A deadly E. coli outbreak across 10 states has been linked to McDonald’s Quarter Pounders, CDC says

• McDonald’s Quarter Pounders are making people sick with E. coli, the CDC said Tuesday.
• One person has died, and 10 others have been hospitalized after eating the hamburgers, the agency said.
• McDonald’s shares plunged in extended training on Tuesday following the announcement.

McDonald’s shares dropped more than 9% on Tuesday after the Centers for Disease Control and Prevention said one person died and 10 others were hospitalized in connection with an E. coli outbreak linked to the fast food chain’s Quarter Pounders.

The health agency said the “fast-moving” outbreak is primarily affecting people in Nebraska and Colorado. It added that most people affected reported eating a Quarter Pounder hamburger.

In an internal message published to the company’s website on Tuesday, Cesar Piña, McDonald’s North America chief supply chain officer, said the chain is taking “swift and decisive” action in response to the outbreak. The statement said the illnesses may be linked to slivered onions used in the Quarter Pounders, which are sourced by a single supplier that serves three distribution centers.

McDonald’s is temporarily removing the burgers from restaurants in Colorado, Kansas, Utah, Wyoming, and parts of Idaho, Iowa, Missouri, Montana, Nebraska, Nevada, New Mexico, and Oklahoma, the statement said,

“We take food safety extremely seriously and it’s the right thing to do,” Piña wrote.

A total of 49 cases across 10 states have been reported so far, but the extent of the outbreak is “likely much higher,” the CDC said

The CDC said McDonald’s has removed some ingredients from its burgers and paused sales of Quarter Pounders in some states. Investigators are working to determine which ingredient is making people sick.

The company’s shares plunged about 9% in extended training on Tuesday following the announcement.

McDonald’s second-quarter 2024 earnings fell 0.7% year-over-year, compared to 10.3% growth in the same period in 2023, Business Insider previously reported.

McDonald’s was in the news earlier this week after former President Donald Trump appeared at one of its restaurants in Pennsylvania on Sunday to serve customers in the swing state.

E. coli is a bacteria that can make people sick with diarrhea, urinary tract infections, pneumonia, and sepsis, the Centers for Disease Control says. Infections can happen through contact with contaminated water or food and from contact with other people or animals.

The CDC says handwashing is the best way to prevent the spread of E. coli.