Mycobacterium leprae
The history of leprosy was traced to its origins by an international team of 22 geneticists using comparative genomics of the worldwide distribution of "Mycobacterium leprae". Monot "et al." (2005) determined that leprosy originated in East Africa or the Near East and traveled with humans along their migration routes, including those of trade in goods and slaves. The four strains of "M. leprae" are based in specific geographic regions where each predominantly occurs: