Prior BCG vaccination improves survival of Gambian patients treated for pulmonary tuberculosis

The protection provided by BCG against pulmonary tuberculosis ranges from n il to over 90%. While BCG protects against the more serious forms of tuberc ulosis, it is not known whether or nor it protects patients with pulmonary tuberculosis from death. In a study designed to look at the effects of immu notherapy with hi. vaccae as an adjunct to chemotherapy in 285 adult Gambia n patients treated for proven pulmonary tuberculosis, we examined the assoc iation between the presence or absence of a BCG scar and mortality The data showed that subjects who had a BCG scar were significantly younger than th ose who did not, and were less likely to have nutritional oedema. During th e course of treatment, none of the 85 patients who had a BCG scar died comp ared to 35 of 200 patients (17.5%) who did not (P < 0.001). In these Gambia n patients with pulmonary tuberculosis, prior vaccination with BCG may have provided substantial protection against death. However, there is the possi bility that this finding is the result of confounding by other factors or h as arisen from bias. Researchers with similar data need to investigate this question as this association, if true, could have major implications for B CG vaccination.