摘要：Tuberculosis (TB) is a major public health problem in developing countries. BCG vaccination is a preventive intervention and part of a Universal Childhood Immunization Programme in India. Doubts have been raised regarding the efficacy of the BCG vaccines, and studies around the world have reported an efficacy ranging from 0% to 90%. We have carried out a case-control study to estimate the ageand site-specific protective effect of BCG against childhood TB in Pondicherry, South India. One-hundred cases of TB in children were identified from paediatric inpatient and outpatient departments. Four ageand sex-matched hospital controls were selected randomly from the Department of Paediatrics, the Paediatric Surgery and the Trauma Department. The BCG vaccination status was ascertained by BCG scar and from the children's clinic cards. For children up to five years of age, the protective effect of BCG was higher against TB meningitis (97%, 95% Cl 78%, 99%) than against pulmonary TB (64% CI 20%, 80%). The protective effect was lower against both types of TB in children aged five years and older. We conclude that BCG provides a high degree of protection against both TB meningitis and pulmonary TB in children up to the age of five years. J Epidemiol, 1995; 5 : 43-48.
