A widespread E. coli outbreak associated with McDonald’s Quarter Pounders has resulted in one death and affected at least 49 individuals across 10 states. The outbreak has prompted the first lawsuit against McDonald’s and extensive scrutiny of its onion supplier, Taylor Farms, which recently recalled potentially contaminated onions. Health officials, including the CDC, are investigating the outbreak and have confirmed that onions or beef patties may be responsible for the illnesses. Other fast-food chains, including Burger King, Taco Bell, KFC, and Pizza Hut, have also removed onions from select locations as a precaution. Consumers are urged to stay informed about symptoms of E. coli and avoid potentially contaminated products.