Leprosy may not be the plague it once was, but an estimated 150 to 250 people contract it in the United States each year. Two-thirds of U.S. patients acquire the disease after traveling to places such as India, Brazil, Africa and the Philippines, where leprosy still affects about 250,000 people. As for the other one-third, new research suggests they may become infected by armadillos.
Leprosy, as known as Hansen’s disease, joins infectious diseases such as HIV/AIDS on the list of illnesses that can jump species. Interestingly, many experts believe humans first introduced it to the armadillo population, rather than the other way around. There are no recorded instances of leprosy in the Americas before Christopher Columbus arrived, and armadillos are not native to any other part of the world. Now, they’re giving it back to us.
Armadillo habitat ranges from Colorado to North Carolina. In some regions, as many as 20% of the armadillo population is infected. Yet the bacteria that causes leprosy, Mycobacterium leprae, is very fragile. It doesn’t live very long in laboratory conditions or elsewhere outside its host. Armadillos and humans seem to be the only places where Mycobacterium leprae thrives.
Via New York Times:
The fragility of the leprosy bacterium suggests that infections result from something more than casual contact with an armadillo, [said Dr. Richard W. Truman, an author of the armadillo study, which was published Wednesday in The New England Journal of Medicine.]
“The important thing is that people should be discouraged from consuming armadillo flesh or handling it,” Dr. Truman said.
Dr. Truman and the other researchers used genetic sequencing to prove that the additional one-third of U.S. leprosy infections are transmitted by armadillos. These cases were primarily in Louisiana and Texas, where armadillos are hunted and eaten.
Leprosy is treatable with antibiotics, but doctors in the U.S. are often slow to diagnose the disease in patients who have not traveled abroad. Patients who are not diagnosed in the early stages can suffer severe nerve damage. Researchers hope the new data will encourage doctors to consider a patient’s armadillo history when making a diagnosis.
Photo credit: austinevan