July 22 - The U.S. Food and Drug Administration has announced an investigation into a fresh outbreak of cyclosporiasis, with 72 reported illnesses connected to an as-yet-unidentified source. The agency said it has started a traceback to try to determine where the contaminated product originated.
Public-health authorities are already contending with an expanding cluster of cyclospora infections across the U.S. Midwest. The Centers for Disease Control and Prevention has recorded 4,173 laboratory-confirmed, domestically acquired cases of cyclosporiasis in the United States since May 1, and it is probing more than 7,400 additional reported infections that have not yet been laboratory confirmed. Many of those additional reports are concentrated in Michigan and Ohio.
Michigan has reported 7,171 cases so far this year, while Ohio has also registered a notable increase in infections. Regulators have linked the broader Midwest spread - described by authorities as the largest foodborne illness outbreak in the U.S. in recent years - to a Taylor Farms processing plant in Mexico.
On July 17, Taylor Farms issued a recall for iceberg lettuce sourced from central Mexico. The recall covers lettuce sold at retail, served in restaurants, and distributed to food service customers. Mexican authorities, however, said on Tuesday there was not yet evidence to indicate that lettuce originating from Mexico caused the U.S. outbreak.
Cyclospora is an intestinal illness caused by the Cyclospora parasite. Infection typically follows ingestion of contaminated food or water. Symptom profiles can include:
- Diarrhea
- Stomach cramps
- Nausea
- Fatigue
The outbreak has had commercial consequences as well as public-health ones. Restaurant operators have been affected: shares of Yum Brands dropped nearly 10% last week after reports connected Taco Bell to the spread of the illness. Analysts cited by reports suggested that any sales effects at the chain were unlikely to be long lasting. Taco Bell has stopped using lettuce supplied by Taylor Farms.
Public-health officials note that cyclospora infections often rise in the United States during the spring and summer months, when warmer conditions favor the parasite and can prompt multistate investigations by health authorities. The FDA's ongoing traceback and the CDC's laboratory confirmations will determine how the new cluster of 72 cases relates to the wider set of infections under investigation.