What is chronic wasting disease? Could ‘zombie deer’ disease spread to humans through infected meat?

WHO says we should keep all agents of known prion diseases out of human food chain

Chronic wasting disease (CWD) has been found in both the Upper and Lower peninsulas of Michigan.

CWD is a neurological disease that affects deer, elk and moose. It causes a degeneration of the brain. It can cause emaciation, abnormal behavior, loss of bodily functions and eventually death.

Once an animal is infected with CWD, it will not recover. There is no cure. There is no evidence that CWD can be naturally transmitted to humans or other animals.

Last year, 7,229 deer were tested for CWD and 25 tested positive.

2021 Michigan Chronic Wasting Disease Surveillance Plan (Michigan DNR)

Read: Experts fear disease turning Michigan deer into ‘zombies’ could one day spread to humans

What is Chronic Wasting Disease (CWD)?

CWD is caused by a normal protein, called a prion, that folds incorrectly.

It is transmitted through direct animal-to-animal contact or by contact with saliva, urine, feces, blood, carcass parts or infected soil.

Prions are extremely resistant in the environment and can stay infectious for years.

Symptoms of Chronic Wasting Disease in deer

It has a long incubation period, usually around 18 months but can take as long as two years for symptoms to show up.

In most cases, animals with CWD don’t have any visible symptoms of the disease until the last few months of the disease’s cycle.

That means that most infected animals are virtually impossible to distinguish from healthy, non-infected animals.

Because CWD affects the neurological system of an infected animal, they usually die from predators, vehicle collisions or other diseases before CWD is visible.

If an infected animal survives to the end stages of the disease, the most obvious sign is emaciation. CWD leads to gradual loss of body condition. Other symptoms include excessive drinking and urination.

Deer will have fewer interactions with other animals, listlessness, lowering of the head, blank facial expression and repetitive walking in set patterns. In elk, you may see hyper-excitability and nervousness. Excessive salivation, drooling and grinding of the teeth have also been seen.

Video: Why the DNR has been able to make deer hunting regulations in Michigan less restrictive

Can humans get chronic wasting disease?

According to the CDC, there have been no reported cases of CWD infection in people.

Some animal studies indicate that CWD poses a risk to certain types of non-human primates, like monkeys, that eat meat from CWD-infected animals or come in contact with brain or body fluids from infected deer or elk.

Those studies raise concerns that there might also be a risk to people. The World Health Organization has recommended that it is important to keep the agents of all known prion diseases from entering the human food chain.

Is there a risk of CWD spreading to humans?

If CWD could spread to people, the CDC believes it would most likely be through eating infected deer and elk. As of now, it is not known if people can get infected with CWD prions and there is no strong evidence for the occurrence of CWD in people.

The CDC said hunters should take some precautions when hunting in areas with known cases of CWD.

Do not shoot, handle or eat meat from deer and elk that look sick or are acting strangely or are found as road kill. When you’re field-dressing a deer you should wear rubber gloves, and minimize how much you handle the organs -- particularly the brain and spinal cord tissues.

Hunters should not use household knives or other kitchen utensils for field dressing.

If you have the animal tested for CWD and the test comes back positive, you should not eat that animal.

How to report a sick deer in Michigan

If you see a deer that appears ill you should take note of the location and then reach out to the Michigan Department of Natural Resources.

You can click here to report a sick deer online or contact your local DNR office. If you make the report online you will be asked for personal information, details about the deer and you can upload photos if you took any.

Hunter CWD self-sample kits

Michigan is offering free lymph node shipping kits that include free CWD testing for several counties.

Click here to learn more about the self-sample kits.

Read: More Michigan hunting coverage

About the Author:

Kayla is a Web Producer for ClickOnDetroit. Before she joined the team in 2018 she worked at WILX in Lansing as a digital producer.