Unusually aggressive transmission of tuberculosis in a factory.

A case of pulmonary tuberculosis in a factory worker was studied to identify infected contacts and to gauge the degree of transmission. Initial findings suggested far more extensive transmission than anticipated, and the study was expanded. Of all factory workers tested, 33% were infected with the tubercule bacillus in spite of massive air volume-to-contact ratio. Deliberate stagnation of the air to prevent occupational exposure to lead and asbestos was believed to be a contributing variable.