Epidemiology of Primary Tuberculosis in an Industrial School

Abstract

FOR many years it was generally accepted that primary tuberculosis developed almost exclusively among persons who had prolonged and intimate contact with infectious sources. The mechanism of infection was poorly understood, but it was believed that the organisms spread through the air in particles, the inhalation of which resulted in the development of a pulmonary lesion. Little was known about the precise nature of this process until Wells, Ratcliffe and Crumb¹ demonstrated that the size of the inhaled particle was important. Rabbits inhaling 2 or 3 bovine tubercle bacilli dispersed as single units contracted more pulmonary tuberculosis than when inhaling . . .