June 11, 2005
A U.S. meat sample that originally tested negative has been found positive for mad cow disease and has been sent to England for further testing, the U.S. Department of Agriculture said Friday night. The department insists that the meat did not enter the human food supply.
Secretary of Agriculture Mike Johanns said the sample came from a "downer" animal, meaning one that was too sick to walk. He would not say whether the animal in question had been born in the United States or imported.
The animal was first tested in November 2004 with a rapid test kit. Those results were originally "inconclusive" but were later found to be negative after more extensive testing, John Clifford, a veterinarian with USDA's Animal and Plant Health Inspection Service, said.
The sample was re-tested later by the USDA's Inspector General using a more precise method and found to be positive for bovine spongiform encephalopathy (BSE), known popularly as mad cow disease.
The first BSE-infected animal was found in the U.S. in December 2003. USDA officials said the animal had been imported from Canada and was probably infected before arriving in the U.S. The USDA would not say where the animal was found but Cattle Buyers Weekly said it was from Texas.
Johanns insisted there was no threat to human health. "This is a situation where the firewalls worked," he said. "We do not have a human health risk here."
An invariably fatal variant of BSE, Creutzfeldt-Jakob disease, can be contracted by humans who eat meat from an infected animal. So far, the degenerative brain disorder has claimed more than 150 lives -- mostly in Britain.
Mad cow disease is thought to take several years to incubate within an animal's nervous system, making young cattle less risky.
The disease can be spread through the use of animal feed made from cattle remains. In 1997, the U.S. and Canada outlawed the use of cattle remains in animal feed intended for cattle, goats and sheep.
Johanns and other USDA officials appeared primarily concerned with the effect of the latest revelation on the export of U.S. to foreign markets. Japan, Mexico and South Korea all stopped imported U.S. beef after the December 2003 BSE case. Mexico has since resumed buying U.S. beef but Japan and South Korea have not.
Japan was for many years the top U.S. export market for beef. Japanese consumer groups have lobbied against resuming U.S. beef imports, saying safety cannot be guaranteed.
Mad cow has also strained U.S. relations with Canada. The U.S. border has been closed to imports of Canadian beef since May 2003, when Canada found an animal with the disease. The USDA's plan to resume importations of Canadian beef was halted recently by a lawsuit filed by the ranchers group R-CALF USA, which said the USDA's plan was inadequate to protect the public.
More than 60 organizations are supporting R-CALF's lawsuit.
