Secular trends of grossly underreported snakebite burden in India, 2009-2018: analysis of data from India's National Health Profile.

Abstract

India's National Health Profile (NHP) documents snakebite cases and deaths based on hospital-based reports, hence underrepresenting the actual burden. We describe secular trends of NHP data using population denominators for 2009-2018. We abstracted the data on snakebite cases and deaths and calculated incidence and case fatality rate (CFR) by gender and by states using population denominators. We estimated the change in incidence and CFR over time by using a Poisson regression model. We computed the incidence rate ratio (IRR) and 95% confidence interval (CI) using Stata 14.0. The incidence of snakebites ranged from 89 to 141 per million population and without any specific pattern during 2009-2018 as per NHP reports. The incidence increased by 3% per year (IRR 1.03 [95% CI 0.99 to 1.07]). The incidence was higher among males (range 97-163) than females (range 71-115) and there was no difference in trends by gender (IRR 1.07 [95% CI 0.37 to 3.12]). The CFR was 5-13 deaths per 1000 cases, with an annual decline of 12% (IRR 0.88 [95% CI 0.85 to 0.92]). The CFR did not differ by gender (male 5-12, female 6-13; IRR 0.48 [95% CI 0.20 to 1.17]). India's NHP snakebite data, representing an underestimate of the actual burden, suggests no specific secular trend and points to areas documenting consistent and significant burden.