Mad Cow Disease

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Dangerous cuts of meat
Tougher ban on donors
Picking up other people's dead animals.
Turning cattle into cannibals
Detecting mad cow
CJD gaining attention

ARTICLE from THE AKRON BEACON JOURNAL, 6-3-01, BY JANE SNOW and Mary Ethridge, Beacon Journal staff writers

``First comes the pain and crying. Then the hallucinations and screaming. As the fatal disease progresses, the victim loses all motion and all reason. The brain becomes riddled with holes.

When death comes, it is a blessing.

And scientists believe this lethal new disease is contracted by doing something incredibly ordinary -- eating beef ...

Variant Creutzfeldt-Jacob disease (vCJD) has been linked to eating beef from cattle infected with bovine spongiform encephalopathy -- mad cow disease.

To keep mad cow out of the United States, federal officials in 1997 banned the practice of adding to cattle feed protein supplements made from dead ruminant animals -- animals with four stomachs -- such as cows, sheep, goats and deer.

But it's highly likely that these protein supplements are getting into U.S. cattle feed, because enforcement of the ban has been slow.

``The FDA recognizes that as our greatest area of vulnerability,'' Stephen Sundlof, director of the Food and Drug Administration's Center for Veterinary Medicine, told the Akron Beacon Journal.

And there are other weaknesses in the fire wall the United States has built to stop mad cow from getting to this country and infecting beef eaters.

Cow brains, which, along with retina and spinal-cord tissue, are thought to be the most infectious parts of tainted animals, are still sold for human consumption in this country.

Techniques used at U.S. slaughterhouses fail to prevent spinal-cord tissue from contaminating equipment and then being mixed with ground meat.

Pigs are exempted from the feed ban and are allowed to eat meat and bone meal made from dead cows and from sheep infected with scrapie, a disease related to mad cow. These dead pigs can then be turned into protein supplements that can be fed to cattle.

Calves are allowed to eat feed sprayed with dried cattle blood. Although scientists have no evidence that the mutated proteins -- the hallmarks of mad cow and vCJD -- can be transmitted through blood, the possibility has prompted restrictions on human blood donors ...

Only a tiny number of cattle slaughtered in the United States are tested for mad cow -- not enough for experts to be certain that the disease is not here.

Mad cow has sent beef sales in Europe plunging, and some Americans are wondering whether they, too, should give up their beloved hamburgers ...

Consumer advocates ... say the government has moved too slowly, and they suggest that mad cow may already be in the United States, silently incubating ...

Mad cow disease, the scourge of Europe, has spread to 16 countries, including across the Atlantic to Canada. It has decimated the European cattle industry and left 91 people -- 87 in Britain, three in France and one in Ireland -- dead.

It was first identified as a new and deadly disease in 1986 when farmers in far-flung hamlets in Britain noticed that some of their cows were acting strangely -- drooling, losing weight, stumbling and eventually becoming aggressive toward other members of the herd. The wild behavior always ended in death.

At the height of Britain's mad cow crisis in January 1993, new cases among cattle were being reported at the rate of 1,000 per week. More than 180,000 head of cattle in Great Britain have been stricken.

The cause of this strange disease was a mystery until 1989, when scientists linked feeding practices to its spread. Although research continues into other possible forms of transmission, such as infection from contaminated soil, it is believed that most cases of mad cow worldwide can be traced to feeding cattle meat and bone meal as a protein supplement.

In 1996, researchers at the Institute for Animal Health in Edinburgh, Scotland, presented evidence linking vCJD to eating meat from cattle infected with mad cow disease.

Creutzfeldt-Jakob (pronounced ``krootz-feld yah-kub'') disease had been around for a long time, but it afflicted mostly older people, aged 50 to 75. The new variant mimicked the symptoms of Creutzfeldt-Jakob, but its victims were as young as 20.

Both mad cow and CreutzfeldtJakob are transmissible spongiform encephalopathies -- diseases in which abnormally shaped proteins called prions ravage the brain and the body's central nervous system ...

As discoveries about mad cow were being made in Europe, U.S. officials moved to try to block the disease.

In 1989, the importation from Britain of live cows, feed made from ruminant animals and beef products was banned by the U.S. Department of Agriculture. The following year, the USDA began destroying and testing cattle that showed signs of neurological problems.

A USDA ban on importing live cows, sheep and goats and on importing ruminant feed was expanded to a ban on such imports from most European countries in 1997. But that feed ban may have come too late. U.S. cattle that ate imported feed may be alive today and infected, because symptoms of mad cow do not appear for two to eight years.

Also in 1997, the FDA issued new rules prohibiting protein supplements made from dead cows and sheep from being added to cattle feed in the United States ...

The practice of rendering animals appears to be at the heart of the spread of mad cow. In 1980, the British rendering industry banned the use of certain chemicals and lowered the cooking temperature used in the process. It is thought that these two shifts in procedure allowed mad cow disease to flourish undetected.

During rendering, carcasses that have been stripped of their edible parts are ground up and then decomposed in large vats by boiling under extremely high pressure. The process produces a slurry of protein under a layer of fat called tallow. That slurry is dried into a meat and bone meal product.

After four years of inspections, a number of U.S. feed mills and renderers still aren't in full compliance with the FDA rules.

As recently as a month ago, the FDA was sending warning letters to Ohio renderers and feed mills about violations. Some companies were making both ruminant and nonruminant products in the same vats without washing them in between, according to the FDA letters. Other companies weren't bothering to affix warning labels to their ruminant feed as the law requires.

The FDA estimates that since the ban on adding ruminant protein to cattle feed was instituted, 10,489 mills and renderers nationwide have been visited by inspectors. Most of the 834 firms that failed the initial inspections have been revisited, and according to the FDA, all but 40 of them eventually passed.

In Ohio, 475 rendering plants and feed mills have been inspected since 1998, and 138, or 29 percent, were found not to be in compliance with some aspect of the ban, according to FDA records.

However, many firms have not been inspected. The FDA estimates that 300 licensed and 2,000 legal unlicensed renderers and feed mills still have to be visited.

``We have to make the assumption that some cattle may be getting ruminant meat and bone meal,'' said the FDA's Sundlof.

In at least one instance, ruminant protein did get into U.S. cattle feed. In January [2001], Purina Mills of Texas announced that some ruminant feed was mistakenly fed to 1,200 cows. Purina agreed to buy all the affected cattle and then destroy them.

The potential for this type of problem, consumer activists say, points out the need for FDA regulations to be expanded. They want a complete ban on animal byproducts in feed for food animals -- and not just because of possible mistakes such as the one Purina made.

``Our view is, so far, we appear to be lucky,'' said Jean Halloran, director of the Consumer Policy Institute, the consumer lobbying arm of New York publisher Consumers Union. ``In our opinion, we don't want to rely on luck for the future.''

The FDA feed ban applies only to ruminants. Protein supplements made from those animals can't be put into feed for those animals.

But protein supplements made from ruminants can be added to feed for other animals, such as pigs. And pigs can be made into protein supplements for cattle feed.

Halloran said pigs should not be allowed to eat protein supplements made from sheep infected with scrapie and from deer and elk that have died from chronic wasting disease -- two mad cow-like disorders that are in the United States.

``We allow the pigs to be fed back to cows,'' she said.

Although mad cow disease has not been found in pigs in Europe, one study has shown that pigs are capable of contracting the disease.

In this National Institutes of Health study referred to by Halloran, 10 pigs received injections of highly infectious material directly into the brain and stomach. Only one pig developed a neurological disease.

But the FDA's Sundlof said the government is not considering adding swine to the feed ban.

``There's no natural case of a pig ever getting a TSE,'' or transmissible spongiform encephalopathy, Sundlof said.

Halloran also is worried about dried cattle blood being exempted from the feed rule. Calves are commonly fed dried blood as a protein supplement.

``We say that people who have lived in Britain can't donate blood,'' Halloran said. ``But when it comes to animal feed, it's OK.'' ...

The [FDA] is seeking public input on whether dried-blood supplements should be fed to calves, on whether discarded food from restaurants should be fed to cattle, and on whether all feed mills and renderers should be licensed by the FDA.

``We're going to look at the entire scope of the (feed ban) rule and determine if there are other areas that need to be firmed up,'' Sundlof said.

But new rules take time to enact. Once they're proposed, getting them in place will take a minimum of a year, said Dan McChesney, director of the FDA's Office of Surveillance and Compliance.

In the past few years, government officials have been working with the meat industry to prevent brain tissue from cows from mingling with meat that goes to consumers. Yet consumers are still able to buy cow brains for sauteing or making into sandwiches ...

Selling beef brains is legal because mad cow disease has not been found in any animal in the United States, said Paul Brown, senior researcher at the Center for Central Nervous System Disorders at the National Institutes of Health.

``If mad cow were here, those people would be dead,'' Brown said.

Or at least dying. According to researchers, vCJD has an incubation period of 10 to 20 years before symptoms appear ...

Carolyn Smith De Waal, director of food safety for the Center for Science in the Public Interest, a Washington, D.C.-based consumer lobbying group, said slaughtering techniques need to be tightened ... to prevent mixing brain and spinal-cord tissue with beef that will go to consumers.

The center plans to petition the USDA to ban the use of the Advanced Meat Recovery Machine, a piece of slaughterhouse equipment that strips meat from cattle carcasses.

Riley said that in 1998, at the order of the USDA, meat institute members began removing the spinal cords from cows before they were processed in the meat recovery machine.

But De Waal said enforcement of this order is lax and the procedure is imperfect. Tests have shown that spinal-cord tissue is still present in some ground meat, De Waal said.

``We still need more protections to prevent mad cow disease from entering the human food supply,'' De Waal said ...

Although government officials repeatedly stress that mad cow disease is not present in the United States, others aren't nearly so sure.

The Consumer Policy Institute's Halloran said more cattle need to be tested for the disease.

Although the USDA initiated a testing program in 1990, only cattle with obvious symptoms of neurological disease have been targeted -- and not all of them are tested, she said. Live animals cannot be tested; the only way to detect mad cow is to examine slices of the dead animal's brain.

``We don't have adequate surveillance of cattle to say conclusively that there's no problem here,'' she said.

Pierluigi Gambetti, director of the National Prion Pathology Surveillance Center at Case Western Reserve University in Cleveland, agrees.

Of the 37 million cattle slaughtered in the United States each year, an average of just 1,000 have been tested, Gambetti said. This year, 2,600 cattle are scheduled for testing.

``That's just too small,'' Gambetti said. ``The only way to lessen the panic is to do more testing. . . . There's always less concern when you know the size. When you know the size of the problem, you now have the ability to put together a plan, a remedy.''

In the meantime, some feed mills and renderers remain uninspected. Protein supplement made from pigs is being fed to cattle. So is cow blood. People are eating cow brains and meat with spinal cord tissue in it. Medical supplements made from European cattle are sitting on store shelves ... ''

Beacon Journal medical writer Tracy Wheeler contributed to this report.

Jane Snow is the Beacon Journal's food writer. She can be reached jsnow@thebeaconjournal.com.

Mary Ethridge can be reached at methridge@thebeaconjournal.com

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ARTICLE from THE AKRON BEACON JOURNAL, 6-3-01, BY JANE SNOW, Beacon Journal food writer

``Experts say certain cuts of meat could pose greater dangers

European hamburgers were among the first foods to go. Beef sausages, T-bone steaks and sauteed beef brains are now taboo, too.

Across the Atlantic, mad cow disease has cut beef sales by 30 percent, changed restaurant menus and increased the price of seafood and leather.

And now the first effects of the European mad cow epidemic are being felt by U.S. consumers. Although no cases of mad cow disease have been identified in this country, Americans planning European vacations are worried about eating in restaurants there.

In animals infected with bovine spongiform encephalopathy (BSE), the scientific name for mad cow, the abnormal proteins that typify the disease have been found in the brain and spinal cord, the nerve tissue near the backbone, the retina and the bone marrow.

Cuts of beef considered most likely to contain contaminated material are brains, hamburger, beef sausages and T-bone steaks. At one time, all bone-in cuts of beef were banned in Great Britain.

Travelers to Europe this summer are not likely to find beef brains on restaurant menus. Bone-in steaks, such as the famous Tuscan T-bone, will not be available, either.

Although other cuts of beef can be found on many European restaurant menus, seafood and vegetarian items are increasing in popularity -- and price ...

Travelers who are worried about the disease may wish to either avoid beef or order only solid-muscle cuts, such as roasts and boneless steaks ...

Leather prices are rising worldwide because of mad cow. Fewer cows are being slaughtered in Europe, which has resulted in fewer cowhides, a byproduct of the meat industry.

The wholesale price of leather hides increased 20 percent this spring, reaching historic highs, say furniture makers. Although the increases have not been passed on to retail customers yet, higher prices may be ahead for products ranging in size from wallets to sofas.

Jane Snow is the Beacon Journal's food writer. She can be reached at jsnow@thebeaconjournal.com.

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ARTICLE from THE AKRON BEACON JOURNAL, 6-3-01, BY TRACY WHEELER, Beacon Journal medical writer

``Beef may not be only danger

U.S. blood suppliers weigh tougher ban on donors seen as mad cow risk, amid blood shortage

Among Paula Grau's bills and junk mail was a letter from the hospital. It told her that her son might have contracted an incurable, deadly disease six years earlier when he was given a blood transfusion shortly after birth.

Grau was stunned.

``I didn't understand it,'' said Grau, who lives in Ontario, Canada. ``I fell apart, thinking my wonderful, uplifting, precious son would die . . . not understanding that this was a hypothetical or theoretical situation. I was just reading that he got blood from someone who died from a disease that is fatal.''

The disease the donor had was Creutzfeldt-Jakob (CJD), and the letter told her there was little reason to be concerned, that there was ``virtually no evidence'' that her son would develop it.

But for five years, since she received the letter, Grau has worried, even though she knows that the risk to her son Jordan, who's now 11, is minuscule.

There is not a single known case of CJD -- which can incubate in the body for decades -- being transmitted through blood. But Grau's story illustrates why the two main blood suppliers in the United States -- the American Red Cross and America's Blood Centers -- are debating about the right way to safeguard the nation's blood supply from CJD and its mad cow-linked variant (vCJD).

America's Blood Centers is following the recommendations of the Food and Drug Administration.

Under these guidelines, anyone who lived or traveled in Great Britain for a total of six months or longer between 1980 and 1996 should not donate blood. The same applies for those who have lived or traveled in France or Portugal for a total of at least 10 years since 1980.

The American Red Cross is also following the FDA guidelines for now, but is expected to put much stricter ones in place by September.

These stricter guidelines would turn away donors who have been in Britain for a total of only three months or longer since 1980 and those who have spent as little time as six months in Europe since 1980.

``The American Red Cross plans to implement this policy because it's a prudent and cautious (decision) to prevent the spread of CJD,'' said Jill Garman Neiger, spokeswoman for the Red Cross' northern Ohio region. ``We are now looking . . . to be the most cautious we can be.''

In the view of some people, however, that's too cautious.

Blood is already in short supply, and such strict policies will only worsen the shortage, said Melissa McMillian, spokeswoman for America's Blood Centers.

The Red Cross expects to lose 6 percent of its blood supply under the stricter policy. That translates into about 360,000 donors nationwide -- and 12,000 people in Northeast Ohio -- being turned away.

It sets up the very real possibility that more people could die from a lack of blood than from vCJD -- a disease that has yet to appear in the United States.

``It's important to look at the risk vs. the needs,'' said Dr. Scott C. Ratzan, editor of the Journal of Health Communication. ``With this, it's such an infinitesimal risk, but you can actually hurt the blood supply. What happens when something else comes down the pike, a legitimate threat, and the supply suffers again?

``The Red Cross may have jumped a little too quickly, without looking at the scientific debate.''

Even experts can't agree on whether CJD can be passed on in a blood transfusion. When deciding on its guidelines, the FDA advisory committee's votes were often 8-to-7.

``I don't think it's a real risk,'' Ratzan said. ``The scientists on the panel could have easily gone the other way.''

But the Red Cross is remembering what happened in the 1980s, Neiger said, when scientists didn't know whether the AIDS virus could be spread through blood.

By the time the scientific community determined that it could, many people had already been infected by HIV through blood products.

Better safe than sorry

Dr. Jeffery Hord, the director of hematology/oncology at Children's Hospital Medical Center of Akron, sides with caution.

``I think that it is appropriate to put in as many safety checks as possible,'' he said. ``Certainly after the unfortunate transmission of HIV and hepatitis through the blood supply in the early '80s, it led everyone to be more cautious. One can't be faulted for doing that.''

A wide range of patients, including hemophiliacs, cancer sufferers and accident victims, need blood products.

``Those in the general population, who may need one transfusion in a lifetime -- they may be willing to accept this remote risk in order to have blood available,'' Hord said. ``However, if you're a patient with hemophilia and you get treatment twice a week -- factor concentrates can include (blood from) 2,000 to 3,000 donors -- you are exposed to thousands and thousands of donors. The risk is suddenly very different for that patient.'' ...

``I believe, and it's the Red Cross' position, that the blood supply is the safest it's ever been,'' Neiger said. ``The reason it's so safe is because the Red Cross takes caution when it can and when it should.'' ''

Tracy Wheeler can be reached at tawheeler@thebeaconjournal.com

SUMMARY:

Transmissible spongiform encephalopathies are a family of degenerative neurological diseases characterized by brain deterioration, beginning with loss of vision and quickly progressing to loss of balance and body control, dementia and death.

No cure or treatment exists for humans or animals.

Among these disorders are:

Scrapie -- Affects the nervous system of sheep. First recognized in Europe more than 250 years ago. Causes weight loss, changes in temperament, gait abnormalities and eventual collapse.

Chronic wasting disease -- Affects deer and elk in six Western states and Canada. Has been shown to infect human cells in laboratory experiments.

Bovine spongiform encephalopathy -- Commonly called mad cow disease. First identified in cattle in England in 1986. Primary means of transmission to animals thought to be feed tainted with protein supplements made from infected animals.

Creutzfeldt-Jakob Disease -- Affects men and women, typically between the ages of 50 and 75, after decades of lying dormant in the body. Accounts for one to two deaths per million each year, though that number is suspected to be somewhat higher due to misdiagnoses. In most cases, the cause is unknown; about 10 percent to 15 percent of the cases have a genetic origin and about 1 percent are contracted through medical procedures. Once symptoms appear, death occurs within three to six months.

Variant Creutzfeldt-Jakob Disease -- Suspected to be caused by eating meat from cattle infected with mad cow disease. Symptoms are similar to CJD, although the disease lasts up to 13 months and usually strikes victims at a younger age. Incubation period is 10 to 20 years.

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ARTICLE from THE AKRON BEACON JOURNAL, 6-4-01, BY MARY ETHRIDGE, Beacon Journal business writer

``Renderers say government regulations are ruining business ...

Four years ago, Garry Baas gladly paid for the privilege of picking up other people's dead animals.

These days, he won't be bothered. There's no money in it anymore, thanks to government regulations designed to prevent the spread of mad cow disease in the United States ...

Baas knows of only one person in Ohio now willing to pick up dead animals from farms, homes and pet shelters. And that makes him wonder.

``We (Ohio renderers) picked up 13 million pounds of dead animals a year,'' he said. ``So what's everyone doing with them now? ..."

Rendering is at the vortex of the debate on mad cow -- a fatal neurological disease that affects cattle and is believed to spread the equally deadly variant Creutzfeldt-Jacob Disease to people who eat beef.

The industry is one most people would prefer not to think about. It has long been a staple of agricultural towns across America where it was often called simply ``the glue factory'' or ``the dog food plant.''

Renderers collect meat scraps, grease and dead animals, including cows, pigs, dogs, cats and roadkill, and then cook them to extract the most useful ingredients. Those ingredients are put into everyday products such as cosmetics, lubricants, pet food and livestock feed. Traditionally, it has been a lucrative business, worth about $2.5 billion in sales nationwide last year ...

Rendering plants, scientists generally agree, is where mad cow first took hold and incubated in Great Britain in the early 1980s. In 1997, the Food and Drug Administration took particular aim at U.S. renderers -- and the feed manufacturers they serve -- with regulations designed to prevent the spread of mad cow in this country.

During rendering, animal carcasses are ground up and then decomposed in large vats by boiling under extremely high pressure. The process produces a slurry of protein under a layer of fat called tallow. That slurry is dried into a meat and bone meal product.

The FDA regulations banned adding meat and bone meal made from ruminants -- animals with four stomachs, such as cows and sheep -- to feed for ruminants.

The ban hit renderers hard. About 80 percent of U.S. sales of rendered products are to feed manufacturers, according to the National Renderers Association ...

Dean Slates, agricultural extension agent for Holmes County, agrees that renderers' recent unwillingness to pick up dead animals has caused significant disposal problems.

But he doesn't think most people will resort to tossing carcasses into a ravine or dragging them into the woods. For one thing, the state and federal governments -- well aware of the high disease potential -- has set up hefty penalties for doing so ...

``I'd be less than honest if I said no one would do that,'' Slates said. ``But I don't think it would ever become widespread.''

Outside of rendering, there are few, if any, particularly appealing choices for disposing of dead animals in Ohio.

Ohio Environmental Protection Agency regulations permit farm animals -- though not roadkill -- to be buried. But it's hard to dig a big enough hole in frozen winter ground, and water and space conditions must be just right to meet EPA regulations.

Incineration is a neat solution, but the equipment and fuel are expensive.

Landfills willing to take dead animals are widely scattered and shrinking in number.

The only other option is composting, a decade-old practice in the poultry business but one rarely used outside it ...

A case in point comes from the Ohio Department of Transportation. In 1999, ODOT began dumping dead deer on a median strip of Interstate 271 in Medina County, not far from Highland High School.

Until then, the department had been tossing the deer into a trash bin from which they would be hauled to the only nearby landfill willing to take them, said Bill Leitch, Wayne County manager for ODOT.

When the landfill stopped taking the deer in 1999, Leitch tried unsuccessfully to find a renderer that would handle them. ODOT was not allowed to bury the deer because of the EPA prohibition on roadkill burial. Incineration would have been too difficult and expensive. No other landfills would take the deer.

So last year [2000] ... a deer-composting facility was created in Wayne County, on the eastern outskirts of Wooster. It was the state's first EPA-licensed composting facility for roadkill.

Eventually, the composted remains are expected to become fill dirt for state road projects.

Angela Evans of the Ohio EPA's division of solid and infectious waste management said the agency supports composting. Although burying dead farm animals is allowed with restrictions, it's not encouraged because of its potential to pollute groundwater.

But, she said, composting of large animals has been slow to catch on because it's new to most people and requires significant space, special training and a license ...

Though no cases of mad cow have been found in the United States, there's no way to be certain that the disease isn't here incubating. Symptoms of mad cow do not appear for two to eight years, and cattle can be tested for the disease only after they're dead.

Paul Brown, senior researcher at the National Institutes of Health, said that if by some chance mad cow were incubating here -- and he stresses that there's no hard evidence it is -- then animal carcasses that have been buried, composted or even incinerated in the usual way would indeed pose an environmental threat.

That's because mad cow is caused not by a virus or bacteria, but by an abnormal protein called a prion, which is hardy enough to survive long periods and doses of high heat and chemicals.

``It's a very durable pathogen,'' Brown said.

To find out just how durable, Brown and a colleague took several cow brains infected with bovine spongiform encephalopathy -- the scientific name for mad cow disease -- and buried them in a field. Three years later, the brains had decayed, but the ground where they had been buried was contaminated with prions ...

If animals grazed on ground contaminated by prions, they would likely become infected. Scientists believe grazing in prion-contaminated fields is one of the primary ways that scrapie, another prion disease, spreads in sheep. It's a likely reason that chronic wasting disease, which is also caused by prions, is spreading among deer and elk herds in six Western states.

``It's theoretical,'' Brown said, ``but, yes, the practice (burying cattle infected with mad cow) would create problems.'' ... ''

Mary Ethridge can be reached at methridge@thebeaconjournal.com

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ARTICLE from THE AKRON BEACON JOURNAL, 6-4-01, BY MARY ETHRIDGE, Beacon Journal staff writer

``Livestock industry turns cattle into cannibals ...

In one sense, it was oil that turned cows into cannibals.

During the 1950s and 1960s, soap manufacturers switched from using tallow in their products to petroleum-based synthetics.

Tallow is a product of the rendering process in which animal carcasses are ground up and decomposed in large vats by boiling under extremely high pressure. Anxious to replace this lost tallow business, renderers courted livestock feed manufacturers with their other product -- dried meat and bone meal ...

In 1980, worker safety issues led renderers to eliminate the use of hydrocarbon solvents in extracting fat from the slurry that is dried into the meat and bone meal. Renderers also installed new continuous cookers that processed the material at lower temperatures.

Experts believe the lack of solvents plus the lower temperatures created an environment favorable to prions, the abnormally shaped proteins that ravage the central nervous system in mad cow disease.

The same changes in the rendering process took place in the United States and Great Britain, but scientists believe mad cow disease broke out in England because British renderers used a much higher percentage of sheep to make their products.

For hundreds of years, sheep have carried a prion disease called scrapie, which is harmless to humans. Scientists theorize that scrapie either jumped the species barrier to infect cows, mutated, or acted as a catalyst for the growth of a new prion disease ...

Infected tissue from a single animal [could be] mixed with tissues of thousands of others. Sophisticated marketing distributed the products and the infection to a wide geographic area.

Cattle ate the prion-contaminated feed, became infected and were eventually rendered into a contaminated product added to more feed ... ''

Mary Ethridge can be reached at methridge@thebeaconjournal.com

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ARTICLE from THE AKRON BEACON JOURNAL, 6-5-01, BY TRACY WHEELER, Beacon Journal medical writer

``Scientists search for way to detect mad cow

CLEVELAND: On the ninth floor of Case Western Reserve University's biomedical research building, Man-Sun Sy's lab looks like any other.

With diligent precision, a young researcher squirts a bluish gel from a syringelike device into a small water-filled container. A piece of paper, about the size of a Post-It note, swishes back and forth in a petri dish next to him.

If Sy and his team of researchers find what they're looking for, a dark band will appear on the paper. And with each dark band they discover, they inch closer to providing some answers to dealing with bovine spongiform encephalopathy -- mad cow disease.

The hope is to develop a blood test that could detect mad cow or its human cousin, Creutzfeldt-Jakob, before the diseases bore irreversible, microscopic holes in the brain.

Their task is not an easy one, though.

For starters, the elements that cause the diseases -- renegade proteins known as prions -- have never been found in blood. Scientists don't even know if prions can exist there.

Still, Sy, a Case Western pathology professor, takes an optimistic view.

``Just because we can't find it, doesn't mean it isn't there,'' he said. ``If it is there, we'll find it.''

A lot of people are hoping so.

Mad cow and Creutzfeldt-Jakob now can only be diagnosed after death, through microscopic inspection of brain tissue.

With a blood test, a farmer could learn if a cow is infected before the meat goes to market.

With a blood test, a blood supply could be checked for infection before a transfusion.

With a blood test, the disease could be detected early, while it is still in its long incubation period, before the brain destruction begins.

And that, ultimately, could lead to a treatment or cure.

``If there was a test like that,'' said Case Western neuropathology professor Robert B. Petersen, ``all of a sudden there would be an incentive for the big pharmaceutical companies to develop a therapeutic because they now have a market.'' ...

The fact that prions have been found in the appendix, the lymph nodes and tonsils leads researchers to believe prions can be found in the blood, too.

But as Petersen pointed out, prions could be more like the bacteria that cause tuberculosis -- present in tissue, but not in blood ...

A blood test offers the most promise to the most people. Unlike a radiographic brain scan, it could detect the disease early. Unlike a lymphatic tissue test, it could be repeated regularly without incisions or risk of infection.

The body's immune system is what makes it difficult for researchers to develop a blood test for prions.

Normally, when foreign invaders, such as HIV or streptococcus bacteria, attack the body, the immune system springs into action, setting loose an army of antibodies to fight the intruder.

Those antibodies in the blood are like footprints in the sand -- clear proof of what was there before.

Unlike a virus or bacterium, prions don't trip the immune system's alarms. No antibodies are deployed; no footprints are left behind.

Prions go unnoticed, undetected and unabated.

The reason? Prions have a nearly identical chemical makeup to good protein in the body. The only difference is in the shape, the outward appearance.

``Just like you and I have the same exact genetic material but we have on different clothes,'' Sy explained.

It's the abnormal shape that makes prions harmful. The shape allows the prion to latch onto healthy proteins one at a time, turning good proteins bad and slowly creating a colony of destructive prions.

Since researchers can't use the immune system to detect intruding prions, they must come up with another way to find them.

Sy and his Case Western colleagues have managed to do that in mice by creating a strain of rodents in which a specific protein -- known as a prion protein -- is deleted from the genetic code. When these mice are infected with prions, Sy said, ``they recognize it as foreign and create antibodies like crazy.''

The hope is that these mouse antibodies can be used to detect prions in the blood of humans and other mammals that carry prion diseases.

So far, by adding the mouse antibodies to brain tissue, the Case Western researchers have been able to locate specific proteins that most closely resemble prions.

That's not the same as finding the infectious prions, though. It will take more research -- at least a year's worth -- to move from finding proteins in brain tissue to the ultimate goal of finding prions in blood.

Researchers don't know whether any blood test will be able to detect classic Creutzfeldt-Jakob, or whether it will only be able to detect variant Creutzfeldt-Jakob, the version of the disease contracted by eating mad cow-tainted beef.

Dr. Pierluigi Gambetti, director of the National Prion Disease Pathology Surveillance Center housed at Case Western, expects that it will be easier to test for mad cow and variant Creutzfeldt-Jakob because in these diseases, ``the bad prion goes from the gut to the brain,'' meaning it has to enter the bloodstream to get there. Classic forms of the disease start in the brain.

It's also unclear how accurate a blood test could be. Prion diseases can incubate in the body for decades.

``The question that comes up, then, is whether there are prions circulating on a daily basis,'' Petersen said. ``The answer is, no one really knows.''

In other words, a negative test result might mean a clean bill of health. But it also might mean the prions are simply dormant, waiting to strike a decade or two from now ... ''

Tracy Wheeler can be reached at tawheeler@thebeaconjournal.com

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ARTICLE from THE AKRON BEACON JOURNAL, 6-5-01, BY TRACY WHEELER Beacon Journal medical writer

``CJD gaining attention in United States

In the middle of August, June Burdick simply stopped feeling well.

By Labor Day, her walk had taken on a noticeable wobble. And she was talking nonstop -- something out of character for this reserved 73-year-old resident of rural Nebraska.

Within days, her speech became slurred, her walk grew clumsier and her left arm turned uncontrollable, flinging itself into the air as if shooing away flies.

The CAT scans, bone scans, MRIs, vital signs and spinal taps showed nothing unusual.

By mid-September, doctors diagnosed Burdick as having a stroke, ``simply because they couldn't find anything else wrong with her,'' said her daughter, Marianne Fisher.

``They did a test for everything they could think of, then redid them again. The doctors were as frustrated as we were. They were running out of tests to do. They even tested her for Lyme disease.''

Burdick's behavior grew increasingly bizarre over the next two weeks. She laughed at everything, as if drunk. She sat in her bed, pretending to conduct an orchestra. She feared the dark, along with the colors blue and green.

By Oct. 8 -- less than six weeks after the symptoms began to show -- Burdick was dead. It wasn't until four days before her death, after a four-hour trip to see a doctor in Fort Collins, Colo., that her family finally began to learn what was wrong.

``The doctor walked in . . . and within five minutes, we had a probable diagnosis of CJD,'' Fisher recalled. ``Of course, we'd never heard of it.''

Many people are unfamiliar with Creutzfeldt-Jakob disease -- CJD for short. But it's gaining attention in the United States as a new version -- variant Creutzfeldt-Jakob (vCJD) -- spreads through Europe, leaving a rising death toll in its wake.

This variant was discovered in Great Britain in 1996. Scientists concluded it was caused by the consumption of beef tainted by mad cow disease.

Both mad cow and Creutzfeldt-Jakob are part of a family of neurological diseases called transmissible spongiform encephalopathy. Scrapie in sheep and chronic wasting disease in deer and elk also are part of this disease family.

Scrapie has never passed CJD to humans, but three CJD deaths -- two hunters and a person who ate venison -- have been linked to infected deer and elk in Colorado, Wyoming, Nebraska, Montana, South Dakota and Oklahoma.

In all these diseases, abnormally shaped proteins called prions ravage the central nervous system. Prions are virtually indestructible and invisible to the body's immune system.

In some cases, prions are believed to enter the body through tainted meat or surgical equipment, slowly latching onto and altering healthy proteins. In other cases, prions form on their own.

``Through the course of your lifetime, you make bad proteins and your cells know how to degrade them,'' said Robert B. Petersen, an associate professor of neuropathology at Case Western Reserve University.

``They identify them, shunt them off, degrade them, and start over without (allowing) any type of pathological process. When you age, apparently these mechanisms that do the surveillance -- the cellular cops -- break down. They're just not as efficient.''

When that system fails and prions thrive, disaster follows. Though the prions can be dormant for decades, they will eventually gnaw away at the nervous system, drilling microscopic holes throughout the brain.

The first sign of both CJD and vCJD is blurred vision or a loud ringing in the ears, followed by a loss of balance, arm and hand tremors and dementia. Death is a certainty.

The classic form of Creutzfeldt-Jakob typically strikes between the ages of 50 and 75, after decades of lying dormant in the body. In 85 percent of the cases, the cause is unknown. About 10 percent to 15 percent of the cases have a genetic origin and about 1 percent are contracted through medical procedures.

Death occurs quickly once symptoms appear, often within three to six months.

The victims of vCJD are much younger, with 28 being the average age of onset. And the symptoms, while similar, last longer, up to 13 months until death.

``It's just such a horrendous thing to see somebody's mind go so fast,'' Fisher said of her mother. ``Thank God she didn't linger.''

If variant Creutzfeldt-Jakob ever reaches the United States, Dr. Pierluigi Gambetti will be one of the first to know.

Gambetti is director of the National Prion Disease Pathology Surveillance Center, housed at Case Western Reserve University. The center tracks and investigates suspected cases of CJD and vCJD in the United States.

Since the center opened in 1997, 480 cases have been investigated, with 294 diagnosed as CJD. None was identified as vCJD.

However, Gambetti said not every suspected case of CJD or vCJD makes its way to the center. In some cases, the doctors simply don't recognize the symptoms and misdiagnose the death as a stroke or Alzheimer's.

In others, doctors suspect CJD, but the family refuses to permit an autopsy for personal, religious or financial reasons.

And in still other cases, pathologists are too scared to perform autopsies, fearing exposure to the deadly prions.

It's estimated that CJD is the cause of one to two deaths out of a million. Based on a U.S. population of 284 million, Gambetti expects to find a little more than 400 cases of CJD each year. Instead, he saw only 111 in 2000, about a fourth of what was expected.

``The chance of losing an important case is high,'' he said. ``I won't be completely happy until we reach 80 percent, at least.''

Two studies have found that doctors often don't recognize CJD. One by Yale University found that 13 percent of suspected Alzheimer's patients had actually died of CJD. Another at the University of Pittsburgh showed that 5 percent of Alzheimer's patients were CJD victims ...

Those who have heard of [mad cow disease] are often confused by a diagnosis of CJD, thinking that it means a loved one has mad cow disease. For a death to be linked to mad cow, however, an autopsy would have to find vCJD.

Epidemiologists can quickly tell the difference between the two.

Under a microscope, classic CJD would show up in brain tissue as tiny holes. In vCJD, the holes would be surrounded by blotchy white patches of protein referred to as plaques.

If such a sample were to arrive at Case Western Reserve University, ``it would jump out at me,'' Gambetti said.

Sandy Allen, who lives on a small farm in Midland, Texas, isn't reassured that scientists have not found a case of vCJD in the United States.

She believes that both vCJD and mad cow are already here -- and that the government is covering it up.

``I don't know if the government will ever fess up to it,'' she said. ``I like to say, `They'll do it when the mad cows come home.' ''

Her concern about mad cow disease is understandable. Her mother died of CJD 11 years ago, and every time she hears a ringing in her ear or stumbles over her feet, she worries that she has been stricken, too.

``Oh, I think about it all the time,'' she said. ``I'm not worried about cancer. I'm not worried about heart disease. I'm deathly worried about CJD. I'll do myself in. I'm not going to go through that.

``How do I know I didn't eat what my mother ate? You don't know what's in sausage anymore. You don't know what parts of the animal are used for what.''

On the other hand, Fisher doesn't think it really matters whether vCJD is in the United States. CJD is here, killing people.

``When you say there's no (mad cow) in the United States,'' Fisher said, ``I don't think people understand that's not the same as saying there's no CJD in the United States.'' ''

Tracy Wheeler can be reached at tawheeler@thebeaconjournal.com

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