Infectivity of sputum-positive tuberculous patients on chemotherapy.

Abstract

A retrospective study was undertaken to assess infectivity for household contacts of tuberculous patients briefly hospitalized in a private general hospital and discharged receiving ambulatory chemotherapy while sputum still contained tubercle bacilli. Eighty-six patients (Group A) were discharged for supervised home therapy while culture positive (52 were positive by smear), and 69 patients (Group B) were negative by both smear and culture at discharge. The median hospital stay was less than 6 weeks, and the median time for culture conversion to negative after discharge for Group A was 41 days. Risk of infection for 284 Group A contacts and for 216 Group B contacts was assessed by skin testing performed before discharge of the index case, or 3 months after the index case became culture negative, or both. Brief hospitalization required skin test data to be analyzed according to the total number of reactors among each group of contacts. When induration of more than either 5 or 9 mm were considered positive...