May 5, 2004 Fort Collins Weekly  by Lori Russell

During hunting season, Dalley frequents area 191—a section of land in Northern Colorado notorious for its population of deer and elk that are infected with chronic wasting disease. CWD has been successfully tracked in area 191—and throughout the region—thanks in large part to hunters who were required to submit the heads of killed game to the Colorado Division of Wildlife for CWD testing. It's estimated that 70 percent of all game killed in Colorado during the last hunting season was tested at no charge to hunters. Testing deer and elk helped track the spread of the disease and provided a measure of safety to hunters whose freezers were packed with meat from their kills.

All that is changing for the coming hunting season.

The Colorado Wildlife Commission has decided to eliminate its mandatory CWD testing requirements in favor of a paid voluntary system. Hunters like Dalley are worried that the disease will vanish from the radars of state and local health agencies. Even the DOW admits, in an August 2003 memo, that eliminating the mandatory testing requirements will likely result in a 50 percent reduction in identifying animals that test positive for the deadly disease. That would result in a corresponding reduction in the agency's ability to manage and control its spread.

"I'd like to continue to see mandatory testing," Dalley says. "I understand the budget constraints, but that's the only way we know whether the disease is being reduced or if it's being spread."

Dalley isn't the only concerned hunter in the region. The decision to return to voluntary submission is explained by DOW officials as an effort to reduce bureaucracy for hunters while still providing enough data to allow scientists to track the disease. But the change has upset many who are concerned about the potentially dangerous nature of the epidemic, with some feeling that the DOW is downplaying a possibly serious—and largely unknown—human health threat.

"They're basically telling hunters not to worry about chronic wasting disease," CWD activist Jim Woodward says of the decision. "That advice goes against the recommendations of every major public health organization in the world. Unfortunately there's not enough recognition of this issue, particularly in the hunting community."

CWD is a transmissible neurological disease that produces small lesions in the brains of deer and elk. Characterized by loss of body condition, behavioral abnormalities and imminent death, this transmissible spongiform encephalopathy (TSE) is similar to mad cow disease, scrapie in sheep and Creutzfeldt-Jakob disease in humans.

TSEs are believed to be spread through infectious prions, abnormally folded proteins that concentrate in the central nervous system—the brain, spinal column, spinal cord, lymph nodes, eyes, tonsils, spleen and pancreas. It is believed that these prions convert adjacent proteins, affecting brain tissue and ultimately causing tiny, sponge-like holes. TSEs are contagious and are spread through contact with infected tissue. The jury is still out on whether or not animal TSEs can be spread to humans.

"We're concerned about TSEs because they're so devastating and untreatable," explains Byron Caughey, Ph.D., senior investigator in the Laboratory of Persistent Viral Diseases at Rocky Mountain Laboratories in Hamilton, Mont. "It seems to me that it makes sense to remain vigilant for signs of potential problems for humans."

Caughey explains that CWD and Creutzfeldt-Jakob are similar, but is quick to point out that this doesn't mean that one causes the other. He labeled it "theoretically possible," however, cautiously acknowledging that there could be a connection between them.

Colorado Department of Public Health and Environment epidemiologist John Pape has also been engaged in recent TSE research. Actively involved in the study of TSEs since 1997, Pape claims that in multiple years of study, the department has yet to develop evidence that humans can contract CWD by eating infected meat although he admits there isn't enough data to rule out the possibility. While there have been no verified human cases of CWD, and though earlier research has suggested that humans, cattle and other domestic livestock are largely resistant to natural transmission of CWD, recent studies have surfaced calling those conclusions into question.

During a statement before the U.S. Senate Committee on Appropriations by Dr. Julie Gerberding, the director of the Centers for Disease Control and Prevention, it was noted that as of February 2004, mad cow disease has caused 156 human cases worldwide, and when considering the similarities between mad cow and CWD, concluded that it would seem prudent to take precautions to limit the exposure of humans to CWD.

Even more disconcerting, according to MedlinePlus, a service of the U.S. National Library of Medicine and the National Institutes of Health, anywhere from 5 percent to 30 percent of the country's 4.5 million Alzheimer's cases are potentially misdiagnosed cases of Creutzfeldt-Jakob, though these cases could be naturally occurring. The conclusion is based on four separate autopsy studies of dementia patients.

"The bottom line is that there are a lot of unknowns," Woodward elaborated. "But there's enough evidence out there to suggest that you should definitely minimize human exposure to CWD."

According to the DOW, the presence of CWD has reduced both the growth and size of wild game populations—especially in the endemic areas of northeastern Colorado, southeastern Wyoming and southwestern Nebraska. The disease has also recently been identified in several new areas across the continent as well as in commercial game farms. An email conversation between CSU researchers and DOW officials in September discussed apparently positive CWD results for elk from areas where elk were not known to be infected with the disease.

The elk tissue was sent by hunters required under the old rules to submit heads for testing. The email concludes that "if these results are not from areas that are currently positive, it might cause a small ruckus."

Spreading responsibility

In the 2003-2004 hunting season, 16,431 deer, elk and moose were submitted for CWD testing by Colorado hunters. Of this sample, the disease was detected in 248 instances, including in 51 animals from outside of the established endemic area.

According to DOW spokesman Todd Malmsbury, mandatory submission for CWD testing was primarily invoked for the purpose of acquiring adequate sample sizes to monitor the spread of the disease. One department document went on to explain that if returned to voluntary submission, the DOW would likely still obtain an adequate number of samples from these northeastern endemic areas—somewhere around the statewide average of 25 percent—but down from the estimated 70 percent they received when submission was mandatory.

According to Malmsbury, the DOW's primary responsibility with CWD is to collect surveillance data to monitor the rate of infection and potential spread of the disease—responsibility for protecting hunters' health lies with other agencies. By forcing hunters to submit their animals, Malmsbury feels the DOW created needless bureaucracy and another unnecessary level of policy for hunters to navigate.

"We don't need to have another regulation requiring testing," he says. "But we certainly encourage hunters to come in and have their animals tested. We're going to continue to make the management of chronic wasting disease a top priority."

Some DOW watchdogs, including Woodward and Bill Brown, co-founders of the group Friends of the Wellington State Wildlife Area, interpreted the change as evidence that the DOW has from the beginning been disinterested in the possible public health ramifications that may result from human consumption of game infected with CWD.

According to Woodward and Brown, the decision to eliminate mandatory testing was made with virtually no discussion outside of the Wildlife Commission and the DOW, in turn becoming a sore subject among concerned hunters and uneasy public health officials.

Larimer County Board of Health President Frank Vertucci voiced the board's recent concern about a DOW proposal to locate an incinerator for the disposal of CWD tested animals near Wellington. In a letter, he requested that, as the nature of prion diseases and their methods of spreading are still greatly unknown, the commission should look at the issue more broadly—possibly even with a public forum—before making their final determination. Former DOW director Russell George, now head of the Department of Natural Resources, responded with a letter stating that the division was "not in a position to support the formation of a committee to identify an optimal solution at the present time, as we feel there is adequate information already published on the topic."

However, in March, the DOW announced that it had shelved the Wellington incinerator plan due to the significant decrease in testing demand since the overturn of the mandate—not due to public health concerns. The Board of Health is pleased nonetheless, according to Vertucci.

"All the literature points to the idea that there's no evidence that it is transmissible to humans," Vertucci says of CWD. "But there's also no evidence that it's not."

Vertucci worries about the consequences that removing mandatory testing may have on peoples' perceptions, believing that it downplays the issue to the hunting community. The Board of Health is adamant that hunters continue to take the risk seriously, stressing the need to take proper precautions when handling and processing game. At the beginning of next season the board will issue a press release encouraging hunters to continue testing for CWD, despite the overturning of the mandate.

"Measures should still be taken to test the animals and avoid contact with the disease," Vertucci says. "We want to make sure that these changes in policy are reflected by an increased vigilance to encourage hunters to take every precaution."

Though both Dalley and Virgil Hawkins, who has been hunting in the affected area for some 50 years, are doubtful of the possibility of a connection between CWD and human neurological disorders, both hunters continue to have their game tested.

"Not only does it benefit the hunter," Hawkins says, "but it would also benefit Fish and Game to know a little bit more about what's going on in the area."

"Anybody with any common sense at all should be concerned about it and take some precautions," Dalley says, "but as far as scaring me off to where I'm not going to hunt in that area anymore—no."

"It's from the deer meat"

But the testing protocols themselves do not come without their share of criticism. Hunters say their potential health and well being often take a back seat to the tracking aspect of the research.

"It didn't have anything to do with providing a service to hunters," Woodward says of the now defunct mandate. "The only reason they did it was for scientific data."

In the past, DOW collected animal heads for testing at the Foothills Laboratory where technicians removed the lymph nodes and sent them to CSU's Veterinary Diagnostic Lab. There they were given an initial rapid screening test known as an ELISA test, which posted results within three days. If the results of this initial test were positive for CWD, the lab's policy was to perform a confirmation test using an IHC test, which has an accuracy rate of greater than 90 percent, according to Malmsbury. If the IHC test proved the positive result, only then did the DOW inform the hunter.

Woodward and Brown, however, feel that this process took an exorbitant amount of time, noting that most hunters process their game within three to seven days.

"The hunter should be given that initial information after a few days so that they can make the decision whether or not to have their meat processed," Woodward says.

Malmsbury, in turn, explained that despite the initial findings in positive cases, the DOW waited to contact hunters until they were certain of the results, avoiding false reports that could cause additional confusion—and possible damage to the state's hunting industry, which typically sells approximately 20,000 hunting licenses per year. Hunting is a nearly $600 million per year industry in Colorado, according to DOW's own estimates.

The DOW's rigorous testing process is unfortunately of no comfort to Nicki Berns of Thornton, whose father Otto Berns, a lifelong hunter and avid venison eater, died of Creutzfeldt-Jakob in 2002. Though an autopsy was never performed to verify the family's suspicion that the disease resulted from chronic wasting disease, Berns is still convinced that game meat was responsible for her father's death.

Before his death, doctors conducted a brain biopsy, which was sent to the National Prion Disease Pathology Surveillance Center in Cleveland. Testing revealed findings consistent with Creutzfeldt-Jakob, but according to Berns, the tests actually showed that her father was suffering from scrapies. When asked how researchers explained this, she says: "They didn't explain anything. They avoided everything."

Berns is convinced that state officials know more than they are letting on. Why else, she asks, would health department investigators have asked questions about trips abroad and about her father's hunting habits? Why also, she asks, did epidemiologist John Pape insist that her and her mother no longer donate blood? If doctors were only worried about the naturally occurring genetic strain of CJD, why should her mother, who was not blood related to her husband, be restricted from donating?

"They can say whatever they want, but it's from the deer meat," Berns says. She's so convinced that she has offered many times to prepare a meal for state officials using venison still in the family freezer—offers that have always been declined.

"I just want to get the right information out to people so they can make an informed choice," she says.

Pape declined to discuss the Berns case, citing confidentiality issues, but says that in cases involving neurological diseases, the Department of Health investigates in order to determine whether the case is naturally occurring or is a variant strain. The health department has made great strides in making such determinations in recent years, he says, but admits that there is still work to be done.

"Clearly there are a lot of gaps in our understanding right now," Pape says. "But we're starting to fill in those holes."

However, Berns believes that because the DOW and the state as a whole rely on selling hunting licenses for a significant portion of their revenue, they have continued to focus all their efforts on maintaining the industry rather than looking out for the best interest of the hunters.

Brown cites his own alarming CWD experience earlier this year, during which the DOW didn't inform him of the positive results of his own mule deer for three weeks. Brown claims that during those three weeks, he called the DOW three times, leaving messages requesting his results in each instance.

"That was grossly, grossly irresponsible of them not to contact me right away," he says.

For this reason, Woodward and Brown feel that the DOW should adopt a new policy in which the rapid screening test results are relayed to the hunter within three days—giving the hunter the option to either move forward with the butchering process while awaiting the results of the confirmation test or to dispose of the animal.

Brown did eventually received a call from the DOW confirming that the animal, which had appeared healthy, had tested positive for CWD. According to Brown, the caller from the DOW went on to encourage him to soak any instruments used in field dressing the animal in a 50/50 bleach solution and to destroy any knives and sheaths used in the process. Brown also said he was not directed in how to dispose of the carcass, but was told he could bring it to the DOW if he wanted.

Hunter education

According to Woodward and Brown, most hunters are unaware of the persistent and potentially dangerous nature of CWD. For this reason, they feel that the DOW should begin an education program for hunters and should implement numerous changes in their protocol regarding the disease.

As an alternative to removing the animal's head, and therefore severing the spinal cord—a main center of the disease—Woodward and Brown suggest that hunters could receive training to remove the animal's lymph nodes, with the DOW issuing or selling removal kits to hunters and veterinarians with detailed instructions, sampling packages and disposable equipment. They further suggest that the DOW could establish sampling stations where technicians could remove tissue for testing or could possibly require game processors to remove tissue for testing before butchering the animal. Brown also notes the option of field disposal by means of a mobile tissue digester like those in use in heavily affected CWD regions in Wisconsin—especially following the recent release of a report by researchers from the DOW, CSU and the University of Wyoming, declaring that indirect transmission can occur through environments contaminated by decomposed carcasses or by excreta.

Woodward and Brown ultimately agree with Malmsbury that the DOW should not be responsible for addressing human health concerns. They feel that this responsibility would be better served by state and county health departments.

"But they've made no recommendations to the public at large on the hunting issue," Woodward says of the state health department. "They have absolutely no guidelines whatsoever regarding human exposure to CWD, or any other TSEs, with the lone exception of a few field dressing guidelines for hunters. As far as I'm concerned, the state health department has dropped the ball."

Hunting for CWD

The Colorado Division of Wildlife strongly cautions hunters not to consume meat from animals suspected of having chronic wasting disease and to take precautions when field dressing animals from the endemic area. Infected animals often seem disoriented, drool uncontrollably and behave erratically.

Hunters wishing to have their animals tested can bring them to designated collection sites—to be announced as hunting season draws nearer—where tissue samples will be removed. Hunters will be given the option of keeping the animal's head if they wish to mount it or of having technicians dispose of it. Priced at approximately $15, DOW spokesman Todd Malmsbury calls the voluntary testing relatively inexpensive, accessible and quick, with results to be returned within 14 days.

Despite the end of mandatory CWD testing for hunters, the DOW continues to develop more sensitive CWD testing procedures and early detection methods. Research into the relationship between deer density and disease prevalence, as well as its geographic distribution will be ongoing as a result of the voluntary testing. Other ongoing studies include determining if CWD can be passed to other animals—especially predators— and research into possible links between the disease and human neurological disorders.