Infectivity of patients with pulmonary tuberculosis in inner city homes.

Abstract

Drs. Richard Riley and Allan Moodie have provided valuable information on the Infectivity of Patients with Pulmonary Tuberculosis in Inner City Homes in the REVIEW (1974, 110, 810) . I would hope that one of the modifications of the continuing study will be the inclusion of a skin test at approximately 10 weeks in order to document more exactly the time of infection. The large interval between the 6th and the 20th week following the first test might have been too long. Another possibility should be considered to ex· plain the absence of late conversions in contacts of patients treated at home. The observation is also consistent with the hypothesis that all of the suscePtible contacts had already been infected by the time the index case was identified, leaving only those with heightened natm·al resistance at risk of subsequent infection. I believe that both factors, loss of infectivity after initiation of chemotherapy and previous infection of the more susceptible contacts, were operative.