NIAID-funded scientists at the National Hansen’s Disease Program (NHDP) laboratories are also using genomic knowledge of M. leprae to examine leprosy transmission. From earlier epidemiological studies, NIAID-funded scientists at NHDP knew that M. leprae had been found among wild armadillos in Texas and Louisiana, suggesting that human contact with infected armadillos might lead to infection. Recently, the research team, led by by Richard W. Truman, Ph.D., compared the gene sequences of M. leprae samples taken from humans and infected wild armadillos and found that 64 percent of human samples had a particular genotype that had never been seen before. What’s more, 85 percent of armadillo samples shared that same genotype.
These results showed that the two strains were related and that wild armadillos were a likely source of some human infections. But more importantly, it established leprosy as a zoonosis: an infectious disease that can be transmitted back and forth between animals and humans.