What is CWD?
Chronic wasting disease is a fatal neurological disease found in deer, elk and moose. It belongs to a family of diseases known as transmissible spongiform encephalopathies or prion diseases. The disease attacks the brains of infected deer, elk and moose, causing the animals to become emaciated, display abnormal behavior and incoordination, and eventually die.
Where is the Disease Found?
Chronic wasting disease occurs in free-ranging and captive cervids (members of the “deer” family) in several places in North America, including Colorado. For the most current information on distribution and relative rates of infection by Game Management Unit in Colorado, see the following maps.
For more detailed estimates of infection rates by Data Analysis Unit, see the 2010-2011 Test Results Summary, as well as the CWD Prevalence by DAU for deer, elk, and moose.
Chronic wasting disease belongs to a family of diseases known as transmissible spongiform encephalopathies or prion diseases. Within this family of diseases, there are three predominant variants that affect animals: scrapie, which has been recognized in sheep for more that 200 years; bovine spongiform encephalopathy in cattle (sometimes referred to as "Mad Cow Disease"); and chronic wasting disease in deer, elk and moose. Within this family of diseases, there are also two main variants that affect humans: Creutzfeldt-Jakob Disease, which occurs naturally in about one out of every one million people in Colorado and elsewhere around the world; and variant Creutzfeldt-Jakob Disease, which has been linked to the large-scale outbreak of bovine spongiform encephalopthy in cattle herds in Great Britain. Through that outbreak and the fact that the British consumed nearly 750,000 infected cattle during a 10-year period, approximately 154 humans have died to date after contracting variant Creutzfeldt-Jakob Disease (http://www.cjd.ed.ac.uk/).
Public Health Issues
To date, ongoing investigations by state and federal public health officials have shown no causal relationship between CWD and human health problems, for more information see CWD and Potential Transmission to Humans.
However, the Colorado Department of Public Health and Environment and the CPW advise hunters to take simple precautions (as listed BELOW) when handling deer, elk, or moose carcasses in units where CWD is known to occur. Hunters with concerns about harvesting or consuming an infected animal may choose to submit samples for testing as described below. If you have questions about the precautions, or CWD and public health, contact CDPHE at (303) 692-2700
Simple Precautions Advised
Do not shoot, handle or consume any animal that appears sick; contact the Colorado Parks and Wildlife in Fort Collins at (970) 472-4300 if you see or harvest an animal that appears sick.
Wear rubber gloves when field dressing and processing animals.
Bone out the meat from your animal.
Minimize the handling of brain and spinal tissues, and wash hands and instruments thoroughly after field-dressing.
Wash hands and instruments thoroughly after field dressing is completed.
Avoid consuming brain, spinal cord, eyes, spleen, tonsils, pancreas and lymph nodes of harvested animals. Normal field dressing, coupled with boning out a carcass, will remove most, if not all, of these body parts. Cutting away all fatty tissue will remove remaining lymph nodes.
Do not consume meat or organs from animals known to be infected with CWD.
Knives, saws and cutting table surfaces can be disinfected by soaking in a solution of 50 percent unscented household bleach and 50 percent water for an hour. Thoroughly rinse all utensils in water to remove the bleach. Afterward, allow them to air dry.
What Portions of Deer, Elk, and Moose Should Be Consumed?
Strong evidence suggests that abnormal proteins, called prions, cause chronic wasting disease in deer and elk. Research indicates that the prions naturally accumulate in certain parts of infected animals -- the brain, eyes, spinal cord, lymph nodes, tonsils, pancreas and spleen- relatively early in the course of disease, well before the animal is visibly ill. In later disease stages, abnormal prions also can accumulate in a wider variety of tissues and organs, including kidney, lung, heart, and muscle.
Chronic Wasting Disease Testing
Hunters can find out their test results online using the Test Results database, or by calling their local Area Office or CPW Customer Service at (303) 297-1192. Please have your head submission number ready
For the most recent year's testing information, including guidelines, submission sites, locations and schedules, and a list of species, see Submission Site Information.
Colorado Parks and Wildlife researchers and biologists are studying chronic wasting disease on numerous fronts - addressing wildlife health issues and assisting public health experts and scientists with their ongoing research. Parks and Wildlife personnel’s work and expertise on the subject is noted not only nationally, but internationally as well.
Staff researchers and biologists conduct studies on the disease, and also collaborate and provide funding for studies conducted by other agencies and states. Employees have been involved in the following chronic wasting disease work:
The successful development of improved, more sensitive testing procedures to detect chronic wasting disease in deer, elk and moose.
An ongoing field study designed to measure the relationship between deer density and disease prevalence.
Ongoing research to track the progression of the disease through a deer’s body to better understand how the disease is transmitted and how it can be better diagnosed.
Ongoing studies to determine if chronic wasting disease can be passed to bighorn sheep, mountain lions and other animals.
Specific studies to determine the ability of chronic wasting disease to infect cattle.
Epidemiological studies conducted by state and federal agencies to determine if a link between chronic wasting disease and human neurological disorders exists.
Laboratory studies to assess the potential susceptibility of different animal species, including humans, to chronic wasting disease.
Ongoing monitoring studies to determine geographic distribution and level of prevalence of chronic wasting disease in the state.
Research into early detection methods to diagnose chronic wasting disease in live, healthy-appearing animals.
Studies of deer movement patterns to determine if links between disease prevalence and deer movement exist.
In addition, Parks and Wildlife staff serve nationally as a source of information and resources concerning chronic wasting disease research. To access scientific publications on chronic wasting disease, see CWD Research Articles.
Chronic Wasting Disease Management
The Colorado Park and Wildlife’s disease management efforts are focused on:
Preventing the spread of chronic wasting disease beyond historically infected areas.
Reducing chronic wasting disease prevalence within infected areas by removing deer and elk from diseased herds.
Enforcing illegal feeding regulations and transport laws restricting the movement of deer, elk and moose from infected areas or into the state.
Continuing research in conjunction with other agencies and states to further knowledge to manage affected deer, elk and moose herds.