The Epidemiology of Tuberculosis in Physicians

Abstract
The incidence of tuberculosis in physicians was determined by mailed questionnaire. Since 1950 tuberculosis infection preceding entry into medical school has decreased by 73%; at the same time, infection after beginning medical school decreased by 78%. Tuberculin conversion rates among recent graduates exceeded 1% per year, and age-specific infection rates among physicians were at least twice the US average. Tuberculosis developed in nearly one in ten physicians infected after medical school entry; in two thirds, disease preceded or coincided with recognized tuberculin positivity. No tuberculosis occurred in physicians who used isoniazid chemoprophylaxis, but two thirds of tuberculin-negative physicians did not have annual skin tests, 56% of known recent converters used no chemoprophylaxis, and 25% of those initiating isoniazid prophylaxis did not complete a 12-month course. The Bacillus Calmette-Guérin vaccine recipients had 80% less tuberculosis than unimmunized physicians infected after beginning medical school. (JAMA241:33-38, 1979)