Comprehensive tuberculosis screening and preventive treatment in schools and congregate settings of India (2017–2024): a prospective study

Background: Existing Tuberculosis (TB) elimination strategies show limited impact, with suboptimal uptake of tuberculosis preventive treatment (TPT) and increasing TB incidence after the COVID-19 pandemic. Real-world evidence on reduction of tuberculosis in high-burden communities is needed to inform future TB elimination strategies. Methods: Since 2017, a comprehensive TB screening and TPT program known as Zero TB in Kids (ZTBK) was implemented in congregate settings of Tibetan communities in India. TB disease, TB infection (TBI), tuberculin skin test (TST) conversion, and TPT uptake were measured periodically. Findings: Schoolchildren and adults in 63 institutes (n = 20,068; 67,637 person-years) were screened. TPT was given to 3847 participants. TB incidence decreased 83% between 2017 [576 (95% CI: 455-718)/100,000] and 2024 [97 (47-179)/100,000]. TB infection (TBI) prevalence decreased 32% between 2017 [22% (95% CI: 21-23%)] and 2024 [15.5% (14-17%)]. TB incidence (640/100,000) and TBI prevalence (28%) were higher in the institutes that were never screened before under ZTBK. Among participants who did not receive TPT, TB disease prevalence decreased 84% between 2017 [910 (95% CI: 675-1204)/100,000] and 2024 [147 (48-343)/100,000], indicating a herd benefit. After one round of TB screening and TPT, between 2018 and 2019, TST conversion decreased 59% for children and 47% for adolescents. Risk of TBI was greater for males (aPR: 1.23; 95% CI: 1.16-1.30). TB risk was 82% lower for schoolchildren receiving TPT. Participants with seizure disorder [aPR: 0.31 (95% CI: 0.15-0.65)] and hepatitis B [0.71 (0.6-0.84)] were less likely to receive TPT. Interpretation: Significant reduction of TB transmission and burden can be achieved using the existing tools of TB control. Surveillance of TBI and TPT must be widely adopted for schools and congregate settings with high TB burden. Funding: National Institutes of Health-National Institute of Allergy and Infectious Diseases (NIAID) (K01-AI148583), STOP TB Partnership (STBP/TBREACH/GSA/W7-7692), NIAID-Johns Hopkins Center for AIDS Research (90100777), Foundations, and Philanthropy.