This past fall many NSF&G members travelled to the east Kootenays to hunt whitetails and many of us were very successful (thanks to all the club members who helped make that happen for other club members!)

Some of the success took place in the Kootenay’s  CWD hotspot, close to Cranbrook, so CWD, a disease occurring far from North Van, is directly linked to freezers in North Van.  

Here’s why.

Chronic wasting disease (CWD) is a fatal, infectious disease that affects the nervous system of deer, elk, moose, and caribou. It’s caused by abnormal proteins called prions that build up in the brain and other tissues. The symptoms are weight loss, poor coordination, excessive salivation (drooling), lethargy, stumbling, and trembling. People who have seen CWD infected deer often describe them as being like zombies. 

 What the Heck is a “prion”? 
A prion is a misfiled protein that then induces more misfiling in normal variants of the same protein.  They start with a normal protein mutating onto a prion, and then, after mutation, causing other proteins to misfold, and that misfolding leads to cellular death.

Prions are responsible for prion diseases, known as “transmissible spongiform encephalopathy” (TSE)  affecting both humans and animals.  We know the names – CWD for TSEs in deer, mad cow disease when it happens in cows, scrapie when it’s found  in sheep, and Kreutzfeld-Jacob disease when it occurs in humans. 

(Click on the image to go to the Mayo Clinic for more information).

CWD spreads through saliva, urine, and other bodily fluids  and other deer become infected through direct contact with an infected animal, its feces or by consuming contaminated food or water.

It’s tough to kill the CWD prion. To destroy  it requires sustained heat for several hours at extremely high temperatures (900°F and above).  In other words? Once it’s in the environment we are not destroying it.   Prions can survive in the environment for many years 

It gets worse.  There is no known cure for CWD. If a deer or other ungulate gets it that animal will die, and before it dies it will spread the prions and other deer will die, but not before they spread the prions even further.  

Where Did It Come From? 
The exact origin is unknown but i was  first noticed in 1967 in captive mule deer at a US government research facility in Colorado that had previously held domestic sheep. The suspicion is that scrapie prions mutated into CWD prions.  It wasn’t identified as a transmissible spongiform encephalopathy (TSE) until the 1970s and was first found in the wild in Colorado in 1981 in elk.

CWD made it  to captive herds in Saskatchewan in the mid-1990s,  to wild cervids in Saskatchewan by 2000, and it has now turned up in 5 provinces (Quebec, Manitoba, Saskatchewan, Alberta and BC).  It also occurs in  Arkansas, Colorado, Illinois, Iowa, Kansas, Maryland, Michigan, Minnesota, Missouri, Montana, Nebraska, New Mexico, New York, North Dakota, Ohio, Oklahoma, Pennsylvania, South Dakota, Texas, Utah, Virginia, Wisconsin, West Virginia, and Wyoming.

CWD has also been found in reindeer and moose in the United States, as well as in Canada, Norway, Finland, and Sweden. 

 CWD infected deer are obviously sick once the infection has progressed, as the photo above shows, but not all CWD infected deer are that far along, so testing is vital before consumption. 

Are CWD Infected Animals Safe to Eat?

There has  been no known transmission of CWD to humans, but  experts continue to study the possibility of cross-species transmission.  Recall the to the best of our knowledge the CWD prion mutated from scrapie, a disease that affects sheep, a completely different species than deer or other cervids.  

On the other hand, although CWD has  been detected in predators’ feces, demonstrating that predators kill and eat CWD infected deer, there is no evidence that predators have actually been infected by CWD.  

It’s probably safe, therefore, for humans to eat CWD infected deer, but……

What is BC Doing About CWD?

The first thing BC has done, (with help from the BCWF, which NSF&G is a proud member of) is declare a CWD “hot zone”.  

The BCWF (of which we are a proud member) contributed to the organization and supply of freezers to drop off locations to collect heads for CWD testing.  All of the NSF&G club members who hunted these Must last year  went through the head drop off process, and some even ran into  Cait Nelson, Wildlife Health Biologist at the Ministry of Forests and the person in charge of BC’s CWD response.  There is lots of information from the Provincial government on how to handle CWD deer here.

So far the testing program has come up with  5 CWD positives, all in the Kootenay hotzone.  A 200 deer cull is currently underway around Cranbrook and Kimberly.  The goal is not so much to eradicate the deer population but to get a useful sample size in the areas that are CWD hot spots to determine the infection rate.  The government also says it will help reduce population density, but that’s going to take a lot more work and is still to come.

It’s worth remembering that not all of these deer are the typical urban or “town deer” that we sometimes imagine.  Most are deer from the large agricultural zones that are close to town.  They have few predators, little hunting pressure and lots of food.  Lots of deer close together leads to more infection, but those herds also send out young males who will then spread the infection.  

The East Kootenay Wildlife Association, the collection of BCWF clubs in that area, are working hard on CWD, including being involved in organizing the culls.  BCWF is also pushing hard on a CWD response. The government is another matter.  The government staff on the ground, like Cait Nelson, are fantastic, but we face the same challenge as always: we do not fund fish, wildlife and habitat enough in BC (meaning – contact your MLAs!). The president of the EKWA, Kevin Podrasky, is a friend of mine and is involved in that, and the BCWF supports using resident hunters do do the work. 

I (Rob Chipman) and a BCWF representative on the Provincial Hunting and Trapping Advisory Table (PHTAT) .  PHTAT is a group of stakeholders that meets with government on a regular basis, and our next meeting is at the end of this month.  CWD will be coming up (as will proposed updates for LEH). 

More info on CWD:

BCWF Info

BCWF Webinar with Cait Nelson 2024 

BCWF Webinar with Cait Nelson 2023

BCWF Webinar with Cait Nelson 2021

CWD in Idaho

CWD in Montana

Utah Division of Wildlife Resources

CWD Info.org