BCG vaccination of children against leprosy: fourteen-year findings of the trial in Burma.

The value of BCG vaccination in preventing leprosy among children was studied in an area of high leprosy endemicity in Burma through a controlled trial; one group of 13 066 children received BCG and another group of 13 176 served as controls. The overall protective effect of BCG, which was only about 20% over the 14-year period, was found to vary with the batch of vaccine, as well as age, sex, and contact status of the children. BCG protection was found to be independent of the initial tuberculin status of the children. The protective effect of BCG against the lepromatous type of leprosy could not be measured because of the low incidence. Protection was observed throughout the fourteen years of the study except for the first year. The results are compared with those of three other major BCG trials in leprosy. The trial has shown that BCG provides only a very modest level of protection and that BCG vaccination is not likely to be an important solution for leprosy control.