The claim that McDonald’s is resuming sales of Quarter Pounders after testing ruled out beef patties as the source of an E. coli outbreak is accurate. The U.S. FDA has indicated that slivered onions from a specific supplier are likely responsible for the contamination. McDonald's has stated that they will sell the Quarter Pounder without slivered onions at affected locations. The outbreak has affected at least 75 people across 13 states, leading to one death and multiple hospitalizations, with the majority of cases linked to onions sourced from Taylor Farms' Colorado facility. Testing by Colorado agriculture officials confirmed that the beef patties tested negative for E. coli. While it remains unclear if the recalled onions are definitively the source of the outbreak, McDonald's has ceased sourcing from that facility.