A true and present danger: chronic wasting disease in white-tailed deer
Chronic wasting disease is an incurable, always fatal degeneration of the brain termed, "transmissible spongiform encephalopathy."
It is transmitted from animal to animal through contact with urine, feces and saliva. The agent is a misfolded protein called a prion. Prions are virtually indestructible and can persist in the environment for years.
The disease is related to other prion diseases such as scrapie (sheep), bovine spongiform encephalopathy (mad cow disease) and human kuru and Creutzfelt-Jacobs disease (humans).
CWD was first identified in captive mule deer in the 1960s and has now been identified in six species of deer and elk. Wisconsin presently has 421 licensed deer farms in the state. In 2001, the United States declared a state of emergency and since that time, the situation has gotten much worse. It has now been confirmed in 24 states, three Canadian provinces along with the countries of South Korea and Norway.
Testing for CWD in Wisconsin first began in 1999. The first case of CWD was identified in southern Wisconsin in November 2001 and since then has spread dramatically with 43 of the 72 counties presently affected in a baiting and feeding ban on white-tailed deer. In 2010, the state developed a disease response plan which was to be reviewed periodically through 2025.
The incidence of CWD has been shown to be higher in males than females. In the affected areas over the last 14 years, it has increased in males from 8-10 percent to 30 percent and in females from 3-4 percent to 14 percent. This rate is alarming and will continue to spread until the tipping point is reached. At the recent county deer advisory committee meetings held across the state, an updated report on the spread of CWD was provided. The data presented was viable and valid. The potential outcome is not very encouraging if nothing is done.
A CWD comprehensive analysis was provided in a recently published scientific article, as an "Alliance for Public Wildlife Living Legacy White Paper," entitled, "The Challenge of CWD: Insidious and Dire" (March 2017).
It was co-authored by several highly regarded experts on the subject, including Dr. David Clausen, a veterinarian from Amery and also a former Natural Resource Board member.
The article stresses what part of the title indicates, CWD is an "insidious and dire" disease. It is relatively new on the scene and could have possibly been transformed from the scrapie prion disease in sheep into this highly infectious disease of deer and elk. Transmission occurs from animal-to-animal, mother to offspring and from exposed plants and other surfaces. According to the article, CWD has clear population impacts and is now deemed to be the greatest-ever mass of infectious prions in global history. The "good news" is that the vast majority of our deer herd is disease free.
According to the article we need to:
• Contain the geographic spread of CWD by enacting and enforcing an immediate ban
on the movement of all live animals, all potentially CWD-infected carcasses, animal
parts, products, exposed equipment, trailers, or other sources of infectious materials.
• Mandate and implement for hunters, convenient, cost-free, rapid testing of all deer harvested from CWD-affected areas;
• Ensure that no CWD-infected material reaches the food or feed chains, and that it is
instead properly disposed; and
• Establish and fund accountable research and science-based policy to protect public
interest (health, wildlife and related industries, agriculture, our economies and
The threat is very real and will not go away.
We need to be proactive in addressing this catastrophic disease that will affect everyone. Imagine the steps that would need to be taken if CWD is shown to affect cattle or even be suspected of being cross-linked to humans.
What is so unique to this disease agent, called a prion, is that it is not even alive. We can no longer sweep the facts under the rug, but need to face it head on.
CWD is present, needs to be dealt with now and is dire and deadly.
Only immediate action will avoid catastrophic outcomes.
The future of deer and deer hunting is on the line now.