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Scientists Worry That the Incurable “Zombie Deer” Disease Could Make the Leap to Humans

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Deer (and related animals, like elk) in 24 states that have tested positive for chronic wasting disease – sometimes referred to as the “zombie deer” disease, and scientists are worried that humans might not be immune to catching it, should we eat tainted meat.

The disease causes infected animals to stumble through the forest, drooling and becoming more aggressive toward humans. They’re listless, consistently lose weight, and will eventually die from the incurable infection.

It’s the result of a prion – a mis-folded brain protein that’s mysteriously able to infect other nearby proteins, talking them into re-folding wrong, too. A prion is not alive, so it cannot be killed, which means there are no treatments or cures for chronic wasting disease or any other prion diseases like it.

We’ve been aware of these types of infections, and how hard they are to fight, for years. Mad Cow Disease is the result of prions, as is Jakob Creutzfeldt Disease. In humans, prion disorders cause people to decline over the span of several months; they lose the ability to speak, move, and eventually control the muscle movements necessary for life.

CWD (Chronic Wasting Disease) currently seems limited to deer, moose, and elk, but researchers at the University of Minnesota are urging local lawmakers to consider funding further research into the matter.

Michael Osterholm, the university’s Center for Infectious Disease Research and Prevention director, is at the forefront of the effort.

“It is my best professional judgement based on my public health experience and the risk of BSE transmission to humans in the 1980s and1990s and my extensive review and evaluation of laboratory research studies …that is it probably that human cases of CWS associated with the consumption of contaminated meat will be documented in the years ahead. It is possible that the number of human cases will be substantial and will not be isolated events.”

Basically, even though as of yet there is no reason to panic, scientists are sounding the alarm.

Osterholm has reason to be concerned – he was involved with the British review panels that dealt with the mad cow disease scare, when it was found that it was rare, but possible, for humans to contract the disease by eating contaminated tissue.

That said, all evidence points to the consumption of brain tissue specifically as being the means for transmission, not other, more commonly-eaten portions of meat.

The existence of CWD in deer and the potential for contraction in humans is not news to the CDC – since the 1990s, they’ve kept an eye on hunters who come down with versions of the prion disease killing the deer. Many are diagnosed at surprisingly young ages, and some were known to eat deer meat regularly.

All of the patients died not long after their symptoms emerged, but in all cases, no known herds infected with CWD were in the area.

Basically, there was no way to confirm that they contracted anything at all from eating contaminated deer meat – some of the men weren’t even conclusively diagnosed with prion infections – so it could have been a simple coincidence.

Rates of prion disease in human aren’t any higher in areas rife with infected deer than anywhere else in the United States, but scientists are also quick to point out how little we know about the afflictions overall.

This CDC report states that “because CWD has occurred in a limited geographic area for decades, an adequate number of how people may not have been exposed to the CWD agent to result in a clinically recognizable human disease. The level and frequency of human exposure to the CWD agent may increase with the spread of CWD in the United States.”

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The progression of chronic wasting disease in North America (CWD) since 2000. CWD is a highly contagious disease in cervids (deer, reindeer, elk) that degrades the animal’s neurological system, leaving holes in the brain. It is 100% fatal. ⠀ Although there are no known cases of CWD in people, there is concern that the prions that cause the disease could adapt to new hosts and someday infect humans, just as the prion culprit of mad cow disease did in the United Kingdom in the 1990s. ⠀ To offer her expert testimony and recommendations, wildlife disease ecologist Dr. Krysten Schuler joined the U.S. House of Representatives Committee on Natural Resources for their June 25 subcommittee hearing on the subject. “Any meaningful strategies to combat CWD will require long-term approaches with sustained state and federal efforts," said Schuler. ⠀ Her recommendations included ✔ sustained fiscal support for state and federal wildlife agencies, as well as veterinary and wildlife diagnostic labs ✔ research funds to work toward new breakthroughs in treatment and prevention ✔ improved support from stakeholders up through their elected officials to raise the disease to a national level of prominence ⠀ #cornellvet #cornell #vetmed #veterinary #cwd #chronicwastingdisease #wildlife Maps created by @cornell_cwhl and image provided

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The disease has been spreading through deer, elk, and moose populations since 1981 (at least), when it was first identified in wild deer. While most populations still have low infection rates, they have grown to 10% or even 25% in others.

The more deer infected, the bigger risk to humans, warns a 2012 review in Emerging Infectious Diseases.

“The potential for interspecies CWD transmission (by cohabitating mammals) will only increase as the disease spreads and CWD prions continue to be shed into the environment.”

The CDC and WHO agree that transmission between species is possible, or one day could be, even though we have no evidence that it has already happened. Researchers are hoping to develop a test that could be used in the field, one that would tell hunters whether or not the meat they’re butchering is contaminated before they eat it.

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Members of the UWSP Student Chapter of #TheWildlifeSociety helped construct a Chronic Wasting Disease kiosk for the Stevens Point area. Students will now have the opportunity to assist local DNR with collecting CWD samples from harvested deer. . Thank you @uwsp_tws for allowing us to share! Want to see your student chapter featured? DM us @thewildlifesociety. . Repost: Through a partnership with the @wi_dnr and @uwsp_bha, the UWSP TWS was able to construct and deploy a #CWD kiosk for the Stevens Point area. Over the course of several weeks, student volunteers constructed the kiosk and were able to set it up before the gun opener this past weekend. With the kiosk, students will have the opportunity to monitor and check for heads and assist the DNR with lymph node extraction and sampling. The kiosk is located at Frank’s Hardware in Stevens Point. . . . . . . . . . . #Wisconsin #CWD #wildlifedisease #chronicwastingdisease #deer #wildlifebiology #wildlifebiologist #wildlifemanagement

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University of Minnesota scientists are working on that now, but in the meantime, if you hunt in an affected area, be aware of what the animals you kill looked and acted like prior to being shot. In all cases, you’re better off avoiding touching the internal organs as much as possible, particularly the brain and spinal cord.

If you’re worried, contact your local wildlife authority to get the animal tested before consuming it.

This is new territory, but as with most things that could cost you your life, better safe than sorry.