Chronic Wasting Disease (CWD): Should Rappahannock residents be worried?

‘CWD may pose a risk to people and . . . it is important to prevent human exposures’

‘Containment area’ includes neighboring Warren County

While Chronic Wasting Disease, a fatal neurological disorder of deer, elk, and moose, has only recently gained national attention given new concerns it could potentially spread to people and pets, the state of Virginia for ten years has actively tracked and restricted CWD since it first appeared near Rappahannock County.

One of several Chronic Wasting Disease (CWD) checkpoint stations for deer hunters in Virginia. Photo by Virginia DGIF

In 2009, the Virginia Department of Game and Inland Fisheries (DGIF) established a “CWD Containment Area” — expanded of late to include Warren County — imposing deer and carcass movement restrictions and mandatory sampling requirements. The containment area includes all of Warren, Clarke, Shenandoah and Frederick counties, the latter’s county seat of Winchester and its surroundings “ground zero” for CWD cases in Virginia.

So far, in fact, CWD in Virginia has been confined to the four counties north of Rappahannock.

Reached for this article, DGIF spokesperson Paige Pearson provided figures showing that in 2018 alone CWD was confirmed in 26 deer in Frederick County and two in Shenandoah County, 26 of the deer harvested by hunters showing “no symptoms of the disease.”

From 2009 through September 2018, DGIF diagnosed 39 positive cases of CWD. Given the 28 cases discovered just in 2018, the disease appears to be expanding. These figures do not include ongoing testing from the 2018-19 deer hunting season that ended in January. The 2018-19 results — consisting of over 1,300 deer tested in the containment area — should be available in March, Pearson said.

Beyond the containment area, DGIF is working with statewide taxidermists to collect a large number of samples from regions of Virginia where CWD hasn’t been detected.

The testing, says DGIF, is especially important “because deer infected with CWD can take several years to display symptoms but are infectious and may spread the disease to healthy deer even when they do not appear sick” — as found to be the case this past year in northern Virginia.

The big question now is whether eating venison infected with CWD is dangerous to humans?

In October 2018, the CDC stated: “To date, there is no strong evidence for the occurence of CWD in people, and it is not known if people can get infected with CWD prions. Nevertheless . . . experimental studies raise the concern that CWD may pose a risk to people and suggest that it is important to prevent human exposures to CWD.”

Prions are abnormal infectious proteins that cause CWD, and pass between deer through saliva, feces, urine, and through water or contaminated soil.

According to the CDC, once introduced into an area or farm the CWD prions are highly contagious within the deer population “and can spread quickly. Experts believe CWD prions can remain in the environment for a long time, so other animals can contract CWD . . . even after an infected deer . . . has died.”

Might that include dogs and cats — or even people?

The CWD prion has been shown to infect squirrel monkeys and laboratory mice that carry some human genes, according to the CDC. Scientists showed that CWD was transmitted to monkeys fed infected meat (muscle tissue) or brain tissue from CWD-infected deer.

While there is no strong evidence that CWD is capable of infecting humans or domestic animals, “the CDC has always recommended that people discard venison harvested from known CWD-infected animals rather than continue to eat it,” advises the DGIF.

As for recent deer harvests, DGIF recommended that “wrapped venison butchered from individual deer be uniquely marked on the outside of the package so that if a deer tests positive, venison from that particular animal can be identified and removed from a freezer. It is important to note that the currently available CWD diagnostic tests are not food safety tests and the intent of any testing is not to certify a deer as ‘safe for consumption.’”

Also beware that in the early stages of infection the prions may not be at levels detectable by current testing in Virginia. So a negative test result does not guarantee that an individual animal is not infected with CWD.

About John McCaslin 448 Articles
John McCaslin is the editor of the Rappahannock News. Email him at editor@rappnews.com.