Investigation start date: October 22, 2024
Investigation status: Open
Recall issued: Yes
New as of 10/25: More illnesses have been reported and everyone interviewed continues to report eating at McDonald’s before their illness started. The most recent illness started on October 10. Taylor Farms has initiated a voluntary recall of some onions sent to food service operators. Due to the product actions taken by both companies, CDC believes the risk to the public is very low.
United States
- Cases: 75 (26 new)
- Hospitalizations: 22 (12 new)
- Deaths: 1 (0 new)
- States: 13 (3 new)
New as of 10/25: More illnesses have been reported and everyone interviewed continues to report eating at McDonald’s before their illness started. The most recent illness started on October 10. Taylor Farms has initiated a voluntary recall of some onions sent to food service operators. Due to the product actions taken by both companies, CDC believes the risk to the public is very low.
Situation summary
CDC, FDA, USDA FSIS, and public health officials in multiple states are investigating an outbreak of E. coli O157:H7 infections. Most people in this outbreak are reporting eating the Quarter Pounder hamburger at McDonald’s before becoming sick. It is not yet known which specific food ingredient is contaminated.
McDonald’s is collaborating with investigation partners to determine what food ingredient in Quarter Pounders is making people sick. McDonald’s stopped using fresh slivered onions and quarter pound beef patties in several states while the investigation is ongoing to identify the ingredient causing illness.
Taylor Farms, the supplier of slivered onions to the affected McDonald’s locations, has initiated a voluntary recall and has asked customers to stop using some onions while this investigation is ongoing. Food service customers were contacted directly and told to remove onions.
Contaminated food
McDonald’s Quarter Pounder hamburgers are making people sick
- Quarter Pounder hamburgers will not be available temporarily in some states while McDonald’s makes some supply changes.
- 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 their current supply of Quarter Pounder slivered onions and beef patties.
- McDonald’s is proactively making these changes while investigators work to confirm the contaminated ingredient. Quarter pound beef patties are only used on Quarter Pounders. Fresh slivered onions are primarily used on Quarter Pounder hamburgers and not other menu items.
- Investigators are working to confirm which ingredient in these hamburgers is making people sick and if it went to other restaurants or stores.
What you should do
McDonald’s has stopped using fresh slivered onions and quarter pound beef patties in several states to protect their customers while a source of illness is confirmed.
Call your healthcare provider if you have severe E. coli symptoms:
- Diarrhea and a fever higher than 102°F
- Diarrhea for more than 3 days that is not improving
- Bloody diarrhea
- So much vomiting that you cannot keep liquids down
- Signs of dehydration, such as:
- Not peeing much
- Dry mouth and throat
- Feeling dizzy when standing up
What businesses should do
- Food service operators should not sell, eat, or serve Taylor Farms recalled yellow onions.
- Taylor Farms contacted businesses directly.
Symptoms of E. coli
- Most people infected with Shiga toxin-producing E. coli experience severe stomach cramps, diarrhea (often bloody), and vomiting.
- Symptoms usually start 3 to 4 days after swallowing the bacteria.
- Most people recover without treatment after 5 to 7 days.
- Some people may develop serious kidney problems (hemolytic uremic syndrome, also called HUS) and would need to be hospitalized.
- For more information about E. coli, see the About Escherichia coli Infection page
