Product
A specific ingredient has not yet been confirmed as the source of the outbreak, but most sick people report eating McDonald’s Quarter Pounder burgers. Investigators are working to determine if the slivered onions or beef patties on Quarter Pounder burgers are the likely source of contamination. McDonald’s has temporarily stopped using Quarter Pounder slivered onions and beef patties in affected states. Diced onions and other types of beef patties used at McDonald’s have not been implicated in this outbreak.
Symptoms of E. coli
Symptoms begin anywhere from a few days after consuming contaminated food or up to nine days later. Symptoms include severe stomach cramps, diarrhea, fever, nausea, and/or vomiting. Some infections can cause severe bloody diarrhea and lead to life-threatening conditions, such as a type of kidney failure called hemolytic uremic syndrome (HUS), or the development of high blood pressure, chronic kidney disease, and neurologic problems.
Stores Affected
McDonald’s stores in Colorado, Kansas, Utah, Wyoming, and portions of Idaho, Iowa, Missouri, Montana, Nebraska, Nevada, New Mexico, and Oklahoma have temporarily stopped using Quarter Pounder slivered onions and beef patties.
Status
Ongoing; updates will be provided as they become available.
Recommendation
- Consumers who have already eaten at McDonald’s and have symptoms of E. coli infection should contact their health care provider to report their symptoms and receive care immediately.
- McDonald’s stores in affected states have temporarily stopped using Quarter Pounder slivered onions and beef patties. Diced onions and other types of beef patties used at McDonald’s have not been implicated in this outbreak.
Current Update
October 22, 2024
The FDA, U.S. Department of Agriculture (USDA) Food Safety and Inspection Service (FSIS), and Centers for Disease Control and Prevention (CDC), in collaboration with state and local partners, are investigating illnesses in a multistate outbreak of E. coli O157:H7 infections. A specific ingredient has not yet been confirmed as the source of the outbreak, but most sick people report eating McDonald’s Quarter Pounder burger varieties.
Investigators are working to determine if the slivered onions or beef patties on Quarter Pounder burgers are the likely source of this outbreak.
Preliminary traceback and distribution information reviewed by FDA shows that slivered onions served on Quarter Pounders are a likely source of contamination. FDA is working quickly to confirm that these onions are a source of this outbreak and to determine if these onions were served or sold at other businesses. McDonald’s has temporarily stopped using this type of onion in these states. Diced onions used at McDonald’s are not implicated in this outbreak.
FSIS is conducting traceback on hamburger patties served at McDonald’s in affected states to determine if ground beef is a source of illness. McDonald’s has also temporarily stopped selling Quarter Pounder beef patties in affected states, while the investigation is ongoing to determine the source of the outbreak.
This advisory will be updated as additional information becomes available.
Case Count Map Provided by CDC
Case Count
- Total Illnesses: 49
- Hospitalizations: 10
- Deaths: 1
- Last Illness Onset: October 11, 2024
- States with Cases: CO, IA, KS, MO, MT, NE, OR, UT, WI, and WY
Who to Contact
Consumers who have symptoms should contact their health care provider to report their symptoms and receive care.
To report a complaint or adverse event (illness or serious allergic reaction),
visit Industry and Consumer Assistance.
