March 1, 2004 Consumer Reports On Health

Does this disease occur only in cattle? There are several similar fatal brain diseases known as transmissible spongiform encephalopathies. The disease in people is called Creutzfeldt-Jakob disease, or CJD; in cows it's called mad-cow disease; in sheep it's scrapie; and in deer and elk, chronic wasting disease. All are believed to be caused by a mutant protein, or prion, that induces normal proteins to mimic its shape. The disease can be transmitted when a diseased animal is eaten.

Can proper cooking protect you? No. Cooking meat until it's well-done will protect against bacteria but not infectious prions, which are highly resistant to heat.

Is it safe to eat U.S. beef? The extent of the risk of human infection is likely to remain unknown for some time. Individuals need to make a judgment about their risk tolerance. If eating beef is not very important to you, you might want to forgo it until more is known. If you want to eat beef, you can limit your risk by avoiding the foods that are most likely to carry mad-cow disease: brains and processed beef products that may contain nervous-system tissue, such as hamburger, hot dogs, and sausage. Hamburger that is ground while you watch is lower-risk. Beef labeled "organic" or "biodynamic" carries the least risk; inspections confirm that the cattle are not fed animal remains.