Health Officials Trace Parasite Outbreak to Restaurant Chain's Lettuce Supply

Health investigators have linked a multi-state outbreak of cyclosporiasis, a gastrointestinal illness caused by a microscopic parasite, to shredded lettuce served at a fast-food chain, prompting the company to pull the affected product from its supply chain. The outbreak has sickened well over a hundred people across more than a dozen states, with symptoms including diarrhea, cramping, nausea and fatigue that investigators say can persist for weeks if untreated. Unlike many foodborne pathogens, cyclospora spreads through contaminated food or water rather than person-to-person contact, which investigators say has helped narrow the search for a common source. Public health officials said they are continuing to trace the lettuce supply chain back to its source to determine where contamination occurred, while advising anyone with prolonged gastrointestinal symptoms after eating at the chain to consult a healthcare provider.