CDC Says McDonald’s E. Coli Outbreak Kills 1 and Hospitalizes 10

An E. coli outbreak linked to McDonald’s Quarter Pounders has killed one person and hospitalized 10, according to an announcement Tuesday from the U.S. Centers for Disease Control. Forty-nine cases have been identified in 10 states, mostly in Colorado and Nebraska, dating from Sept. 27 to Oct. 11.

The CDC reports it’s not yet known which specific food ingredient in the hamburgers may have been contaminated with E. coli. McDonald’s has reportedly stopped using fresh slivered onions and quarter-pound beef patties in some states while the investigation into the source of the E. coli continues.

The CDC notes that quarter pound beef patties are only used on Quarter Pounders at McDonald’s stores, while fresh slivered onions are “primarily” used by the restaurant chain’s Quarter Pounders and aren’t included on other items. “Most people in this outbreak” have reportedly eaten Quarter Pounders, though it’s not clear precisely what percentage of those who’ve gotten sick ate that particular menu item.

While the illnesses identified so far have ranged from Sept. 27 to Oct. 11, there’s a good chance there will be more, since it typically takes 3 to 4 weeks to determine if someone who’s fallen ill is part of a specific outbreak. The CDC also notes that the true number of sick people will almost certainly be an undercount given the fact that many people recover without the need for medical care and are never tested.

The CDC included a graph in its news release showing when people were reportedly made sick.

The public health agency also included a map showing where the cases have shown up geographically. Cases have been reported in Colorado, Utah, Wyoming, Oregon, Montana, Nebraska, Kansas, Iowa, Missouri, and Wisconsin.

A number of disturbing food recalls have occurred in the U.S. in recent months, including 10 million pounds of meat and poultry from BrucePAC, which produces chicken for a number of different brands and grocery stores across the country, recalled over listeria concerns.

A major recall in frozen waffles last week over listeria concerns was expanded on Tuesday over fears pancakes and other toaster products may be affected, according to the Associated Press. The recent recalls have also affected products carried by major brands that U.S. consumers regularly rely on, including big grocery retailers like Albertson’s, Aldi, Dollar General, Kroger, Publix, Target, Walmart, among others.

McDonald’s stock price plunged 9% in after-hours trading, according to CNBC. The fast food giant did not immediately respond to questions emailed Tuesday. Gizmodo will update this post if we hear back.

This is a breaking news story and will be updated.