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Deadly CWD Reaches Outskirts Of Bozeman

Montana confirms dreaded cousin of Mad Cow detected in Gallatin, Paradise and northern Madison deer. Wyoming, meanwhile, will keep feedgrounds open


Chronic Wasting Disease is no longer out of sight and mind for residents of America's fastest-growing micropolitan area with the announcement that a CWD-infected deer was confirmed in the Gallatin Valley just beyond Bozeman's back door.  Photo by Todd Wilkinson
Chronic Wasting Disease is no longer out of sight and mind for residents of America's fastest-growing micropolitan area with the announcement that a CWD-infected deer was confirmed in the Gallatin Valley just beyond Bozeman's back door. Photo by Todd Wilkinson

By Todd Wilkinson

Deadly, always-fatal and much feared Chronic Wasting Disease has now been confirmed in deer roaming both the Gallatin and Paradise valleys—and state wildlife officials are also concerned about a major emerging hotspot for disease along the lower Ruby River.

The arrival of CWD in big game animals around southwest Montana, a prominent part of the Greater Yellowstone Ecosystem, is certain to cause many to wonder how widespread the illness, which strikes members of the deer family (deer, elk, moose and caribou), might now actually be.

The fact that an infected white-tailed deer was killed by a hunter within sight of the suburbs of Bozeman is certain to elevate public concern to a whole new level.

During the first week of December, Montana Fish Wildlife and Parks revealed that five new hunt areas had notched CWD positives for the first time. Their locations are the Gallatin, Paradise and northern Madison valleys east of the Tobacco Roots, as well as an area in the lower Missouri Breaks near Wolf Point and a hunt unit in Beaverhead and Madison counties.

The revelation of greatest immediate worry, officials say, is a cluster of CWD involving whitetails along the lower Ruby River near Sheridan. There, Montana’s wildlife agency collected 335 tissue samples from dead deer taken in Hunting District 322 and 78 of those, to date, have tested positive. That’s a percentage far above the norm.

To try to slow the infection rate, the state is carrying out a supplemental post-season hunt to knock down whitetail numbers and get a larger sampling size to better gauge CWD’s presence there. Reducing ungulate numbers and preventing large concentrations of animals on winter ranges is part of the state’s strategy for confronting the disease.

CWD was first confirmed in free-ranging big game animals in the state in 2017 with a mule deer shot south of Billings not far from Montana’s border with Wyoming. Since then, 343 tests from more than 16,000 samples have come back positive. The breakdown is 222 whitetails, 118 mule deer, one elk and two moose statewide.

However, the disease first raised alarm bells earlier when it was detected in captive game farms in Montana in 1999 and again this year. (Operating new game farms is forbidden in the state and those still in existence were grandfathered following passage of a citizen initiative).

Montana’s wildlife department spokesman Greg Lemon noted that during 2004 and 2005 Montana made a serious attempt, using federal money, to test harvested big game animals across the state but CWD then was never confirmed. “We looked as hard as we could but didn’t find it,” he said. Wildlife vets tested animals around Phillipsburg where game farm animals had escaped from holding pens, but they too turned up negative.
Latest CWD prevalence map in Montana showing the disease has reached the four corners of the state. Experts say people should expect that it also exists everywhere in-between. While only recently confirmed in 2017, it seems to have spread quickly or has testing only confirmed what's been here for awhile. Graphic courtesy Montana FWP
Latest CWD prevalence map in Montana showing the disease has reached the four corners of the state. Experts say people should expect that it also exists everywhere in-between. While only recently confirmed in 2017, it seems to have spread quickly or has testing only confirmed what's been here for awhile. Graphic courtesy Montana FWP
All four deer-family species found in Wyoming have also tested CWD positive with deer infections being far more prevalent than elk. CWD arrived in Wyoming in mule deer in the southeastern corner of the state in 1985 followed by a CWD-positive elk a year later.  Since then it has fanned out in all directions, putting it on collision course with the Greater Yellowstone Ecosystem—a region with Yellowstone Park at its heart, known for having the most diverse and healthy concentrations of big game animals in the Lower 48.

Idaho, also a state that forms part of Greater Yellowstone, has so far not officially confirmed any cases of CWD though experts say its arrival there too is inevitable.

CWD originated in Colorado at a wildlife research lab in the late 1960s and now is found in wildlife in more than two dozen states. Classified as a “prion disease,” CWD is a cousin to notorious Mad Cow Disease that decades ago infected cattle and people in the UK. More technically, CWD is grouped among a category of prion illnesses known as transmissible spongiform ecephalopathies (TSEs), and it shares company with  bovine spongiform encephalopathy (BSE) more commonly known as Mad Cow disease, scrapie in sheep, and variant Creutzfeldt-Jakob disease (vCJD) in humans, and others.

Prions are not normal living pathogens like bacteria and viruses but comprised of hardy misshapen proteins that attack the brain and central nervous system of hosts, causing debilitating impacts similar to severe dementia in humans. Afflicted animals in the final stages of life are often thin and gaunt, staggering, foaming at the mouth and appear to have an unquenchable thirst for water. A fair number, dazed and confused, are struck by cars.
A map prepared by the US Geological Survey, updated Dec. 1, 2020, showing the presence of CWD in the US and Canada in wild wildlife populations and animals at captive game farms. Soon, the disease is expected to reach Arizona, Nevada and the three states on the West Coast.
A map prepared by the US Geological Survey, updated Dec. 1, 2020, showing the presence of CWD in the US and Canada in wild wildlife populations and animals at captive game farms. Soon, the disease is expected to reach Arizona, Nevada and the three states on the West Coast.
So far, there is no confirmed case of CWD being transmitted to humans via people coming in contact with diseased game animals or by eating them.

However, epidemiologist Dr. Michael Osterholm, whom Mountain Journal has interviewed in the past and who is best known today for his observation about Covid-19, believes animal to human transmission is inevitable. He says it is only a matter of time, given differing emerging strains of prions which continue to mutate and consumption of game meat by large numbers of people, before the species barrier is crossed.

Osterholm during a conversation with Mountain Journal called attention to artificial feeding of wild elk in Wyoming as an example of how not to manage wildlife when CWD is moving through wild cervid populations, and he has also been critical of private captive game farms. The feeding that happens in Wyoming with public elk on public land, promoted and sanctioned by the state, represents the largest complex of artificial feeding of elk in the US and it has attracted national rebuke. 

Recently in Jackson Hole at a webinar on CWD sponsored by the Wyoming Game and Fish Department, state officials said they have no plans to stop artificially feeding more than 20,000 elk that converge every winter on its state feedgrounds, many of which are found on lands managed by the US Forest Service.

Apart from and by itself, the US Fish and Wildlife Service’s National Elk Refuge, which begins at the northern boundary of the town of Jackson, is home to between 7,000 and 8,000 wintering elk. Every major scientific organization in the country associated with professional wildlife management condemns the century-old practice of feeding wildlife because it bunches up animals in large numbers where they become susceptible to catching and transmitting diseases.
Thousands of elk congregate over artificial feed at the National Elk Refuge and 22 feedgrounds operated by the state of Wyoming every winter.  Imagine if this were young human spring break goers in the time of Covid. Would such a convergence be considered wise amid the threat of a contagious disease?  Epidemiologists say the same rules apply to wildlife when there's the looming menace of CWD and brucellosis. Photo courtesy Thomas Mangelsen (mangelsen.com)
Thousands of elk congregate over artificial feed at the National Elk Refuge and 22 feedgrounds operated by the state of Wyoming every winter. Imagine if this were young human spring break goers in the time of Covid. Would such a convergence be considered wise amid the threat of a contagious disease? Epidemiologists say the same rules apply to wildlife when there's the looming menace of CWD and brucellosis. Photo courtesy Thomas Mangelsen (mangelsen.com)
A parallel of why congregating animals is a bad idea can be found in the strategies for why public health officials advise against large human gatherings in the face of the coronavirus pandemic. Notably, Montana and Wyoming forbid the feeding of wildlife by private citizens for the very reason that it elevates the risks of disease transmission, not only for CWD, but brucellosis (which has been passed from elk to cattle in Greater Yellowstone) as well as bovine tuberculosis, pneumonia, hoof and mouth disease and others.

A large number of experts, including the former national chief of animal health for the Fish and Wildlife Service, a veteran wildlife scientist now retired from the Elk Refuge and several refuge managers have said that CWD’s arrival in elk in Jackson Hole is imminent. Three years ago, a mule deer that died literally on the edge of the Elk Refuge and Grand Teton National Park tested positive for CWD.

In addition, more than a half dozen environmental groups have filed lawsuits against the Fish and Wildlife Service and the Forest Service for violating its governing laws that require its management actions to not result in significant harm to resources under its charge.
The area in purple shows where CWD is present in Wyoming deer, elk and moose, some of which migrate hundreds of miles. Note the upper lefthand corner which has Yellowstone and Grand Teton national parks that represent places of convergence for vast herds, some of which might become infected with CWD if it reaches large wapiti concentrations on the National Elk Refuge. Graphic courtesy Wyoming Fish and Game
The area in purple shows where CWD is present in Wyoming deer, elk and moose, some of which migrate hundreds of miles. Note the upper lefthand corner which has Yellowstone and Grand Teton national parks that represent places of convergence for vast herds, some of which might become infected with CWD if it reaches large wapiti concentrations on the National Elk Refuge. Graphic courtesy Wyoming Fish and Game
The main reason for keeping the feedgrounds in operation is they help maintain an artificially inflated population of elk desired by outfitters and guides who sell hunts to paying clients.

Wyoming wildlife officials and politicians have overtly resisted or opposed phasing out artificial feeding at the 23 feedgrounds, based on unproved assertions that it would cause a massive wapiti die-off, result in heightened disease threats for cattle ranchers if elk dispersed more widely, and even asserting they do not believe the CWD threat is as serious as claimed by scientists.  Not lost is the irony that by concentrating wildlife on public land, based on the rationale that they would help reduce the risk of disease like brucellosis to cattle, they are actually creating graver disease threats.

Despite Wyoming for years minimizing CWD as a menace, mule deer herds in southeastern Wyoming have suffered annual losses of more than 20 percent due to CWD. Just to the south, in Colorado, the elk population in Rocky Mountain Park is dropping markedly with CWD being a leading cause of death. Further, a research study done in consultation with Wyoming’s state wildlife veterinarian predicts that after CWD takes hold in elk, animals with the most common genetics could go extinct. To date, no deer family member has demonstrated immunity to CWD and there is no effective vaccine.
A research study done in consultation with Wyoming’s state wildlife veterinarian predicts that after CWD takes hold in elk, animals with the most common genetics could go extinct. To date, no deer family member has demonstrated immunity to CWD and there is no effective vaccine.
Some 20 years ago, three prominent officials involved with wildlife and diseases in Wyoming warned about artificial feeding. And, like warnings offered from federal and independent experts, they were ignored by state biologists, members of the politically appointed Game and Fish Commission and governors.  

“Wildlife have evolved and adapted over millions of years to exist on natural forage. A given amount of habitat can only support a given number of animals. Often, we destroy habitat, which then leads to wildlife dying of starvation. Feeding allows us to think we are compensating for habitat destruction when, in fact, it makes a bad situation worse,”  wrote  Walter Cook and Jim Logan, both state veterinarians, and Scott Smith, a brucellosis biologist.

“We need to face the fact that the only way to offset habitat destruction is via habitat improvement. The evidence is undeniable. ‘Wildlife are adapted to survive winter without supplemental feeding. Feeding causes many more problems to wildlife than it solves. Additionally, it can be harmful to humans and domestic animals.”

Sixteen years later, Wyoming State Wildlife Veterinarian Mary Wood stood before the Wyoming Game and Fish Commission and said, “If we want to really look at proactive management, the single most proactive thing we can do for feedgrounds in the face of CWD is to find ways to reduce reliance on feed before CWD ever hits.” She then noted, “We know that will occur. I would be doing my profession and the oath that I took as a vet a disservice if I didn’t say artificially concentrating animals over a feed source will facilitate disease transmission.”
"We know that will occur. I would be doing my profession and the oath that I took as a vet a disservice if I didn’t say artificially concentrating animals over a feed source will facilitate disease transmission." —Dr. Mary Wood, appearing before the Wyoming Game and Fish Commission when she served as chief wildlife vet for the state.
Dr. Wood has since left Wyoming and today is state veterinarian for Colorado Parks and Wildlife. Earlier in 2020, Colorado reported that CWD is now present in 33 of 54 deer herds, 14 of 43 elk herds, and two of its nine moose herds. The prevalence is rising in many of those populations. In 18 deer herds, CWD prevalence exceeds five percent with a higher rate in mule deer than whitetails.

History has shown that CWD rates of infection often deepen over time and as they rise the cumulative year after year toll can cause significant population declines. Six big game herds in Colorado have prevalence rates in excess of 20 percent meaning at least one out of every five adult males have the disease, are doomed to die and represent vectors for passing it onto other herd members. Telling is that population declines commence when infection reaches 13 percent.

Given that in the Greater Yellowstone and nearby surrounding states, there are many hundreds of thousands of deer and elk, CWD striking animals in feedgrounds which then spreads more widely could bring epic challenges.
A research elk in Wyoming afflicted with CWD and showing overt symptoms of the disease in its final days of life. Photo courtesy Wyoming Fish and Game
A research elk in Wyoming afflicted with CWD and showing overt symptoms of the disease in its final days of life. Photo courtesy Wyoming Fish and Game
In response to growing public pressure, Wyoming has tried to go on a PR offensive, announcing last year that it was launching a new collaborative process of listening sessions held across the state and sanguinely titled “Toward A Sustainable Future.”

Critics say Wyoming has more than enough information than it will ever need to justify phasing out feeding before a crisis arrives on the feedgrounds. And they assert that just as with coal mining and politicians claiming it had a bright future as market forces—namely the proliferation of cheap natural gas—caused its collapse, leaders seem determined to buck the truth on CWD, too.

At Wyoming’s CWD webinar last week, Game and Fish wildlife health laboratory supervisor Hank Edwards and Scott Edberg, the agency’s deputy chief of wildlife, still, despite Wood’s earlier admissions, would not recommend phasing out the feedgrounds even after hearing from prominent scientists over the years, asserting that keeping them open could result in disaster. 

In 2019, US Sen. John Barrasso of Wyoming sponsored a bill with his Democratic colleague, US Sen. Michael Bennett of Colorado, that would instruct the US departments of Agriculture and Interior in consultation with the well-respected National Academies of Sciences to develop "best management practices" and  identify "the pathways and mechanisms for CWD transmission." It was endorsed by a number of sportsmans' groups and an organization called the Association for Fish and Wildlife Agencies. 

"Wyoming’s deer, elk and moose populations have been negatively impacted by chronic wasting disease for decades,” Barrasso stated in a press release. "We need to know more about how this disease spreads and which areas are most at risk. Our bill gives wildlife managers the tools they need to research and identify exactly where chronic wasting disease is most prominent and how we can better prevent it."

One of the obvious culprits in his own state, the proverbial "elephant in the room,"  was right before Barrasso's eyes and he knew it: the feedgrounds, CWD watchdogs say.  Within the professional wildlife establishment, there is no disagreement about this and no need for the government to spend money or draft legislation. One need only read the technical report on best practices for confronting CWD, spelled out in a benchmark report issued by the Association of Fish and Wildlife Agencies (AFWA)—of which Wyoming Game and Fish and the federal Fish and Wildlife Service are members. The AFWA itself signed on as a supporter of Barrasso's bill. 

The title of the AFWA's document published half a year before Barrasso issued his press released and co-sponsored a bill?  "Technical Report on Best Management Practices for Prevention, Surveillance, and Management of Chronic Wasting Disease."  Apparently neither the senator nor his staff read it, for it identifies precisely what Barrasso claimed to be after.

"To reduce the risk of CWD transmission and establishment of CWD through unnatural concentrations of cervids, states and provinces should eliminate the baiting and feeding of all wild cervids using regulatory mechanisms such as jurisdictional bans," the contributors and reviewers of the AFWA report write. 

They go on: "From the perspective of control and management of infectious diseases, anything that aggregates animals will, in most circumstances, also increase the opportunity for disease transmission. While natural aggregations of animals exist due to a variety of behavioral, seasonal, and resource factors, human-associated aggregations related to baiting and feeding can greatly increase the risk of disease transmission due to increased animal numbers and concentrations over extended time periods. This can lead to exposure to larger doses of infectious agents, multiple exposures, or exposures sustained over prolonged periods of time all resulting in greater probability of infection."

If that weren't enough, they knock down, without naming names, Wyoming's main arguments for keeping the feedgrounds open. "There is currently no evidence that baiting and feeding of free-ranging cervids can be conducted to mitigate increases in the opportunity for disease transmission. There is also no evidence the practice is likely to increase harvest sufficiently to overcome the negative effects of those increases by disease transmission."

What's noteworthy? Dr. Mary Wood, while still state vet for Wyoming, and Hank Edwards, Wyoming's current wildlife health laboratory supervisor, were part of the esteemed group that issued the paper. Edwards' own conclusions and those of his colleagues at Game and Fish today run counter to not only his professional peers beyond Wyoming who penned the AFWA report but the mountain of evidence they drew upon.
A report on best practices to combat CWD, released by the Association of Fish and Wildlife Agencies (and of which Wyoming is a member) states in no uncertain terms that artificially feeding wildlife runs counter to expert scientific opinion and mounds of evidence. Still, Wyoming chooses to defy what all other wildlife professionals say is the truth.
Retired Elk Refuge biologist Bruce Smith, author of the critically-acclaim book Where Elk Roam has said CWD reaching high infection rates in wintering elk, combined with the shedding of prions into soils, could create a biological Superfund site. Pretending it couldn’t happen, refusing to take bold action to prevent it from happening, he said, is antithetical to the ethics and standards of professional wildlife management in the 21st century.

Further, Dr. Tom Roffe, who oversaw animal health for the whole of the Fish and Wildlife Service and has since retired to a ranch in Montana, has told Mountain Journal in the past that Wyoming has for decades stalled action it knows it needs to take and when given the option of adhering to disease prevention practices embraced by the rest of the world, has demonstrated its proclivity “for taking every course of action possible except for the right, cautious one.”

Smith and Roffe, both lifelong avid hunters, say they will no longer eat game animal meat from areas where they know the incidence of CWD is established and rising. They also will be very wary of feeding game meat, without knowing its source and origin, to their families for dinner. Both said it is not their intent to judge others. Calmly, Roffe said in an earlier interview, "Some may want to take the chance and believe it [animal to human transmission] will never happen. And good for them. But I'm one who thinks if I don't have to take the risk, then why do it?"
In the field, hunters are advised to wear gloves when field dressing game in a CWD endemic area even if animals show no overt symptoms of disease. Experts say that infected deer family members can remain asymptomatic and spread CWD via saliva, urine, feces and via body decomposition.

The first CWD-infected deer confirmed in Montana appeared healthy when they were taken by hunters. Notably, there are no reliable tests that can be given to live animals to tell if they carry the disease; only after they are dead do tests work.

Montana Fish Wildlife and Parks spokesman Greg Lemon said that because CWD is known to be a disease slow to move into a wildlife population and not as infectious as other maladies, it is important to keep a calm head in pondering what its presence means. He expects that as more test results come back, the number of positive cases is certain to go up.

“We have numbers right now that are a bit of a moving target,” Lemon said. “Batches of results are starting to come in and there are quite a few samples still getting processed. We’re expecting more positives to come through around the state. What’s clear is we have a hot spot in the lower Ruby Valley involving whitetail deer.” He added there's also a higher-incidence of disease in deer in an area northeast of Dillon.  

Lemon said the rising number of confirmed cases appears to correlate to a rising number of test samples being checked. While many have speculated that CWD’s arrival in southwest Montana may be owed to the disease spreading from mixing with infected wildlife in Wyoming, Lemon said surveillance and mapping actually show the disease is present statewide.

CWD has been found in the northwest corner of the state nearby Libby, in northern parts of Montana near the border with the Canadian provinces of Alberta and Saskatchewan and in the east along Montana’s border with North and South Dakota.  “If people are hunting in Montana they should assume it’s possible that CWD is present where they’re killing an animal to have meat in the freezer,” he said. “The best way to have peace of mind is to have the animals tested before you eat it”

Every year the conservation groups Wyoming Wildlife Advocates and Sierra Club have produced maps showing the progression of CWD  in the state. From 2001 to 2019, the disease expanded in Wyoming elk hunt areas at an average rate of 762,000 acres per year. The endemic area (where a disease is commonly found and present within a particular place) for deer  has expanded around two million  acres per year over the same time, more than double the annual rate of expansion for elk.  

Wyoming Game and Fish announced a few months ago that CWD turned up in an infected elk near Cody off the east side of Yellowstone Park but many believe it may already be present in America’s first national park where every summer herds of elk and mule deer converge from across the tri-state region.

How CWD might impact wildlife in Yellowstone is not known but scientists say it will not be good. At the same time, some biologists believe that healthy populations of Greater Yellowstone’s “predator guild”—wolves, cougar, bears and coyotes—may be helping to slow CWD as they kill prey that are weak and vulnerable from infection, thereby preventing them from infecting others. Just as with humans, there has not, as of yet, been a documented case of CWD afflicting predators.

The federal Centers for Disease Control recommends that people should not eat game animals known to be infected with CWD, as even cooking at high temperature does not kill prions.

In Montana and Wyoming presently there are no carcass transport restrictions, though in eastern states it is illegal to move carcasses out of counties where CWD is known to exist. A carcass may be moved anywhere in Montana regardless of where it was harvested as long as the carcass parts are disposed of in a landfill after butchering / processing. Carcass parts, such as brain, eyes, spleen, lymph glands, and spinal cord material, should be bagged and disposed of in a landfill or may be left at the kill site.

This latter recommendation is itself somewhat controversial because prions are known to be able to exist in the environment for years and have, under laboratory conditions, been shown to be absorbed in the tissues of plants and persist in soils.

One major worry at the feedrounds in Wyoming is that CWD could create toxic zones of environmental contamination leading to chronic infection of animals in a certain area. The concern is not without reason. At a state research facility in Wyoming, a study group of elk became sickened with CWD—and all died—after being placed inside pens where CWD-infected animals early had been and were gone.

Dr. Michael Osterholm Photo courtesy CIDRAP
Dr. Michael Osterholm Photo courtesy CIDRAP
Dr. Osterholm, who was remarkably prescient in his predictions for how the Covid pandemic would play out, was recently asked to serve on President-elect Joe Biden’s national public health task force. Osterholm is a specialist in zoonotic diseases (diseases that move between humans and animals) and he has been part of fact-finding teams investigating Mad Cow and Ebola.

In 2018, as director of the Center for Infectious Disease Research and Policy (CIDRAP) at the University of Minnesota, he made headlines by being publicly vocal about the consequences of CWD spreading through wild deer in big hunting states like Minnesota, Wisconsin and Michigan. He says that untold thousands of people in the US have consumed CWD-contaminated meat. The Alliance for Public Wildlife estimates that 7,000 to 15,000 CWD-infected animals are consumed annually, a number that may increase by 20 percent each year 

While Osterholm says that focusing on sources of potential accelerated spread should be a primary focus, in addition to more federal investment in research and development of a national strategy, he cautioned that should a human case of CWD be confirmed, a major challenge will be containing hysteria. 

Hunting, he says, is an effective tool in culling animal herds and it helps maintain public support for wildlife management agencies. Often herd reduction efforts focus on bucks and bulls.

Osterholm cautioned that fear about disease, often fueled by misinformation, can undermine public confidence in prudent management which is crucial in confronting a frightening zoonotic disease like CWD.

Just because animal to human transmission has not yet been confirmed, this does not mean it will not, he said, noting the same assumption was made about cattle and people in Britain. There remains a lot of unknowns about CWD, the same as there was about Mad Cow, but the hard-won lessons of epidemiology do not go away simply because people, for political decisions, claim they do not exist or apply to them.

Osterholm told Mountain Journal that states need to pay more serious attention to the possibility of prions contaminating the meat of healthy animals at processing plants and resulting in chronic contamination on surfaces. And vigilance is required in monitoring deer and elk in captive facilities, where outbreaks have occurred in the US and Canada.

In a peer reviewed journal article published in mBio in 2019, Osterholm and four other authors wrote, "Available data indicate that the incidence of CWD in cervids is increasing and that the potential exists for transmission to humans and subsequent human disease. Given the long incubation period of prion-associated conditions, improving public health measures now to prevent human exposure to CWD prions and to further understand the potential risk to humans may reduce the likelihood of a BSE-like event in the years to come."

Surprising to some readers here is that in 2001 CWD was declared a national emergency yet as its reach has proliferated and states are having to do more with coordination of testing, management responses and hunter education, government investment in research and public health has not kept pace.

Titling their recommendation "a call to action," they write: "Despite the best efforts of wildlife agencies and other organizations to combat CWD, a unified approach has not been developed. A comprehensive strategy, with national leadership and support, is needed to address this important public health risk."  They also call for mandatory national testing of big game animals so that a baseline can be established to make more informed decisions. And, yes, there is an economic interest at stake. "Without comprehensive, effective changes in wildlife management and the captive cervid industry, the nearly $40 billion annual contribution of wild cervid hunting in the United States is under threat," they say.
"Despite the best efforts of wildlife agencies and other organizations to combat CWD, a unified approach has not been developed. A comprehensive strategy, with national leadership and support, is needed to address this important public health risk." 
While there remain a lot of what ifs—including whether crossing of the species barrier is biochemically possible—Osterholm says the possibilities increase when there is a convergence of risk factors. Prions continue to demonstrate an ability to mutate into new strains, more animals are getting infected, more land and more human surfaces could become prion contaminated, and more meat consumed. "Evidence...suggests that emerging CWD strains could have broader host ranges and higher zoonotic potential. A lack of assurance of an absolute species barrier necessitates a preventive public health approach."

This is what Wisconsin, which has been criticized for not being more vigilant earlier, now advises: “CWD prions persist throughout the body of an infected animal, even before the onset of clinical symptoms. While handling and moving deer tissue, prions may bind to surfaces and remain infectious for long periods of time. It is important to minimize the spread of infectious material by properly cleaning work surfaces, equipment, and clothing.”

The recommendation goes on by saying that the following procedures should be followed to properly contain and clean equipment exposed to CWD-infected tissues:  “Line trash receptacles with non-porous, single-use liners that can be sealed or enclosed. Minimize infectious material in wastewater drains by removing and disposing of solids and other carcass debris from work surfaces, equipment, and PPE (personal protective equipment, the same equipment used during the Covid-19 pandemic). Pressure wash any vehicles or equipment to be moved to and from areas of known CWD contamination. Properly contain carcass waste in double-lined trash bags and dispose of in acceptable landfill. Properly contain disposable clothing and equipment in double-lined trash bags and dispose of in landfill. Thoroughly wash non-disposable PPE prior to removal from contaminated site.”

As mentioned above, epidemiologists say surfaces contaminated with prions can be difficult to disinfect. “Not only is it important to clean all materials and surfaces that have been exposed to potentially contaminated tissues of all organic solids, but also to use additional methods to attempt to deactivate the disease agent prion. CWD prions are unusually resistant to traditional chemical and physical disinfection and sterilization methods. The most generally accepted method for complete decontamination of prion infected material is incineration at 1800 degrees Fahrenheit.”

The Wisconsin advisory, consistent with those in other states, adds: “But because incineration is impractical for most people, it is recommended that equipment and surfaces undergo disinfection by soaking in a bleach water solution…Soak all appropriate processing equipment and surfaces in a 50:50 bleach water solution for at least 1 hour. Rinse all equipment and surfaces with clean, hot water after soaking in bleach water solution.”

As with the controversies surrounding collective action for confronting Covid, there are segments of the general public that have demonstrated an obstinance in taking seriously precautions for CWD. Hunters in many states simply choose to eat meat and not get their game tested. Not long ago, it was reported that the Wisconsin Department of Health Services maintains a list of individuals who have consumed CWD-positive animals and nearly 1,000 people have agreed to participate in the state’s long-term disease surveillance program.
Accompanying the box of steaks, roasts, burger and salami home is also suspicion of how did your deer or elk get processed among all of the others? Merely mentioning the acronym CWD can cause indigestion.
One thing is certain, in many states gone are the carefree days when nothing but sublime sentiments were associated with the act of putting natural food on the table and choosing from an array of how venison or other game meat could appeal to the palate. Accompanying the box of steaks, roasts, burger and salami home is also suspicion of how did your deer or elk get processed among all of the others? Merely mentioning the acronym CWD can cause indigestion.

In Michigan, health officials advise that if you are processing deer from a CWD core area or management zone, the waste, inedible materials, spinal cord, brain tissue and other material should be handled in a specific manner. “Waste created from the processing of the carcass should be bagged and sent directly to a landfill. Do not render, burn, compost or place in the environment parts from deer that potentially have Chronic Wasting Disease as this could contaminate the environment or soil and spread the disease.”

Specifically regarding the handling of game meat, Michigan officials say: “Segregate any suspect venison from larger comingled batches of sausages, snack sticks, etc., and do not process until the test results come back negative.”

In their scientific paper in mBio, Osterholm and colleagues assert that faster, better diagnostic testing for CWD  urgently needed and labs need to have improved capacity because hunters in many states have to wait weeks for results after they kill their game animal. "This delay is significant, since hunters might choose to process or consume the meat from cervids in the interim," they write. "This could lead to unrecognized and unnecessary exposure to CWD prions and contamination of meat-processing equipment, as prions have been shown to bind to metal without losing infectivity."

Somewhat worrisome, the authors pointed again to Wisconsin and highlighted why caution should be the watchword. "Despite the Wisconsin DNR offering CWD testing to hunters in surveillance areas at no cost, only 5 percent of Wisconsin’s 336,464 deer harvested in 2018 were tested.  Furthermore, only 4,925 of the 23,441 deer harvested in four Wisconsin counties (Dane, Iowa, Richland, and Sauk) where CWD is most established were tested in 2018, with 894 (18 percent ) testing positive. More than 18,500 deer harvested in these four Wisconsin counties were not tested for CWD, suggesting that the meat from at least 3,000 CWD-positive animals was consumed, given the previously determined prevalence. Until gaps in CWD surveillance are addressed, the extent of CWD in cervid populations will remain unknown and people will unknowingly consume prion-infected meat."

Lemon of Montana Fish Wildlife and Parks told Mountain Journal earlier this year that discussions have occurred on a number of levels, stretching from hunters going afield to legislators and the governor, about how prion containment regulations might be applied to commercial game meat processors the same as the US Department of Agriculture regulates beef slaughterhouses.

Optimists would say there is good news relating to the December announcement that five new hunting districts in Montana have been added as areas where CWD is present. The upshot is that only single deer in the Gallatin, Paradise, and upper Madison valleys tested positive. But those are big dells and they are home to a lot of wildlife. Isolated solo cases of CWD are extremely rare and where there's one infected animal there's likely several more. With Paradise Valley, it reaches almost to the front doorstep of Yellowstone and every winter herds of hundreds of mule deer and elk can be seen along the flanks of the mountains north of Yankee Jim Canyon.

Until a lot more is known and a lot more test results come in, hunters and the public in Greater Yellowstone, when it comes to navigating the potentially perilous terrain of CWD, will be doing so in the dark.

Todd Wilkinson
About Todd Wilkinson

Todd Wilkinson, founder of Mountain Journal,  is author of the  book Ripple Effects: How to Save Yellowstone and American's Most Iconic Wildlife Ecosystem.  Wilkinson has been writing about Greater Yellowstone for 35 years and is a correspondent to publications ranging from National Geographic to The Guardian. He is author of several books on topics as diverse as scientific whistleblowers and Ted Turner, and a book about the harrowing story of Jackson Hole grizzly mother 399, the most famous bear in the world which features photographs by Thomas Mangelsen. For more information on Wilkinson, click here. (Photo by David J Swift).
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