitoring. Principles of management of coronavirus disease 2019 in pregnancy include early isolation, aggressive infection control procedures, oxygen therapy, avoidance of fluid overload, consideration of empiric antibiotics (secondary to bacterial infection risk), laboratory testing for the virus and coinfection, fetal and uterine contraction monitoring, early mechanical ventilation for progressive respiratory failure, individualized delivery planning, and a team-based approach with multispecialty consultations. Information on coronavirus disease 2019 is increasing rapidly. Clinicians should continue to follow the Centers for Disease Control and Prevention website to stay up to date with the latest information (https://www.cdc.gov/coronavirus/2019-nCoV/hcp/index.html).

negative: Animal models and antibody assays for evaluating candidate SARS vaccines: Summary of a technical meeting 25–26 August 2005, London, UK Severe acute respiratory syndrome (SARS) emerged in the Guangdong province of China in late 2002 and spread to 29 countries. By the end of the outbreak in July 2003, the CDC and WHO reported 8437 cases with a 9.6% case fatality rate. The disease was caused by a previously unrecognized coronavirus, SARS-CoV. Drawing on experience with animal coronavirus vaccines, several vaccine candidates have been developed and evaluated in pre-clinical trials. Available data suggest that vaccines should be based on the the 180 kDa viral spike protein, S, the only significant neutralization antigen capable of inducing protective immune responses in animals. In the absence of clinical cases of SARS, candidate vaccines should be evaluated for efficacy in animal models, and although it is uncertain whether the United States Food and Drug Administration's “animal rule” would apply to licensure of a SARS vaccine, it is important to develop standardized animal models and immunological assays in preparation for this eventuality. This report summarizes the recommendations from a WHO Technical Meeting on Animal Models and Antibody Assays for Evaluating Candidate SARS Vaccines held on 25–26 August 2005 in South Mimms, UK, provides guidance on the use of animal models, and outlines the steps to develop standard reagents and assays for immunological evaluation of candidate SARS vaccines.

negative: Evolution and containment of transmissible recombinant vector vaccines Transmissible vaccines offer a revolutionary approach for controlling infectious disease and may provide one of the few feasible methods for eliminating pathogens from inaccessible wildlife populations. Current efforts to develop transmissible vaccines use recombinant vector technology whereby pathogen antigens are engineered to be expressed from innocuous infectious viral vectors. The resulting vaccines can transmit from host to host, amplifying the number of vaccine‐protected individuals beyond those initially vaccinated directly through parenteral inoculation. One main engineering challenge is the potential for natural selection to favor vaccine mutants that eliminate or reduce expression of antigenic inserts, resulting in immunogenic decay of the vaccine over time. Here, we study a mathematical model of vector mutation whereby continuous elimination of the antigenic insert results in reversion of the vaccine back into the insert‐free vector. We use this model to quantify the maximum allowable rate of reversion that can be tolerated for a transmissible vaccine to maintain a critical threshold level of immunogenicity against a target pathogen. Our results demonstrate that even for transmissible vaccines where reversion is frequent, performance will often substantially exceed that of conventional, directly administered vaccines. Further, our results demonstrate the feasibility of designing transmissible vaccines that yield desired levels of immunogenicity, yet degrade at a rate sufficient for persistence of the recombinant vaccine within the environment to be minimized.

negative: A reverse transcription loop-mediated isothermal amplification method for rapid detection of bovine viral diarrhea virus Abstract A reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay was developed and optimized to detect bovine viral diarrhea viral (BVDV) RNA. The RT-LAMP assay is highly sensitive and able to detect 4.67×100 copies of BVDV RNA. Additionally, the RT-LAMP method is capable of detecting both genotypes of BVDV. No cross-reaction with other bovine viruses was observed. The ability of RT-LAMP to detect BVDV RNA from bovine fecal swabs was also evaluated. Of the 88 fecal swabs, 38 were found to be positive by RT-LAMP assay, whereas 39 were positive by real-time RT-PCR. Taken together, the BVDV specific RT-LAMP method is highly specific and sensitive and can be used as a rapid and direct diagnostic assay for testing clinical samples.

negative: Using network science to propose strategies for effectively dealing with pandemics: The COVID-19 example The global spread of Coronavirus Disease 2019 (COVID-19) is overwhelming many health-care systems. As a result, epidemiological models are being used to inform policy on how to effectively deal with this pandemic. We note that the majority of existing models do not take into account differences in the amount of interactions between individuals (i.e. the underlying human interaction network). Using network science we demonstrate how this network of interactions can be used to predict the spread of the virus and to inform policy on the most successful mitigation and suppression strategies. Although applicable to disease modelling in general, our results emphasize how network science can improve the predictive power of current COVID-19 epidemiological models. We provide commented source code for all our analyses so that they can easily be integrated into current and future epidemiological models.

negative: Suppressed humoral immunity is associated with dengue nonstructural protein NS1-elicited anti-death receptor antibody fractions in mice Dengue virus (DENV) infections may cause life-threatening dengue hemorrhagic fever (DHF). Suppressed protective immunity was shown in these patients. Although several hypotheses have been formulated, the mechanism of DENV-induced immunosuppression remains unclear. Previously, we found that cross-reactive antibodies against tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) receptor 1 (death receptor 4 [DR4]) were elicited in DHF patients, and that anti-DR4 autoantibody fractions were elicited by nonstructural protein 1 (NS1) immunizations in experimental mice. In this study, we found that anti-DR4 antibodies could suppress B lymphocyte function in vitro and in vivo. Treatment with the anti-DR4 immunoglobulin (Ig) induced caspase-dependent cell death in immortalized B lymphocyte Raji cells in vitro. Anti-DR4 Igs elicited by NS1 and DR4 immunizations markedly suppressed mouse spleen transitional T2 B (IgM(+)IgD(+)), bone marrow pre-pro-B (B220(+)CD43(+)), pre-B (B220(+)CD43(−)), and mature B cell (B220(+)IgD(+)) subsets in mice. Furthermore, functional analysis revealed that the pre-elicitation of anti-NS1 and anti-DR4 Ig titers suppressed subsequently neutralizing antibody production by immunization with DENV envelop protein. Our data suggest that the elicitation of anti-DR4 titers through DENV NS1 immunization plays a suppressive role in humoral immunity in mice.

negative: Use of Hemagglutinin Stem Probes Demonstrate Prevalence of Broadly Reactive Group 1 Influenza Antibodies in Human Sera A better understanding of the seroprevalence and specificity of influenza HA stem-directed broadly neutralizing antibodies (bNAbs) in the human population could significantly inform influenza vaccine design efforts. Here, we utilized probes comprising headless, HA stabilized stem (SS) to determine the prevalence, binding and neutralization breadth of antibodies directed to HA stem-epitope in a cross-sectional analysis of the general population. Five group-1 HA SS probes, representing five subtypes, were chosen for this analyses. Eighty-four percent of samples analyzed had specific reactivity to at least one probe, with approximately 60% of the samples reactive to H1 probes, and up to 45% reactive to each of the non-circulating subtypes. Thirty percent of analyzed sera had cross-reactivity to at least four of five probes and this reactivity could be blocked by competing with F10 bNAb. Binding cross-reactivity in sera samples significantly correlated with frequency of H1(+)H5(+) cross-reactive B cells. Interestingly, only 33% of the cross-reactive sera neutralized both H1N1 and H5N1 pseudoviruses. Cross-reactive and neutralizing antibodies were more prevalent in individuals >50 years of age. Our data demonstrate the need to use multiple HA-stem probes to assess for broadly reactive antibodies. Further, a universal vaccine could be designed to boost pre-existing B-cells expressing stem-directed bNAbs.

negative: Cytokine release syndrome in severe COVID-19. Lessons from arthritis and cell therapy in cancer patients point to therapy for severe disease.

negative: Distinct Patterns of B-Cell Activation and Priming by Natural Influenza Virus Infection Versus Inactivated Influenza Vaccination Background. The human B-cell response to natural influenza virus infection has not been extensively investigated at the polyclonal level. Methods. The overall B-cell response of patients acutely infected with the 2009 pandemic influenza A(H1N1)pdm09 virus (A[H1N1]pdm09) was analyzed by determining the reactivity of plasmablast-derived polyclonal antibodies (PPAbs) to influenza proteins. Recipients of inactivated influenza vaccine containing the same A(H1N1)pdm09 strain were studied for comparison. Results. During acute infection, robust plasmablast responses to the infecting virus were detected, characterized by a greater PPAb reactivity to the conserved influenza virus nuclear protein and to heterovariant and heterosubtypic hemagglutinins, in comparison to responses to the inactivated A(H1N1)pdm09 vaccine. In A(H1N1)pdm09 vaccinees, the presence of baseline serum neutralizing antibodies against A(H1N1)pdm09, suggesting previous exposure to natural A(H1N1)pdm09 infection, did not affect the plasmablast response to vaccination, whereas repeated immunization with inactivated A(H1N1)pdm09 vaccine resulted in significantly reduced vaccine-specific and cross-reactive PPAb responses. Conclusions. Natural A(H1N1)pdm09 infection and inactivated A(H1N1)pdm09 vaccination result in very distinct patterns of B-cell activation and priming. These differences are likely to be associated with differences in protective immunity, especially cross-protection against heterovariant and heterosubtypic influenza virus strains.

negative: Susceptible supply limits the role of climate in the COVID-19 pandemic Preliminary evidence suggests that climate may modulate the transmission of SARS-CoV-2. Yet it remains unclear whether seasonal and geographic variations in climate can substantially alter the pandemic trajectory, given high susceptibility is a core driver. Here, we use a climate-dependent epidemic model to simulate the SARS-CoV-2 pandemic probing different scenarios of climate-dependence based on known coronavirus biology. We find that while variations in humidity may be important for endemic infections, during the pandemic stage of an emerging pathogen such as SARS-CoV-2 climate may drive only modest changes to pandemic size and duration. Our results suggest that, in the absence of effective control measures, significant cases in the coming months are likely to occur in more humid (warmer) climates, irrespective of the climate-dependence of transmission and that summer temperatures will not substantially limit pandemic growth.

negative: Urbanization and Infectious Diseases: General Principles, Historical Perspectives, and Contemporary Challenges In 2009, a major demographic line was crossed: for the first time in history, the majority of the world population lived in cities rather than in towns and countryside (Fig. 4.1). This shift has been occurring over the past 100 years, with the most rapid rate of urban growth occurring over in the latter half of the twentieth century. Urban centers in the more developed regions of the world (i.e., North America, Australia, New Zealand, and Europe) experienced earlier growth in the 1920s–1950s, and since then, the rapid rate of urban growth has been concentrated in the cities and towns of developing nations [1].

negative: Protocol for a multicentre study of nosocomial SARS-CoV2 transmission The NOSO-COR Project Introduction: The newly identified SARS-CoV2 can cause serious acute respiratory infections such as pneumonia with a mortality rate of approximately 2% to 4%. In the current context of high incidence rates of SARS-CoV2 in the community, a significant increase in the rate of nosocomial transmission is expected. The risk of nosocomial transmission could even be higher in low-income countries that have fragile healthcare systems. This protocol is intended to study and document suspected or confirmed cases of nosocomial SARS-CoV2 infection, the clinical spectrum and the determinants (risk factors/protective) at participating hospitals. Methods and analysis: This will be an international multicentre prospective, observational, hospital-based study in adults and children. It will include volunteer patients, care givers and healthcare professionals in France and hospitals affiliated with the GABRIEL network. Demographic and clinical data will be collected using case-report forms designed especially for the purpose of the project. A nasopharyngeal swab will be collected and tested for SARS-CoV2 by RT-PCR. Characteristics of the study participants, the proportion of confirmed nosocomial SARS-CoV2 infections relative to all patients with syndromes suggestive of 2019-nCoV infection will be analysed. Appropriate multivariate modelling will be used to identify the determinants associated with nosocomial onset. Ethics and dissemination: This study was approved by the clinical research and committee of Ile de France V on March 8, 2020. Registration details: The trial was registered in ClinicalTrials (NCT04290780).