Spurred by worldwide concerns about the safety of raw beef, non-profit biological-resource center ATCC is now offering strains from each of the six non-O157 Shiga toxin-producing Escherichia coli serotypes. Outbreaks of illness linked to these “Big Six” E. coli (STEC) strains have caused USDA to add them to their regimen of tests. The department has banned the sale of beef containing the presence of the STEC serogroups O26, O45, O103, O111, O121, and O145 in raw beef trimmings and other ground beef.

The six strains are rarer than the more common O157 bacteria. ATCC of Manassas, VA, is making the representative strains available for use as positive and negative controls in food QC assays. “The global community has been experiencing food-associated outbreaks of non-O157 Shiga toxin-producing E. coli for years,” says Raymond Cypess, ATCC’s CEO.