A new study says the spread of animal sicknesses such as Chronic Wasting Disease in deer may
happen more easily because of the way a protein binds to soil. Chuck Quirmbach reports:
Transcript
A new study says the spread of animal sicknesses such as Chronic Wasting Disease in deer may
happen more easily because of the way a protein binds to soil. Chuck Quirmbach reports:
Scientists have known that when an infected animal puts prions, or abnormal protein agents, in
soil the prions can stay alive for a long time. A study has looked at different types of common
soil minerals and found that a type of clay is an especially good binding agent for the prions.
University of Wisconsin researcher Judd Aiken says the link is so good that there’s a much higher
risk of the infection spreading when another animal grazes in the area:
“There was an enhancement of infectivity and we’re estimating roughly a 700-fold enhancement
of infectivity.”
Aiken says it might mean that government efforts to stop the spread of deadly animal brain
diseases like Chronic Wasting Disease in deer or scrapie in sheep may only be as effective as the
type of soil where the animals live.
Wildlife officials encourage hunters to help thin the population of CWD, but some hunters may be taking it beyond what is legal according to regulations. (Photo by Dr. Beth Williams, University of Wyoming, courtesy of CWD Alliance)
In states with deer herds affected by Chronic Wasting Disease, wildlife officials have
encouraged hunters to help them thin the population. But some wardens worry that
poachers are taking this as an invitation to bag game any way they can. Brian Bull
reports:
Transcript
In states with deer herds affected by Chronic Wasting Disease, wildlife officials have
encouraged hunters to help them thin the population. But some wardens worry that
poachers are taking this as an invitation to bag game any way they can. Brian Bull
reports:
It’s illegal to shoot deer at night, from vehicles, or while trespassing. But that’s something
Wisconsin game warden David Youngquist has seen recently. He monitors that state’s
Chronic Wasting Disease eradication zone. Youngquist says in that area, there are nearly
six times as many deer as is healthy for the herd:
“Our agency feels that if we can get deer numbers down, we can halt the disease. But we
still enforce the road hunting the same as we ever
have. We want hunting to be safe.”
Youngquist says poaching activities are on the rise, because some people think bagging a
deer is the main thing, whether it’s done legally or not. In some of these eradication
zones, a record number of citations have been handed out.
A new study finds that deer can spread a fatal brain wasting disease through saliva and blood. Rebecca Williams reports the researchers say this means no part of an infected animal should be considered safe to eat:
Transcript
A new study finds that deer can spread a fatal brain wasting disease through saliva and blood. Rebecca Williams reports the researchers say this means no part of an infected animal should be considered safe to eat:
Chronic wasting disease or CWD, affects deer, elk and moose, and it’s always fatal. CWD has been found in animals in 14 states and two Canadian provinces. Up until now, exactly how the disease spreads between animals has been a mystery.
Now a study in the journal Science shows evidence deer can spread CWD in their saliva and blood. Edward Hoover is the study’s lead author.
“No part of an infected animal is currently recommended to be consumed by people and these findings just underline that, that in addition to nervous system, the lymphoid system, we’d have to consider all parts certainly inappropriate for human consumption.”
Hoover says right now there’s no evidence people are susceptible to CWD, but he says scientists also can’t rule it out yet.
Chronic Wasting Disease is killing wild deer and elk. And it’s slowly spreading to new areas in North America. Right now, tests for the disease are done after the animals are dead, but researchers say they might be getting closer to a test that can be given to live animals. The GLRC’s Christina Shockley reports:
Transcript
Chronic Wasting Disease is killing wild deer and elk. And it’s slowly spreading to new areas
in North America. Right now, tests for the disease are done after the animals are dead,
but researchers say they might be getting closer to a test that can be given to live animals.
The GLRC’s Christina Shockley reports on what this might mean in the fight against the disease:
Chronic Wasting Disease, or CWD, causes deer and elk to waste away and die.
The disease is causing hunters and wildlife officials to worry about the
future of the wild deer population. Right now, testing a brain sample from a
dead animal is the sure-fire way to detect the infectious protiens, called prions, that
cause the disease.
Alan Young is a Veterinary Science professor at South Dakota State University.
He’s developing the new test.
“Our ultimate goal is basically to develop a test for infectivity in blood,
by taking a blood sample, and then analyzing for the presence of the infectious prion protein.”
Young says a blood test would let deer and elk farmers know if their herds are
infected before the animals die. He says the research could also lead to a cure for CWD.
A deer wasting away from Chronic Wasting Disease. (Photo courtesy of Michigan's Department of Natural Resources.)
An elk infected with Chronic Wasting Disease. (Photo courtesy of the Utah Division of Wildlife Resources.)
A disease that infects deer and elk has been alarming wildlife officials and hunters for years. But now it seems the disease could be more dangerous than previously thought. The Great Lakes Radio Consortium’s Christina Shockley reports:
Transcript
A disease that infects deer and elk has been alarming wildlife officials
and hunters for years, but now it seems the disease could be more
dangerous than previously thought. The Great Lakes Radio Consortium’s
Christina Shockley reports:
Chronic Wasting Disease, or CWD, affects the brain tissue of deer and
elk. Sponge-like holes form in the brains of sick animals. The deer
begin to waste away, become weak, and then die.
Since CWD was discovered in Colorado nearly forty years ago, wild deer
in nine other states have tested positive for the disease. Little is known
about CWD – including how to stop it.
What scientists do know is that the infectious proteins-called prions –
thought to cause CWD are found in the brain and spinal cord areas of
infected animals, but officials still don’t have the answer to the big
question.
Judd Aiken is a professor of Animal Health and Biomedical Sciences at
the University of Wisconsin.
“The ultimate question is whether venison from infected animals, CWD infected
deer, poses a risk to humans. Clearly the first question that needed to be
asked and addressed was whether there was infectivity in muscle.”
Recent findings say there is.
Researchers at the University of Kentucky injected muscle from an
infected deer into the brains of genetically altered mice. The mice
displayed signs of CWD. This is the first time the infectious proteins
blamed for CWD have been found in deer meat.
The finding raises questions about whether eating venison is safe.
Researchers including Aiken say the study is important, but has limits.
For example, he says it doesn’t replicate what would happen in real life.
Plus, he says it’s probably unlikely humans can even get CWD. He says
studies suggest it’s difficult for the disease to jump to other species. Still,
he urges caution. Hunters should get the meat tested before they eat deer
from an area where CWD has been found.
“I, in no way, can advocate the consumption of infected deer, and indeed,
I would suggest due to the limitations of the CW tests, I don’t advocate
the consumption of deer obtained from a CWD endemic area.”
Even if the test comes back negative, Aiken says a negative result isn’t
always accurate, and infected animals in the beginning stages of the
disease can look and act normal.
(Sound of sporting goods store)
John White is a deer hunter from Sheboygan, Wisconsin. He’s in the
hunting section of a nearby sporting goods store. White isn’t too
concerned about Chronic Wasting Disease.
“Not a whole lot of people are worried about it. I mean, when it first
came out, some people were a little leery about it and didn’t want to hunt
that year, but they kinda got over it. I’m not really worried about it being
in the meat at all, because by the time the test comes back I’ll probably
have the deer eaten already and then it’s already too late.”
State wildlife officials say… that’s not a good idea. They recommend that
if you hunt deer in areas where the disease has been found, get the deer
tested before eating it. That message hasn’t changed… since learning the
prions could be in the meat. Some argue… it should change.
John Stauber is with a government watchdog group in Wisconsin, and
is co-author of “Mad Cow USA: Could the Nightmare Happen Here?”
He says officials are keeping quiet about the risk of CWD so they don’t
lose revenue from hunting licenses.
A large portion of state conservation agency budgets are dependent on
fees from hunting licenses. He says all deer that die should be tested for
the disease. Stauber also says CWD is a major human health concern.
“The biggest risk might not be the people who would die from
eating venison, but rather, the people who would die from the
contamination of the blood supply. This is a problem that would unfold
not in days or months or years, but even over decades.”
Stauber says it’s just a matter of time before Chronic Wasting Disease
spreads to people… he says some might even have the disease already,
and not know it.
But researchers like Judd Aiken from the University of Wisconsin say
people shouldn’t over-react.
“People should be concerned, but I don’t want people to panic, either. If
you think you may have consumed venison from infected animals, I don’t
think it’s likely that you’ll ever develop a human prion disease.”
But, Aiken says there’s too much we don’t know about the disease, and
since studies can take years to complete, we might be in the dark for a
while longer.
New research shows the infectious material believed to cause Chronic Wasting Disease can be found in the meat of infected deer. Previously, it was thought that only the brain and central nervous system areas of deer or elk carried the fatal disease. The Great Lakes Radio Consortium’s Christina Shockley reports:
Transcript
New research shows the infectious material believed to cause Chronic
Wasting Disease can be found in the meat of infected animals.
Previously, it was thought that only the brain and central nervous system
areas of deer or elk carried the fatal disease. The Great Lakes Radio
Consortium’s Christina Shockley reports:
The authors of the study at the University of Kentucky say anyone
handling or eating deer infected with CWD may be inadvertently
exposed to the disease.
The research shows that for the first time the mutated proteins – called
prions – can be present in deer muscle.
Officials in states with CWD in wild deer say their message to hunters
won’t change:
Get deer tested for CWD, and don’t eat deer that test positive.
Jim Kazmierczak is Wisconsin’s State Public Health veterinarian.
“What this demonstrates is that the CWD agent does occur in deer
muscle. What it does not address is the question of human
susceptibility to Chronic Wasting Disease.”
Kazmierczak says it’s still unclear how – or if – Chronic Wasting Disease
could be transmitted to humans.
Officials say a new outbreak of Chronic Wasting Disease
could erupt after a fence was cut at an infected hunting preserve in Wisconsin. The Great Lakes Radio Consortium’s Christina Shockley
reports:
Transcript
Officials say a new outbreak of Chronic Wasting Disease could erupt after a fence was cut at an
infected hunting preserve in Wisconsin. The Great Lakes Radio Consortium’s Christina
Shockley reports:
Authorities say someone intentionally cut a hole in a perimeter fence at the preserve in central
Wisconsin. They say tracks indicate deer had gone in and out of the area through the hole…
before the owner saw it and notified the Department of Natural Resources.
Alan Crossley is with the Wisconsin DNR. He says officials shot deer around the preserve to try
to limit the chance the disease would spread to wild deer.
“We have to try to assess whether any deer escaped from that shooting pen. Then we’re going to
be meeting to talk about okay, should we try to do any additional shooting of deer in a larger area
around that pen.”
Crossley says it’s now even more important to monitor deer near the preserve in the years ahead.
He says it will take time to determine how their overall efforts to combat the disease are working.
So far, CWD has been found in the wild in ten states, including Wisconsin, New York and
Illinois.
Chronic wasting disease is affecting many captive deer, and has now been found in New York. Some question whether the disease has spread to wild deer. (Photo by Dr. Beth Williams, University of Wyoming, courtesy of CWD Alliance)
Chronic Wasting Disease has now been found in New York
and officials there are killing and testing hundreds of wild deer. They’re trying to keep the fatal brain disease from spreading to other animals. The Great Lakes Radio Consortium’s David Sommerstein reports:
Transcript
Chronic Wasting Disease has now been found in New York and officials there
are killing and testing hundreds of wild deer. They’re trying to keep the
fatal brain disease from spreading to other animals. The Great Lakes Radio
Consortium’s David Sommerstein reports:
Five captive deer in central New York tested positive for chronic wasting
disease earlier this month. It was the first time the neurological sickness
appeared in the Northeast.
Officials’ biggest concern is whether the ailment has spread to the wild. That’s why they’re killing and sampling up to 420 wild deer near where the
disease was detected.
Ward Stone is New York’s lead wildlife pathologist. He says those measures
are important, but they may not help in the long term.
“It would be nice if we could eradicate it in the next few weeks and it
doesn’t take hold, but I think it’s here to stay and I would not be
surprised to one day see it from Boston to Los Angeles.”
Chronic wasting disease has been found in 12 states, including Wisconsin and
Illinois. There’s no evidence it affects humans. Still, the Centers for
Disease Control and Prevention recommends against eating meat from infected
deer.
An elk showing symptoms of chronic wasting disease. CWD affects elk, white-tailed deer and mule deer. It's not known to be naturally transmissible to livestock or people. (Photo by Dr. Beth Williams, University of Wyoming, courtesy of CWD Alliance)
The Wisconsin DNR's Tia Kropf asks a hunter to show on a map where he got his deer. This helps the DNR plot the location of any CWD positive animals that are found. (Photo by Cherrie Nolden, courtesy of Wisconsin DNR)
Wisconsin DNR staffers Dave Linderud (left) and Kris Johansen registering deer at the Muscoda, Wisconsin DNR check station. (Photo courtesy of Dave Linderud)
Throughout most of the Great Lakes region,
there are huge numbers of white-tailed deer. Deer don’t have the natural predators that they once did… so states rely on hunters to manage the deer herds. Recently, that’s become even more important with the discovery of a fatal disease. The Great Lakes Radio Consortium’s Rebecca Williams reports there’s extra pressure on hunters to keep the disease from spreading:
Transcript
Throughout most of the Midwest/Great Lakes region, there are huge numbers of
white-tailed deer. Deer don’t have the natural predators that they once did…
so states rely on hunters to manage the deer herds. Recently, that’s become even
more important with the discovery of a fatal disease. The Great Lakes Radio Consortium’s
Rebecca Williams reports there’s extra pressure on hunters to keep the disease from spreading:
“How are you today? Successful morning, or are these from yesterday? This
morning… oh okay…”
Hunters are bringing their deer into a check station. Department of Natural Resources staff
determine the age of the deer by looking at their teeth. If it’s an adult deer, a technician
saws the head off so brain tissue and lymph nodes can be tested for chronic wasting disease.
(sound of deer head being cut off)
Chronic wasting disease, or CWD, affects white-tailed deer, mule deer and elk. It’s always
fatal. So far, there’s no evidence that CWD can hurt people or livestock. For now, most wildlife
managers are just worried about the health of the deer herds.
Western states such as Colorado and Wyoming have been dealing with CWD for decades. Wisconsin
found the disease in wild deer in early 2002. Illinois found the disease later the same year.
So far, it hasn’t shown up in wild deer in neighboring states, such as Indiana, Michigan or
Minnesota.
Wisconsin has a lot of deer crowded into a relatively small space, and that worries state
officials. Tami Ryan is a wildlife supervisor with the Wisconsin Department of Natural Resources.
“Some of the genetic research that’s been done to date on Wisconsin deer, they are not
resistant to CWD. It could be severely detrimental to the herd, which is why we feel so
strongly about trying to contain the disease where it exists and prevent it from spreading.”
Wisconsin’s attempting what state officials call aggressive herd reduction. At first, the
state wanted to kill all the deer in the heart of the disease eradication zone. Now, the state
wants to kill five of every six deer in those zones. That means reducing the deer to fewer than
five per square mile.
The Department of Natural Resources is trying to do this by making hunting seasons longer
and handing out more permits. In the disease eradication zones, people can hunt on private
land all fall and all winter – September to March.
Many hunters say they like the opportunity to take a few extra deer. Mike Snodgrass hunts
regularly in one of the areas where the state’s trying to reduce the herd.
“From just being out and observing the deer, there’s a huge number of deer out in the woods.
I’ll do my part, I enjoy the venison, and so I’ll take a couple of does out, no problem.”
The Department of Natural Resources says hunter participation is crucial for controlling
chronic wasting disease. That’s because the state doesn’t have nearly enough wardens to kill
all those deer.
State officials worried at first that CWD would turn hunters off from the sport. But from some
recent surveys, it’s been clear that most hunters say they understand the problem and they still
want to hunt where they’ve hunted every year – whether or not there are sick animals in those
areas.
The state’s also reaching out to private landowners. Most of the land in the disease zones is
privately owned. The state’s encouraging landowners to open up their land to more hunters.
Mike Albert is a landowner who hunts. He owns 275 acres near where the first three infected
wild deer were found. Albert says he’s hesitant to open up his land to strangers, but he does
let friends and family hunt on his land. He says something has to be done about chronic wasting
disease, but he says he’s afraid the state’s going too far.
“It’s not that I don’t feel a responsibility to help. As an ethical hunter when you’re asked to
just blatantly shoot every deer you see no matter how, it’s hard to overcome that. They’re asking
us to totally devastate our herd, ruin our tradition, and do all this stuff before we know for
sure whether it’s the right thing to do.”
Albert says more of the effort should be focused on understanding the disease before acting.
Researchers are still asking many questions about the disease itself. It’s still not known
exactly how the disease is transmitted.
Beth Williams is a veterinarian at the University of Wyoming. She’s also a leading expert on
CWD. Williams says there aren’t any proven methods for stopping CWD. She says killing off
much of the deer herd is controversial, but the state’s options are limited.
“I think it was a good idea for Wisconsin to see whether or not taking fairly radical steps
like they have to do their herd reduction, whether or not that might stop CWD. The alternative
is, based on everything that we know, if you don’t try and do something, the disease is then
going to spread.”
Williams says it’ll be years before anyone can tell whether reducing the deer herds
will help. But many people agree chronic wasting disease needs to be stopped as soon
as possible, before it spreads to deer herds in neighboring states.
For the Great Lakes Radio Consortium, I’m Rebecca Williams.
Wildlife officials in the Midwest are battling the appearance of a deadly illness found in elk and deer. Called chronic wasting disease, or CWD, this ailment attacks an animal’s brain, slowly eating away healthy tissue. Several captive elk herds in the western U.S. and Canada have been infected with chronic wasting disease. Those herds have now been quarantined, but not before other animals from those herds were sold to farmers in 21 states nationwide, including several in the Midwest. The Great Lakes Radio Consortium’s Todd Melby has this first report of a two-part series:
Transcript
Wildlife officials in the Midwest are battling the appearance of a deadly illness found in elk and deer. Called chronic wasting disease, or CWD, this ailment attacks an animal’s brain, slowly eating away healthy tissue. Several captive elk herds in the western U.S. and Canada have been infected with chronic wasting disease. Those herds have now been quarantined, but not before other animals from those herds were sold to farmers in 21 states nationwide, including several in the Great Lakes region. The Great Lakes Radio Consortium’s Todd Melby reports.
Chronic wasting disease is a neurological disorder. That means it affects the nervous system of elk and deer. It’s related to a number of other conditions, including scrapies in sheep and mad cow disease. Humans can also contract something similar — it’s called Creutzfeldt-Jakob disease.
All these conditions are related — and that’s making some health officials nervous. That’s because at least one, mad cow, can be transferred to humans. Dennis Stauffer is a spokesman for the Minnesota Department of Natural Resources. He says now more and more people are also keeping an eye on CWD.
“It’s been called the mad cow disease of deer. It is certainly similar biologically. There are also some important differences. Unlike mad cow disease, or CWD as we call it, we don’t yet have any evidence it is transmittable to humans. So that particular health risk is not confirmed.”
But that doesn’t stop people from worrying.
In the 1990s, mad cow disease in Great Britain triggered a similar ailment in humans, eventually killing dozens of people. But public health officials downplayed that possibility, leading to less vigilance in eliminating mad cow. Some people now say the same thing is happening here with CWD. Sheldon Rampton is the author of “Mad Cow U.S.A.”
“You are getting the same pattern of reassurances. The same pattern of government authorities and government scientists coming forward and not quite saying there is no danger, but saying they don’t see any evidence of danger. And then saying that in such a way that the public is led to believe that absence of evidence is evidence of absence.”
One of the problems is, little is known about the disease. Kris Petrini is a veterinarian with the Minnesota Board of Animal Health.
“We don’t know exactly what the incubation period is. We don’t know the youngest possible time an animal can get infected. The testing itself, right now, the only test we have that we can do is the animal has to be sacrificed and the brain tested.”
The outward signs of CWD aren’t exhibited until death is near. Again, Dennis Stauffer of the Minnesota DNR.
“Well, if you were to see a picture of one of these animals, they would be stumbling around, they would look wasted away. In advance stages, they would look disoriented, they would tend not to fear humans. They would look very, very sick and it would be very obvious that they are sick animals.”
Since learning that 36 elk from CWD-infected herds in Colorado and Canada were imported to Minnesota, state officials have set up a voluntary CWD surveillance program. All herds with exposed animals are participating in the program. Of the elk tested for CWD so far, none have had CWD.
(sound from Spooner, Wisconsin deer testing station: Cars on nearby two-lane highway.)
In neighboring Wisconsin, state officials are aggressively testing for CWD. On the opening weekend of deer hunting season, veterinarians took hundreds of brain samples from dead animals at locations throughout the state. In previous years, such efforts turned up no cases of CWD in the wild deer population, just like Minnesota. Ken Jonas is a wildlife biologist with the Wisconsin Department of Natural Resources.
“Right now, I’m not too concerned. If I were in Colorado or perhaps Wyoming or a state that was near to a chronic infection, I would be very concerned.”
While Kris Petrini, the Minnesota veterinarian, understands CWD hasn’t made it into the wild deer population, she says she wouldn’t be surprised to find it among the captive elk population in the state.
“No, not completely. Not with the number of elk we have and the amount of trading that goes on in the industry, I think it is highly possible that we will find chronic wasting disease.”
Six western states are home to elk herds with CWD infections. Elk farmers in another 15 states — including Minnesota, Wisconsin, Illinois, Indiana, Michigan, Ohio and Pennsylvania — own animals from the original infected herds. So far, tests haven’t turned up any traces of CWD in herds with exposed animals in those states.
For the Great Lakes Radio Consortium, I’m Todd Melby in Minneapolis.
