Culturally relevant settings for TB transmission in an African city with endemic TB

SUMMARY BACKGROUND TB persists because Mycobacterium tuberculosis ( M. tb ) is transmitted through unknown community contact networks. This transmission occurs in culturally relevant settings as infectious cases go about their daily lives. We performed a prospective cohort study in Kampala, Uganda, to estimate incident TB infection (TBI) and relate it to time spent in a broad array of settings. METHODS In a prospective cohort study of 1,275 adult residents without TBI, we measured cumulative incidence of infection at 1 year using the tuberculin skin test. We measured time spent in community settings using a validated questionnaire and related settings to incident infection using Poisson regression analysis. RESULTS The settings visited by participants varied by weekday and sex. Participants spent most of their time at home or work regardless of the weekday. New infection with M. tb was associated with worship centres, schools, and homes of relatives or friends, though these effects were modified by day of the week, categorised as weekday or weekend. CONCLUSION Social settings, such as schools or worship centres, may be appropriate sites to screen for TB. Community-based interventions to control TB should consider age, sex, and day of the week to reduce gaps in coverage.