Estimated mortality rate and leading causes of death among individuals with chikungunya in 2016 and 2017 in Brazil

Abstract

Introduction: In 2014, the first cases of autochthonous chikungunya (CHIK) were recorded in Brazil. Lethality associated with this disease is underestimated. Thus, this study aimed to analyze the causes of death among individuals with CHIK in Brazil. Methods: A descriptive observational study was conducted on individuals with CHIK who died within 6 months from symptom onset. Data pairing between the Information System for Notifiable Diseases and the Mortality Information System was performed. Deaths were classified according to case confirmation criterion, mention of CHIK in the death certificates (DCs), and disease phase. The lethality rate per 1,000 cases was corrected for underreporting and was estimated according to region, sex, age, years of education, race/color, and cause groups. Results: We identified 3,135 deaths (mention of CHIK in the DCs, 764 [24.4%]). In 17.6% of these cases, CHIK was the underlying cause. Most deaths occurred in the acute (38.1%) and post-acute (29.6%) phases. The corrected LR (5.7; x1,000) was 6.8 times higher than that obtained from the Information System for Notifiable Diseases (0.8). The highest corrected LRs were estimated for among individuals living in the Northeast region (6.2), men (7.4), those with low years of education and those aged <1 year (8.6), 65-79 years (20.7), and ≥80 years (75.4). Conclusions: The LR of CHIK estimates based on information system linkage help to reveal the relevance of this disease as the direct cause or as a cause associated with serious or fatal events, provide timely interventions, and increase the knowledge about this disease.

Cardiomyopathy and Death Following Chikungunya Infection: An Increasingly Common Outcome

“…Death caused directly by CHIKV infection is not commonly reported; however, there are reports of excess deaths in countries in which a CHIKV epidemics have occurred [ 20 , 21 , 55 , 87 , 88 ] ( Table 2 and Table 4 ). In regard to CHIKV infections with altered cardiac status, 11 deaths were reported out of 23 individual case reports (48%) ( Table 4 ).…”

“…There is limited or inaccurate reporting in many of the areas where CHIKV infections have surfaced, frequently due to lack of infrastructure [ 20 , 21 ]. It is possible that there are additional cardiac symptoms of CHIKV infection that are unknown, or additional patients that did not seek medical care due to access issues.…”

“…Further, the finding of viral myocarditis is concerning due to its connection with other cardiomyopathies such as dilated cardiomyopathy, which can also result in death [ 18 , 19 ]. While most CHIKV infections result in mild symptoms, myocarditis does not always present overtly, which could lead to a future high burden on healthcare systems where outbreaks have occurred [ 18 ]; a number of these countries have underdeveloped infrastructure; thus, this burden could be overwhelming [ 20 , 21 ]. Since there is no distinct course of action for CHIKV infection, nor a vaccine, CHIKV infection should be concerning to clinicians [ 22 ].…”

Epidemiological burden of Chikungunya fever in Brazil, 2016 and 2017

“…Deaths that mention CHIKF (ICD A92.0) as the underlying cause in the SIM were included in this study. Further details on the organisation of the database have been provided in a previous study that estimated the mortality rate and leading causes of death among CHIKF patients in Brazil in 2016 and 2017 [11].…”

“…Total deaths from CHIKF a SIM [9] Total deaths from CHIKF a SIM [9] Life expectancy at birth in years 88.87 b GBD [11] 88.87 b GBD [11] Cases Total cases a SINAN [8] Total cases a × expected proportion for the chronic phase (50%)…”