Hunters: Beware of ‘zombie’ deer

An incurable infectious brain disease that’s deadly to deer, elk and moose continues to stalk the land. By 2015, it had expanded to 23 states and two Canadian province since it was first identified in a Colorado captive mule deer research center in 1967.

Now, with Washington state’s first case of chronic wasting disease confirmed in an adult female white-tailed deer that was found dead north of Spokane, the disease, CWD, has been identified in 35 states and 6 Canadian provinces.

In other recent news, an Indiana county is reporting its first case of chronic wasting disease (CWD), less than a year after the state’s first detection.

A 2.5-year-old white-tailed buck in Posey County tested positive after being harvested by a hunter.

Also concerning is that just several weeks ago, the Wyoming Game and Fish Department announced its second and third cases of CWD had been discovered on an elk feedground — both detected in cow carcasses at the Dell Creek Feedground in the Bondurant area. 

CWD travels

This is a disease doesn’t stay put. It has been found in South Korea; in free-ranging reindeer, moose and red deer in Norway; in free-ranging moose in Finland; and in free-ranging moose Sweden.

Caused by malformed proteins called prions, it can be confirmed through testing of lymph nodes or brain tissue, at the base of the skull. The lymph nodes of the deer that tested positive in Eastern Washington in July were submitted to the Washington Animal Disease Laboratory in Pullman at Washington State University.

Much smaller than bacteria, prions are single proteins that cannot be destroyed by typical “kill strategies” such as extreme heat or ultraviolet light.

There is no vaccine or cure for this disease. It is spread through urine, feces, saliva, blood, semen, deer parts, and especially via live deer. Not only that, plants and roots can bind, uptake and transport infectious prions. And plants infected with the prions were able to transmit the disease when animals were fed the contaminated plants.

This is a disease that has baffled scientists for decades. Where did it come from, and why is it spreading across the landscape?

“”Our biggest challenge is to try to minimize its spread.” said Melia T. Devivo, the Washington State Fish and Wildlife Department’s lead for its CWD program,

How do you know if an animal has CWD

Drastic weight loss, stumbling and lack of coordination, drooling, excessive thirst or urination, drooping ears and lack of fear of people are signs that an animal is infected with CWD. No wonder that some people refer to the infected animals as “zombie deer.”

But Devivo said that because it takes so long — sometimes several years — for the disease to become apparent in an animal, some animals with CWD look healthy. It’s a year-round disease — not seasonal.

Because CWD moves slowly through a population, and because it kills individual deer slowly, its impact is not dramatic or rapid, which is why some hunters believe CWD is not a serious problem.

However, CWD will gradually grow in prevalence if it is not actively managed, and it will eventually reduce populations.

“CWD is the biggest threat to the future of deer hunting,” says the Theodore Roosevelt Conservation Partnership on its website Go to the website to watch how fast the disease has spread across the United States since 1968.

Where is it?

Go here to see the regions in the U.S. where CWD has been confirmed. 

Deer and other cervids — members of the deer family — killed in those regions need to be tested and also butchered according to state rules.

What about food safety?

While no cases of transmission to humans have been reported, the Centers for Disease Control recommends that you do not consume meat from a CWD positive deer. And the National Deer Association encourages all hunters to adhere to the agency’s  guidelines regarding the handling or consumption of venison from CWD positive deer.

According to CDC, the high-risk parts include the brain, eyes, backbone and spleen.

That’s why it’s important to bone out your harvest to avoid moving sensitive parts of the deer that could carry CWD.

Boots on the ground: How hunters can help

Go here for some advice from the National Deer Association about how hunters can help prevent the spread of CWD.

        •       Know if you hunt in a CWD management zone where the disease has been found or will be traveling to hunt in a CWD zone. This is basic, crucial knowledge that helps you learn and follow regulations and guidelines designed to prevent the spread of CWD out of these zones.

  •     If you hunt in a CWD zone, submit all harvested deer to the state wildlife agency for CWD testing (and wait for satisfactory results before consuming the venison). Testing helps the agency keep tabs on the disease’s prevalence and location, which is crucial information for protecting the deer resource and hunting.

        •       If you hunt in a CWD zone, dispose of deer carcasses inside the zone following the recommendations of that state’s wildlife agency. Leave the zone only with boned-out meat, antlers connected to clean skull plates, clean hides, or clean jawbones/teeth. Most states now ban the importation of whole deer carcasses and are enforcing these laws.

        •       If you kill a deer that tests positive for CWD, that’s a good thing. You removed an infected deer from the woods, which helps fight the disease. Don’t let it get you down. Collect your replacement tag from the state wildlife agency, keep hunting, and keep testing the deer you harvest.

        •       If you do not hunt in a CWD zone, but your state wildlife agency asks you to voluntarily submit deer for CWD testing, respond to the call for help. Submit your deer for testing. Discovering new CWD outbreaks early is critical to reducing the impact.

        •       Report sick deer immediately to your state wildlife agency. Whether you see or harvest a deer that appears unhealthy, the state wildlife agency may want to examine and test the deer. Early detection of CWD is very important, so don’t hesitate to report sick deer.

        •       Harvest an appropriate number of does to maintain balance between deer density and forage availability where you hunt. Diseases that spread deer-to-deer like CWD move more slowly across the landscape in healthy deer densities.

Devivo said that CWD is most prevalent in buck deer simply because buck deer have a larger home range than do does, and they have more contact with other deer because of breeding and fighting with other bucks.

        •       Connect with your state wildlife agency for information, even if you don’t hunt in or near a CWD zone. Sign up for the agency’s e-newsletter, follow them on social media, and attend public hearings whenever offered. Stay informed about all wildlife issues in your state, including deer health and hunting regulations.

What about ‘captive’ cervid farms

Sometimes called “deer farms,’  captive cervid facilities are located on privately owned property. There are more than 10,000 captive-cervid breeding and shooting facilities in North America.

According to a study from Texas A&M University, they are “perhaps the fastest growing industry in rural America.”

The industry includes raising native or exotic cervids sold for such things as antlers, meat, breeding and even urine, which is used as an attractant. In some cases artificial breeding is used to produce larger cervids and antlers, which bring in good prices.

When it comes to CWD, what’s particularly troubling is that these operations often transport the animals to locations across North America, thus raising the risk of spreading the disease to other locations. 

Then, too, since they’re often raised in dense populations, there’s more risk of CWD spreading should an animal have it. And even though the animals are fenced in, they sometimes “escape” and come into contact with wild cervids. There’s also the possible problem of “fence-to-fence” contact between captive and wild cervids.

The annual estimated economic impact of the cervid industry in Minnesota by 2012 was $17 million, with an estimated 1,287 jobs supported by this industry.

However, on the flip size of the coin, economic losses associated with CWD’s impact on the captive cervid industry for places like Alberta, Canada, range from $12 million (for prevention measures like improving fencing) to hundreds of millions (for compensation by the government for depopulation).

“The impact of CWD on the captive cervid industry is not a future problem but a growing and ongoing reality,” says the report. 

Go here for more information about captive cervid farms.

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