USDA will begin testing beef trim for non-O157 strains of E. coli on June 4, according to a notice to be published in the Federal Register. The testing will focus on six Shiga toxin-producing Escherichia coli (STEC), in addition to E. coli O157:H7.

According to the Center for Infectious Disease Research & Policy (CIDRAP), these six STEC strains account for 80 percent of non-O157 E. coli illnesses infections. The Centers for Disease Control and Prevention estimates non-O157 E. coli strains cause 112,000 illnesses annually, with about 36,700 of those attributed to beef.

Initially, USDA’s Food Safety and Inspection Service will target beef trim for testing, but plans to announce the date it intends to implement routine testing for the additional STECs in other products, including ground beef, that currently are tested for E. coli O157:H7.

Industry stakeholders have expressed concerns that USDA lacks data on the actual prevalence of non-O157 STECs on beef carcasses, and that reliable tests for the pathogens are not readily available for commercial use. In its notice, however, FSIS refutes these claims. “FSIS has concluded that a baseline is neither necessary nor warranted before implementation of the FSIS verification sampling and testing program,” the agency writes. “These organisms are present in beef products in the United States.”

FSIS does, however, plan to conduct a carcass baseline survey next year, which will analyze samples from pre-treated carcasses for the presence of the pathogens E. coli O157:H7 and the specified STECs, Salmonella, and indicator bacteria (generic E. coli, coliforms, and Enterobacteriaceae). As it plans the research, FSIS will share the study design with stakeholders.

As for the logistics of testing, FSIS says screening and confirmation methods and materials for non-O157 STEC are available to industry. Some establishments have been testing for non-O157 STECs for a year or more. Also, FSIS has reviewed validation data from test kits from several manufacturers and issued no-objection-letters for their commercial use.

In related news, USDA’s Office of the Inspector General this week released results of an audit of beef plants, outlining the industry’s aggressive efforts to protect the beef supply from E. coli contamination.

"We found that industry was performing thousands of E. coli tests daily generally following the Food Safety and Inspection Service’s recommended procedures.  Overall, industry was taking  appropriate steps to help ensure that U.S. beef is safe from E. coli contamination, recognizing  that regardless of how stringently the industry tests for E. coli, there is always an inherent risk of  its presence in slaughter plants,” the report concludes.

The audit report is available online from USDA.

Read the Federal Register notice regarding STEC testing for beef.