April 4, 2001 (Washington) -- The U.S. remains free of both "mad cow" disease and its dreaded human counterpart, but additional precautions are crucial, experts warned at a Senate hearing today.
Mad cow disease, known formally as bovine spongiform encephalopathy (BSE), is a fatal brain-wasting condition that was first diagnosed in British cattle in 1986. It's now been found in native cattle in Belgium, Denmark, France, Germany, Ireland, Italy, Liechtenstein, Luxembourg, the Netherlands, Portugal, Spain, and Switzerland.
The human version of mad cow disease is a variant of the fatal Creutzfeldt-Jakob disease (CJD). It's believed to be contracted by eating certain parts of infected cattle. Some 97 people in the U.K. have died from this version of CJD, along with a few more individuals in mainland Europe.
Millions and millions of European cows have been destroyed as the affected countries race to remove the risk of human infection.
Several senators expressed concern on behalf of Americans who may be afraid of European travel, given the long-simmering beef scare.
But Richard Johnson, MD, a special disease adviser to the National Institutes of Health, noted that the numbers of infected cattle have plummeted in the U.K. and that fewer than a handful of human cases have been reported in other European countries. As for the risk of traveling to Europe and eating European beef, he said, "The danger of driving to the airport is probably greater."
The U.S. risk for any kind of BSE spread -- cattle or human -- is "very low" but "not zero," said disease expert Will Hueston, associate dean of the Virginia-Maryland Regional College of Veterinary Medicine.
"Importation of affected animals and contaminated products of animal origin, such as meat and bone meal, represent the greatest risk for introduction of BSE to the U.S.," Hueston said.
Through restrictions going back to 1989, the U.S. has banned imports of cows and other cud-chewing animals from countries with the disease, as well as feed and other products derived from these animals. In 1997, the government banned the use of most cattle feed that contains animal protein. In Europe, BSE is believed to have spread through feed that contains tissue from infected cows. The U.S. government also is monitoring the nation's cattle herds, but examination of more than 12,000 suspect cows has thus far turned up no signs of the infection.
Hueston tells WebMD that more prevention steps are warranted, including better diagnostic laboratories and increased spending in BSE research, along with better processes to identify and test high-risk cattle here.
Sen. Dick Durbin, (D-Ill.), said he planned to introduce legislation to tighten various precautions and install new safeguards. Sen. Ben Nighthorse Campbell, (R-Colo.), already has unveiled a bill that would set up a federal task force to coordinate prevention efforts.
Lawmakers at today's hearing agreed that further steps are important to maximally ensure safety.
"While the risks may be low, we cannot be complacent," said Sen. Peter Fitzgerald, (R-Ill.), chairman of the panel. "We need to do a lot in a lot of areas," said Sen. Byron Dorgan, (D-N.D.). Added Sen. Sam Brownback, (R-Kan.), "If we take the right steps, it's not going to get to America."
Some critics note that even the existing restrictions may not be fully effective. In a recent survey, the Center for Science in the Public Interest (CSPI) noted the FDA found that more than 20% of feed mills didn't have a system to prevent co-mingling of feed lots and subsequent possible consumption of infected feed by cattle. But the agency said today that new inspections have seen a dramatic improvement in standards at the lots.
CSPI also noted that gelatin, which is used in flavored deserts and gummy candies, is an animal protein from cow and pig hides and bones. Risks of BSE infection from hides and bones appear very low, but the FDA has thus far simply asked that gelatin makers not use cow parts from countries that have had the disease.
Meanwhile, the consumer advocacy group Public Citizen expressed concern about dietary supplements, since some products contain extracts from cow glands. Some supplement firms now say that they are not using cow organs from countries with BSE, but the FDA lacks the authority to monitor what actually goes into the products.
"The agent that causes BSE has often found a way to pierce small chinks in the public health armor," warned Public Citizen's Peter Lurie, MD.