A vaccine is a preparation of attenuated or killed pathogen that is administered for prevention, betterment, or treatment of a contagious disease Vaccines are one of the most important developments of the modern world and save an estimated 2-3 million lives every year by preventing and controlling infectious disease outbreaks The first person to make a scientific attempt to control infectious disease using vaccination was Edward Jenner in 1796, enabling the eradication of smallpox The first laboratory vaccine using an attenuated pathogen was developed in 1879 by Louis Pasteur against chicken cholera). Today, there are many types of vaccines available for many infectious diseases of different species. Different types of vaccine fall under distinct categories and can be selected depending on different considerations, including the risk factors of the recipient. The categories are Live-attenuated vaccines, inactive or dead vaccines, conjugate or subunit vaccines, viral vector vaccines, and toxoids
Types of vaccines used in cats
The popular vaccine types used in veterinary practice are modified live vaccines (MLV), and inactive or killed vaccines, although other types are on the rise. MLVs contain attenuated pathogens that trigger a response from the immune system. MLVs generally give a higher-quality immune response compared to inactive vaccines, however, they are not appropriate for use in cats that have compromised immune systems. The attenuated virus may still be too strong and there is a possibility of reversion to virulence. Inactive vaccines contain pathogens that have been killed to remove disease-producing capacity. Inactivated viruses tend to produce a weaker immune response than MLV's, necessitating the addition of adjuvants or making booster injections a requirement for adequate protection
Core vaccines for cats.
A consensus has started to emerge amongst the three international panels providing guidelines on feline vaccination protocols. The American Association of Feline Practitioners (AAFP) Feline Vaccine Advisory Panel, the European Advisory Board on Cat Diseases (ABCD), and the World Small Animal Association Vaccine Guidelines Group (WSAVA VGG) have agreed on the three core vaccinations that make up the core combination. These are panleukopenia virus (FPV), also known as feline parvovirus, herpesvirus (FHV-1), and calicivirus (FCV). It is agreed that rabies virus should be added to the core combination where it is endemic or a legal requirement. Booster vaccinations are recommended at intervals of more than one year in line with evidence of the duration of protection from these vaccines
FPV Class Core Core Core
Primary Vaccination of kittens Begin from as early as 6 weeks, then every 3-4 weeks until 16 weeks of age Begin at 6-8 weeks of age, then every 2-4 weeks until 16 weeks of age or older Begin at 8-9 weeks with a second 3-4 weeks (minimum 12w). Consider a final dose at 16-20 weeks of age
Booster Vaccinations Consider at 6 months rather than one year after the primary course, then no more frequently than every 3 years 6 months or one year after the primary course, then no more frequently than every 3 years One year after the primary course, then no more frequently than every 3 years unless special conditions apply
FHV-1 Class Core Core Core
Primary Vaccination of kittens Begin as early as 6 weeks, then every 3-4 weeks until 16 weeks of age Begin at 6-8 weeks of age, then every 2-4 weeks until 16 weeks of age or older Begin at around 9 weeks with a second 2-4 weeks later
Booster Vaccinations Consider at 6 months rather than one year after the primary course, then no more frequently than every 3 years 6 months or one year after the primary course, then every 3 years for low-risk cats. Annual vaccinations for at-risk cats. Annually, especially in high-risk situations
FCV Class Core Core Core
Primary Vaccination of kittens
Begin as early as 6 weeks, then every 3-4 weeks until 16 weeks of age Begin at 6-8 weeks of age, than ever y 2-4 weeks until 16 weeks of age or older Begin at around 9 weeks with a second 2-4 weeks later (not earlier than 12w)
Consider a third dose at 16w in high-risk situations
Booster Vaccinations Consider at 6 months rather than one year after the primary course, then no more frequently than every 3 years 6 months or one year after the primary course, then every 3 years for low-risk cats. Annual vaccinations for at-risk cats. Boost annually
Introduction to the Covid-19 pandemic
Coronavirus disease 2019 (COVID-19) was first detected in December 2019. The World Health Organization (WHO) declared the outbreak as a pandemic on March 11, 2020 A series of lockdowns were implemented in the UK in an attempt to prevent the spread of Covid-19. On March 26, 2020, the first lockdown measures legally came into force, and further lockdowns were put in place throughout 2020 and 2021
22.9% of adults surveyed by the Office for National Statistics said the pandemic was affecting their household finances. The greatest concern was reduced income (72.9%). 31.9% of adults were using savings to cover their living costs and 22.1% reported they struggled to pay bills at all)
Impact of covid-19 on the veterinary profession
Businesses have been adversely affected by lockdown measures. During the pandemic, veterinary practices were able to operate in line with the UK government's advice to businesses. In March 2020, veterinary professionals were limited to urgent and emergency services only. Practices then transitioned to and from providing emergency care, to a more normal range of services, keeping in line with the changing guidance The Royal College of Veterinary Surgeons advised veterinary professionals should stop elective and preventive care to avoid non-essential travel and protect human health by reducing the use of anesthetic gases, oxygen, and other resources required for frontline human healthcare in the battle against Covid-19 This has caused interruption to the routine vaccination of companion animals. In cases where cats have had a starter course and a booster, they have sufficient immunity to protect them for 3 years. Cats that had the starter course but are late for the first booster only have an extra 3-month period to have the first booster. If these periods expire, the cat is not protected against the core combination diseases and the vaccination course needs to be restarted. These are known as the ‘off-license’ periods
The Investigation
Aim:
The aim of this investigation is to explore the effect of the Covid-19 pandemic on the routine vaccination of domestic felines in the UK.
Objectives:
To achieve this aim I will collect data from cat owners in the UK regarding vaccine uptake during the pandemic. I will create a survey that will be distributed online in various cat-focused groups and analyze the results.
Hypothesis:
The Covid-19 pandemic has harmed the routine vaccination of domestic felines in the UK.
A lack of availability of preventative care has left cats at risk of contracting FPV, FHV-1, and FCP.
Materials and method
Materials needed for this investigation were a survey, access to online cat-focused groups, and appropriate data analysis software. The survey was created in Microsoft Forms due to its ability to facilitate different question pathways based on individual answers. Different pathways were needed to determine which cats posed an exposure risk based on the off-license period of vaccines, and the subsequent protection from them. The target demographic for the survey was cat owners in the UK. Due to Covid-19 restrictions, the survey needed to be distributed online. Many online cat groups were identified. Contact was made with the admins of these groups to obtain permission to post the survey link, and to collect information from its members. Once permission was obtained, the link to the survey was posted, requesting responses from UK cat owners only. The responses were downloaded into an excel spreadsheet and analyzed. No personal or identifiable information was collected from participants of the survey,
Results
Of the 103 survey responses, 71 cats were already in their homes pre-pandemic. Of these 71 cats, 59 cats would normally be vaccinated. However, during the pandemic, 27 (45.8%) of these 59 cats did not receive their booster and a further 13 (22%) received their boosters late. Of the 27 not receiving a booster, 5 were due to cost, 9 due to shielding, and 12 due to restrictions placed on veterinary practices. During the pandemic, the rate of those not being vaccinated or being vaccinated late rose from 14% (10) to over 70% (50).
Of the 103 survey responses, 32 cats were adopted during the pandemic. 3 cats did not have an initial vaccine. 2 of these were due to restrictions placed on veterinary practices, and the remaining case was due to shielding. A further 19 initial vaccinations were delayed, meaning that 22 out of the 32 cats (69%) were put at risk due to the pandemic. This same cohort of 32 cats had 19 boosters delayed, 15 of which had already had their initial vaccinations delayed.
Of the 103 cats, 83 (80.5%) were either outdoors or spent time outdoors. These cats, therefore, signal a greater risk for infection and the spread of viruses. Of these 83 cats, 34 (41%) did not receive their vaccine or booster, with a further 28 (33.7%) having their vaccine or boosters delayed. In cats adopted during the pandemic, the greater issue was delayed vaccine boosters (18) as opposed to those missing vaccines (2). For cats in established homes, the opposite was true, with missed boosters (32) being more prevalent than delayed (10) ones.
Of the 103 surveys returned, 5 cats were not vaccinated as the owner did not want to vaccinate them. 2 of these are indoor cats
Discussion
Discussion of Results
There were 103 survey respondents from around the UK. The majority of responses came from Southern England, from counties in and around London. These results cannot be generalized to reflect the whole of the UK due to local lockdowns that occurred throughout 2020 and 2021. Local lockdowns were imposed on specific areas of the UK to control the spread of the coronavirus pandemic to avoid a country-wide lockdown. This meant some areas were affected for longer than others, and some areas of the country had tighter restrictions
31% of owners that responded to the survey said they adopted their cat during the Covid-19 pandemic. It is known that a high number of animals were adopted during this time. In the week of 16 March to 22 March 2020, 69 cats were adopted from Battersea. That is a 138% increase from the number in the same week of 2019 when 29 cats were adopted from the shelter.
83% of owners declared that before the Covid-19 pandemic, their cat would usually receive their vaccine booster. This is a high percentage compared to the 2020 PDSA Paw report, which surveyed 3875 cat owners. The PDSA report states that 64% of cats were receiving regular boosters This discrepancy is likely caused by the small sample size obtained in the survey. The survey shows Covid-19 lockdown restrictions caused the percentage of cats being vaccinated to fall to 26%. This supports hypothesis 1, the Covid-19 pandemic has hurt the routine vaccination of domestic felines in the UK. As these are adult cats that have received previous boosters, it is likely that some of them still had some immunity, however, cats that had reached the end of the 3-year interval would have been put at risk of catching FPV, FHV-1 or FCP, and would have needed to restart their vaccine course. Two doses 2â4 weeks apart are generally recommended for a restart for all three vaccines, but a single dose of MLV vaccine is considered protective against FPV
27 cats were put at risk due to the secondary effects of Covid-19. This includes financial strain caused by unemployment, mandatory shielding for certain demographics, and restrictions placed on veterinary practices. The NHS reports that there are 3.8 million shielded patients in England and a further 130,000 in Wales. As the human population continues with the Covid-19 vaccine rollout, the number of people shielding will decrease, however, the financial strain is likely to continue, potentially leading to more unvaccinated cats.
Of the 32 cats that were adopted during the pandemic, 3 cats did not have an initial vaccine due to secondary effects of the covid-19 pandemic. 2 of these cats were affected by restrictions placed on veterinary practices, while the remaining cat could not attend a veterinary practice due to mandatory shielding required of the owner. A further 19 initial vaccinations were delayed, meaning that 22 out of the 32 cats (69%) were put at risk of infection due to the Covid-19 pandemic. This same cohort of 32 cats had 19 boosters delayed, 15 of which had already had their initial vaccinations delayed. This included 9 cats whose boosters were more than three months late. These cats fell outside of the vaccination off-license period and therefore needed to restart their vaccination course This supports hypothesis 2, the lack of availability of preventative care has left cats at risk of contracting FPV, FHV-1, and FCP. For cats that required a restart course, some organizations like RVC were able to offer a vaccine amnesty, whereby the owners were charged for a booster instead of the cost of a restart course This is a reasonable offer for those that were affected by lockdown restrictions placed on the veterinary profession, however, more assistance will be needed for those that could not vaccinate their cat due to financial hardship caused by Covid-19.
3.1% of cats owned within the pandemic and 12.7% of cats owned before the pandemic had their vaccination schedule interrupted by their owner's need to shield. This number will inevitably drop as cat owners are vaccinated against Covid-19, however, some may still need to shield themselves until the vaccine roll-out is complete. This may call for more mobile veterinary services to provide veterinary care for those that cannot attend a veterinary practice.
83 of the 103 cats included in the survey had access to the outdoors, (80.5%). This is slightly higher than the percentage given by the PDSA Paw report, which amounted to 74% This number could be higher due to the margin of error created by the smaller sample size, or it could have increased due to the rise of pet ownership during the pandemic Of these 83 cats that had access to the outdoors, 74.7% were a potential risk for contracting and spreading infectious diseases due to lack of, or delayed vaccination.
21.4% of respondents stated that they do not vaccinate their cats as advised by the veterinary profession. This number is lower than the percentage obtained from the PDSA Paw Report, which amounted to 36%. The PDSA report state that 20% of unvaccinated cats are due to refusal, while another 20% are due to financial hardship. These numbers are closer to the results of this survey, where 23% of unvaccinated cats are due to refusal, and 23% are due to financial hardship not caused by Covid-19. 90% of these unvaccinated cats had access to the outdoors, increasing the risk of contracting and spreading infectious disease to feral and stray cats in the area, and the cats identified that usually would have received their booster vaccines, but could not due to Covid-19.
Improvements
For a greater understanding of how Covid-19 has affected the routine vaccination of domestic felines in the UK, surveys should be undertaken in all counties and compared, taking into consideration the specific local lockdown measures imposed on those areas. A larger sample size is needed to reduce the margin of error, and a confirmation of the core combination vaccines should be included in the survey, to avoid confusion with other non-core vaccines available.
Future surveys should focus on breaches of the off-license period for initial and booster vaccinations. This will help determine the level of risk to cats that have experienced a delay or lack of vaccination due to Covid-19 lockdown restrictions. Questions should also be asked of feral stray cat populations, and cats that reside in multi-cat households. The survey did not distinguish between cats allowed outdoors in cat-proofed gardens, and cats allowed to free-roam. Future surveys should pose these questions to more accurately assess the risk of unvaccinated cats contracting and spreading disease.
The reliability of the data from the survey relies on the honesty of the respondents, that may feel inclined to answer in a way that makes them look more favorable. Although harder to obtain, more accurate reports on vaccine uptake could be obtained from veterinary practices.
Conclusion
The Covid-19 pandemic has hurt the routine vaccination of domestic felines in the UK, leaving domestic cats at higher risk of contracting and spreading FPV, FHV-1, and FCP. As the pandemic is ongoing, the consequences of the secondary effects of Covid-19 for feline populations are yet to be realized. Veterinary professionals should be encouraged to use a surveillance network such as SAVSNET to identify a rise in cases of FPV, FHV-1, and FCV. Cat owners should be educated on the importance of core-combination vaccines.