Mad cow danger may even be bigger

Below the drumbeat of reassurances from government and the cattle industry that the meat supply remains safe despite this one case of mad cow disease, a small universe of scientists working on a family of related illnesses is finding disturbing evidence to the contrary.

Several studies, including research at a government laboratory in Montana, continue to spark questions about human susceptibility not only to mad cow, but also to sister diseases such as chronic wasting disease, which mainly affects deer and elk, and scrapie, which infects sheep.

Mice research and clusters of cases in which humans contracted a disease similar to mad cow also has a few scientists wondering whether consuming infected meat might have killed far more people than medical experts have long assumed, not only in Great Britain, but in the United States as well.

Most scientists believe the relatively small number of known human cases, called Creutzfeldt-Jacob disease, strongly indicates this disease -- whatever its cause or origin -- is rare and difficult to transmit. There is also no evidence yet that scrapie in sheep or chronic wasting disease in deer has ever been passed to humans.

But some scientists say it's possible that chronic wasting, endemic in Colorado's wild deer and elk, has sickened and proved fatal to humans. These experts challenging the standard view note that doctors haven't -- or can't -- recognize signs of these other forms of the disease during an autopsy.

Little of this research reaches the broad public audience, leaving most people to hear only the oft-repeated promises of well-funded interest groups or high-profile public officials.

Just last week, for example, the National Cattlemen's Beef Association described mad cow disease solely as an animal and economic problem -- not a human health problem. The U.S. Department of Agriculture has said repeatedly that the nation's beef supply is safe.

Such statements, offered frequently since the December discovery of a Holstein with mad cow disease in Washington state, spark criticism from some scientists and consumer advocates who say that the government and industry are injecting certainty into a field where uncertainty remains the dominant theme.

Much remains unknown about so-called transmissible spongiform encephalopathies, or TSEs, the family of diseases to which mad cow, scrapie, chronic wasting disease and two human versions -- known as Creutzfeldt-Jakob, or CJD, and "new variant" CJD -- belong.

This rogues' gallery of deadly illnesses features an array of frightening symptoms. In humans they can include depression, inability to conduct simple tasks such as operating a telephone and loss of balance and speech. In every case, the victim's brain becomes riddled with holes; thoughts, emotions and memories disappear on the way to death, often in just a matter of months.

It's long been believed, for example, that only one of the two versions of human CJD can be linked to eating meat contaminated with mad cow disease. The other version, known as sporadic or classical CJD, has long been thought to occur randomly in about one in every million people, a distinctive illness with no link to meat from an infected animal.

But a few studies in the past three years have challenged that view, suggesting that classical CJD, might, in some cases, also result from eating contaminated meat.

Scientists in Great Britain injected tissue from a cow with mad cow disease, also known as bovine spongiform encephalapothy, into mice whose brains were genetically engineered with human genes. One set of mice fell sick with the human form of mad cow, or new variant CJD.

But, in a finding that stunned researchers worldwide, another set of the genetically altered mice developed what looked like the sporadic form of CJD, the one scientists have long believed has no relationship to mad cow disease or meat-eating.

"This finding has important potential implications as it raises the possibility that some humans infected with (mad cow disease) may develop a clinical disease indistinguishable from classical CJD," the researchers wrote in November 2002.

French scientists a year earlier found a strain of scrapie, the version of the disease that infects sheep, also caused brain damage in mice similar to classical CJD.

Though these findings run counter to most studies, the two studies suggest that some of the hundreds of Americans who contract classical CJD each year could have been infected by mad cow-contaminated meat, and not simply by biological bad luck.

Then there are the mysterious clusters of human cases. Because classical CJD is so rare, scientists don't usually expect it to occur in clusters. But such clusters have occurred, including among hunters eating venison.

The most recent example involves seven people who apparently died of classical CJD in New Jersey. All of them had a link with a racetrack in Cherry Hill where they ate, according to reporting this month in The Philadelphia Inquirer.

Most surprising: The deaths included a 29-year-old. It's extraordinarily rare for someone so young to die of classical CJD. Victims are typically older than 55. In contrast, victims of new variant CJD in the 1990s mad cow panic in England were often young people.

The U.S. Centers for Disease Control and Prevention wasn't initially interested in the cluster, but since the discovery of the case of mad cow in Washington state the agency is taking another look at the case, according to The Inquirer.

Even so, experts caution that clusters can also be coincidences. Rare diseases don't always end up geographically spread out.

"The cluster is curious, but these sorts of things can happen by random chance," said Patrick Bosque, a neurologist at Denver Health and an expert on TSE.

Bosque is open-minded about the possibility of humans contracting such diseases at a higher rate than is currently believed, but is also cautious about jumping to conclusions.

"With almost 300 cases of CJD expected in the U.S. each year, it isn't too surprising that over a few years one might occasionally find a cluster associated with some ill-defined event or place," he said.

But some scientists believe the true number of U.S. CJD cases is underreported, and the disease is not as rare as once believed. Some experts believe that it is possible that some cases diagnosed as Alzheimer's could actually be CJD. Some other dementia-like diseases could also be misdiagnosed, experts say.

"Given the new research showing that infected beef may be responsible for some (classical) CJD, thousands of Americans may already be dying because of mad cow disease every year," wrote Dr. Michael Greger, a physician and vegan advocate.

Many scientists, however, caution that if mad cow disease were really fueling an increase of classical CJD in the United States, then we should also be seeing many more cases of new variant CJD, the form of mad cow disease that struck people in Great Britain.

Even in Britain, where millions of people were estimated to have eaten mad cow-contaminated meat, fewer than 150 people came down with new variant CJD.

"Could BSE have been transmitted to people in the U.S. but gone unrecognized because it looked like (classical) CJD?" Bosque said. "I suppose it is possible, but there would be no obvious explanation for the fact that (new variant) CJD has not been seen in the U.S."

But the critics answer that the United States has no formal monitoring system in place to track CJD cases and autopsy the victims. That would enable scientists to more accurately detect trends in occurrences and study the pattern of destruction in the brain that reveals whether a victim died of classical or new variant CJD.

At a National Institutes of Health laboratory in western Montana, researchers are focused on the question of what happens when TSEs move back and forth between different animals. What they've found is unsettling.

Their latest research is an extension of work they've been conducting for several years. It shows that TSEs can be passed to some animals without causing disease, but then passed onto another species where they cause illness.

Researchers began by taking brains of hamsters infected with scrapie and injecting that tissue into mice. Then, they killed the mice at various points and tested for presence of the infectious agents -- called prions -- in the brains of mice. They didn't find any.

But researchers took the next step, injecting tissues from these apparently prion-free mice into another set of healthy mice and hamsters. That's when the outcome turned frightening: the newly infected creatures developed TSEs and died.

What does it mean? The mice from the earlier part of the experiment were not free of the disease after all. They were silent carriers of a sort, not showing any signs of the illness but able to infect others.

This could have dramatic implications for the real world. What if, for example, some humans carry mad cow disease or another TSE, but aren't affected by it? Perhaps they could still pass it on through blood transfusions or transplants. In the words of researchers: "Subclinical human carriers might pose a serious risk for contamination of surgical instruments, tissue transplants and blood products," according to a 2002 report on the mice-hamster experiments in Montana.

Michael Hansen, a scientist for Consumers Union, points out that cattle tissues that are mostly removed from the human food chain are still converted to feed for chickens and pigs, among others.

Remains of those animals, in turn, are still rendered into cattle feed -- a practice derided by critics and banned in Europe, but still legal and common in the United States.

The Montana researchers have continued their work, injecting tissues from the mice and hamsters that became sick into yet another set. The next generation of mice and hamsters got sick as well.

The infectious prions appear to persist and adapt, evolving to infect a new species and even becoming more virulent as they move between species. In some cases, incubation periods change, growing longer or shorter depending on the experiment.

In short, behavior of the diseases has been unpredictable, making statements of certainty about them untenable.

Bosque, the Denver neurologist, said the ability for TSEs to hide inside some animals and increase their infectivity is worrisome.

"It raises an additional level of concern, that these prions can persist in animals, and increase, even though (the animals) don't appear sick," Bosque said. "For one thing, it shows you that screening for just obviously sick animals may not be sufficient."

But currently, the United States focuses its testing almost solely on sick or "downer" animals. Industry officials have said testing every cow for mad cow disease as Japan does would be a waste of time and money.

* Mad cow disease: Also known as bovine spongiform encephalopathy, this disease infects cattle. Infectious proteins called prions kill brain cells, causing spongelike holes to develop. First identified in Europe in the 1980s.

* Chronic wasting disease: This illness infects deer and elk. No cases of transmission to hunters eating the meat have been confirmed.

I have a friend whose mother died of CJD some years ago. He will never be allowed to donate blood because the authorities are uncertain about how it is transmitted. Potentially pretty scary stuff. We are still eating beef, but we've decided to only buy hamburger from a butcher we know and trust.

Then I got me knighthood and he stopped returning my calls.

Since you travel in those circles, perhaps you'd know this.

Is Ozzy much of a meat eater?

Maybe it wasn't the drugs after all.

The danger of e. coli contamination is far greater than the possibility that a few stray prions, a form of twisted protein, get into the food chain. Let us look at this logically. Most beef consumed is cooked, which tends to denature protein molecules. Further, when proteins pass through the human digestive system, they are broken down into the constituent amino acids, and do not enter the blood stream as a whole protein, no matter how twisted. Lastly, there is a barrier between the blood and the neurologic tissue, brain and nerve fibers, that filters out any unrecognized organic substances, which is a major factor in homeostatic health.

There may be an unrecognized agent that causes the proteins to twist into the prions which are characteristic of CJD and BSE. We have not yet discovered it. It may be a virus, or some bacterium that is normally considered to be benign, and is only activated under certain combinations of circumstances not yet identified. Or it may be a genetic disorder within certain genotypes that only appears when certain environmental factors are present.

My thoughts? Time to become a vegetarian..

Worst thing you could ever do to yourself.

As far as Mad Cow, you have a greater chance of being hit by an asteroid than contracting the malaise. In a nutshell there is no proof of any kind that you can get MC by eating meat, only Brains & Spinal Cord matter. Even then it is virtually impossible. In closing, enjoy that steak and do not become a veggie. But don't take my word for it, just go to your nearest health food store and look at the people shopping there. 100% chance they will be sickly looking, with pasty spotty skin, unhealthy looking hair & nails. And a veggie will always be sick more that a meat eater. Enjoy!

"Given the new research showing that infected beef may be responsible for some (classical) CJD, thousands of Americans may already be dying because of mad cow disease every year," wrote Dr. Michael Greger, a physician and vegan advocate."

He will never be allowed to donate blood because the authorities are uncertain about how it is transmitted.

I've heard that many Brits are also in that position. And that the blood they use in surgery must be imported.

There's a lot yet to be learned.

The statement from the DOA (Dept of AG, not dead on arrival) employee might be explainable by the fact that: 1) the disease has a decades-long incubation period followed by a rapid decline, dementia and death. Therefore, you might be carrying the disease from a burger you had years ago; 2) classic ovo-lacto vegetarianism includes animal products--vegan excludes all animal products, and 3) animal products are in your shoes, soaps, make up, etc.

A footnote to the above is that there is some speculation that the reason there are so few autopsies of dementia deaths is that the disease is communicable by contact with infected tissue and blood.

Speaking of blood, the DOA has still refused to prohibit the feeding of blood to cattle. And, pork is at risk because pigs are slaughtered at age 2-3 before the disease normally manifests.

I am not telling people to become vegans, but I think everyone should be aware of the threat to our food supply. As the article points out the US has not been keeping track of variant CJD deaths or notifying doctors around the country that many of their dementia patients may actually be CJD.

In the words of Clint, "You gonna finish that burger?"

Most beef consumed is cooked, which tends to denature protein molecules...

Wrong. This is the greatest misconception that people have about mad cow. Cooking will not prevent the disease. Fact of the matter is, whoever decided to feed animal products to cows should be hunted down and shot in the back.

But don't take my word for it, just go to your nearest health food store and look at the people shopping there. 100% chance they will be sickly looking, with pasty spotty skin, unhealthy looking hair & nails.

Could have something to do with 'Mad Bean' diease?

Or it may be a genetic disorder within certain genotypes that only appears when certain environmental factors are present.

I find that possibility interesting. This last weekend another Freeper mentioned that, IIRC, certain beef animals have shown a genetic resistance to BSE, and that microbiologists are now studying this.

We are not giving up eating beef. We are changing some of our buying patterns which I happen to believe is a very smart thing to do for many reasons. Rather than buy meat, particularly hamburger, from multi-national conglomerates, we are buying it from local people who live and work in the community.

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