Burden of typhoid fever and antimicrobial resistance in India (2023): a modelling study

Abstract

Background India is one of the countries with a high typhoid fever burden. In 2022, the National Technical Advisory Group on Immunisation recommended including the typhoid conjugate vaccine (TCV) in the Universal Immunisation Programme. In this study, we aimed to estimate the 2023 burden of typhoid fever and its antimicrobial resistance (AMR) to inform targeted vaccine introduction strategies. Methods We used a decision tree model to estimate typhoid cases, hospitalisations, complications, and deaths. Incidence and clinical parameters were derived from a multicentre Indian study, with state-wise AMR prevalence from a systematic review. Two co-primary and four alternative scenarios were presented to validate the robustness of the findings. Findings We estimated 4.9 million (95% UI: 4.4–5.6) typhoid cases and 7850 (4300–14,900) deaths in India in 2023. Of 730,000 (534,000–970,000) hospitalisations, 600,000 (435,000–799,000; 82%) were attributable to fluoroquinolone-resistant. Under primary scenario A, children <5 years accounted for 321,000 (235,000–427,000; 44.0%) hospitalisations and 2600 (1300–4800; 34.0%) deaths. Under primary scenario B, 5–9 years of age accounted for 265,000 (135,000–278,000; 36.0%) hospitalisations and 2900 (1500–5300; 36.0%) deaths. Delhi, Maharashtra, and Karnataka together accounted for 29% of the national burden and had the highest rates of fluoroquinolone-resistant cases and deaths among the ten highest-burden states. Deaths linked to fluoroquinolone-resistance, multidrug resistance, third-generation cephalosporins, and azithromycin resistance were 4700 (1800–10,200), 122 (45–294), 183 (69–431), and 183 (68–432), respectively. Interpretation Fluoroquinolone-resistance drives a large share of typhoid-related hospitalisations and deaths, especially in children under five and in high-burden states of India. Targeted TCV introduction, with broader age coverage among children, would maximise impact. Funding WISE programme ; Vaccine Impact Modelling Consortium ; Japan Agency for Medical Research and Development