Ars Scientists Uncover Details Underlying Seasonal Outbreaks

E. Coli Outbreak Linked to Romaine Lettuce at Wendy's Restaurants

ARS Scientists Uncover Details Underlying Seasonal Outbreaks

47 More Illnesses Reported Since Last Update

Agricultural Research Service (ARS) scientists have uncovered details underlying a pattern of seasonal E. Coli O157H7 outbreaks linked to bagged salad mix, including romaine lettuce. Since the last update on August 19, 2022, 47 more illnesses have been reported to the Centers for Disease Control and Prevention (CDC), bringing the total number of people infected with the outbreak strain of E. coli O157 to 84.

While romaine lettuce at Wendy's restaurants is the suspected cause of the outbreak, it has not yet been confirmed. The investigation is ongoing to determine the specific food source and whether the lettuce used at the Wendy's stores was served or sold at other locations.

ARS scientists have found that the seasonal outbreaks are linked to the presence of a specific type of E. coli O157H7 that is particularly well-suited to surviving and multiplying in the cold temperatures of bagged salad mix. This type of E. coli is also more likely to produce toxins that can cause severe illness in humans.