A severe E. coli outbreak linked to McDonald’s Quarter Pounder burgers has left one person dead and dozens sickened, the U.S. Centers for Disease Control and Prevention announced Tuesday.
The outbreak, which began in late September, has spread to 10 Western states, with most of the 49 cases concentrated in Colorado and Nebraska, health officials said.
Following the announcement, the fast food chain’s stock price fell more than 6% in after-hours trading.
Ten people, including one child, have been hospitalized with hemolytic uremic syndrome, a serious condition that damages blood vessels in the kidneys.
“One elderly person has died in Colorado,” the CDC said in a statement.
All of the affected individuals carried the same strain of E. coli and reported eating at McDonald’s before becoming symptomatic, specifically remembering eating a Quarter Pounder.
Investigators have not yet determined the exact ingredients responsible for the outbreak, but are focusing on sliced onions and beef patties. Both have been removed from restaurants in the affected states, pending further investigation.
“Food safety is extremely important to me and everyone at McDonald’s,” Joe Erlinger, president of McDonald’s U.S., said in a video message. “We have taken steps to proactively remove onion slices used in Quarter Pounders in some states.
“We have also decided to temporarily remove Quarter Pounders from restaurants in some states.”
He added that the majority of states were not affected. Other menu items, including other beef products, remain available in affected states.
The agency advised anyone who ingested the Quarter Pounder and developed symptoms of E. coli poisoning, including diarrhea, a fever of 102 degrees Fahrenheit (38.9 degrees Celsius) or higher, and vomiting, to seek medical attention.
Symptoms usually begin 3 to 4 days after exposure, and most people recover within 5 to 7 days without treatment. However, in some cases, the condition may become severe and require hospitalization.
