States Confront the Spread of a Deadly Disease in Deer

The creation of  CWD – a  new wildlife disease – in a Colorado experimental station, and its subsequent spread, proves the adage that “Industrial agronomic principles applied to ecological systems will almost always cause harm.”

NOTE: this article is from the NYTimes.com, and was published on January 8th, 2018. The author is Jim Robbins. Image credits are below the photo. Feature photo is via Unsplash.com, with usage rights adhered to.

JOLIET, Mont. — As darkness closed in, one hunter after another stopped at this newly opened game check station, deer carcasses loaded in the beds of their pickups.

They had been given licenses for a special hunt, and others would follow. Jessica Goosmann, a wildlife technician with Montana’s Fish, Wildlife & Parks Department, stepped outside to greet them, reaching for the neck of each freshly killed deer to cut an incision and remove a lymph node for testing.

On the edge of this south-central Montana village, where deer hunting is a way of life, the game check station has become the front line of the state’s efforts to stop the spread of a deadly infection known as chronic wasting disease.

It has ravaged deer herds throughout the United States and Canada and forced the killing of thousands of infected animals in 24 states and three Canadian provinces. It has also been found in Norway and South Korea. With the disease widespread in Wyoming, the Dakotas and the province of Alberta, Montana officials had been bracing for its emergence.

So in November, when biologists discovered it in six deer in this part of Montana and in another near the Canadian border, officials began setting up special hunts and stations for testing.

“It wasn’t a surprise that we found it,” said John Vore, game management bureau chief for the Montana Department of Fish, Wildlife & Parks. “It was a disappointment, but not a surprise.”

On Friday, the department announced that two more deer from this region, taken early in the special hunt, tested positive for the disease. Other test results are pending.

Chronic wasting disease is a contagious neurological disease that infects elk, deer, moose and caribou, and reduces their brains to a spongy consistency. Animals become emaciated, behave strangely and eventually die. It’s not known to be transferred to humans. Neither is it known to be spread from wild to domestic animals. There is no treatment, although a vaccine has been successful in tests in wild deer.

It is among a class of diseases known as transmissible spongiform encephalopathy, or TSE. Most experts believe the infectious agent is something called a prion, a misfolded cellular protein found in the nervous system and lymph tissue. The disease was first noted in captive deer in Colorado in the 1960s. The most closely related animal disease is scrapie in sheep.

“It’s a very unusual disease,” said Matthew Dunfee, an expert at the Wildlife Management Institute in Fort Collins, Co. and project director for the Chronic Wasting Disease Alliance. “Some experts say it’s a disease from outer space.”

The emergence of chronic wasting disease here is a blow to Montana, which prides itself on world-class deer and elk hunting and where many people hunt both animals for subsistence. It has renewed a dispute over how Wyoming manages its elk, and sparked fears that the epidemic could grow much worse, even spreading into the vast wildlife herds of Yellowstone National Park, with which the states share a border.

Montana will have to begin decades of surveillance in hopes of keeping the disease from spreading. Senator Jon Tester, Democrat of Montana, and Representative Ron Kind, Democrat of Wisconsin, have both introduced legislation to provide funding for states hit by the disease.

If the disease prevalence is higher than 5 percent of the deer population, the state will step up its efforts to find and remove infected deer. “That could be increasing the harvest of bucks because bucks are two to three times more likely to be infected and to spread the infection,” Mr. Vore said. “If there are hot spots within the broader area with high prevalence, we can go in and address deer density in those hot spots. If we have large aggregations of deer in an alfalfa field, for example, we want to address that.”

If it’s under 5 percent, officials will continue to monitor hunters the way they are now and not do more aggressive culling.

Hunters here are concerned, but waiting to see what happens. “Between deer and elk, all I eat is wild game,” said Brodie McDonald, an electrician in Laurel, Mont., who brought his white tail buck in the back of a truck here to be tested. “If it comes back positive I won’t eat it, but if it’s negative I will,” he said. “It worries me that it might become more widespread and you have to get every deer you shoot tested.”

The lymph nodes taken from the check station are tested at a lab in Fort Collins, Colo. Ms. Goosmann said hunters are notified if positive tests are confirmed, and should throw out the meat.

And those who hunt in areas where the disease is known to occur should bone out their meat and not consume the brain, spine or lymph nodes, experts said.

Though chronic wasting disease has not been detected in the vast herds of elk, or in deer and moose in Yellowstone, officials are worried it will find its way into the park and diminish the size of the herds.

Ben Bailey, right, getting ready to remove the lymph nodes of a deer brought in. Lynn Donaldson for The New York Times
Wyoming has had infected deer and elk since 1985, the disease now present in 21 of 23 counties. Experts say mule deer can decline by up to 20 percent a year and localized extinction of some herds is possible.

Mr. Vore said Montana will move aggressively to eradicate the disease by culling deer. “In some states it has decreased animal populations by 40 percent,” he said. “We want elk and deer to be around for our kids and grandkids for everybody to enjoy 20 and 30 years from now.”

New York is the only state that has apparently been able to eliminate the disease through the culling of infected populations when first detected. Many states without the disease ban hunters from bringing in parts of the carcasses of deer they have killed in states with existing infections.

Wyoming has become a center of concern for many biologists, who warn that the way that it manages its elk herds could exacerbate the spread of the disease should the infections turn up in feeding grounds.

There are 22 state elk feed grounds and one federal feed ground, the National Elk Refuge, next to Jackson, Wyo., that feed elk in the winter to keep them from eating hay on ranches. The feeding concentrates the elk by the hundreds and thousands, a recipe for magnifying the incidence of disease, and spreading it, biologists say. The prions are believed passed through waste and saliva.

In a letter to Keith Culver, president of the Wyoming Game and Fish Commission, Dan Vermillion, chairman of Montana’s Fish & Wildlife Commission, requested an end to the controversial practice. If not “we will all be culpable in leaving a greatly devalued landscape to future generations,” he wrote. “As your neighbor, we ask you to begin the process of closing these feed grounds.”

Mr. Culver said the state had no plans to close the grounds. “We continue to look at ways to improve management of feed grounds,” he said, noting that the disease has never been found in them and even if it were, it might not exacerbate the infection rates. “Elk are a herd animal and tend to congregate anyway.”

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A version of this article appears in print on January 9, 2018, on Page D6 of the New York edition with the headline: States Confront Spread of Deadly Illness in Deer.