Mexican Fish Report

ODFW is increasing its monitoring of deer and elk herds for Chronic Wasting Disease (CWD), a fatal neurological disease that has never been detected in Oregon’s cervids but is spreading in North America.

The disease is caused by a protein prion that damages the brain of infected animals, causing progressive loss of body condition. It’s untreatable and always fatal. The prions that cause CWD can also last a long time in the environment, infecting new animals for decades.

ODFW has been keeping an eye out for the disease for years now, running check stations in eastern Oregon to test harvested deer and elk on the opening weekends of popular hunting seasons and requiring disease testing at captive cervid ranches. (The test to confirm CWD involves collecting an animal’s lymph nodes or brain stem and can only be conducted once an animal has died.)

ODFW sampled deer for CWD over opening weekend of rifle deer season. The department will host another two check stations this weekend for Rocky Mountain elk season (Sunday and Monday, Oct. 29 and 30 in Biggs at exit 104 along I-84 and at the ODOT weigh station one mile east of Prineville on Hwy 26). All successful hunters driving by these locations should stop and get their animal tested, which takes just a few minutes.

ODFW is also testing road-killed deer and elk and is expanding this testing to western Oregon this year. Animals that exhibit signs of wasting or neurological disorder are also tested. If you see or harvest a sick deer or elk, report it to the ODFW Wildlife Health Lab number at 866-968-2600 or by email to Wildlife.Health@state.or.us and do not consume the meat.

Although CWD has not been shown to sicken people, the Center for Disease Control advises hunters not to eat meat from animals infected with CWD. It’s also always a good idea to wear latex or rubber gloves when field dressing an animal and to wash hands and instruments thoroughly afterwards.

ODFW is also asking hunters interested in having their deer or elk tested for CWD to contact their local office to set up an appointment. ODFW is most interested in deer and elk that are at least two-years-old (e.g. not spikes). To get an animal CWD tested, hunters will need to bring in the animal’s head, which should be kept cool prior to sampling if possible. ODFW will also take a tooth for aging and hunters should receive a postcard several months later with information about the animal’s age. If an animal tests positive for CWD, the hunter will be notified. (Note that samples are tested out of state and results can take several weeks.)

Hunters heading to a state with CWD are reminded they are prohibited from bringing back any parts of their deer, elk or moose that contain brain matter or spinal cord tissue (see page 29 of Big Game Regulations under “Parts Ban”). This is where the CWD prion is most concentrated.

“CWD is considered one of the most devastating wildlife diseases on the American landscape today,” said Colin Gillin, ODFW State Wildlife Veterinarian. “Once CWD enters a state and infects free-ranging deer and elk, it has been nearly impossible to eradicate with present day tools. So we want to do all we can to keep this disease out of Oregon.”

Once animals show the clinical signs of the CWD, the disease has probably already been on the landscape one or more years. It can take several years for an animal to become ill but the disease can be transmitted throughout the period of the infection.

Early detection of CWD could allow Oregon to potentially eradicate the disease before it takes root. The state of New York was successful in limiting CWD’s spread because it quickly located the first few individual animals infected and removed them, and no further cases were detected.

“If we ever document CWD in Oregon, we want to act quickly and will need the support of Oregon hunters,” Gillin. “Early detection is our best chance to keep the disease from spreading, should it enter the state. That is why we need the active involvement of hunters and all Oregonians to continue surveillance and keep an eye open for animals that appear sick.”

CWD appears to spread most quickly through movement of live animals, although it can also spread by transport of carcasses by hunters or through infected migrating deer and elk. Documented cases of CWD have occurred in Alberta, Arkansas, Colorado, Illinois, Kansas, Maryland, Michigan, Minnesota, Missouri, Montana, Nebraska, New Mexico, New York, North Dakota, Ohio, Oklahoma, Pennsylvania, South Dakota, Texas, Utah, Virginia, West Virginia, Wisconsin, Wyoming, and Saskatchewan.