CWD in deer: What are the signs, and is the meat safe to eat?

(NEXSTAR) — Deer hunting season is upon us across the Midwest, prompting a reminder from wildlife officials: Be on the lookout for chronic wasting disease, or CWD.

CWD is a contagious, fatal, neurological illness that can impact not only white-tailed deer, but other North American cervids like mule deer, elk, and moose. It was first discovered in the U.S. in 1967 and has since been detected in more than 30 states, though officials note it may be present in other states but not yet detected.

If you’re planning to hunt any deer this year, here are four things to know about chronic wasting disease, including whether it can impact humans and if an infected deer’s meat is safe to eat.

What is chronic wasting disease?

Often referred to as CWD, chronic wasting disease is a prion disease, which means the proteins in the body are misfolding. This will cause symptoms that will eventually lead to death, the Centers for Disease Control and Prevention explains.

CWD is contagious and believed to be spread when an animal comes in contact with an infected animal’s saliva, blood, urine, feces, or carcass. It may also spread through the environment, the CDC notes, like soil, drinking water or food.

“Once an animal gets sick, the disease moves to its brain and spine and eventually kills the animal,” the CDC says. There is no treatment or vaccine for CWD.

What are the signs and symptoms of CWD?

A deer may not show any signs of CWD until 18 to 24 months after becoming infected, according to the U.S. Geological Survey.

Arguably the most obvious sign is drastic weight loss, or “wasting.” You may also notice the deer stumbling or lacking coordination, lacking fear of people, or drooling. Additional symptoms include drooping ears, an appearance of listlessness, or excessive thirst or urinating.

A white-tailed deer showing symptoms of chronic wasting disease (M. W. Miller, Colorado Division of Wildlife, via the Associated Press)

The Wisconsin Department of Natural Resources lists other behavioral symptoms linked to CWD: teeth grinding, a rough dull coat, walking in set patterns, and difficulty swallowing.

Just because a deer (or other cervid) displays any of these signs, it does not mean they have CWD. The symptoms may have other causes, the USGS explains. The only way to confirm a deer or animal has CWD is through testing.

Think your deer may have CWD? Here’s what to do

Testing requirements and availability may vary by state. In parts of Ohio, for example, deer harvested on certain days must be submitted for sampling. Colorado has also designated specific areas for CWD testing this year.

In Wisconsin, all hunters are encouraged to test their deer using either self-service kiosks, where a deer head with 5 inches of neck can be dropped off; cooperating partners that can collect the head for sampling; at-home lymph node extraction kits; and appointments with DNR staff.

It’s best to check with local wildlife officials for their recommendations regarding chronic wasting disease in deer and other animals.

Is meat from a CWD-positive deer safe to eat?

First, it’s important to note that scientists have not yet found strong evidence that CWD can infect people. There have not been any reported cases of CWD in humans either.

The CDC notes, however, that there is concern that the disease could pose a risk to humans. A report published earlier this year suggested that two hunters contracted Creutzfeldt-Jakob disease, another fatal prion-related neurological disorder, after eating venison from deer infected with CWD. The researchers behind the study noted the causation was “unproven” and that further investigation is needed.

Because of this potential risk, the CDC and the World Health Organization advise against eating venison from a deer that tests positive for CWD.

The Wisconsin Division of Public Health recommends following all safe handling precautions when dealing with a deer, which includes wearing rubber or latex gloves when field dressing the carcass; removing the organs; minimizing contact with the brain, spinal cord, spleen, and lymph nodes; and thoroughly cleaning the knives and other equipment used.