As if the public health emergency caused by the Zika virus infection is not alarming enough, another new medical threat is emerging in the United States.

In its December 2015 "Emerging Infectious Diseases" report, the Centers for Disease Control and Prevention (CDC) warned of rising cases of leprosy in the U.S., particularly in the states of Mississippi, Alabama, Georgia, and Florida.

The infectious disease—caused by the bacterium known as Microbacterium leprae in the scientific community, and whose patients were once placed in isolated areas—was reported to be transmitted not just by human beings but also by slow-moving animals known as armadillos.

"Leprosy appears to be an emerging infection of armadillos throughout the southeastern United States," Dr. Rahul Sharma from the CDC explained in an article on hcplive.com.

Sharma and colleagues at the National Hansen's Disease Program Laboratory Research Branch in Baton Rouge, LA, screened a total of 645 armadillos from eight areas in the southern U.S. not known to harbour enzootic leprosy, and made an alarming discovery.

Sharma's team found a new leprosy genotype in the animals, which has already been transmitted to humans. Therefore, cross-species infections have already occurred.

What's more alarming is the fact that the mechanism by which the bacterium was transmitted from armadillos to humans still remains undetermined.

The research team suspect that the bacterium is transmitted to humans through direct exposure to blood of dead armadillos, said to be "the host of choice" for leprosy.

Sharma further explained that the leprosy bacterium attacks a person's peripheral nerves early in the course of the disease, which leads to a patient's evident disfigurement and deformity.

"There are tremendous misconceptions about leprosy...extensive neuritis and nerve damage underlies the gross pathology and deformity we sometimes associate with leprosy...appendages don't just fall off, lack of sensation makes them very susceptible to secondary injury and trauma," he explained.