Vaccination against leprosy at Ben San Leprosy Centre, Ho Chi Minh City, Vietnam

Three vaccines, BCG alone, BCG + 10(7) killed Mycobacterium vaccae and 10(8 ) killed M. vaccue alone, were studied in children living in close contact with leprosy. In the year before vaccination, 14/446 (3.1%) children had de veloped leprosy. Among those who were not vaccinated, 9/74 (12.2%) develope d the disease in the first 4 years of the study and 5/65 (7.7%) developed t he disease in the second 4 years. In comparison with this, among those vacc inated, 20/343 (5.8%) developed leprosy in the first 4 years and 5/323 (1.5 %) developed leprosy in the second 4 years. This represents 52.5% protectio n in the first 4 years and 80.5% in the second 4 years. There were no signi ficant differences in protection afforded by each of the three vaccines but the success of the killed preparation of M. vaccae is an important finding . (C) 2001 Elsevier Science Ltd. All rights reserved.