More mad cow cases likely, experts say
There is a "high probability" that more cases of bovine spongiform encephalopathy exist in the United States, an international board of experts told Agriculture Secretary Ann Veneman on Wednesday.
Veneman's Advisory Committee on Foreign Animal and Poultry Diseases met in a closed session Thursday to assess the board's report. The board was convened to critique the agency's response to last December's discovery of the nation's first case of BSE, or mad cow disease. If Agriculture Department officials accept the board's findings and recommendations, it would spell sweeping changes for farmers and ranchers and the industries that manufacture animal feed, slaughter cattle and render their carcasses, as well as for federal officials who regulate and inspect those industries.
The board praised the actions taken thus far by the Agriculture Department, and said there was little threat to human health. Nonetheless, board members were unanimous in their conclusions that the disease is more prevalent than U.S. officials now believe, and they recommended significant changes to U.S. feed manufacturing and animal-processing practices. The board was composed of two members from Switzerland and one each from the United Kingdom, New Zealand and the United States. All of the members have had extensive experience with BSE, which was first diagnosed in Britain in the mid 1980s and then spread to Europe. The disease devastated the British beef industry.
The board's recommendations will undoubtedly face significant resistance. Before the report was even presented to Veneman, the National Cattlemen's Beef Association issued a press release questioning the science behind the report.
"Many of the panel's recommendations are based on the European model and overlook scientific evidence that clearly demonstrates the long-standing firewalls in place in our country that have been effective," said Dr. Gary Weber, the association's director of regulatory affairs.
BSE is not a contagious disease and cannot spread directly from one animal to another. It is spread through feed that has been infected with the agent that causes BSE. Meat even from diseased cattle is considered safe, but it can become contaminated in the slaughter and rendering process if it is exposed to cattle parts-mainly the brain and spinal column-that carry the agent that causes BSE. Humans eating contaminated meat are at risk for developing Cruetzfeldt-Jakob disease, a rare, degenerative neurological disease. For that reason, the Agriculture Department, which regulates meat processing, and the Food and Drug Administration, which regulates animal feed production, have recently tightened measures aimed at preventing the spread of BSE through meat and feed processing operations.
The board recommended that the U.S. consider banning all mechanical deboning and tissue-processing methods.
The Holstein cow in Washington State discovered to have BSE, was imported from Canada, which reported its first case of BSE last spring. Ulrich Kihm, the Swiss board member who presented the panel's findings to Veneman's advisory committee, said it is likely that the U.S. has imported other infected animals from Canada and that infectious material has been cycling through animal feed for many years.
Kihm cautioned against thinking that BSE was a Canadian problem: "You cannot separate Canada from the United States when you look at trade."
He also recommended that the U.S. reconsider the effect of its recent ban on allowing downer cattle to enter the food supply. Downer cattle are incapable of walking on their own, either due to disease or injury, and are considered at the highest risk of carrying BSE. For that reason, the government's surveillance program for detecting BSE was focused on testing downer cattle after they were slaughtered (testing for BSE can only be done after an animal is dead).
Before the ban went into effect Dec. 30, 2003, federal food safety inspectors discovered most downer cattle when they showed up at the slaughterhouse. Even those downer animals deemed unfit for human food were typically slaughtered and processed for other uses. Since the ban went into effect, however, many farmers are no longer bringing those animals to the slaughterhouse, which presents a major challenge for federal inspectors, who now must seek out downer cattle on farms for BSE testing. Jim Rogers, a spokesman for USDA's Animal and Plant Health Inspection Service, says agency officials are still trying to figure out how they will track downer cattle for BSE testing. Officials must give farmers an incentive for reporting downer cattle so they can be tested, Kihm says, otherwise the U. S. will lose the ability to test those animals and therefore gather valuable data about the prevalence of the disease. In addition, the fear that downer cattle may test positive for BSE could drive farmers to dispose of those cows in ways that are harmful to other animals or humans. There is already anecdotal e evidence that rendering facilities, which process animal carcasses after the meat has been removed, are rejecting some carcasses that are being tested for BSE, because plant owners fear a positive test will have serious economic consequences for them if they are forced to recall products.
"You must beware of unintended consequences of decisions," Kihm said. "We in Switzerland have been through this. We know how difficult this will be for the United States."