Influence of segregation to tuberculous patients for one year on the attack rate of tuberculosis in a 2-year period in close family contacts in South India.

The authors present a second report from the Tuberculosis Chemotherapy Centre, Madras, on the incidence of tuberculosis in close family contacts of tuberculous patients. The patients initially received a year's chemotherapy either at home or in sanatorium in a controlled comparison of the merits of domiciliary as opposed to institutional treatment. The first report presented data relating to the prevalence and the attack rate of tuberculosis among the contacts during the first year of treatment of the index cases; this second report presents the attack rate for the 2-year period since the start of treatment for the index cases. During the second year all the index cases were managed at home, those with active disease, and half of those with quiescent disease, at the end of the first year receiving further chemotherapy. The findings of the 2-year study confirm those of the earlier study-namely, that the incidence of tuberculosis in the contacts of patients originally treated at home was no greater than that in the contacts of patients originally treated in sanatorium and that the major risk to the contacts resulted from exposure to the patient before diagnosis. As in the earlier report, the question of instituting chemoprophylaxis for the young contacts of tuberculous patients is discussed. The authors consider that close family contacts living in over-crowded, urban conditions in the developing countries are valuable groups for chemoprophylactic investigations.