The USDA Food Safety Inspection Service (FSIS) this week implemented routine verification testing for six added Shiga toxin-producing Escherichia coli (STEC) pathogens. The new targets are in addition to long-standing test requirements for serotype E. coli O157:H7
Shiga toxin-producing Escherichia coli is a type of enterohemorrhagic E. coli (EHEC) bacteria that can cause illness ranging from mild intestinal disease to severe kidney complications. There are more than 100 non-O157 strains. While most strains are harmless, some strains are highly pathogenic. STEC may cause illnesses of varying severity, from diarrhea and abdominal cramps to, rarely, kidney disorders.
Shiga toxin is the same toxin as is produced by Shigella, the bacteria that cause dysentery. In some instances, the toxin will bind to tissues in the kidneys and cause hemolytic uremic syndrome (HUS), leading to kidney failure and death.
The new targets include the most prevalent pathogenic non-O157 STEC serogroups in the United States: O26, O45, O103, O111, O121 and O145. While more than 50 STEC serogroups have been associated with human illness, CDC data shows that over 70 to 83 percent of confirmed, serogrouped non-O157 STEC illnesses are caused by these six STEC. All of these strains can cause hemorrhagic colitis and all except O45 have been shown to cause hemolytic uremic syndrome.
FSIS announced plans for the increased testing in 2011, after a number of years of pressure from consumer advocacy groups including petitions filed by the law firm Marler-Clark, L.L.P.
This initial implementation of the testing will only include imported raw beef manufacturing trimmings. First year testing will involve screening phases that allow the processors the opportunity to improve their food safety systems and to help with the transition to the enhanced testing.
The agency is planning to expand testing in the future, including looking for the Non-O157 targets in other ‘non-intact’ products such as ground beef.