The U.S. Department of Agriculture’s Food Safety and Inspection Service is planning to expand testing for six non-O157 strains of Shiga toxin-producing E. coli (STEC) – just recently declared adulterants – to more beef products next year.
According to Meatingplace (subscription only), FSIS official Emilio Esteban told a North American Meat Association conference Wednesday, “We are expecting to expand beyond (testing) trim sometime in 2013.”
The report noted that, at the same conference, which was focused on E. coli, Acting Assistant FSIS Administrator Office of Policy and Program Development Rachel Edelstein did not speculate on exactly which products FSIS would test next. Edelstein added that FSIS would have to send any changes to the White House Office of Management and Budget for a cost-benefit analysis before they could take effect.
FSIS officials also said the agency would continue trying to get the most out of each sample collected.
“As such, we may consider testing the same sample for other microorganisms. Any change will be announced prior to implementation,” said Esteban, according to the report.
While public health officials mull their next step on testing, a new study published in the Dec. 2012 Journal of Food Microbiology found a significant STEC contamination rate among meat products sampled at Washington, DC area grocery stores.
Conducted by researchers at the University of Maryland, the U.S. Department of Agriculture’s Center for Veterinary Medicine and the Chinese College of Food Science in Engineering, the study tested 480 samples of meat, including 249 of ground beef and 231 of ground pork. In all, STEC were isolated from 13 – or 5.2 percent – of the beef samples, and 12 – or 5.2 percent – of the pork samples. Multiple STEC isolates were found in some samples. In total 32 isolates were recovered, 16 from beef and 16 from pork.
The researchers also looked at antimicrobial susceptibility. Among the 32 isolates, 18 – or 56.3 percent – were resistant to at least one antimicrobial. More pork than beef isolates showed resistance. A full 75 percent of the pork isolates were resistant to at least one antimicrobial. More than half of all isolates were resistant to at least two antimicrobials.
The paper hints that antibiotic use in pork production may play a role in the increased rate of resistance: “A greater resistance level was found in STEC from ground pork than from ground beef. This is likely due to differences in animal husbandry practices in the raising of hogs and cattle for meat.”
According to the study, previous research on STEC in ground beef has shown that the prevalence of non-O157 STEC can range from 2.4 to 30 percent.
The researchers also cited a U.S. study that found 7.3 percent of ground beef to be positive for non-O157 STEC. One study commissioned by Food Safety News‘ publisher Bill Marler found that around 1.9 percent of meat sold in grocery stores tested positive for STEC. Another study from Texas Tech University found 4.11 percent of whole meat cuts sold at retail locations were similarly contaminated.
So far, FSIS is only testing for the “Big Six” E. coli strains in beef trim from slaughterhouses, not in meat that has been processed into a finished ground beef product. The new testing also excludes bench trim and meat from the cow’s head and cheek. But, as Meatingplace reports, that may be about to change.