“In this case, you’re not playing a slot machine to get all three of your numbers to line up, you’re playing like a casino full of slot machines,” Truman says.
“If it’s like two apple, three apple, four apple, and a 7-bar or something like that, and you find that on four or five different machines simultaneously, that’s the relationship,” he says.
Researchers hit the jackpot when they found a previously unknown strain of M. Leprae in 28 of the 33 wild armadillos they captured and in half of skin samples taken from patients.
The human bacterial samples came from frozen tissue, and in some cases, researchers didn’t have access to the patient’s full history. In 15 patients who were asked about contact with armadillos, seven said they’d never had contact with the animals, while eight said that they had.
One reported frequently hunting, cooking, and eating armadillos. His case prompted researchers to caution against handling or eating the animals.
Since the 1970s, scientists have recognized that armadillos could carry the bacteria and develop full-blown leprosy infections -- they have the lower body temperatures and longer life spans that the bacteria need to thrive, and it was suspected, based on case reports, that the animals could pass the bacteria to people.
But this new study marks the first time that an animal reservoir for the disease has ever been identified, and it means that in other parts of the world, where leprosy is much more common, animal reservoirs may be important in how the disease persists in the environment.
“Never before have we had the ability to have a biological link between organisms and cases, and now we do, which should then propel us forward being able to better deduce the risk factors that are important in transmission of the infection or that may then be perpetuating leprosy not just in the United States, but also worldwide,” Truman says.
The Risk for People
People are probably not at any greater risk than they were before, experts say.