FDA Provides Update on E. coli STEC Outbreak Associated with Onions

FDA provided an update on the E.coli STEC linked to onions served on fast food chain hamburgers.  There are now 104 cases with 34 hospitalizations and one death.  That is over 15 more cases from the last update on October 30.

FDA provided this about the investigation - "At this time, one FDA sample of recalled onions has tested positive for E. coli, but it is a non-O157:H7 Shiga toxin-producing E. coli (STEC) and does not match the outbreak strain or any other clinical illnesses. Whole genome sequencing (WGS) analysis determined that the sample is positive for E. coli O168:H8 and contains the Shiga toxin gene stx2a. Additional sample results are pending. More information will be provided in this update as it becomes available."

Case Count
Total Illnesses: 104
Hospitalizations: 34
Deaths: 1
Last Illness Onset: October 21, 2024
States with Cases: CO, IA, KS, MI, MO, MT, NE, NM, NC, OR, UT, WA, WI, and WY
Recalled Onion Distribution*: CO, IA, ID, KS, MO, MT, NE, NM, NV, OK, UT, and WY
*Distribution has been confirmed for states listed, but product could have been distributed further, reaching additional states.


https://www.fda.gov/food/outbreaks-foodborne-illness/outbreak-investigation-e-coli-o157h7-onions-october-2024
Outbreak Investigation of E. coli O157:H7: Onions (October 2024)
FDA’s investigation and sample analysis are ongoing.

Product

Slivered onions previously served on McDonald’s Quarter Pounder burgers are the likely source of contamination, based on epidemiologic and traceback data. On October 22, 2024, Taylor Farms initiated a voluntary recall of yellow onions sent to McDonald’s and other food service customers. Food service customers who were impacted have been contacted directly. McDonald’s stopped using recalled onions from Taylor Farms at McDonald‘s stores in affected states.

Current Update

November 13, 2024

FDA, CDC, and state partners continue investigating a multistate outbreak of E. coli O157:H7 linked to slivered onions served on Quarter Pounder burgers at McDonald’s restaurants in certain states. As of November 13, 2024, 104 people infected with the outbreak strain of E. coli O157:H7 have been reported from 14 states. Of 98 people with information available, 34 have been hospitalized, and 4 people developed HUS, a serious condition that can cause kidney failure. One death has been reported from an older adult in Colorado. This person is not one of those who developed HUS. Of the 81 people interviewed, 80 (99%) report eating at McDonald's. Seventy-five people were able to remember specific menu items they ate at McDonald's. 63 of 75 people (84%) reported a menu item containing fresh slivered onions.

FDA, Colorado Department of Agriculture (CDA), and Colorado Department of Public Health and Environment (CDPHE) have collected onion and environmental samples from McDonald’s stores, distribution centers, and firms of interest for laboratory analysis. At this time, one FDA sample of recalled onions has tested positive for E. coli, but it is a non-O157:H7 Shiga toxin-producing E. coli (STEC) and does not match the outbreak strain or any other clinical illnesses. Whole genome sequencing (WGS) analysis determined that the sample is positive for E. coli O168:H8 and contains the Shiga toxin gene stx2a. Additional sample results are pending. More information will be provided in this update as it becomes available.

FDA has completed onsite inspections at a Taylor Farms processing center in Colorado and an onion grower of interest in Washington state.

McDonald’s stopped using slivered onions on Quarter Pounder burgers in affected states, and Taylor Farms recalled yellow onions on October 22, 2024. Food service customers were notified by Taylor Farms that they should not sell or serve recalled yellow onions. FDA continues working with Taylor Farms and their direct customers to determine if additional downstream customer recalls are necessary. Food service customers should not be further distributing recalled onions. According to available information, recalled onions should not be available for purchase in grocery stores. McDonald’s has reintroduced slivered onions from a different onion supplier into their full menu. At this time, there does not appear to be a continued food safety concern related to this outbreak at McDonald’s restaurants.