Foodborne illness outbreaks have repeatedly disrupted U.S. restaurant chains, triggering recalls, lawsuits, and heightened regulatory ‌scrutiny while pressuring customer traffic and sales.

The U.S. Food and Drug Administration said Thursday that Taco Bell, owned by Yum Brands, will stop using lettuce from a supplier the agency has linked to an ongoing cyclosporiasis outbreak.

The business impact of such outbreaks has varied widely.

Analysts at ‌TD Cowen wrote last week that similar food safety issues at McDonald's ​in late 2024 only impacted the chain for a quarter, while the Wendy's episode in 2022 saw no discernible impact at all.

But ⁠previous outbreaks in 2015 at Chipotle Mexican Grill and in 1993 at Jack ​in the Box caused sales at those companies to drop sharply for several quarters.

Below ⁠is a look at major foodborne illness outbreaks and contamination scares that have affected U.S. restaurant and food companies in recent years.