USDA Finds Low Prevalence of Mad Cow Disease in United States

By Kathryn McConnell
Washington File Staff Writer

Washington - Following nearly two years of extensive testing, the U.S. Department of Agriculture (USDA) has concluded that the prevalence of bovine spongiform encephalopathy (BSE), or mad cow disease, in the United States is "extraordinarily low."

Briefing reporters April 28, Agriculture Secretary Mike Johanns said test results of nearly 650,000 "high-risk" cattle since June 2004 indicate that the prevalence of BSE in the U.S. cattle herd is no more than four to seven cases.

The U.S. cattle population encompasses approximately 42 million animals, according to USDA.

The department now will submit its analysis of test results to an independent committee of scientists for "rigorous review." The results include those from testing over the five years immediately prior to the start of the enhanced surveillance program, Johanns said.

Cattle considered high-risk are adult animals showing clinical signs of illness related to the central nervous system, those that cannot stand and those that have died, according to USDA.

Under the enhanced testing program samples were taken at more than 5,700 sites - farms, slaughterhouses and rendering facilities - located throughout the United States.

USDA implemented the enhanced BSE surveillance program in response to a December 2003 discovery of the first case of BSE in the United States. (See related article.)

Following the committee's review of the report, USDA will determine how many head of cattle it will continue to test annually. Johanns said he expects the number will be considerably lower than the total tested during the 2004 and 2005.

USDA is working to develop "what we think would be an appropriate level of maintenance testing … making sure it is scientifically and statistically valid," said Ron DeHaven, administrator of the department's Animal and Plant Health Inspection Service (APHIS).

The USDA testing during the enhanced period exceeded standards set by the World Organization for Animal Health, Johanns said.

He said he believes USDA's analysis will be well received by Japan and other trading partners that have banned U.S. beef.

Johanns said he will meet with Japan's agriculture secretary the first week of May in Geneva to discuss restarting U.S. beef exports to Japan.

Japan, which had been the top importer of U.S. beef in 2003, initially banned U.S. beef imports after the first BSE case was found. It then started accepting U.S. beef again in December 2005 but reimposed the ban over renewed fears of BSE after its inspectors found a shipment of U.S. beef containing prohibited spinal column cattle parts. (See related article.)

A second measure used to prevent the spread of BSE among cattle in the United States is a ban on feed containing material derived from slaughtered cows or other ruminants imposed by the Food and Drug Administration (FDA) in 1997, Johanns noted. Other countries, including Canada, that have similar bans also have seen the incidence of BSE in their cattle populations, he said.

A third measure is a system to track livestock from birth through slaughter called the National Animal Identification System (NAIS).

On another export issue, Johanns said Russia's April 27 cancellation of U.S. poultry imports shipped after May 8 was unexpected.

"I was extremely disappointed by the Russian action; there was literally no notification," he said.

Russian poultry farmers had been calling for import restrictions, according to news reports.

Russia had been the largest buyer of U.S. poultry with sales worth more than $600 million annually, Johanns said.

A press release about the prevalence estimate, the analysis and a summary (PDF, 23 pages) of the testing are available on the USDA Web site.