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

Food safety alert

Investigation start date: October 22, 2024
Investigation status: Open
Recall issued: Yes

New as of 10/30: Fresh, slivered onions served on Quarter Pounders and other menu items from McDonald’s are the likely source of this outbreak. More illnesses have been reported, but they are from before McDonald’s and Taylor Farms took action to remove onions from food service locations. Due to the product actions taken by both companies, CDC believes the risk to the public is very low.

Fast Facts

United States
  • Cases: 90 (15 new)
  • Hospitalizations: 27 (5 new)
  • Deaths: 1 (0 new)
  • States: 13 (0 new)

New as of 10/30: Fresh, slivered onions served on Quarter Pounders and other menu items from McDonald’s are the likely source of this outbreak. More illnesses have been reported, but they are from before McDonald’s and Taylor Farms took action to remove onions from food service locations. 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. McDonald’s stopped using slivered onions on the Quarter Pounder hamburger in some states to try to prevent more people from getting sick.

Epidemiologic and traceback information show that fresh, slivered onions are the likely source of illness in this outbreak. Taylor Farms, the supplier of slivered onions to the affected McDonald’s locations also recalled onions. Food service businesses were contacted directly by Taylor Farms. The likelihood of contaminated onions still being available for sale is low.

Recalled food

Slivered onions served on McDonald's Quarter Pounder hamburgers likely made people sick.

  • Most sick people in this outbreak reported eating a McDonald's menu item containing fresh, slivered onions before they got sick.
  • McDonald's pulled fresh, slivered onions and fresh quarter pound beef patties while a specific food ingredient was being determined as the source of illness. That likely source is now believed to be onions.

Taylor Farms recalled yellow onions

  • Food service operators were contacted directly and told not to sell or serve recalled onions.
  • The onions were only distributed to food service businesses, such as restaurants. It is not likely that recalled onions went to grocery stores or directly to consumers.

What you should do

Because these onions were recalled and are no longer available for sale to food service operators, it is not necessary to avoid eating onions or other foods made with onions.

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