Setting: A South African suburb with a high tuberculosis incidence (> 800/100,000).
Objective: To determine the prevalence of tuberculosis infection and disease in children less than 5 years of age who were in close household contact with adults with pulmonary tuberculosis.
Design: Prospective clinical study.
Subjects: Children under 5 years of age (of whom > 98% had been BCG vaccinated in the neonatal period) in household contact with an adult with tuberculosis.
Investigation: Clinical investigation, Mantoux skin testing, chest radiography, gastric aspirate culture for Mycobacterium tuberculosis.
Results: Of 155 children younger than 5 years in contact with 80 index cases (83% smear positive), 14% were infected and 34% diseased. Children aged under 2 years had more severe disease (endobronchial tuberculosis and bronchial compression). Of 154 household members aged over 5 years who were assessed, 17 had culture proven pulmonary tuberculosis (13 smear positive) and a further 16 were placed an antituberculosis treatment on the basis of radiological evidence.
Conclusion: In a high tuberculosis incidence area evaluation of and chemoprophylaxis for childhood contacts of adults with pulmonary tuberculosis is a rewarding procedure. The detection of culture and smear positive pulmonary tuberculosis amongst adolescent and adult household contacts emphasizes the role of contact tracing in the detection of infectious cases of pulmonary tuberculosis and the prevention of the spread of tuberculosis.