Knowledge of tuberculosis among drug users. Relationship to return rates for tuberculosis screening at a syringe exchange.

Tuberculosis is an important health issue among drug users. We sought to evaluate active drug users' (DUs) knowledge of tuberculosis (TB) and to assess the relationship between TB knowledge and attitudes and tuberculin skin test (TST) return rates at a syringe exchange program. DUs were recruited at a syringe exchange program in New York City, were interviewed and offered TSTs, and received $15.00 upon returning for TST reading. The questionnaire evaluated knowledge of TB transmission, prevention, and treatment. From March 13, 1995 to January 31, 1996, 610 of 650 (94%) of DUs approached agreed to participate. Of these, 80% had previous TSTs within the past 2 years and 20% were known to be HIV infected. Almost all knew that TB is contagious and more than two thirds knew that TB is treatable and that TB preventive therapy existed. However, fewer than half knew that HIV-related TB could be treated, 30% thought TB could be treated without a medical doctor, and the majority (70%) thought a reactive TST implied infectivity. The rate of return for TST reading was 93%. In multivariate analysis, those who knew that HIV-related TB was curable were more likely to return for TST reading (odds ratio 2.0; 95% confidence interval 1.04 to 3.95; p = .03). The high acceptance and return rates suggest that TB services can be incorporated into syringe exchange programs. However, several important gaps in TB knowledge existed in this population at high risk of TB, which may impact on adherence and which support the need for TB education for drug users.