03:06 PM PST on Tuesday, December 23, 2003

Associated Press

Q: What is Mad Cow Disease?

Mad Cow Disease is the layperson's name for Bovine Spongiform Encephalopathy (BSE), a transmissible, slowly progressive, degenerative, fatal disease affecting the central nervous system of adult cattle. There is no evidence to date of BSE affecting U.S. cattle, despite an aggressive surveillance program under which nearly 20,000 animals were tested last year.

Q: Does BSE affect humans?

BSE is a disease that affects cattle. However, there is a disease similar to BSE called variant Creutzfeldt-Jakob Disease (CJD), or vCJD, which is found in humans. There have been a small number of cases of vCJD reported, primarily in the United Kingdom, occurring in people who consumed beef that may have been contaminated. (As of May 2003, there have been a total of approximately 139 cases of vCJD worldwide.)

There is strong scientific evidence that the agent that causes BSE in cattle is the agent that causes vCJD in people. The one reported case of vCJD in the United States was from a young women that contracted the disease while residing in the UK. The symptoms appeared years later after the young woman moved to the U.S.

The disease, vCJD, which primarily affects younger persons, is very hard to diagnose until the disease has nearly run its course. In its early stages, the disease may manifest itself through neurologic symptoms, but it is not until the latter stages of the disease that brain abnormalities detectable by x-ray or MRI can be seen.

Q: Is it likely I will get sick from eating beef?

A: Bovine spongiform encephalopathy has never been found in the United States. And BSE has not been found in beef muscle. So experts say beef steaks and roasts are safe, along with hamburger ground from labeled cuts, such as chuck or round.

Q: Are processed beef products riskier to eat?

A: Only slightly. Many forms of ground beef, hot dogs and luncheon meats, are made with mixed sources of meat obtained by automated equipment. These machines strip flesh from backbones and other awkwardly shaped parts of the cow. Some tests have detected central nervous system tissue in samples of processed beef products.

Q: Why is this a concern?

Resource Links

CDC - Mad Cow Q&A FDA - Mad Cow information

A: In Britain, deaths from the human form of mad cow disease were linked to eating processed products containing meat from BSE-infected animals. The disease agent concentrates in brain, spinal cord and other central nervous system tissues.

In the United States, such tissues are not supposed to be in meat products unless labeled. Industry officials say Agriculture Department tests on beef products found incidental amounts of central nervous system cells.

Q: What is the U.S. doing to ensure that beef is safe?

A: Beef imported from countries with BSE is banned, which currently includes Canada. Also banned is cattle feed made with protein or bone meal from other grazing animals. At slaughterhouses, inspectors prevent sick animals from being killed for human consumption.

Q: Is that sufficient?

A: Industry thinks so, citing eight years of BSE-free cattle here. But consumer groups say there are too many loopholes. They want wider testing and better tracking of sick animals.

Q: Why is one case of mad cow disease in Canada causing such concern?

A: The most likely cause of BSE in the Canadian animal is that it ate feed made from an infected cow years ago. If that’s true, other cattle also might be infected and they might have been processed into food for humans by accident. Or they might have been ground into animal feed that could infect other livestock that people could someday eat.