“Can this form of leprosy be carried by armadillos?”
The armadillo is not a carrier of leprosy. It just so happens that Mycobacterium leprae will only grow in living tissue of a certain temperature and not on laboratory medium like agar plates. The footpads of mice were once used, but someone found out that the bacterium grew well in armadillos in a lab setting. They do not act as “carriers” in the wild.
“The armadillo is not a carrier of leprosy.”
What do you make of this then?
“It was long thought only humans could get leprosy. Then in the late 1960s researchers speculated that armadillos might be a good test bed for leprosy research because (a) M. leprae thrives in cooler parts of the body (feet, nose, ears, etc.); (b) armadillos have a relatively low body temperature as mammals go, 30 to 35 degrees Celsius compared to 37 degrees in humans (98.6 Fahrenheit for you retro types); (c) armadillos live long enough, 12 to 15 years, for this slow-acting disease to emerge; and (d) armadillo litters almost invariably consist of identical quadruplets, which was useful for genetic experiments.
Aspects of this conjecture might seem far-fetched (I’m thinking of the low body temp part), but it panned out. Several nine-banded armadillos, the type found in the U.S., were inoculated with leprosy germs and came down with full-blown cases of the disease.
Later the researchers discovered something odd: some armadillos already had leprosy. At first they thought the animals had escaped from the leprosy-inoculation experiment or become infected through contact with the lab’s waste. But eventually these possibilities were ruled out. Nine-banded armadillos, of which there are 30 to 50 million in the southeastern U.S., are believed to be the only significant natural reservoir of leprosy apart from humans. (A few cases have been found in chimps and mangabey monkeys in Africa.) How the armadillos got leprosy in the first place nobody knows. But there you are.” (From the Straight Dope)