during the outbreak , a standardized case report form was filled out for each patient admitted to uhpap who had clinical symptoms consistent with chikungunya and a positive chikv rt - pcr test result on a blood sample . the information recorded included demographics , preexisting comorbidities , which were summarized by using the charlson index ( 3 ) and mccabe classification ( 4 ) , and clinical manifestations described by organ system ( e.g. , cardio - circulatory , cerebral , respiratory , renal , and hepatic ) . standard definitions were used for organ system failures and severe sepsis and septic shock ( 5 ) . the following laboratory parameters were retrieved from the patient s record in the hospital s electronic medical system : whole and differential leukocyte and platelet counts ; corpuscular hemoglobin ; and c - reactive protein , serum creatinine , alanine aminotransferase , aspartate aminotransferase , creatine kinase , and lactate dehydrogenase levels . for each parameter , 2 values were considered , the first value recorded within the first 24 hours of admission and the most abnormal value observed from hospital day 2 through day 7 . after hospital discharge or death , each case of chikv infection was categorized as one of the following : 1 ) a common form , in which only fever or arthralgia occurred ; 2 ) an atypical form , in which > 1 organ system was involved ; and 3 ) a severe form , in which the patient had > 1 organ system failure or had been admitted to the intensive care unit . of the 110 nonpregnant adults hospitalized with chikungunya who had a positive chikv rt - pcr test result , 34 had a common form , 34 had an atypical form , and 42 had a severe form . therefore , we compared the characteristics of the 48 patients with severe forms with those of the 68 patients with nonsevere forms ( i.e. , common and atypical forms ) by selected demographic , clinical , laboratory , and outcome characteristics . patients with severe forms were not older and did not have more comorbidities than patients with nonsevere forms . at hospital admission , the rates of classical signs of chikungunya , such as fever and peripheral arthralgia , were similar in both groups . patients with severe forms had significantly less occurrence of headache but increased occurrence of acute cardiac failure ; they also had occurrence of organ dysfunction significantly more often than did patients with nonsevere forms ( table 1 ) . as for laboratory abnormalities , patients with severe forms had significantly higher whole leukocyte counts , polymorphonuclear cell counts , and serum lactate dehydrogenase levels at baseline and within the first week after admission ( table 1 ) . p value denotes the comparisons between the 42 patients with severe forms and the 68 patients with nonsevere forms , based on nonparametrical tests . among the 42 patients who had a severe form of the disease , 25 patients had illness consistent with the case definition for severe sepsis and had no other identified cause for this syndrome but chikv , according to blood and urine cultures , which had been performed systematically in all these patients . overall , the background characteristics of these 25 patients were not significantly different from those of the other 85 patients ( tables 1 , 2 ) . at admission to hospital , these 25 patients had significantly higher occurrence of cardiac , respiratory , and renal manifestations and had significantly higher leukocyte counts and levels of serum lactate dehydrogenase , aspartate aminotransferase , and creatinine , which are clinical and laboratory indicators of sepsis , than did patients without severe sepsis or septic shock ( table 2 ) . in addition , their mortality rate was significantly higher than that in patients without severe sepsis or septic shock ( 48% vs. 3% , p<0.001 ) . p value denotes the comparisons between the 25 patients with severe sepsis or septic shock and the 85 patients with no severe sepsis or septic shock , based on nonparametrical tests . the following case report describes one of the 25 patients with severe sepsis or septic shock . the patient died of septic shock , which had no other identified cause but chikv infection . an 85-year - old man with no prior medical history except treated hypertension developed an acute influenza - like syndrome . on day 2 of illness , a common form of chikv infection was diagnosed by his general practitioner , and the patient received treatment for his symptoms . on day 4 , he was referred to a hospital emergency department because of persistent high - grade fever . his hemodynamic condition was normal , and the diagnosis of chikv infection was maintained ; however , because of elevated levels of whole leukocytes ( total 40 g / l ) , polymorphonuclear neutrophils ( 37.5 g / l ) , and serum c - reactive protein ( 170 mg / l ) , blood and urine samples were collected for culture , and treatment with ceftriaxone was started . approximately 12 hours after admission to the emergency department , the patient experienced onset of septic shock and died within 4 hours . a chikv - positive rt - pcr test result was the only positive diagnostic test result obtained for this patient . although chikungunya usually has a mild course , severe life - threatening complications can develop during the acute phase of the disease ( 6,7 ) . previous studies indicate that the disease can be complicated by severe multiple organ failure and lead to death ( 8,9 ) . very recently , the first cases of severe sepsis and septic shock that could be attributed to chikv infection were reported ( 10,11 ) . in some of these cases , the replication of viruses , especially of the family herpetoviridae , has been shown to occur frequently during the course of septic shock syndromes of bacterial origin , not only as a stress - induced reactivation but also as a superinfection causing additional morbidity ( 12 ) . by contrast , cases of virus - triggered septic shock have been reported only rarely ( 13 ) , although a recent cross - sectional study of septic shock syndromes in a pediatric population suggested that viruses might be the only etiology in up to 10% of cases ( 14 ) . on the other hand , genuine acute severe viral infections might be complicated with a bacterial septic shock , which is well known to occur in cases of influenza but has also been reported in cases of arboviral diseases , such as dengue fever ( 15 ) . in our study , none of the 25 patients who had a positive chikv rt - pcr test result and a severe sepsis or septic shock syndrome early in the course of chikungunya had another organism identified as a potential cause of sepsis . this finding strongly suggests that chikv can , in rare cases , cause severe sepsis and septic shock syndromes , an observation that had not been reported until very recently . additional studies are needed to identify any background characteristics that might be associated with the onset of severe sepsis or septic shock .
during a 2014 outbreak , 450 patients with confirmed chikungunya virus infection were admitted to the university hospital of pointe -  - pitre , guadeloupe . of these , 
 110 were nonpregnant adults ; 42 had severe disease , and of those , 25 had severe sepsis or septic shock and 12 died . 
 severe sepsis may be a rare complication of chikungunya virus infection .