Tuberculosis, HIV disease, and directly observed therapy.

Directly observed therapy (DOT) to enable completion of antituberculous therapy works. DOT is largely responsible for the recent improvement in tuberculosis case rates in New York City. Despite this favorable trend, the factors of significant HIV disease rates and of multidrug resistant forms of tuberculosis bacteria in the population are of grave concern. Therefore, in addition to DOT other means of preventing tuberculosis spread should be encouraged. These include directly observed preventive therapy (DOPT) programs, use of masks, improved ventilation in crowded settings such as homeless shelters, and ultraviolet light germicidal irradiation of upper room air in such locations.