Do more armadillos in Kansas mean more leprosy?

Armadillos — one of Kansas’ newer and most unusual, animals — continue to increase their range and population in the state.

So, does that mean you might catch a dreaded disease from the little armor-plated, leprosy-carrying animals?

Experts say it’s certainly possible, but highly improbable.

“Next to humans, we know armadillos are the only other natural host for leprosy,” said Ramanuj Lahiri, a Louisiana based biochemist who specializes in leprosy research. “A lot of studies have been done, and (infection rates) vary from locality to locality. The most we’ve seen is slightly more than 20 percent of the armadillos carry the disease. The least we’ve seen is 5 percent.”

None of that testing has been done in Kansas, nor have there been any population counts of the animals. But biologist Ken Brunson of the Nature Conservancy of Kansas said armadillo numbers seem to be increasing annually.

Still, Lahiri said the chances of someone contracting leprosy, called Hansen’s Disease in the medical community, from a Kansas armadillo are “extremely remote.” But his group, the National Hansen’s Disease Program, is preaching caution and educating people on how to avoid contracting leprosy from an armadillo.

Thousands of miles of migration

Fossilized records show nine-banded armadillos, the only kind native to North America, have walked the Earth roughly 1 million years. They’ve only been common in parts of Kansas the past 25 years.

“The 1981 Mammals of Kansas book characterizes armadillos as being rare in the state,” said Brunson. “When I first came down to Pratt in the mid-70s, they were a real rarity. That’s a lot different now. They’re a pretty common feature around here. Now we’re getting more and more records of them in northern Kansas. They’re not much a surprise any more.”

It appears nine-banded armadillos have been following their pointy snouts northward for several centuries.

Several sources say nine-banded armadillos were once native only to Central America and southern Mexico, and their northward migration was noted in the 1700s. They crossed the Rio Grande into southern Texas in about 1850 and weren’t common in southern Texas until the late 1800s. They’re now the Texas state mammal.

Biologists aren’t sure why nine-banded armadillos keep expanding northward. Initially, it could have been to escape being hunted in Central America and Mexico. The lowering of rivers for irrigation and flood control may have helped. Brunson said many theorize the migrations have been spurred by the overall warming of the world’s climate.

Stan Roth, a retired biology teacher from Lawrence, said his research showed they didn’t cross the Red River into Oklahoma until the 1920s. He thought the first Kansas documentation was near the Oklahoma state line in the 1940s.

“But they remained very rare in Kansas for a long time after that,” said Roth. “Starting 20 years ago, I started putting pins in maps where armadillos had been seen in Kansas. The first map lasted a while. Now I’m on my sixth map, I think, because I keep putting so many pins in them.”

Armadillos have been documented in all 105 Kansas counties, but the southern two or three tiers of counties remain their stronghold. They can survive in about any habitat in Kansas, but prefer area with some vegetative cover. Omnivores, they’ll eat about anything. Brunson said their preference is insects, but they’ll also eat small reptiles, amphibians, the eggs of ground-nesting birds, crops, fruits and garden vegetables.

The entire southeastern part of the U.S. now has strong armadillo populations and they’re found as far north as southern Illinois.

Wherever a nine-banded armadillo is found, there’s a chance it’s carrying leprosy.

Disease not as horrible as once believed

Leprosy has been around since at least 1,500 B.C. and is caused by a bacterium called Mycobacterium leprae. It’s found worldwide.

Lahiri says there’s a lot still not known about leprosy, such as exactly how it’s transmitted between humans, though science suspects it may be through nasal fluids. With armadillos, it’s probably from direct human contact with an infected animal’s flesh or blood.

Leprosy is not easily contracted.

“We believe most of the population, 95 percent, is naturally immune to leprosy,” said Lahiri. “It also is slow developing and can take three to five years for the symptoms to begin to show. Also leprosy can be cured. It is easily treated with a three-drug cocktail and treatment usually takes six months to two years. It’s all very easy.”

Lahiri’s group describes leprosy as “very rare” in the U.S., with often less than 200 new cases annually. He said figures from 2015 indicate around 200,000 new cases reported globally. Most are in impoverished areas in countries like India, Nigeria, Indonesia and Myanmar. An estimated 5.5 million people are infected worldwide.

Left untreated, the disease leads to skin sores, nerve damage and muscle weakness. Eventually it can lead to crippling of the hands and feet, blindness and paralysis. Lahiri said it’s a myth that leprosy can cause appendages to fall off. If that happens, it would be because of secondary injury.

Most of the new cases in the U.S. are probably contracted abroad, in places where the disease is more common.

In 2011, the New England Journal of Medicine confirmed it’s possible some Americans with leprosy may have been infected by armadillos.

Two years ago, some medical experts in Florida said an increase in the state’s leprosy rate might be because of increased armadillo populations and human encroachment on armadillo habitat.

Undocumented in the New World prior to colonization, Lahiri said scientists believe humans first passed the disease to nine-banded armadillos One of the few things the two species have in common is the ability to host the bacterium that causes the disease.

Caution advised

Lahiri said humans handling the tissue and blood of infected armadillos are the most likely to contract leprosy from the animals. (Some people eat armadillos, saying it’s a fine-grained meat reminiscent of pork.)

Anther possible contamination scenario would be someone moving a dead armadillo to another location or someone handling a live armadillo.

“We don’t recommend handling armadillos, but if people do they should take general hygienic measures” said Lahiri. “They should wear gloves. The most simple thing you could do would be to wash your hands well with soap and warm water if you’ve been around an armadillo.”

He said anyone with exposure to armadillos who develops symptoms of leprosy – skin growths or lesions – should see a dermatologist.

Brunson said people also need to be aware that rabies has been documented in Kansas armadillos. They can also inflict some nasty scratches with the over-sized claws they use for digging up food and creating burrows.

Roth said he rates those claws as the most dangerous part of an armadillo.

“They don’t hardly ever bite,” he said. “if they do, they don’t really have enough teeth to inflict much more of an injury than the bite of a grasshopper. I still consider armadillos pretty harmless.”

This story was originally published August 27, 2017 at 8:42 AM with the headline "Do more armadillos in Kansas mean more leprosy?."