Controlled trial of active tuberculosis case finding in a Brazilian favela

A large, impoverished squatters' settlement (favela), Rio de Janeiro, Brazil.

To assess the community impact of active case finding for tuberculosis (TB) compared to an enhanced case-finding strategy.

A pair-matched, cluster-randomized trial comparing household symptom screening and spot sputum collection (Arm 1) vs. distribution of an educational pamphlet (Arm 2) was performed in a large Brazilian favela. We compared TB case-notification rates, time from symptom onset to treatment start and treatment completion proportions between arms. Fourteen neighborhoods (estimated population 58,587) were pair-matched by prior TB case rates and randomly allocated to one of two interventions. TB was diagnosed using acid-fast bacilli smears. New TB cases were interviewed and clinic records were reviewed.

A total of 193 TB cases were identified in the 14 study neighborhoods (incidence proportion 329 per 100,000 population). The case identification rate in Arm 1 was 934/100,000 person-years (py) vs. 604/100,000 py in Arm 2 (RR 1.55, 95%CI 1.10-1.99). No significant differences were found in time from cough onset to treatment start or proportion completing treatment.

A door-to-door case-finding campaign was more effective (while ongoing) at detecting prevalent cases and influencing people to come for care than leafleting, but no differences were seen in time to treatment start or treatment completion.