U.S. blames onions for McDonald's E. coli outbreak

U.S. health authorities said Wednesday that slivered onions used by McDonald's triggered an E. coli outbreak that sickened 90 people and an elderly man in Colorado died. These particular onions were supplied by Taylor Farms, which issued a voluntary recall. Restaurants in a dozen U.S. states temporarily pulled the burgers from their menus this month amid the outbreak linked to them.

McDonald's on Sunday said it would resume selling its Quarter Pounder hamburgers after tests for E. coli came back negative. Most E. coli are harmless and are part of a healthy intestinal tract. But some E. coli can make people sick with diarrhea, urinary tract infections, pneumonia, sepsis and other illnesses, according to the CDC.