Armadillos, people and leprosy: There’s history here

Researchers at the National Hansen’s Disease Program in Baton Rouge, La. -- a federal government program that studies leprosy and treats 3,600 Americans with the disease -- announced Wednesday that they had figured out the source of some mysterious cases of the illness in the Southern United States.

Patients got leprosy from contact with wild armadillos.

The team’s study, which was published in the New England Journal of Medicine, used cutting-edge genetic techniques to look for similarities in strains of the disease infecting armadillos and people in the region. It found striking similarities, concluding that the data strongly implicated armadillos as a source of human infection.

While this marks the first time scientists have documented critters giving people the disease -- which is now easily treatable -- it’s hardly the first time armadillos and people have crossed paths when it comes to leprosy research.


Indeed, for the better part of 50 years, researchers have depended on armadillos to study leprosy and its effects on humans. That’s because the bacterium that causes leprosy, Mycobacterium leprae, is a bit of a weakling, and can’t be grown in a dish the way many others can. Back in the 1960s, laboratory scientists sought other species that they might be able to use to cultivate the bug.

Because it was known that M. leprae thrived in parts of the human body with a low temperature -- notably, in the extremities -- investigators tried infecting a number of creatures with low body temperatures with the bacterium. After making attempts on frogs, catfish, snakes and other animals, they eventually stumbled upon the one beast on earth, other than people, that harbors M. leprae naturally: the nine-banded armadillo, which has a body temperature of about 91 to 95 degrees Fahrenheit.

Labs studying leprosy have depended on the armadillo ever since. People avoiding leprosy might want to keep their distance, however.



Read the Los Angeles Times story about new research linking wild armadillos and cases of leprosy in people in the Southern U.S.