CDC Investigates E. coli Outbreak Linked to Onions Served at McDonald’s

The Centers for Disease Control and Prevention (CDC) is currently investigating a multistate outbreak of E. coli O157:H7 infections linked to fresh, slivered onions served at McDonald's restaurants. As of the latest update, a total of 104 people infected with the outbreak strain have been reported from 14 states, with illnesses starting from September 27, 2024, to October 11, 2024.

Epidemiologic and traceback information indicate that the fresh, slivered onions served on McDonald’s Quarter Pounder hamburgers are the likely source of the outbreak. Most people in this outbreak reported eating a Quarter Pounder hamburger at McDonald’s before becoming sick. The CDC, FDA, USDA-FSIS, and public health officials in multiple states are collaborating on the investigation.

The outbreak has resulted in 27 hospitalizations and one death, with one person developing hemolytic uremic syndrome (HUS), a serious condition that can cause kidney failure. To mitigate the risk, McDonald’s has stopped using fresh slivered onions and quarter pound beef patties in several states, and Taylor Farms, the supplier of the onions, has recalled the affected onions.

The CDC advises individuals who have eaten at McDonald’s and are experiencing severe E. coli symptoms, such as diarrhea and a fever higher than 102°F, bloody diarrhea, or signs of dehydration, to contact their healthcare provider immediately.