Infected Armadillos and Humans Often Share Same Strain of Leprosy
We all pretty much knew that armadillos are a source of leprosy. (Right, we all pretty much knew that?) In fact, a 2005 review by Louisiana State’s Richard W. Truman, PhD, reminds us that wild armadillos were recognized as early as 1975 to harbor Mycobacterium leprae, the causative agent,* and that the probable sources of the pathogen for armadillos were European and African immigrants to the New World some 400-500 years ago. But leprosy also appears to be a disease that has kept on giving, or more accurately circulating…between the 2 species.
This conclusion is supported by a recent genome-sequencing study, led by Truman and the results of which are published in this week’s issue of the NEJM. The data show that infected humans and armadillos in disease-endemic areas of the Americas (like Louisiana and Venezuela), in fact, often harbor the same M. leprae strain—suggesting that leprosy is a bona-fide zoonosis.
But how North Americans have acquired and are acquiring the leprosy pathogen from armadillos has not been well-defined. Truman tells the NYT that the contact is probably not casual, given the persnickety nature of the bug.** He advises that “people should be discouraged from consuming armadillo flesh or handling it,” a relatively common practice in areas of, for example, Brazil—a country that contributes one half of all leprosy cases in the Americas.
* The reason being that armadillos have a naturally low core body temperature, which fosters the growth of M. laprae.
** Because M. leprae cannot be cultivated in a Petri-dish-type culture, armadillos have historically been used to artificially propagate the pathogen.
iStockPhoto pic of armadillo. God, they’re ugly.