An E. coli outbreak linked to McDonald’s Quarter Pounders has led to at least 49 illnesses across 10 states, including one death. Here’s what we know. Quarter Pounders made people sick The US Centers for Disease Control and Prevention issued a food safety alert Tuesday warning that dozens of people reported eating the Quarter Pounder sandwich at McDonald’s before becoming sick.

A California grower was the source of fresh onions linked to a deadly E. coli food poisoning outbreak at McDonald's, officials with the restaurant chain said Thursday. Meanwhile, other fast-food restaurants — including Taco Bell,

Fresh onions are the likely source of an E. coli outbreak at McDonald's restaurants that has sickened 49 people and killed one, the U.S. Department of Agriculture said late on Wednesday, alarming some McDonald's customers and other fast-food chains using onions as an ingredient.