In the late 1970’s the inoculation of Mycobacterium leprae in patients resulted in a positive immunological response. Thereafter, assays with cultured Mycobacterium leprae were performed, as the same bacteria isolated from human lesions were identified in Armadillos. This led to a successful culture of the bacteria and the final production of an effective specific immunotherapy (vaccine) to treat Leprosy using the isolated bacteria plus BCG.