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Brain disease a slow goodbye
His illness at center of global debate

Doug McEwen's decline began in the summer of 1998 as something so benign you would have sworn it was just a touch of forgetfulness. Now, six months later, McEwen and his wife, Tracie, find themselves in the center of a national debate about "mad cow" disease and the government's role in preventing it.

Tracie McEwen also finds herself facing tough decisions, as dueling scientists lobby to be the recipient of her husband's brain once he dies.In early January, Tracie McEwen joined several activist groups -- including the Center for Food Safety and the Center for Media and Democracy -- as a petitioner in two legal actions demanding changes in the way the government monitors and prevents mad cow disease and related disorders, including a human version known as CJD, short for Creutzfeldt-Jakob disease.

"Terminally ill Utah hunter, age 30, could be the first victim of U.S. 'mad deer' disease," read the headline of a press release issued last week from the Center for Food Safety in Washington, D.C.

Like everything surrounding mad cow disease and its medical cousins, the case of Doug McEwen reveals how confusing, controversial and provocative the subject is. Can CJD be caused by the food we eat? Does that food include deer meat? Are cases like this the beginning of a world epidemic, or are food activists using scare tactics?

The issues are further confounded by a string of initials and disease names: CJD, CWD, BSE, TSE, mad cow, mad deer. What they have in common is a set of similar and terrifying neurological symptoms, brain tissue that looks like sponge (hence the term "spongiform encephalopathy," the medical term for the diseases), and a disease course that ends, always in death.

The disease can incubate for decades before symptoms appear. Diagnosis is difficult, and reporting of the disease has been lax, so it's not even clear how many cases of CJD there are in the United States. Perhaps most frightening, the disease agent -- a deviant form of protein called a prion -- can't be killed by radiation, freezing or sterilization.

In England, a "new variant" form of CJD has been linked to bovine spongiform encephalopathy, also known as mad cow disease. So far 40 people have been diagnosed with BSE, which many scientists believe came from eating British beef. But this is a point of contention, too. Stanley Prusiner, who received the 1997 Nobel Prize in medicine for his work on prions, is among those who isn't totally convinced.

The link between human disease and "mad deer" disease -- that is, between CJD and CWD (chronic wasting disease) -- is even more unclear.

Six percent of deer in northeastern Colorado and southeastern Wyoming have been found to have chronic wasting disease. If it turns out that Doug McEwen has a form of CJD similar to this "mad deer" disease, his would be the first confirmed case. "If there's going to be a canary in the coal mine," says one researcher, "it will be McEwen."

But it may take years to find out.

The beginning

Doug McEwen was 29 when he developed his first vague symptoms of CJD. Tracie would call Doug at work and tell him to bring home some milk and he'd forget to do it and then say he didn't even remember her call. That was in early July last year. Then, in late July, Doug went to Idaho on a business trip.

As usual, Doug would call home every night to tell Tracie and their two daughters good night. One night, though, Tracie didn't get a call till 11.

"I couldn't remember our phone number," Doug told her.

"Why didn't you call directory assistance?" she asked.

"I can't remember how to spell my last name," he said. By August, when he decided to quit his job, he couldn't write the letter of resignation because he couldn't remember how to turn on the computer.

At first his doctor suspected depression or stress, and Doug was sent to a psychiatrist. In mid-September, on the eve of Doug's first appointment with a neurologist, the McEwens happened to see Kearns resident Mel Steiger being interviewed on TV about his wife, Ellie, who died of CJD last March. Ellie's symptoms -- the memory loss that proceeded eventually to Ellie's inability to recognize her own family -- sounded distressingly familiar.

"When we got to the neurologist the next day, I still remember him saying 'I know what you are worrying about, but he is too young and this disease is too rare,' " Tracie recalls in a letter posted on CJD Voice, a Web site for family members of people with the disease. CJD generally shows up in people older than 50.

When testing of McEwen pointed to the possibility that it was CJD, doctors decided to send tissue of McEwen's brain to researchers in Ohio. The biopsy confirmed the CJD diagnosis.

Currently, scientists at the National Institutes of Health are testing Doug's DNA to determine if he has a genetic flaw that caused the disease. Ten percent of CJD cases are believed to be inherited. If Doug falls into this category, his disease will be an open-and-shut case.

But if he didn't inherit the mutated gene, the case gets murkier. Like other CJD cases, Doug's makes clear how much we still don't know about the disease.

About 1 percent of CJD cases are believed to be "iatrogenic," that is resulting from medical procedures, including corneal transplants, contaminated brain electrodes and growth hormones. Doug has had none of these. (A couple of CJD cases have raised questions about dental procedures, but there has been no evidence to date that can prove a link.)

CJD cases that aren't genetic and aren't iatrogenic are labeled "sporadic." But, although the name implies that the disease appears randomly -- the estimate is that one in a million people for some reason develop mutations in their brain cells -- it may be that we just don't yet understand what causes CJD, says Thomas Pringle, a microbiologist and staff member of the Sperling Biomedical Foundation in Eugene, Ore.

Eating infected meat could be one of those causes. In Doug's case, all that's known for sure right now is that he is not suffering from "new variant CJD," the English version that may be connected to English beef. But what about deer meat?

Hunting connection?

According to Tracie McEwen, Doug has been eating deer, elk and antelope since he was a little boy; as a couple, they ate game two or three times a month in the fall and winter. As a hunter, he also handled deer carcasses.

Tracie's gut feeling is that Doug did not get CJD from game, especially since she doesn't think he or his brother ever hunted in northeastern Colorado or southeastern Wyoming. But other people think Doug could end up being the first link between CWD and CJD.

What we do know, says Pringle, is that epidemiological studies have identified several "risk factors" for CJD -- that is, some things that many of the cases had in common -- and one of those was a diet of "wild game." It "doesn't prove causation," explains Pringle, but it is a "correlation."

The Utah Department of Health is investigating Doug McEwen's illness, as well as the seven other cases of CJD in Utah in 1998. Meanwhile, the official position is that "there is nothing right now to link his illness to eating wild meat" or handling wild meat, says epidemiologist Gerrie Dowdle, manager of the department's communicable disease control program.

To suggest that Doug's diet may have caused his disease is "purely assumption," says Dowdle. "We haven't heard of any cases of humans getting it from elk or deer. That's not to say it's not possible," she adds.

Can CWD be spread to humans? Scientists at the Rocky Mountain Labs in Hamilton, Mont., are conducting tests that may provide some part of the answer, according to researcher Byron Caughey.

Scientists don't even know how deer get CWD. Did it first appear as a sporadic mutation and then get spread to other deer? Did deer get it from sheep, who can have a similar disease known as scrapie?

At the Center for Food Safety, Ronnie Cummings's theory is that the disease was spread to deer at central deer-feeding stations, through deer feed that includes rendered animal protein -- that is, ground up meat that might have come from other diseased animals.

(Feeding animals to animals is believed by many to be the cause of the spread of other forms of the disease, including the bovine version. The Center for Food Safety's petition filed Jan. 7 called on the FDA to "close serious loopholes in U.S. animal-feed regulations which currently allow types of cannibalistic feeding practices known to cause and spread 'mad cow' type disease." These include "feeding pigs to pigs, pigs to cattle and cattle blood products to calves.")

If a deer has CWD, would a hunter be able to tell? "We don't know if animals can be infectious without showing symptoms," says Beth Williams, professor of veterinary science at the University of Wyoming and a lead researcher in CWD. "But we can detect the abnormal protein in the brain of animals before they get sick." Are hunters shooting deer whose initial symptoms might only include a clumsiness that makes shooting them easier?

According to Utah state veterinarian Michael Marshall, animal health officials in Utah are "monitoring carefully" for chronic wasting disease at privately owned elk farms, "and have found no occurrence whatsoever." In addition, some 150 Utah deer brains have been collected and sent to the state veterinary diagnostic laboratory at Utah State University. So far all 80 tested have proved negative, he says.

More questions than answers

Doug McEwen's brain may provide some answers about CJD and perhaps even its connection to "mad deer" disease. And that means that several different laboratories will be vying to get their gloved hands on his brain once he dies.

"We want to make sure reliable people get it," says Cummings of the Center for Food Safety. "We don't trust Prusiner and (Paul) Brown (of the National Institutes of Health). We think they're capable of repressing results."

But it could take a couple of years for the brain tissue to yield answers. First researchers have to determine what the strain of CWD would look like once it was transmitted to humans.

At this point, Tracie McEwen isn't sure she wants to give her husband's brain away. An autopsy would not only mean no open casket, it would also mean Doug might not be embalmed.

This past weekend, 220 members of the Utah Funeral Directors Association met in St. George; high on their list of agenda items was what to do about CJD. The association has issued no guidelines, says UFDA president Kurt Soffe, but is trying to educate its members about the dangers of the disease.

One study that strikes Soffe as significant: Prions placed on an inanimate object were found, three years later, to still be infectious. The inanimate objects mortuary workers would be concerned with, of course, include embalming tables and instruments. Cleaning and sterilizing equipment can reduce the number of prions but don't seem to totally eliminate them. It is not known how much infectious material is needed to cause disease.

In addition, it turns out, the formaldehyde used by embalmers makes prions even more durable, hardening the encasement around the protein.

What Soffe and other morticians also worry about are the cases of undiagnosed CJD. The disease is difficult to diagnose without a brain biopsy or autopsy -- and CJD has symptoms nearly identical to Alzheimer's. There is evidence that some cases of Alzheimer's have been misdiagnosed CJD cases. Often cited is a Yale study that found that six of 46 people who reportedly died from Alzheimer's actually had CJD.

A new study of CJD just reported last week in the British journal "Lancet" raises even more troubling questions. Researchers in Great Britain reported that CJD prions could be found in tonsil and appendix tissue.

"Although the concentration of infectious prions is expected to be lower in these tissues than in the brain, the opportunity for iatrogenic transmission from appendicectomies or tonsillectomies should not be overlooked. . . . Perhaps the adoption of universal precautions, based on the assumption that the material is infectious until proven otherwise, would be the most prudent course."

There are still more questions than answers. In the meantime, Tracie McEwen gets calls from well-meaning strangers who insist that they know just the right herb/magnet/tonic to make Doug well. One woman even wanted to send breast milk.

Doug McEwen continues to get worse, almost daily. He has to work hard to remember how to use the stairs. His speech has become garbled; he has begun having seizures and has become incontinent.

Most disturbing, he will often withdraw from his family, refusing to even look at 8-year-old Sharon when she climbs on his lap.

"This is the worst thing I have ever seen," says Tracie McEwen. "I wouldn't wish it on my worst enemy."