- Chronic wasting disease, or CWD, has been reported in 24 states and two Canadian provinces.
- It infects deer, elk and moose.
- Some call it "zombie deer disease" because of its symptoms.
- There have been no reports of a human being infected.
An infectious diseases expert has warned that chronic wasting disease, which is killing deer in the Upper Midwest and has been reported in at least 24 states, could infect humans in the near future.
Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota, told lawmakers recently that chronic wasting disease (CWD) should be treated as a public health issue, the Pioneer Press reported.
"It is probable that human cases of CWD associated with the consumption of contaminated meat will be documented in the years ahead," Osterholm said. "It is possible that the number of human cases will be substantial and will not be isolated events.”
He was speaking at a hearing last week at the Minnesota Capitol, where legislators introduced bills to address the state's growing problems with CWD. There has been some tension about how big a concern CWD should be for hunters, who can have deer they kill tested for the disease.
CWD is still rare in Minnesota, but the state has seen more than 35 cases in southeastern Minnesota in farmed and wild deer since 2016, the Pioneer Press said in a separate report.
As of January, CWD has been found in deer, elk or moose in at least 24 U.S. states and two Canadian provinces, the Centers for Disease Control and Prevention reported. It is also found in farmed deer and elk.
There have been no reported cases of CWD infection in people. However, the CDC and World Health Organization recommend against eating CWD-infected deer.
CWD is caused by a malformed protein — or prion — that infects animals’ brains, according to the University of Minnesota's College of Veterinary Medicine. Because of its symptoms, some people have called it "zombie deer disease."
The CDC said symptoms include drastic weight loss, stumbling, lack of coordination, listlessness, drooling, lack of fear of people and aggression – the sort of thing you can see each week on "The Walking Dead." An animal could carry the infection for more than a year and not show any signs of CWD.
Scientists think the disease is spread through contaminated body fluids and tissue or through environmental exposure, such as in drinking water or food.
Prion diseases like CWD have made the jump from animals to humans before.
CWD belongs to the same family of diseases as bovine spongiform encephalopathy – or "mad cow disease." The human form of the infection is called variant Creutzfeldt-Jacob disease.
The Minnesota Department of Natural Resources advises deer hunters to have deer tested for CWD and to have meat processed and wrapped individually.
The agency also suggest that hunters wear rubber gloves when butchering deer, minimize handling of brain and spinal tissue and wash hands thoroughly after handling a carcass.
DNR also recommends not eating brain, spinal cord, eyes, spleen, tonsils, and lymph nodes.
Cooking or freezing infected meat will not remove prions because they are very resistant to heat and freezing temperatures, the agency said.
Osterholm, who tracked the emergence of mad cow disease for decades, told the Minnesota lawmakers that many in the public health and beef industries did not believe it could infect people, the Pioneer Press reported.
“If Stephen King could write an infectious disease novel, he would write about prions like this,” said Osterholm.