CHRONOLOGY- Mad Cow Disease in The United States
Date: 14-Jun-05
Country: USA
The only US confirmed case of mad cow disease, or bovine spongiform encephalopathy, was found in December 2003 in a Washington state dairy cow.
The following is a chronology of mad cow disease in the United States.
Dec. 23, 2003
The US Department of Agriculture announces the first confirmed US case of mad cow disease and quarantines a 4,000-animal herd in Mabton, Washington, where an infected Holstein dairy cow's yearling calf lives.
Investigators later determine the animal was born in April 1997 in Alberta, Canada, and exported to Washington state in September 2001, with a herd of some 81 dairy animals.
Dec. 24
Some 10,000 pounds (4,535 kg) of meat are recalled by Vern's Moses Lake Meats, where the animal was slaughtered.
Dec. 30
USDA announces immediate ban on downer cattle in human food supply and a ban on the brains, eyes and small intestines of older animals for the human food supply.
USDA bans air injection stunning at slaughter plants and bans "mechanically separated" meat in human food.
USDA orders plants using advanced meat recovery technology to ensure no spinal cord slips into ground beef. Cattle being tested for mad cow will be held from further processing until test results are returned.
Jan. 26, 2004
The Food and Drug Administration bans cattle blood as a protein supplement for calves and chicken litter as cattle feed, and orders downer cattle kept out of dietary supplements and cosmetics. Consumer groups urge the FDA to ban all animal protein from all animal feed, including rations for poultry, pigs and household pets.
Feb. 4
International expert panel finds "high probability" that more cases of mad cow disease exist in American cattle.
Panel recommends FDA ban on cattle brains and spinal material from all livestock feed and from pet food, and ban on all animal protein such as meat and bone meal from cattle feed to prevent cross-contamination. Panel recommends the USDA ban from human food the brain and spinal cords from all cattle older than 12 months, replacing the current ban on material from cattle older than 30 months. Panel also urges the USDA randomly test some healthy cattle.
Feb. 9
USDA ends Washington state mad cow investigation after checking the identities of some 75,000 cattle to find the herdmates of the infected cow. Of the 80 herdmates shipped to the United States in September 2001, the USDA located 28.
March 19
Canadian Food Inspection Agency says the US case and a Canadian mad cow case diagnosed in May 2003 were probably caused by contaminated feed. Both animals were born in the spring of 1997 in Canada. The agency did not identify two Canadian feed mills that sold feed to the two infected calves.
June 25
USDA reports first "inconclusive" test result for mad cow disease since it began using rapid screening test kits on June 1. Animal later retested and found negative.
June 29
USDA says second animal tested "inconclusive" with rapid screening test kits. Animal later retested and found negative.
Nov. 18
USDA says the animal has two preliminary tests that are "inconclusive" for mad cow disease. More sophisticated test ordered.
Nov. 23
Suspect animal tests negative after two immunohistochemistry, or IHC tests, considered the "gold standard" by the USDA.
The department expresses confidence the animal does not have mad cow disease.
Feb. 24, 2005
Consumers Union urges the USDA to retest the suspect animal, using an even more sophisticated test called the "Western blot" test.
Scientists in Japan and Belgium have reported that suspect cows may be negative on the IHC and still register as positive on the Western blot, the consumer group said.
Week of June 5 -- USDA's Office of Inspector General recommends the retesting of the suspect animal using the Western blot test due to the discrepancy between the rapid test kits and the IHC.
June 10 --