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Testing for new E. coli strains in beef finally to begin

Barring any last-minute delays, U.S. food safety inspectors will begin testing Monday for six new strains of potentially deadly E. coli bacteria to be banned from certain cuts of raw beef.

The move implements long-delayed federal regulations aimed at a group of E. coli bacteria collectively known as “the Big Six,” bugs capable of causing severe infection and death.

Under the new rules, the six additional strains of E. coli will be classified as adulterants on par with the better-known E. coli O157:H7, which is often linked to serious illnesses tied to hamburger. The new strains include E. coli O26, O111, O103, O121, O45 and O145.

Meat producers such as Cargill Inc., who have long opposed expanded testing, said they are ready to begin.

“We are prepared for USDA to collect whatever samples they wish to collect for non-O157 STEC sampling at our beef harvesting (slaughter) facilities starting June 4,” Cargill spokesman Michael Martin wrote in an email to

Beginning Monday, it will be illegal to sell raw beef trimmings and non-intact beef products, such as tenderized steaks, if they’re contaminated with any of the six new strains of E. coli, according to documents from the Food Safety and Inspection Service of the U.S. Department of Agriculture.

The agency indicated it plans in the future to expand routine testing for those strains to additional raw beef products, including ground beef.

Like E. coli O157:H7, the six new strains are capable of producing bloody diarrheal illness that can lead to kidney failure and death. In 2010, for the first time, the non-O157 strains of what are known as Shiga toxin-producing E. coli, or STECs, were responsible for more infections in the U.S. than E. coli O157:H7, according to federal health officials.

The non-O157 STECs caused 451 confirmed infections that year, including 69 people who were hospitalized and one death. E. coli O157:H7 caused 442 infections, 184 hospitalizations and two deaths, according to the Centers for Disease Control and Prevention. Many illnesses are never reported, however, and the agency estimates that non-O157 E. coli strains cause an estimated 113,000 illnesses and 300 hospitalizations a year.

The new rules were announced last September by Dr. Elisabeth Hagen, the USDA’s undersecretary for food safety. Testing originally was set to begin in March. The most recent delay was only the latest in a saga that started in 2007, when food safety advocates and federal officials first began discussing whether the lesser-known strains of E. coli should be regarded as adulterants, too.

Meat industry officials vehemently opposed the move, saying that current efforts to identify E. coli O157 were adequate to screen for the other strains as well.

“The science tells us that the food safety protocols and interventions we have in place for E. coli O157:H7 also mitigate the other six STECs,” Martin wrote.

Beef importers from outside the U.S. also objected, saying the new regulations would impede trade. 

Some in the meat industry already were testing for the non-O157 STECs. Costco already tests for the pathogens. Also, Beef Products Inc., the South Dakota firm at the center of the "pink slime" scandal, has long tested its lean finely textured beef products for the presence of the additional strains of E. coli in addition to O157:H7. Spokesman Craig Letch said that practice continues, even after the company shuttered three of its four plants.

The new testing requirement is a victory for Bill Marler, a Seattle food safety lawyer who petitioned FSIS to have the “Big Six” strains declared adulterants and then threatened to sue the USDA when the agency didn’t respond promptly.

He pointed to the 1994 classification of E. coli O157:H7 as an adulterant as a turning point for food safety in U.S. and said the new rules would have a similar effect.

“(It) dramatically changed the landscape of how safe our meat supply is for the better,” he said. “This is another step in getting this done correctly.”

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