KEN PERROTTE: Chronic Wasting Disease afflicting Virginia's deer population

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VIRGINIA IS readying an outreach campaign related to Chronic Wasting Disease this fall. According to Virginia Department of Game and Inland Fisheries Veterinarian Dr. Megan Kirchgessner, a blog will be published soon on the agency website and new CWD flyers and brochures will be available.

Virginia is one of the 25 states and four Canadian provinces with documented cases of CWD. Mississippi is the latest, with one deer confirmed earlier this year. Most of Virginia’s sick deer were killed in Frederick County, with a couple more in Shenandoah County, adjacent to the West Virginia panhandle. The illness was thought to have spread from a captive deer facility in West Virginia.

Thirty-eight sick deer have been documented since CWD was discovered in Virginia in 2009. Sixteen of those were recorded last year.

Many Virginia hunters are aware of hemorrhagic disease, both the bluetongue and epizootic variants. Our regional deer have been hit with hemorrhagic disease multiple times in recent years.

Deer with hemorrhagic disease often die within a couple weeks of exposure. The intensely feverish deer are often found near water. But, the disease isn’t always fatal; some deer survive. And, research shows whitetails can develop some immunity to it.

Then there is CWD, which is always fatal. While hemorrhagic disease is transmitted only by biting midges (gnats), CWD can spread deer-to-deer, with deer being infectious for up to two years before showing symptoms.

Virginia has a “CWD Containment Area” where mandatory sampling requirements, liberalized bag limits and seasons, and carcass movement restrictions are in place. That area includes all of Frederick, Clarke, Shenandoah and Warren Counties. Virginia is also beginning a statewide CWD surveillance program in cooperation with nearly 60 taxidermists,

Lindsay Thomas Jr., communications director for the Quality Deer Management Association, says containment areas are important. The goal is to isolate the disease. The goal is to not allow the disease-causing prions, which are basically misshapen proteins that eventually erode a deer’s brain, to find their way to new areas.

Why is this critical? These prions are insidious, able to survive being frozen or cooked (unless incinerated at incredibly hot temperatures). Research shows prions can survive in soils for years and even be taken up by plants later eaten by deer.

While there are no known transmissions of CWD to humans, related diseases, such as “Mad Cow,” can jump species. Recent research also showed a species of monkey genetically similar to humans could become infected with CWD.

Virginia hunters killing deer in the containment area on the first two Saturdays of general firearms season must take their deer to a CWD Check Station for tissue sample collection. Hunters killing deer on other days of the season and wanting to have the animal tested can drop off the head at any of five VDGIF refrigerator drop-points. Test results are available 3-4 weeks after collection.

Kirchgessner said hunters in the containment area should get all deer tested throughout the entire season. “Hunters can drop off deer’s head and 4 inches of neck and we’ll submit it for testing free of charge. Refrigerators are checked weekly,” she said.

She noted that DGIF has neither the staff nor budget to conduct mandatory testing all season. “Although some agencies take this route, they typically have a much shorter deer season, and larger staff numbers and budgets,” Kirchgessner said.

Thomas noted that just 8 percent of counties with deer nationwide are impacted by CWD. “Hunters must play a key role in keeping deer in those other 92 percent of counties safe,” Thomas said. This includes scrupulously following carcass movement regulations, which often include restrictions such as only removing boned-out, wrapped meat, finished taxidermy products, completely clean hides or capes, antlers, and skull plates with no tissue or brain matter attached.

The disease can explode in exponential fashion. Thomas shared data from Wisconsin showing more than 32,000 whitetails were killed by hunters during the 2016-2017 season in Dane, Iowa, Richland and Sauk counties, the region with the highest incidence of CWD in the state. Hunters from 49 states killed deer there that season. Wisconsin only tested 7 percent of those deer. Seventeen percent were positive for CWD. This means more than 29,000 deer in this CWD hotbed weren’t tested, which also means another 5,000 or so of those deer might also have been positive. How many of those deer and infected body parts ended up in other parts of the country?

Research shows mature bucks are the biggest carriers of CWD, infected at three to four times the rate of does and fawns. Mature bucks spread CWD during the rut, roaming far, creating licking branches, having nose-to-nose contact, fighting and more. Small areas designed to attract deer, such as mineral licks or feeding stations can also facilitate disease spread.

Thomas said, “QDMA believes it’s okay if hunters in CWD areas want to continue protecting yearling bucks to maintain their interest and engagement with hunting through QDM, but we urge them to increase harvest pressure on all bucks 3.5 years and older.”

Thomas said it’s important to report sick deer, especially when they’re encountered outside of a known CWD area. He said he has heard of some hunters advising friends and hunt clubs to do just the opposite, saying that a sick deer report will cause the state wildlife agency to come in and start eradicating deer.

It is true that thinning and aggressive sampling to assess the full extent of the problem is likely when CWD is discovered, but not reporting sick deer is “wrong and irresponsible,” Thomas said. “If you find it early enough, you might be able to stop it; once it’s established in a herd, it becomes very difficult,” he added.

“Hunters need to become educated about CWD. Share information and alerts with friends and fellow hunters. Trust me, you don’t want this in your area,” Thomas said.For specific Virginia regulations and refrigerated drop-off points, see dgif.virginia.gov/wildlife/diseases/cwd. See the new DGIF’s new flyers and brochures at Ken Perrotte’s weblog, outdoorsrambler.com.

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