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.

McDonald’s worked Wednesday to reassure customers that its U.S. restaurants are safe as federal investigators tried to pinpoint the cause of a deadly E. coli outbreak linked to the fast-food giant's Quarter Pounder hamburgers.

McDonald's scrambled on Wednesday to contain the damage from an E. coli outbreak linked to Quarter Pounder burgers that has killed one person and sickened nearly 50 others, as it pulled the menu item from restaurants across a dozen states.