RESEARCH ARTICLE Follow-Up of Chronic Coughers Improves Tuberculosis Case Finding: Results from a Community-Based Cohort Study in Southern

Background Untreated smear-positive tuberculosis (TB) patients are the primary source of infection; however, a large number of TB cases have not been identified and are untreated in many sub-Saharan African countries, including Ethiopia. This study determined whether or not a community-based follow-up of chronic coughers improves detection of TB cases and the risk factors for death among such cases. Methods We conducted a census in six rural communities in Sidama, southern Ethiopia. Based on in-terview and sputum investigation, we identified 724 TB smear-negative chronic coughers, and did a cohort study of these chronic coughers and 1448 neighbourhood controls. For both chronic coughers and neighbourhood controls, we conducted a TB screening interview and performed sputum microscopy, as required, at 4, 7 and 10 months. Between Septem-ber 2011 and June 2012, we followed chronic coughers and neighbourhood controls for 588 and 1,204 person-years of observation, respectively