Health officials say that recalls of onions — the suspected source of the contamination — would help lessen the risk to consumers. Other major fast-food chains have also stopped offering onions.
The number of people hospitalized from the E. coli outbreak linked to raw onions on McDonald’s Quarter Pounder hamburgers has more than doubled, and those reporting they have been sickened rose to 75, the Centers for Disease Control and Prevention reported on Friday.
Illnesses of people ranging in age from 13 to 88 were reported in 13 states. Additionally, the C.D.C. said a second person had developed the life-threatening condition associated with E. coli called hemolytic uremic syndrome.
While cases had been originally clustered in the Mountain West, updated data from the C.D.C. now shows cases in Michigan, Washington and Oregon. It is still unclear whether those people ate at McDonald’s in their home states or stopped at one of the restaurants while traveling.
One older person in Colorado has died in the outbreak. The C.D.C. said the most recent illness occurred on Oct. 10, although the agency said more cases could be reported because it can take three to four weeks to determine whether an illness is part of the outbreak.
Federal health officials said they hoped the risk to consumers would now be lower because onions have been recalled in many of those states, and many other fast-food chains including Taco Bell, KFC, Pizza Hut and Burger King also decided to stop offering onions in their menu items as a precautionary measure.
News of the outbreak broke this week when the C.D.C. issued a food safety alert, as McDonald’s pulled its Quarter Pounders from locations in 10 states.
The fast-food chain and the Food and Drug Administration have said preliminary investigations indicated that the raw, slivered onions served mainly atop the popular quarter-pound beef patties were a “likely source of contamination.” McDonald’s has also stopped providing fresh onions on its other burger items in the region.
McDonald’s identified Taylor Farms as its onion supplier in the Mountain West and that company has since recalled several yellow onion products — slivered, diced and whole — because of “potential E. coli contamination.”
Taylor Farms, a major fruit and vegetable supplier, did not respond to repeated requests for comment.
Other restaurants that were customers and received the recalled onions have been notified and asked to remove the vegetables, the C.D.C. said.
McDonald’s has halted sales of Quarter Pounders at restaurants in Colorado, Kansas, Utah, Wyoming, Idaho, Iowa, Missouri, Montana, Nebraska, Nevada, New Mexico and Oklahoma. Other hamburger items are not affected by the outbreak, the company emphasized.
Regulators are still investigating whether the ground beef in the Quarter Pounder patties could have been a source of the bacteria.
One lawsuit has already been filed by a resident who became sick after eating at a McDonald’s in Colorado, according to the law firm Ron Simon and Associates. That state has the higher number of cases, 26, the C.D.C. said, with Montana at 13 and Nebraska 11.