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Wisconsin is requesting millions of dollars from the Agriculture Dept. (USDA) to help fight chronic wasting disease, the transmissible encephalopathy (TSE) infecting North American deer and elk.. 

The state is home to a specialized livestock industry which sells ranched animals for breeding and slaughter.  The owners of an estimated 20,000 elk and deer are facing an economic catastrophe and will be seeking compensation if their animals are killed to halt the spread of the disease. 

The state is also concerned about its deer-hunting industry Brings in $32 million in license fees annually and $1.3 billion in related services.

Worse yet, is the concern that CWD could infect cows and affect the state's $20 billion dairy industry.  So far, that has not been known to happen.  CWD is a prion (an abnormal protein) disease related to bovine spongeiform encephalopathy (BSE) or "mad cow" disease.  BSE is thought to have originated from incorporating dead sheep in fodder for cows.  Sheep have long suffered from scrapie, another TSE.  Transference of TSEs between species is not usual, but it has been conclusively demonstrated between cows and penned mink, for instance.

Another concern is that the already too large deer herd of 1.5 million animals will grow even larger if hunters no longer want to kill them.  "We are absolutely dependent on hunters to help us manage our deer population," whines state wildlife veterinarian Dr Julie Langenberg revealing that she doesn't understand deer population determinants.  Hunters kill 460,000 deer a year, but hunting accelerates breeding with the result that the losses are replenished--usually with interest--when fawns are born in the spring.  Compensation for crop damage costs the state $1.5 million a year.  Automobile accidents caused by deer result in claims approaching $1 billion a year nationally.  Wisconsin has 50,000 such accidents annually.

Quoting directly from Ginsburgs article: "CWD, like mad cow, is a transmissible spongiform encephalopathy (TSE)--also known as a prion disease. A prion is a normal protein molecule that folds a particular way in healthy animals. But "rogue" prions fold differently. They act like seed crystals, creating a pattern that other prions mimic. Over a period of months, years, or decades, these misshapen prions lead to brain lesions and death.

"Can CWD infect humans? There has only been one study. Scientists at Rocky Mountain Laboratories in Hamilton, Mont., found that CWD prions were able to convert human prions at a very low rate--about the same rate that mad cow converts human prions. Later this year, the first major CWD study involving nonhuman primates is scheduled to begin at the National Prion Disease Pathology Surveillance Center in Cleveland.

"CWD has never been linked to a case of Creuzfeldt-Jakob disease (CJD), the human TSE. Recently, a team led by Dr. Ermias Belay at the Centers for Disease Control Prevention in Atlanta investigated three cases involving venison-eating victims under age 30. CWD was ruled out, though no cause was determined. Belay points out that in 85% of CJD cases the cause is never found. Further complicating the picture, only 40% of suspected CJD cases in the U.S. are autopsied--which is the only sure way to make a diagnosis.
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But the fear alone of CWD could have far-reaching effects. There are close to 12 million deer and elk hunters in the U.S., says the Fish Wildlife Service. Although there are no records of how many animals they kill, 8 million to 10 million is a conservative estimate. There are also no records on how much hunter-killed venison is consumed, since it isn't USDA-inspected. "Venison is social meat here. It's the stuff used for football game chili and put into sausages that are given as Christmas gifts. It's a prize shared with family and friends," explains Wisconsinite Kathy Lee, whose husband John is an avid bow hunter. "Everybody's scared," she says, and many hunters are clearing their freezers.

"While contaminated livestock feed is the agent of infection in mad cow disease, researchers suspect that CWD spreads through physical contact such as "nose kissing," or browsing in forage contaminated by infected urine and feces. There is evidence that prions--which can withstand freezing as well as temperatures of 1,000F--can survive in the ground. "I think there are analogies between TSEs and the AIDS virus," notes John Stauber, co-author of Mad Cow USA and a Madison resident. "People weren't able to grasp the immensity of a type of infection that broke so many rules. This is a great example of a situation that can be prevented if it's caught in time."
It has been more than 30 years since the first cases of emaciated, slobbering mule deer were observed in a wildlife testing facility pen in Colorado. In the wild, about 1% of elk and 5% of mule deer are thought to have CWD in an 8,500-square-mile area of Colorado and Wyoming.
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Farmed elk may have picked up the disease from their wild cousins--fence-jumping and through-the-fence nose-kissing are common. But elk farming has played a key role. A contact disease is more dangerous when animals are kept at close quarters. And given such a long, symptom-free incubation period, elk that looked healthy but were in fact sick were shipped all over the U.S. and Canada. Now, states such as Texas--which has a multibillion-dollar game farm industry--are banning imports. It could be too late. "It became clear to me that it didn't matter that we were 900 miles away from the endemic area," says Langenberg, explaining why Wisconsin became one of the first states to test wild deer three years ago.
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The fight to contain CWD has already been costly. Last year, Canada spent millions to slaughter more than 7,000 elk from several suspect farms. In January, an elk on yet another farm tested positive. CWD has also popped up in recent months on farms or in the wild in South Dakota, Kansas, Nebraska, and Colorado--where 1,500 farmed elk were incinerated. The USDA has released funds to reimburse producers as much as $3,000 per head. An additional 4,500 wild elk and deer near Fort Collins, Co., will be culled shortly.

"Meanwhile, Langenberg points to a map on a computer screen. There have been at least 20 escapes from whitetail farms across Wisconsin over the past two years. And unlike Bessie the cow, when Bambi makes a break for it, he can easily fade into forest, perhaps carrying a deadly disease. No one may ever know how CWD got into Wisconsin. Langenberg just hopes they'll be able to stamp it out."

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