A new study has fingered armadillos as the source of about a third of the cases of leprosy (Hansen’s disease) in the southern United States. (The other two thirds get it overseas; that remaining indigenous source of leprosy had been a mystery.) Casual contact isn’t enough to catch it; eating armadillo meat is a more reliable vector for spreading Mycobacterium leprae — and yes, people do eat armadillo in the areas where these cases of leprosy have been found. So stay away from the armadillo chili!
But it’s not simply that armadillos give M. leprae to humans: we gave it to them first.
[Lead researcher Richard] Truman says there was no leprosy in the New World until European settlers arrived. Somehow armadillos contracted the disease, and now about 15 percent of armadillos carry it. They are ideal hosts, because M. leprae likes their low, 89-degree body temperature. It can’t thrive at a human’s core temperature, which is why it only attacks our cooler extremities.