Chronic Wasting Disease, or CWD, was first discovered in the United States in 1967 in captive mule deer in Colorado.
Since then CWD has been found in Missouri, Illinois and 20 other states and several Canadian provinces. These include Colorado, Illinois, Iowa, Kansas, Maryland, Michigan, Minnesota, Montana Nebraska, New Mexico, Missouri, New York, North Dakota, Oklahoma, Pennsylvania, South Dakota, Texas, Utah, Virginia, West Virginia, Wisconsin, Wyoming, and Alberta and Saskatchewan.
CWD was first discovered in Missouri in 2010 in captive deer on private hunting preserves in Linn and Macon counties. But the Missouri Department of Conservation had begun statewide CWD surveillance of free-ranging deer in 2001 when the deadly disease began spreading through nearby states.
Since that time the MDC has tested more than 100,000 free-ranging deer. Deer are sampled during the opening weekend of fall firearms deer hunting season in targeted counties based on the findings from the previous year.
During the 2017-2018 deer seasons period the MDC tested nearly 24,500 deer for CWD and found 33 new cases for a total of 75 cases in Missouri.
The CWD Management Zone includes counties within approximately 25 miles of CWD detections.
The zone includes these counties within or that touch a radius of approximately 25 miles from where the disease has been found: Adair, Barry, Benton, Bollinger, Boone, Callaway, Cape Girardeau, Carroll, Cedar, Chariton, Cole, Cooper, Crawford, Dade, Franklin, Gasconade, Grundy, Hickory, Jefferson, Knox, Linn, Livingston, Macon, Madison, Mercer, McDonald, Miller, Moniteau, Morgan, Osage, Ozark, Perry, Polk, Putnam, Randolph, Schuyler, Scotland, Shelby, St. Charles, St. Clair, St. Francois, Ste. Genevieve, St. Louis, Stone, Sullivan, Taney, Warren, and Washington.
Hunters who harvest deer in certain CWD Management Zone counties on Nov. 10-11 of this year, the opening weekend of fall firearms deer season, must present their deer, or the head with at least six inches of the neck in place, to an MDC CWD sampling location on the day of harvest. The testing is free and hunters can also get free results.
A complete list, with interactive map, of sampling stations can be found at: https://huntfish.mdc.mo.gov/hunting-trapping/wildlife-diseases/chronic-wasting-disease-cwd/mandatory-cwd-sampling-2018.
In addition, the MDC is offering free CWD sampling and testing of deer harvested anywhere in the state throughout the entire deer hunting season – Sept. 15 through Jan. 15, 2019 – with several sampling locations including MDC offices. The sampling is voluntary and hunters can also get free test results for their deer.
Hunters can have their deer sampled at 11 select MDC offices around the state. Hunters can also take their deer to 64 participating taxidermists and meat processors located in the 48 counties of MDC’s CWD Management Zone.
MDC asks hunters to Telecheck their deer before taking them to a CWD sampling location. Hunters can bring the entire deer – preferably field dressed – or the head with at least 6 inches of the neck in place. Heads that have the cape removed for taxidermy can also be sampled.
CWD test results can take up to four weeks from the time of sample submission. Hunters can get test results for their CWD-sampled deer online at mdc.mo.gov/CWDTestResults.
Of the 33 new cases identified in the past year, 16 were from hunter-harvested deer, 1 was from a road-killed deer, and 16 were found through post-season targeted culling.
Also, more than 200 cases of CWD have been found in deer and elk in northwest Arkansas since early 2016. This has prompted MDC to increase CWD surveillance efforts in southwest Missouri. The good news is, to date no deer from counties bordering Arkansas have tested positive for the disease.
So what is Missouri doing to combat the spread of CWD?
The agency works with hunters, landowners, taxidermists, and others through mandatory and voluntary sampling to collect tissue samples for CWD testing in areas where CWD has been found.
The state agency has removed the antler-point restriction for counties in the CWD Management Zone because young bucks can spread the disease to new areas as they search for territory and mates.
MDC allows the use of two firearms antlerless permits in counties in the CWD Management Zone to help prevent undesired population increases in local deer numbers.
Furthermore, the conservation agency has restricted feeding deer and placing minerals for deer in counties of the CWD Management Zone. Experts also strongly discourage the removal of deer carcasses from counties in the CWD Management Zone, and encourages people to report sick deer to local staff.
According to the Illinois Department of Natural Resources, CWD was first found in northwest Boone County in northern Illinois in the fall of 2002. Since that time more than 100,000 deer have been tested in order to accurately identify where the disease occurs and how severe it is.
CWD has been found in 17 Illinois counties (Boone, Carroll, DeKalb, DuPage, Grundy, JoDaviess, Kane, Kankakee, Kendall, Lake, LaSalle, Livingston, McHenry, Ogle, Stephenson, Will, Winnebago).
Illinois conservation officials have utilized trained agency sharpshooters to help reduce deer populations in known CWD areas in an effort to slow the spread of the disease. Additionally, they’ve managed hunter harvest pressure through season and limits to help control numbers.
According to IDNR, as of June 30, 2017 the department has sampled at least 105,836 deer, with 685 confirmed CWD cases. “While overall prevalence remains low in JoDaviess and Stephenson counties, disease is firmly established and appears to be worsening, accounting for 21 out of 75 (28%) of all positives identified this year. Prevalence is somewhat higher in some eastern counties of the range, but deer populations in those areas are smaller and habitat much more fragmented.”
Most recently CWD testing has been done at the University of Illinois’ Veterinary Diagnostic Laboratory in Urbana, Illinois.
A report from IDNR states, “In order to manage deer densities at the county level, IDNR has liberalized hunting regulations in the northern Illinois CWD area, using virtually unlimited gun permit quotas, a special CWD management hunting season with reduced-price permits, and more days of hunting.
“These changes have not resulted in increased levels of deer harvest. Illinois DNR supplements hunter harvest with agency sharpshooting after the hunting seasons to allow a focused removal of deer from areas in which CWD is known to occur. Sharpshooting occurs on both private and public property through a network of cooperating landowners with a concern for natural resource management.
“Addressing disease control in this fashion at the local level actually allows us to more effectively fight CWD without drastically reducing deer populations throughout the entire county, as would be the case if we were forced to use hunting as the only tool for disease control. Our goal is to suppress CWD prevalence rates so that they remain very low, and to slow the spread of the disease to the remainder of the state.
“Our approach to CWD management impacts CWD dynamics by increasing removal of CWD-positive deer from the population, by reducing contact rates between sick and susceptible individuals, and by reducing the rate of environmental contamination.