The list of fast-food places pulling onions over E. coli concerns just keeps growing

• Fast-food chains are pulling onions from their restaurants due to E. coli risks.
• Taco Bell, KFC, and Johnny Rockets joined McDonald's in withdrawing the ingredient from some locations.
• The outbreak linked to McDonald's involves 49 E. coli cases and one death in 10 states.

A string of American fast-food chains and restaurants are pulling fresh onions from some of their locations because of E. Coli food poisoning risks.

Yum Brands, the parent of Taco Bell, Pizza Hut, and KFC, said it was pulling the ingredient from some restaurants out of caution, the company told Bloomberg on Thursday. Yum did not specify the number or location of restaurants or specific suppliers.

On Thursday, Burger King said that it gets some of its onions from Taylor Farms, a supplier to the McDonald's restaurants that have been linked to the E. Coli outbreak.

Burger King said that it has not had any cases of illnesses or contact from authorities about whether it was impacted. But it directed outlets who received the onions — 5% of its about 7,000 outlets — to dispose of the vegetable immediately.

Fat Brands, which owns Johnny Rockets and other restaurants, also said it stopped using Taylor Farm onions on Thursday.

Burger King, Yum Brands, and Fat Brands did not respond to a request for comment sent outside business hours.

The series of withdrawals comes after 49 cases of E. coli infections and one death in a food poisoning outbreak spanning 10 US states. The Centers for Disease Control and Prevention said on Tuesday that anyone who has developed severe E. coli symptoms after eating a McDonald's Quarter Pounder should call their healthcare provider.

Public health officials are investigating which ingredient could be causing the outbreak. Early information from the FDA suggests the slivered onions or beef patties used for Quarter Pounders are the likely source of contamination.

McDonald's has temporarily pulled the Quarter Pounder from its menus in Colorado, Kansas, Utah, and Wyoming, as well as portions of surrounding states.

Other restaurants have weathered similar food-safety issues in recent years.

Outbreaks at fast-casual Mexican chain Chipotle cost the company $25 million to settle criminal charges related to outbreaks that affected 1,100 people from 2015 to 2018. The company announced a slate of new food-safety protocols in 2016 and its stock eventually recovered.

In 2022, Wendy's restaurants were linked to an E. coli outbreak in six states.

Both outbreaks involved hundreds of cases, far more than the number of people currently known to be impacted in the current McDonald's-related outbreak.

McDonald's stock price has dropped over 4% this week as news of the outbreak spreads and investors worry the cases will affect sales of the Quarter Pounder.