TURN-TB (Trace Ultra Result iNsight in TB screening) is a case-control study that aims to compare baseline Xpert® MTB/RIF Ultra (“Ultra”) assay "trace-positive" individuals to positive and negative controls and includes a longitudinal cohort study with TB-negative controls. Partly in coordination with the STOMP-TB study, the study conducts community-based TB screening as well as recruitment from local facilities, and enrolls participants with trace-positive results for an extensive baseline clinical and laboratory evaluation. Those who are not diagnosed with TB at baseline are closely followed for up to 2 years to evaluate the incidence of TB, treat it promptly if it develops, and observe any changes that occur over time in symptoms, microbiological results, imaging findings, and host responses. The study’s primary aims are to:  

1. Characterize baseline evidence for current or past TB disease and infection among individuals with Ultra-trace-positive sputum.

2. Longitudinally evaluate the incidence of TB and the dynamics of molecular, imaging, and immunological findings among individuals with trace-positive Ultra but no active TB at study entry.

3. Quantitatively and qualitatively explore the implications of trace-positive results and associated patient trajectories for active TB case finding strategies.