LOS ANGELES -- McDonald's announced Sunday that Quarter Pounders will again be on its menu at hundreds of its restaurants after testing ruled out beef patties as the source of the outbreak of E. coli poisoning tied to the popular burgers that killed one person and sickened at least 75 others across 13 states. The U.

S. Food and Drug Administration continues to believe that slivered onions from a single supplier are the likely source of contamination, McDonald's said in a statement. It said it will resume selling the Quarter Pounder at affected restaurants -- without slivered onions - in the coming week.

As of Friday, the outbreak had expanded to at least 75 people sick in 13 states, federal health officials said. A total of 22 people had been hospitalized, and two developed a dangerous kidney disease complication, the Centers for Disease Control and Prevention said. One person has died in Colorado.

Early information analyzed by the FDA showed that uncooked slivered onions used on the burgers "are a likely source of contamination," the agency said. McDonald's has confirmed that Taylor Farms, a California-based produce company, was the supplier of the fresh onions used in the restaurants involved in the outbreak, and that they had come from a facility in Colorado Springs, Colorado. McDonald's pulled the Quarter Pounder burger from menus in several states - mostly in the Midwest and Mountain states - when the outbreak was announced Tuesday.

McDonald's said Friday that slivered on.