Can Household Contact Investigation Reduce Tuberculosis?

Abstract There is a large burden of tuberculosis (TB) globally, and infection often spreads among household contacts of patients with TB. This large, cluster-randomized trial was the first to robustly demonstrate the benefits of active case finding in TB transmission. Districts in Vietnam were randomized into intervention and control arms. In the intervention districts, contacts of TB patients were actively screened for TB. The contacts of patients in the control districts were not screened, but were given educational materials. The authors found that the relative risk of screening positive for TB was 2.6 (95% CI 2.0 to 3.3) in intervention districts. The number of persons who would need to be screened to gain one additional registered case of TB was 74.6 (95% CI 64.2 to 89.2). This study demonstrates the effectiveness of active case finding for TB in high-burden countries.