What is CWD and What Can Be Done About It?

October 12th, 2023
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This is the first of three articles in which Doug Duren shares information about Chronic Wasting Disease (CWD) along with his experience and perspective as a landowner and hunter in Southwest Wisconsin’s CWD endemic area.


As the Fall hunting season begins, conversations in cafes, bars, farmhouses, and hunting camps turn to game numbers, habitat conditions, stand placement and other hunting strategies. If you want to liven up the conversation, say something like “Hey, what do you think about Chronic Wasting Disease (CWD) and what we should do about it?” I predict voices will get louder and you will hear a wide variety of opinions ranging from “it’s no big deal”, “it’s always been here”, “there’s nothing we can do about it” to “we should be doing what we can to control it” “I’m not hunting in CWD areas anymore”, “my significant other won’t eat venison anymore” and “I don’t know what to think”. 

I suggest before dropping that proverbial bomb into a conversation, we should all spend some time learning about CWD. You may hear some folks say, “not much is known about CWD.” Nothing could be further from the truth. A LOT is known about CWD, and more is being learned by scientists and hunters each year. To discuss the disease intelligently with other people, it’s important to be familiar with the science around CWD, and to then use logic and your own knowledge of deer and deer hunting to the conversation.

I don’t pretend to be an expert about CWD, but I learned a long time ago to talk to experts, no matter the subject, and then to think about what they’ve learned and apply it to the situation at hand. When it comes to anything about animals, I also apply what I’ve learned about animal husbandry from my farming experience. 

There is a wealth of information from reliable sources about CWD. It may be the most studied wildlife disease in history. Later in the article, I list the best resources for digging deep into the disease. There you will find science-based definitions, studies, data, and facts about what the best wildlife biologists in the world have learned and suggest can be done about CWD. 

First, let’s lay out the basics – What is CWD? 

“Chronic Wasting Disease (CWD) is a fatal, neurological illness occurring in North American cervids (members of the deer family), including white-tailed deer, mule deer, elk, and moose. Since its discovery in 1967, CWD has spread geographically and increased in prevalence locally. CWD is contagious; it can be transmitted freely within and among cervid populations. No treatments or vaccines are currently available. Chronic wasting disease is of great concern to wildlife managers. CWD is not known to infect livestock or humans. CWD is transmitted directly through animal-to-animal contact, and indirectly through contact with objects or environment contaminated with infectious material (including saliva, urine, feces, and carcasses of CWD-infected animals).”  Source: USGS Wildlife Health Center website 

The Basics of CWD in Layman’s and Hunter’s Terms

My family farm, where I’ve done 99% of my deer hunting, is located in Southwest Wisconsin. Chronic Wasting Disease was discovered in the region in 2002. I began learning about the disease almost immediately after the discovery, and as science has evolved and more is learned, I have kept up with the information by reading and speaking regularly to experts in the wildlife health field. I also speak to hunters, landowners, and the interested public about their experience with, and knowledge and ideas about the disease.

Here are known facts about Chronic Wasting Disease: 

  1. CWD is always fatal. It is a disease that, once contracted by a member of any of the deer species or other cervids (elk, moose, and caribou) and if that animal does not die by some other means, it will die from CWD or complications that are caused by it. 
  2. CWD is a transmissible, infectious disease. It spreads deer to deer and through contact with infected areas in the environment. Infected deer can spread the disease to other deer through natural deer behavior, like licking each other and other grooming. Infected deer carry the disease and emit it in their saliva, urine, and feces. So, it is also present in the environment in endemic areas and especially in areas where deer congregate. 
  3. CWD spreads slowly in infected animals. The length of time from when the animal contracts the disease to when it dies varies, but in Whitetail deer, the most common cervid species in North America, that time is 18-24 months. For most of time the animal is infected it looks and acts normal with the last few weeks being the time where the animal looks sick and “wastes” away. Unfortunately, almost the entire time the deer is infected it can spread the disease to others and leave infectious material on the landscape.
  4. CWD is found in all age classes and both sexes of deer in endemic areas. Although older bucks are the most likely to have CWD in areas where it has existed for some time, all deer are susceptible to contracting the disease. Older does are the second most likely to have CWD in endemic areas, but the longer the disease is present in an area, especially those with high populations, prevalence (the percentage of animals infected) grows in both sexes and all age classes of deer. 
  5. There is no known cure for CWD. Although research for a cure for the disease is ongoing, it seems unlikely that will ever be achieved. Therefore, doing what we can to prevent the disease from moving into animals in new areas and controlling prevalence where it exists, are the best we can do.  
  6. There are no confirmed cases of CWD infecting humans. Getting your harvested deer tested for CWD is generally available in nearly all states. The Center for Disease control and other health organizations recommend against eating meat from CWD positive deer.  Each person can make the choice about eating meat from a known infected deer. 

What We Can Do About CWD

Here’s a list of things we can ALL do to help fight CWD:

  1. Hunt! Keep hunting, start hunting, encourage other people to keep or start hunting! Enjoy the hunt. Concern about CWD is not a reason to stop hunting.  
  2. Continue to learn about members of the cervid family, their habitat needs and their habits. Learn as much as you can about these incredible creatures and conservation efforts on their behalf. Learning more about CWD will inevitably be part of that journey. 
  3. Support science-based research on CWD, its cause, prevention, and cure. We’re all in this together. Hunters, deer and elk farmers and the public all have a common interest in fighting CWD. 
  4. Support State and Federal wildlife agencies and wildlife biologists. Personal, business interests and politics can get in the way of good wildlife management. Like discussing your health with your doctor, it’s important and correct that we question, have expectations, and hold wildlife professionals accountable. But supporting the professionals and scientists who are trained and charged with protecting our natural resources is vital. These people have spent their careers and dedicated their lives to conserving and enhancing natural resources. They deserve our support.

Here’s a list of things we can do about CWD if you hunt in an area where CWD is known to exist:

  1. Again, Hunt! Take it seriously and use common sense precautions, but don’t let CWD discourage you from hunting and harvesting animals. Hunting is the best management tool we have to help meet population management goals, slow disease spread and reduce prevalence. 
  2. Learn about herd population dynamics, harvest goals and the reasons behind them. If you’re a landowner, consider allowing more access to hunters on your property to achieve management goals and speak with them about the need for herd and disease control. 
  3. When you harvest an animal, follow safe handling recommendations for handling deer and elk in CWD areas. 
  4. Get your harvested animals tested. The data from test results helps with the science of understanding spread and prevalence and can help agencies with management decisions. If you plan to eat the meat of a CWD positive animal, let your state agency know and add your name to the list of people who are doing so. This will help surveillance and research on the interface between CWD and humans.  
  5. Know and follow CWD regulations where you are hunting and anywhere you are transporting your harvested animal. Dispose of the carcass of the animal properly and demand that your state put in place measures to be able to do so. Most states where CWD is present have or are developing response plans. Proper disposal is basic carcass hygiene which and can slow the spread of the disease into new areas. 
  6. If you’re hunting in a CWD area, it’s likely there are restrictions on what hunting methods or lures you can use.  Even if it’s legal where you hunt, don’t use bait piles, urine, or attractants of any kind. They unnaturally congregate deer and elk where they encounter each other’s saliva, urine, or feces.  You may have heard the argument that deer are social animals and naturally congregate, lick and groom each other, lick branches, etc. so they will encounter each other naturally. The argument is since they already do it, it’s OK to continue bait and lures. While it is true that deer and elk will naturally congregate and have these kinds of exchanges, encouraging unnatural congregation and exchanges simply adds to the odds of exposure to disease. Bait piles especially encourage unnatural contact and cast prions in a small area. We can’t do anything about natural deer and elk behavior, but we can darn sure do something about ours. 
  7. Consider getting involved with efforts to educate other folks. Get reliable information and support groups and organizations who are helping with the effort.
CWD testing kiosk
CWD Testing Kiosk


Reliable Sources for Information on Chronic Wasting Disease

“The opinion of 10,000 men is of no value if none of them knows anything about the subject.”
-Marcus Aurelius

Information is being published about CWD almost daily and it can be confusing to know where to get reliable information. Here are a few of the best sources for information about CWD:

USGS National Wildlife Health Center “The USGS National Wildlife Health Center is the only national center dedicated to wildlife disease detection, control, and prevention in the United States. Our mission is to advance wildlife health science for the benefit of animals, humans, and the environment.”  Working as part of the US Government Department of the Interior, USGS WHC has been involved with research and information about Chronic Wasting Disease since its detection. Their website provides a range of information about CWD from basic FAQs to the latest research. https://www.usgs.gov/faqs/what-chronic-wasting-disease  

The Association of Fish and Wildlife Agencies “State, provincial, and territorial fish and wildlife agencies in North America have safeguarded fish and wildlife for over 100 years. The public entrusts these agencies with primary stewardship over vital wildlife resources. The Association of Fish and Wildlife Agencies lends collective voice to its agencies in fulfillment of that responsibility.” AFWA is a non-profit organization whose members are some of the best and brightest wildlife biologists in the world. Their collective work and Best Management Practices on CWD can be applied anywhere deer and other cervids exist. Follow the link to their CWD BMPs. https://fishwildlife.org/application/files/1315/7054/8052/AFWA_CWD_BMP_First_Supplement_FINAL.pdf 

Chronic Wasting Disease Alliance “The mission of the CWD Alliance is to promote responsible and accurate communications regarding CWD, and to support strategies that effectively control CWD to minimize its impact on wild, free-ranging cervids including deer, elk, and moose.” The CWD Alliance and their website is a joint project of the Boone and Crockett Club, Mule Deer Foundation and the Rocky Mountain Elk Foundation and other organizations. The website is easy to use and updated regularly. https://cwd-info.org/