Can Mad Cow Disease Reach Our Shores?

In the first report of a three-part series, CBS News correspondent Wyatt Andrews describes efforts to build a US firewall against mad cow disease. The hope is that this country can learn from Europe's mistakes. The sickness has killed more than 80 people, mostly in Britain--a few in France, Ireland, and elsewhere in Europe. Additionally, more than 180,000 animals in Britain have been reported to be infected.

Four years ago in England, Pamela Beyless wore the blank human face of mad cow disease. Her father, Arthur, recalls her regression from confusion, to loss of balance, to total disability.

"She couldn't blink her own eyes," he says.

At the time, the British government played down the mad cow scare, assuring the public that the beef was safe. That's why Arthur Beyless couldn't connect stumbling cows to the brain-eating disease afflicting his daughter.

"Pamela was still Pamela inside, just locked in a body that was destroying her," recalls her father.

Scientists say they think the human form of mad cow disease is contracted by eating tainted beef, and cows get it by eating feed containing the remains of infected cattle.

Tainted feed was exported from Great Britain to Western Europe, where the disease spread.

Today in the United States, it is Linda Detwiler's job to keep the beef safe, and she says she is certain she can do it. She's the chief of the US Department of Agriculture (USDA) task force watching out for mad cow disease, which means she's watching 40 million head of cattle.

Under the US system, any cow showing signs of brain disease gets reported; most get destroyed and their brains are sent to the USDA lab. They've checked 12,000 brains. So far there have been no signs of mad cow disease.

"We have done over a decade of preventive activities, a decade of surveillance with no evidence of the disease, " boasts Detwiler.

Leon Smith, MD is an infectious disease specialist and chief of medicine at St. Michael's Center in Newark, New Jersey. He's more worried about humans than cows. "I think it will be an absolute miracle if we don't have any cases in this country," he says.

Smith points out that science doesn't know exactly what part of the cow harbors mad cow disease--and his concerns are not just for edible beef: English beef by-products like cosmetics and vaccines could be dangerous, too, he says. "Theoretically it can be in gelatin, bovine serum, and other products."

Smith says scientists haven't been able to rule out such possibilities because there is no way to test for them.

Despite the effort to erect a US barrier to mad cow disease, there are holes in the wall, and one of them is cattle feed. Here's why: To protect US cattle from eating tainted feed there is supposed to be a label warning farmers when feed contains by-products of animals susceptible to mad cow disease.

That system is broken.

Just last week, 12,000 cattle were isolated in Texas when Purina annonced it had mistakenly put cow remains in a batch of cattle feed. The Food and Drug Administration (FDA) recently reported that more than 700 feed makers were not labeling products as required.

Stephen Sundlof, DVM, MD, of the FDA is asked if that level of compliance was acceptable to him. "No, it's not," he replies

Sundlof, who is the official in charge of protecting feed, says all 700 feed makers are being reinspected, and there have been five recalls of cattle feed. He says, "We can't say for certain that some of this has not been fed to other cattle. That concerns us."

As of today, the infectious agent that actually causes mad cow disease has never been found in US cows or US humans. The beef is safe, the risk of infection small, experts say. But be vigilant, says Arthur Beyless back in England. He's heard most of that before.

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