Childhood tuberculosis in North Carolina: a study of the opportunities for intervention in the transmission of tuberculosis to children.

New cases of tuberculosis in children continue to appear. A retrospective review of the medical records of a representative sample of such cases occurring from 1977 through 1981 was conducted to gain an understanding of why this preventable disease continues to occur in North Carolina children. Three per cent of cases were detected by routine screening; 17 per cent were diagnosed after the child's symptomatic presentation; and 80 per cent after contact screening. However, 14 per cent of cases detected by contact screening developed disease while receiving isoniazid prophylaxis for a positive tuberculin test; and 19 per cent of cases detected by contact screening developed disease while under surveillance, but not receiving isoniazid prophylaxis, as tuberculin negative contacts of known infectious cases. Adherence to accepted recommendations for prophylaxis should reduce the childhood tuberculosis case rate.