Case-Fatality Ratio of Enteric Fever: Estimates From Multitiered Surveillance in India

Background. The case-fatality ratio (CFR) for enteric fever is essential for estimating disease burden and calibrating measures that balance the likely health gains from interventions against social and economic costs. Methods. We aimed to estimate the CFR for enteric fever using multiple data sources within the National Surveillance System for Enteric Fever in India. This surveillance (2017-2020) was established as a multitiered surveillance system including community cohorts (tier 1), facility-based (tier 2), and tertiary care surveillance (tier 3) for estimating the burden of enteric fever in India. The CFR was calculated after accounting for healthcare-seeking behavior for enteric fever and deaths occurring outside the hospital. Results. A total of 1236 hospitalized patients with blood culture-confirmed enteric fever were enrolled, of which 9 fatal cases were identified, for an estimated hospitalized CFR of 0.73% (95% confidence interval [CI], .33%-1.38%). After adjusting for severity; healthcare-seeking behavior, and deaths occurring out-of-hospital, the CFR was estimated to be 0.16% (95% CI, .07%-.29%) for all enteric fevers. Conclusions. Our estimates of the CFR are relatively lower than previously estimated, accounting for care-seeking behavior and deaths outside the hospital.