Programmatic implications of a sub-national TB prevalence survey in India.

Abstract

Subnational TB estimates are crucial for making informed decisions to tailor TB control activities to local TB epidemiology.A cross-sectional survey was conducted among 143,005 individuals in Tamil Nadu, India. Participants were screened for symptoms and underwent chest X-ray (CXR). Participants with symptoms of TB and/or abnormal CXR were tested for TB using Xpert, smear, and liquid culture.The prevalence of microbiologically confirmed pulmonary TB (MCPTB) was 212 (95% CI 184-239) per 100,000 population. The prevalence-to-notification ratio (P:N) in the state was 2.05 (95% CI 1.8-2.29). Low body mass index and diabetes together had a population attributable fraction of 54.15 (95% CI 45.68-61.97). Approximately 39% of the TB cases were asymptomatic and were identified only by CXR screening. In the general population, only 26.9% sought care at a health facility among those with symptoms suggestive of TB.The programme needs to prioritise screening with CXR to potentially detect cases earlier and curtail the transmission and upscale molecular tests in the selected population to increase the yield of case finding. Innovative health education strategies must be devised to address health-seeking behaviour..