News » Arkansas Reporter

Upping the game against Chronic Wasting Disease in Arkansas

Game and Fish creates research division.

by

2 comments
A SICK DOE: Deer infected with CWD salivate copiously.
  • A SICK DOE: Deer infected with CWD salivate copiously.

In mid-January 2016, to the delight of visitors to the Ponca Elk Education Center, a healthy-looking white-tailed doe started bedding down in the interpretive garden outside. "When I would walk into work, she was lying there under a sweet gum tree just looking at me," Mary Ann Hicks, manager of the Arkansas Game and Fish Commission facility, said.

It wasn't unusual to see a deer in the garden, which had gone to seed and had plenty of cover. The deer in Ponca, in the Boxley Valley of Newton County, have become used to their human neighbors, feeding in their gardens and sometimes visiting the center, Hicks said. "We thought it was kind of cool," Hicks said. "It had happened before."

But by the end of January, Hicks noticed the deer had lost a lot of weight. "It started walking around on the boardwalks and would look in the window at us. It was really weird," she said. It was also leaving a lot of scat around the center, and the scat did not look normal.

A worker at the center called Hicks on Jan. 29 to tell her that the deer was standing in the creek, drooling, its legs splayed in a wide stance. Game and Fish biologists were summoned, and "by the time they got there, it was standing in the creek with that wide stance, holding its mouth in the water and urinating at the same time," Hicks said.

The biologists wondered if the doe was suffering from bluetongue, a viral disease. Neither they nor the staff at the education center knew that an elk killed a couple of months earlier at Pruitt was infected with the state's first case of chronic wasting disease (CWD); the results from a lab test in Wisconsin had not yet come back to Arkansas.

The doe was found dead a few days later along the creek. Biologists took bits of her brain stem and surrounding lymph nodes and hauled off the carcass. They told Hicks to bag up all the scat she could find, which she did.

In February 2016, the Wisconsin lab confirmed that the elk harvested the previous winter was infected with CWD, a fatal, infectious neurodegenerative illness caused by a misfolded protein called a prion. The deer that died in the creek behind the Elk Education Center was the state's second animal confirmed with CWD.

Since then, 206 deer and six elk have tested positive for CWD. A fatal disease once thought of as a Western illness was now in Arkansas, the first state in the Southeast to detect it.

Some people blame the elk imported into the state in the 1980s for bringing CWD here. But no one really knows how the disease was transmitted. "The point is, now we have it," Game and Fish deer biologist Cory Gray said. "Now we're going to address it. ... We tell people, we need to stay with the science."

Game and Fish had taken steps to guard against CWD, collecting samples from elk since 1997 and in deer since 2003, making it illegal to transport intact carcasses into the state and taking other steps. When the positive result came back, the agency dusted off a 2006 response plan it hoped it would never need, updated it and, after consulting with national experts, decided to establish a new section at the agency: The Research, Evaluation and Compliance Division. Game and Fish asked Gray to manage the division and in January hired the agency's first wildlife veterinarian, Dr. Jenn Ballard, a North Little Rock native who also holds a Ph.D. in veterinary and biomedical science with an emphasis in population health. 

"If there is one good thing that comes out of CWD," Gray said, "it is that we created this new division." CWD won't be its only research, but for now it's the major focus.

Chronic wasting disease first turned up in 1965 in a research facility in Colorado, where sheep infected with scrapie (a neurodegenerative disease) were being kept along with mule deer. The researchers couldn't keep the deer alive; it's thought the prions shed by the sheep had mutated into a form infectious to the mule deer. The CWD prion affects reindeer as well as mule deer, elk and white-tailed deer.

A random harvest last year of 266 deer from a test area roughly 20 miles long and 10 miles wide in Newton County found that 62 deer — 23 percent — had CWD.

When Gray got the results from that harvest, "it was not a happy day," he said. "You spend your whole career managing a resource and investing so much of yourself in that resource, and the commission has implemented regulations ... to prevent [CWD transmission]. And now we've detected it. It's a punch in the gut."

A brain infected with the disease looks like Swiss cheese, riddled with small holes. Other prion diseases include mad cow (bovine spongiform encephalopathy), scrapie (in sheep), Creutzfeld-Jakob (a human variant) and kuru (also a human variant, known from a New Guinea tribe whose members ate the brains of their ancestors).

Prions are scary things: The mad cow outbreak in the 1990s in the United Kingdom was linked to human deaths from Creutzfeld-Jakob; scientists suggested the disease was transmitted by the consumption of tainted beef. The European Union and the United States banned the import of British beef, and Great Britain eventually ordered the slaughter of millions of cows and bulls. Since then, there have been four cases of humans dying from the human variant of mad cow in the United States.

The prion that causes CWD cannot be cooked away or otherwise destroyed. Once it's in the environment, via excrement or urine from infected animals, it's there forever. Game and Fish disposes its infected tissue samples in an incinerator that heats to 1,700 degrees F. But because you can't burn up a prion, ashes from the incinerator are placed in metal containers before being disposed of in landfills.

Which begs the question: If you eat a deer infected with CWD, do you risk getting a prion disease?

It's possible, the Centers for Disease Control says, but undetected as of yet. For now, Gray said, Game and Fish encourages hunters not to consume their venison until samples from the deer or elk come back negative. "That's a personal choice," Gray said. "We try to provide a rapid turnaround" for results, usually seven days.

The new Game and Fish research division will also employ a director, a "human dimensions specialist" to do outreach to the public and social surveys, a biostatistician and research biologists. In 2016, Gray and other Game and Fish staff focused on work to determine disease prevalence and location. They set up stations across the state during modern gun season last year to take samples of harvested animals, and also sampled road kill and "targeted animals" — any animal exhibiting symptoms of the disease. Taxidermists statewide helped with the sampling.

The epicenter of the disease is in Newton County. The CWD Management Zone also includes Boone, Carroll, Johnson, Logan, Madison, Marion, Pope, Searcy and Yell counties. (Inclusion in the zone does not mean that CWD-infected animals have been found; it means that part of the county falls within a 10-mile radius of a diseased animal.) Bag limits within certain zones have been liberalized to reduce the population of possibly infected deer, and Game and Fish has made it illegal to transport deer or elk carcasses out of the CWD Zone except for antlers, cleaned skulls, deboned meat, cleaned teeth, hides or finished taxidermied products. Starting Jan. 1 of this year, Game and Fish made it unlawful statewide to use natural scents or lures containing deer and elk urine or other biofluids.

All elk harvested statewide must be checked so that samples may be taken for CWD testing.

The research division is now gearing up to take genetic samples of elk and deer, both to create a database and to see the relationship between the individual CWD-positive animals. Western state biologists are studying elk DNA to see if they can identify resistant genes.

The division is also partnering with UA Little Rock to survey Arkansas hunters to see if they've changed their hunting practices, whether they're willing to have their animals tested, how far they're willing to drive to do that, and so forth.

Game and Fish is hoping to partner with the Arkansas Livestock and Poultry Commission to be able to use its laboratories to speed up testing.

"This is really where conservation is moving in the future," Dr. Ballard said: Agencies are "recognizing the role that veterinarians play alongside biologists."

Comments (2)

Showing 1-2 of 2

Add a comment
 

Add a comment

Clicky