Brain & Nervous System Health Center

Mad Cow Disease: U.S. Experts Work to Stop It Before It Starts

From the WebMD Archives

Jan. 26, 2001 -- We haven't seen it here yet, but the U.S. is ready for mad cow disease if it should find its way into our cattle supply. The FDA and other health agencies, including the American Red Cross, are watching, waiting, and planning as they work to stave off the epidemic that is spreading across Western Europe.

Even though there has never been a case here, import restrictions on cattle from the U.K. have been in place since 1989, and efforts at active surveillance of our cattle supply started in 1990.

In the most recent development, federal health officials quarantined 1,000 heads of cattle in Texas because a feed mill announced it may have broken the rules governing the preparation of cattle feed. Under these regulations, cows and sheep are not to be fed products containing animal parts, in order to prevent the spread of the disease. But the feed company told the FDA that some of the livestock could have eaten bone meal made from other U.S. cattle. It is just a potential risk, since mad cow disease hasn't been reported in this country, but officials want to investigate.

The FDA has reported that this is not an isolated incident, however, as hundreds of feed makers have been violating the regulations in making their products. Members of the cattle industry will be meeting with the government on Monday Jan. 29, in order to get more businesses to step up their compliance to the rules.

The FDA has also been investigating the risks of contracting the disease in other ways. Researchers are not sure if mad cow disease can be transmitted through blood transfusions, for example. But an advisory committee to the FDA recently recommended widening a ban on blood donations to include long-term residents of France, Ireland, and Portugal to make sure mad cow disease stays out of the U.S. blood supply.

Anyone who lived in any one of these countries for 10 years or more from 1980 on should not be allowed to donate blood for the time being, according to the advisory panel. This committee stopped short of recommending a similar ban for all of Western Europe.


The FDA doesn't have to follow recommendations of its advisory councils, but it usually does. About one year ago, the FDA banned blood donations from any American who spent just six months or more in Britain from 1980 to 1996. Some critics say that restricting who can donate blood may do more harm than good, because our blood supply is already low.

There has also been concern in the U.S. that certain vaccines and/or dietary supplements that use animal protein or glandular extracts, respectively, may be contaminated. The FDA already has issued warnings that supplement makers and pharmaceutical companies should vigorously monitor this to prevent contaminated products from reaching U.S. consumers, but the companies may not be honoring these recommendations or following them as closely as they should. Therefore, the FDA is considering cracking down on regulations that are already in place.

Mad cow disease is the common name for bovine spongiform encephalopathy, also called BSE. It is a degenerative, central nervous system disease that was first diagnosed in cattle in Great Britain in 1986. Affected animals act crazy, or "mad," displaying changes in mood such as nervousness or agitation and having difficulty standing up. Such cattle usually die within two weeks to six months.

Eating infected beef has been linked to a human version of the disease called new variant Creutzfeldt-Jakob disease. This has struck more than 80 people in England and about three people in France.

The disease also has been confirmed in domestic cattle in Belgium, France, Ireland, Liechtenstein, Luxembourg, the Netherlands, Portugal, and Switzerland. Worldwide, there have been more than 178,000 cases since the disease was first found in the U.K.

Ed Curlept, a spokesperson for the Animal and Plant Health Inspection Service, based in Riverdale, Md., is fairly confident that the U.S. has safeguards in place to stop the disease from entering this country's food supply, or to at least find it before it becomes widespread.

"This has been on the top of our priority list for 10 years," he says. "We have looked at over 12,000 animal brains, and we continue to look for BSE in this country by looking at 'downer' cows that can't move."


"We have more than 250 veterinarians that respond to suspicious foreign animal diseases in the U.S.," Curlept tells WebMD. "We are fairly confident, but we are not complacent, and are trying to learn as much as we can from Europeans. If BSE is here, we can either stop it or find it before it becomes widespread."

The Harvard Center for Risk Analysis in Boston had been working under a USDA grant to evaluate the situation in the U.S. should mad cow disease arise here.

George Gray, director of the program in food safety and agriculture there, tells WebMD, "I consider there to be a very small risk to human health or cattle for the U.S. I haven't changed my diet. I still eat beef."

But an ounce of prevention is worth a pound of cure, he says.

Gray credits the safety of the U.S. food supply to the preventive vigilance of the FDA/USDA. "They have taken a lot of action in a situation where we haven't had the disease," he says. "Europe is scrambling to do what we are already doing [after they've already found the disease there]."

For example, the U.S. has instituted the measure that bans the use of animal protein in animal feeds meant for ruminants, or animals that chew cud. "This is a pretty amazing step for a country without the disease to take," says Gray.

There have also been a lot of efforts taken to do determine if the disease is here, he says. "We have been looking pretty hard for seven or eight years and haven't seen it," he says.

But, will mad cow disease ultimately find it's way into the U.S. food supply?

"Never say never," he says. "It's extremely unlikely, [but] that's not to say we won't have a sick cow. We could. In the U.K., they still don't know where it came from, so it is entirely possible that we can have a case."

If this occurs, "U.S. reaction may be out of proportion. The government could do a better job of telling people just how much they are doing," says Gray. "The Germans said 'BSE will never happen here,' and it did; and people went berserk."


The bottom line is that "if we had a sick animal in the U.S., it would not be a good time to be in the hamburger business," says Gray, "[but] whether that's an appropriate response is questionable."

"Panic is a good word for what's going on [because] there has never been a case of [mad cow disease] in this country," says Ruth Kava, RD, PhD, director of nutrition at the American Council on Science and Health in New York City. "It has never been seen here. We don't have it. So I don't see a real reason for widespread fear."

"All that the FDA is doing is just precautionary," she tells WebMD. "There is no evidence that it can be transmitted through blood and no evidence that it can be found in dietary supplements."

The recent FDA actions may be related to mistakes made at the beginning of the AIDS epidemic. "Early on in the epidemic, we thought it could not be transmitted through blood, so donors were not screened," she says.

But "much to our surprise and chagrin, we found that [AIDS] was blood-borne, and that gets our antenna quivering," she says.

There has been concern that dietary supplements may contain imported extracts from brains, testicles, and other organs of cattle -- and whether the cattle were exposed to mad cow disease is unknown.

"People who take dietary supplements with glandular extracts should consider what they are doing," she says. "Some glands, like tonsils, could carry infected material but not necessarily mad cow."