McDonald’s had stopped Quarter Pounders in select areas, and a large onion supplier issued a recall for possible E. coli contamination last week.

Burger King, Taco Bell, KFC and Pizza Hut have all pulled onions from a portion of their restaurants following reports of a “severe” E. coli outbreak linked to McDonald’s Quarter Pounders.

Big-name fast food chains, including Taco Bell, KFC, Pizza Hut, and Burger King, are reportedly pulling onions off their menus in certain locations amid a deadly, multistate outbreak of E. coli O157:H7 linked to McDonald's Quarter Pounders.