Effectiveness of bacillus Calmette Guerin (BCG) vaccination against extra-pulmonary tuberculosis: a case-control study.

A hospital-based pair-matched case-control study was carried out at Govt. Medical College Hospital, Nagpur, to estimate the effectiveness of BCG vaccination against extra-pulmonary tuberculosis. The study included 125 cases of extra-pulmonary tuberculosis in the age group of 0-30 years and 375 tuberculosis free control. Each case was pair matched against three separate controls for age, sex and socioeconomic status. The protective effectiveness and prevented fraction were higher for the subjects in the age group of 0-10 years, males and subjects from middle and upper strata of socio-economic class but it was statistically nonsignificant. The overall vaccine effectiveness and prevented fraction was estimated to be 80.86 (72.68-86.60) and 53.20 (41.97-63.73) per cent respectively. Results of this study thus indicated that BCG vaccination was highly effective against extra-pulmonary tuberculosis and played a significant role in its prevention in this population.

Effectiveness of mass neonatal BCG vaccination in the prevention of pulmonary tuberculosis: a case-control study in Nagpur, India.

SETTING: Government Medical College, Nagpur, India, a tertiary care hospital. OBJECTIVE: To estimate the effectiveness of mass neonatal BCG vaccination in the prevention of pulmonary tuberculosis in Nagpur, India. DESIGN: A hospital-based pair-matched case-control study with a case of 1:3, including 144 cases of pulmonary tuberculosis and 432 controls. RESULTS: The overall vaccine effectiveness estimated in the present study was 60% (95% Confidence Interval [CI] 43%-72%). The protective effect was more in males in the age group 21-30 years. The prevented fraction was 39% (95% CI 24%-52%). CONCLUSION: The moderate effectiveness demonstrated in this study needs to be substantiated for other forms of tuberculosis by undertaking community-based case-control studies, before attempting to justify the use of mass neonatal BCG vaccination strategy as a part of the national programme.