Effect of BCG vaccination on leprosy in Kenya.

In 1 9G2 Dr. C. M. Ross had started a pilot leprosy control proj ect in Samia district and he intended to study the effect of BCG vaccination on leprosy . The work of this devoted and conscientious leprologist was broken off by his death in 1 964. The data of his surveys mentioned in this article are derived from his original notes . In 1 962 Ross examined 1 7 7 children in schools at Buholo, Central Nyanza . He found 28 children with leprosy, a prevalence of 1 6 % . All patients were non-lepromatous . In 1 964 the schoolchildren in this area were vacci nated with BCG. In 1 966 we have carried out a re-survey in the same schools . In 320 children examined only one tuberculoid patient was found, a prevalence of 0 . 3 % . I n 1 962 Ross also examined 6 0 children in schools at Sio Port . He found 8 non-lepromatous patients , a prevalence of 1 3 . 3 % . In 1 964 BCG was given to the children. In 1 966 we re-surveyed the schools. In 276 children examined only one tuberculoid patient was found, a prevalence of 0 .4%. This patient was one of the few children who were absent when the schoolchildren were vaccinated . He developed leprosy in 1 965. Of the 37 patients registered by Dr. Ross in 1 962, 1 5 children were re-examined in 1 966 . In these children the lesions had completely resolved, in many of them without treatment . Obviously the patients seen by Dr. Ross, and classified as indeterminate or tuberculoid, had a very mild self-healing type of leprosy.