NEW YORK (AP) — Big U.S. restaurant chains don’t get linked to foodborne illness outbreaks often, but the number of meals they serve causes a lot of concern when contamination of some kind sickens customers.Federal health officials identified iceberg lettuce from Mexico served at Taco Bell locations in five states as a source of widespread infections from the diarrhea-causing parasite cyclospora. A U.S. Food and Drug Administration investigation identified a single supplier as the source of the suspect lettuce.Taco Bell issued a statement on Thursday saying that “the affected ingredient from our supplier is being indefinitely removed from our supply chain nationwide and will be replaced within 24 hours in select states.” The company described the move as precautionary.A federal official who was briefed on the outbreak investigation and not authorized to discuss it identified the supplier as Taylor Farms, a company based in Salinas, California, that produces fresh vegetables for commercial use and meal kits and bagged lettuce products sold at supermarkets. Federal health officials stressed that other “brands, restaurants, retailers, or distribution channels” could be identified as the investigation continues.Here’s a brief history of some other recent outbreaks that roiled restaurant companies and sometimes changed how food safety is regulated in the U.S.