Frequently Asked Questions About CWD

Chronic Wasting Disease (CWD) poses a serious threat to the health of Michigan's deer and elk populations, both free-ranging and captive, and to their long-term management.  Infection of free-ranging cervid populations may establish long-term foci of infection.  Implications of CWD for free-ranging cervid populations may be dire.

What is CWD?

Where has CWD been found?
Where was the CWD deer in Michigan?
What are the restrictions for hunters importing deer, elk or moose from other states or provinces?
Now that CWD has been found in Michigan, what are the DNR and MDARD doing?
What routine surveillance will occur statewide?
Where can I check the lab results for my wild harvested deer?
Does CWD pose a health risk to humans?
Is the meat safe to eat?
How can CWD be treated and controlled in wildlife?
Why should people outside of the 17 States with known infection care about the disease?
How is CWD transmitted?
Can CWD be transmitted to cattle?
How can you tell if a deer has CWD?
What should I do if I see a deer that shows CWD symptoms?
What are recommended websites? 

What is CWD?
CWD is a neurological (brain and nervous system) disease found in mule deer, white-tailed deer, elk and moose. The disease belongs to a family of diseases known as transmissible spongiform encephalopathies (TSE) or prion diseases. The disease attacks the brains of infected deer and elk and produces small lesions that result in death. While CWD is similar to mad cow disease in cattle and scrapie in sheep, there is no known relationship between CWD and any other TSE of animals or people. For more information on CWD please visit www.michigan.gov/cwd

Where has CWD been found?  Click for a map 

The disease also has been diagnosed in commercial game farms in Colorado, Iowa, Kansas, Michigan, Minnesota, Missouri, Montana, Nebraska, New York, Oklahoma, Pennsylvania, South Dakota, Wisconsin,  Saskatchewan and Alberta, Canada and in an elk herd in Korea. In Michigan, the disease was confirmed on 8/25/2008 in a Kent County deer breeding facility.

The disease was long thought to be limited in the wild to a relatively small endemic area in northeastern Colorado, southeastern Wyoming and southwestern Nebraska, but it has recently been found in new areas of these states, as well as in wild deer and elk in western South Dakota, and wild deer in northern Illinois, south-central New Mexico, northeastern and central Utah, south-central and south-eastern Wisconsin, central New York, Virginia, north-east West Virginia, Kansas, and west and south-central Saskatchewan. Also, a CWD-positive moose has recently been discovered in the endemic area of Colorado. And more recently, Minnesota, Maryland, North Dakota, Missouri, western Texas, and Alberta have been added to the list of states or provinces where the disease has been found in wild deer.

Occurrence of CWD in Wildlife:

Where was the CWD deer in Michigan?
On August 25, 2008, CWD was confirmed in a captive 3-year-old white-tailed doe from a privately-owned cervid facility in Kent County. The owner sent the culled deer to the Michigan Department of Agriculture and Rural Development (MDARD) for required testing.  

What are the restrictions for hunters importing deer, elk or moose? 

2012 Michigan Hunting and Trapping Digest:

Hunters importing harvested free-ranging deer, elk or moose from Colorado, Illinois, Kansas, Maryland, Minnesota, Missouri, Nebraska, New Mexico, New York, North Dakota, South Dakota, Texas, Utah, Virginia, West Virginia, Wisconsin, Wyoming, Alberta, or Saskatchewan are restricted to bringing into Michigan only deboned meat, antlers, antlers attached to skull cap cleaned of all brain and muscle tissue, hides, cleaned of excess tissue or blood, upper canine teeth or a finished taxidermy mount.

If your deer, elk or moose is sampled for CWD testing, wait for the test results before eating the meat. If you are notified by another state or province that a deer, elk or moose you brought into Michigan tested positive for CWD, you must contact the DNR Wildlife Disease Lab within 2 business days (8 a.m. to 5 p.m.) at 517-336-5030 and provide details.

Any changes to important regulations will be posted at www.michigan.gov/cwd
In addition, the US Department of Agriculture may have regulations in importation from Canada. You can contact them at 307-734-3277.

Now that CWD has been found in Michigan, what are the Michigan Department of Natural Resources (DNR) and MDARD doing?
The agencies followed the steps outlined in the 2002 Michigan Surveillance and Response Plan for CWD of Free-ranging and Privately Owned/Captive Cervids and Michigan Surveillance and Response Plan for CWD of Free-ranging and Privately Owned Cervids (Issued August 26, 2002; Revised July 18, 2012) which were developed to address this nationally emerging disease. Since the development of the plan, MDARD and DNR have had a surveillance program in place to detect CWD in captive or wild cervids.

What routine surveillance will occur statewide?

Continued surveillance is needed to determine whether or not CWD currently exists in free-ranging deer or elk in Michigan and its geographic extent, if present.

Surveillance for 2012 calendar year will consist of targeted surveillance only:

Targeted surveillance consists of the continuation of current DNR Wildlife Division activities to identify and test free-ranging cervids (deer, elk, and moose) statewide that have been observed by the public or Wildlife Division staff showing symptoms consistent with CWD (emaciation, abnormal behavior/nervous system symptoms, excessive salivation, etc.)  These animals (whole animal or head) will be collected by Wildlife Division staff and transported to the DNR Wildlife Disease Laboratory (WDL) at Michigan State University for sampling and testing.  Surveillance will take place in all counties in Michigan.  Hunter harvested deer or elk will not be tested for CWD in 2012.  Only those deer, elk or moose exhibiting neurological symptoms will be tested.

Testing Procedures:

• Heads of deer will be collected by Wildlife Division staff, uniquely identified with a numbered jaw tag and transported to the DNR WDL for testing.
• Removal of a medial retropharyngeal lymph node (MRLN) from the head at the DNR WDL.  ELISA testing for CWD will be done at Michigan State University's (MSU) Diagnostic Center for Population and Animal Health.
• Data from each animal's jaw tag (e.g., number, age, sex, geographic location of sampling to the section level and hunter contact information) will be scanned and recorded in a computerized database housed at the DNR WDL.
• Suspect samples will be further tested with immunohistochemistry (IHC).
• Test results along with their deer's lab age on-line at www.michigan.gov/dnrlab or by calling the Wildlife Disease Lab (517-336-5030).  If the test result is suspect, the hunter will be notified by phone and by mail, with another letter mailed with the final results, whether negative or positive. 

Does CWD pose a health risk to humans?
CWD has never been shown to cause illness in humans. For more than two decades, CWD has been present in wild populations of mule deer and elk in Colorado. During this time, there has been no known occurrence of a human contracting any disease from eating CWD-infected meat. However, public health officials recommend that people not consume meat from deer that test CWD-positive. Some simple precautions should be taken when field dressing deer:

• Wear rubber gloves when field dressing your deer.
• Bone out the meat from your deer.
• Minimize the handling of brain and spinal tissues.
• Wash hands and instruments thoroughly after field dressing is completed.
• Avoid consuming brain, spinal cord, eyes, spleen, tonsils and lymph nodes of harvested animals. (Normal field dressing coupled with boning out of a carcass will essentially remove all of these parts.)
• Request that your animal is processed individually, without meat from other animals being added to meat from your animal.

Is the meat safe to eat?
The agent that produces chronic wasting disease in deer and elk is an abnormally shaped protein, called a prion. Research completed to date indicates that the prions accumulate in certain parts of infected animals - the brain, eyes, spinal cord, lymph nodes, tonsils and spleen. Based on these findings, it is recommended that hunters not eat meat from animals known to be infected with CWD. Hunters in CWD areas are also advised to bone out their meat and to not consume those parts where prions are likely to accumulate.

How can CWD be treated and controlled in wildlife?
There is no treatment for CWD; it is fatal in all cases to the members of the deer family that it infects. CWD transmission can be controlled by limiting contact between infected and non-infected animals.
The DNR and the MDARD are working to maintain the integrity of Michigan's white-tailed deer and elk herds. Surveillance continues to be the key to CWD control.

Why should people outside of the 17 States (see table above) with known infections in wild deer or elk care about the disease?

While the long-term effects on the dynamics of these populations are not yet known with certainty, modeling, research and surveillance in Colorado and Wyoming suggest they could be dramatically negative.  Surveillance and control programs necessitated by CWD are demanding of both monetary and personnel resources of wildlife management agencies, which are often quite limited.  Perhaps most ominously, public and agency concerns about potential human health risks associated with CWD, while thus far groundless, may nevertheless undermine participation in hunting, with potentially marked effects on local and state economies, habitat degradation, and the ability of wildlife agencies to manage free-ranging cervid herds.

A healthy white-tailed deer population in Michigan is important. Chronic wasting disease is a statewide issue for the following reasons:

• Chronic wasting disease can spread through the deer herd.
• All deer infected with CWD die from the disease.
• White-tailed deer are native to Michigan and it is important to preserve our native wildlife.
  
  
• Any regional threat to a healthy deer population is a statewide concern.
• A healthy deer herd is important for hunting traditions. Michigan has more than 725,000 deer hunters who have harvested an average of 450,000 deer annually during the past decade. Deer hunting contributes more than 10 million days of recreation every year.
• Deer hunting annually generates more than $500 million dollars impact to the state's economy. A healthy deer herd is critical to the state's economy.
• Without appropriate management in Kent Co., the disease may spread to other areas of the state.

How is CWD transmitted?
CWD is transmitted between deer via saliva, feces and urine, as well as indirectly through soil or food contaminated by the saliva, feces or urine of an infected animal. CWD prions can remain infectious for years in certain types of soil.

Can CWD be transmitted to cattle?
To date, there has been no documented occurrence of cattle contracting CWD from free-ranging deer or elk. Further, in long-term studies where cattle have been housed in pens with CWD-infected deer and elk, transmission has not occurred. In studies where cattle had CWD-positive material injected directly into their brain, many of the cattle developed CWD. These experiments show that cattle can potentially be infected with CWD, but only through a very unlikely and extreme route of exposure. In experiments where cattle were fed brain material from CWD-infected deer and elk, all animals have remained healthy. Because animals are infected with CWD by the oral route, this experiment simulates a more natural route of exposure.

How can you tell if a deer has CWD? 
Infected animals may not show any symptoms of the disease for years. In the later stages of the disease, however, infected animals begin to lose bodily functions and display abnormal behavior such as staggering or standing with very poor posture. Animals may have an exaggerated wide posture, or may carry the head and ears lowered. Infected animals become very emaciated (thus wasting disease) and will appear in very poor body condition. Infected animals also will often stand near water and will consume large amounts of water. Drooling or excessive salivation may be apparent. Note that these symptoms may also be characteristic of diseases other than CWD.

What should I do if I see a deer that shows CWD symptoms?
You should accurately document the location of the animal and immediately and call the RAP Line (1-800-292-7800). Do not attempt to contact, disturb, kill, or remove the animal.

What are recommended websites?
For more information about how Michigan is working to prevent CWD from infecting Michigan's wild cervid populations and control CWD in deer and elk facilities, see the Emerging Diseases Web site at www.michigan.gov/cwd, or visit the DNR's website on wildlife diseases at www.michigan.gov/wildlifedisease
For national information on CWD, visit www.cwd-info.org