MDC reports 33 CWD positives out of nearly 24,500 samples tested

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JEFFERSON CITY, Mo. – The Missouri Department of Conservation (MDC) reports 33 new cases of chronic wasting disease (CWD) have been found following the testing of 24,486 free-ranging Missouri deer through its 2017-2018 sampling and testing efforts. The new cases were from the following counties:

  • Adair: 3
  • Cedar: 1
  • Franklin: 4
  • Jefferson: 1
  • Linn: 7
  • Macon: 3
  • Perry: 1
  • Polk: 3
  • St. Clair: 4
  • Ste. Genevieve: 6

Of the 33 new cases, 16 were from hunter-harvested deer, one was from a road-killed deer, and 16 were from MDC’s post-season targeted culling efforts in the immediate areas around where previous cases have been found.

This year’s findings bring the total number of free-ranging deer in Missouri confirmed to have CWD to 75. For more information, visit under “CWD in Missouri.”

“For a third year in a row, we found no CWD-positive deer in central Missouri, where a single case was confirmed in early 2015,” said MDC Wildlife Disease Coordinator Jasmine Batten. “Additionally, we found no cases of CWD on the Missouri-Arkansas border, despite the high level of CWD in northwest Arkansas.”

Batten added that where CWD has been found in Missouri, the numbers of positives remain relatively low.

“It is encouraging that cases of CWD are still pretty low overall, and MDC remains committed to monitoring the disease and taking actions to limit its spread,” she said. “We encourage hunters and landowners to continue participating in our CWD monitoring and management efforts.”

Batten added that these efforts are vital in limiting the spread of the disease.

“If we do nothing, areas affected by CWD will increase in size and many more deer will become infected by the disease,” she explained. “Over time, this would lead to significant long-term population declines.”

MDC will continue CWD sampling this fall and winter

MDC will again require mandatory sampling of deer harvested during the opening weekend of the fall firearms deer season, Nov. 10 and 11, in and around counties where the disease has been recently found. MDC will again also offer voluntary CWD sampling during the entire fall and winter hunting season of deer harvested in and around counties where the disease has been recently found.

The Centers for Disease Control and Prevention recommend hunters in areas known to have CWD test their deer before consuming the meat.

More information on specific counties, sampling locations, and requirements will be published in MDC’s “2018 Fall Deer & Turkey Hunting Regulations and Information” booklet, and online at, starting in July.

More on targeted culling

After the close of deer season, MDC staff work with landowners on a voluntary basis to cull additional deer within an area of 1 to 5 miles of where recent cases of CWD have been found. Collecting additional samples helps MDC scientists better understand how many deer in the area may be infected and where they are in the area. Targeted culling also helps limit the spread of CWD by removing potentially infected deer from an area.

“Targeted culling has proven to be very useful in finding cases of CWD and in reducing the spread of the disease by removing additional CWD-infected animals,” explained Batten. “We found about half of the new CWD cases this year through targeted culling. Without targeted culling, those 16 infected deer would have continued to spread the disease.”

She added that targeted culling is the only tested method of slowing the growth of CWD in a local deer population.

“The state of Illinois has been successful in stabilizing levels of CWD through the use of a sustained targeted culling program over many years,” Batten said. “In contrast, states such as Wisconsin that have not used targeted culling, or that have only implemented targeted culling for a short period of time, have seen levels of CWD climb steadily.”

Of the more than 101,000 deer MDC has tested for CWD since 2001, about 4,500 have been harvested through targeted culling, including 1,485 from the past season.

“This accounts for about 4% of all CWD samples collected so far, but has resulted in finding about 49% of CWD cases in Missouri,” Batten explained.

Learn more about targeted culling through this video:

For more information on CWD, visit