Fri April 29, 2011
Armadillos Linked To Leprosy
Armadillos aren't known for being particularly cuddly. But a new study may offer a better reason never to pick up one of the armor-plated critters: they can spread leprosy.
Leprosy, also known as Hansens's Disease is a bacterial infection that can take three to five years to incubate and whose symptoms include a rash, stiffness and nasal stuffiness. Because leprosy is rare, many doctors don't recognize it right away. Most forms can be treated with antibiotics. There are between 150 and 250 cases of the disease in the US every year. Seventy percent of these cases come from traveling abroad to areas where leprosy is still common, like parts of Africa and Asia.
As for the remaining 30 percent? Richard Truman, a scientist at the National Hansen Disease Program in Baton Rouge, has found that armadillos in Louisiana and Texas may be partially to blame. Research he published this week in the New England Journal of Medicine follwed the trail of some unsolved leprosy cases.
"What we did was to show that the M. Leprae from armadillos and those U.S. cases without foreign exposure were highly similar, essentially identical, and significantly different from the M. Leprae we see internationally," Truman told KUT News.
M. Leprae is the bacterium that causes Hansen's Disease. The infection occurs most commonly in high-density armadillo populations, which in Texas are found along the coast.
"In the vicinity of Austin, we've probably looked at more than 700 armadillos out of that area and we've never found any evidence of the infection there," Truman said. "More towards the coast, say Corpus Christi or the Houston area, yes, we will find it."
The Texas Department of State Health Services says 26 cases of leprosy were reported in Texas last year. In fourteen of those cases, the patient reported contact with an Armadillo.
But Chris Van Deusen, a department spokesman, says that leprosy hard to catch, requiring repeated exposure. And he adds that 90 to 95 percent of the population is immune to it.
"We would encourage people to avoid armadillos as we would encourage them to avoid any kind of wild animal or wild game," Van Deusen said.
"There are certain populations that eat armadillo, or that capture them and process them. If you're going to do that you should absolutely wear gloves, protect your skin, wash your hands thoroughly as you would if you're dressing any wild game," he said. NPR's Adam Cole reported,
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.
"Leprosy is not a very robust pathogen," Truman says.
For these reasons, Truman says the risk of contracting leprosy from brief contact with an armadillo, or even from moving armadillo roadkill, is low. In the rare case that you do pick it up, antibiotics usually kill it.
Truman hopes his research will encourage doctors to consider the possibility of leprosy when diagnosing patients with its symptoms, even if they haven't been out of the country. So, a small number of patients in the South may be hearing the question: have you ever met an armadillo?
Ryland Barton reports for KUT News and ReportingTexas.com