The U.S. government said Tuesday it has closed its investigation into an E. coli outbreak tied to McDonald’s Quarter Pounder hamburgers after determining there is no longer a safety risk.
The outbreak, which was first reported Oct. 22, sickened at least 104 people in 14 states, including 34 who were hospitalized, according to the U.S. Food and Drug Administration. One person in Colorado died and four people developed a potentially life-threatening kidney disease complication.
The FDA, which conducted the investigation along with the U.S. Centers for Disease Control and Prevention and state health departments, linked the outbreak to yellow onions distributed by California-based Taylor Farms and served raw on Quarter Pounders at McDonald’s restaurants in Colorado, Kansas, Wyoming and other states. Taylor Farms initiated a voluntary recall of yellow onions on Oct. 22.
Federal and state health officials in Colorado didn’t find the strain of E. coli that caused the illnesses in onions it tested or in any samples from the environment. But they concluded that evidence showed that recalled yellow onions were the likely source of the outbreak.
“McDonald’s is no longer serving recalled onions and there does not appear to be a continued food safety concern related to this outbreak,” the FDA said Tuesday in a statement.
McDonald’s briefly pulled Quarter Pounders from 3,000 U.S. stores as a result of the outbreak, then narrowed that to 900 stores once testing had pinpointed onions — and not hamburger patties — as the likely source of E. coli. The company found an alternate supplier and resumed selling Quarter Pounders with slivered onions at all U.S. stores last month.
But the outbreak has hurt demand. In mid-November, McDonald’s said it planned to spend $100 million to bring customers back to stores, including $65 million that will go directly to the hardest-hit franchisees.
Chicago-based McDonald’s wouldn’t say Tuesday whether its sales have returned to normal levels in the affected regions. But it thanked U.S. regulators for their quick action and said it remains confident in its rigorous food-safety standards.
McDonald’s last major food-safety issue happened in 2018, when more than 500 people contracted an intestinal illness after eating its salads.
McDonald’s also declined to comment Tuesday on legal action against the company as a result of the E. coli outbreak.
Nicole and Richard West of Townsend, Montana, are suing McDonald’s after their 11-month-old daughter, Logan, was hospitalized in October with E. coli poisoning. The toddler ate a few bites of her father’s Quarter Pounder hamburger with onions during a family road trip on Oct. 2.