The US Centers for Disease Control and Prevention (CDC) is investigating a surge in cyclosporiasis cases, a parasitic illness causing watery and sometimes explosive diarrhea. Michigan has reported nearly 1,000 cases, its largest outbreak ever, while Ohio has 177 cases as of July 2. The CDC has recorded 145 cases across 17 states as of June 16, but state data suggests a significant undercount.
Source Identified: Taco Bell Lettuce from Mexico
Late Thursday, the CDC identified shredded iceberg lettuce from Mexico served at Taco Bell locations in Indiana, Kentucky, Michigan, Ohio, and West Virginia as a source. The FDA traced the lettuce to a single supplier, though the company was not named. Taco Bell has stopped using lettuce from that supplier. The CDC warns that potentially contaminated lettuce may still be on the market in other states.
What Is Cyclosporiasis?
Cyclosporiasis is caused by the parasite Cyclospora cayetanensis, which spreads through raw produce or water contaminated with human feces. In the US, outbreaks typically occur from May to August. Past outbreaks have been linked to basil, cilantro, berries, and spinach. Symptoms include watery diarrhea with frequent, explosive bowel movements, cramps, nausea, fatigue, loss of appetite, low-grade fever, and vomiting. Symptoms can last days to over a month. The incubation period averages one week but can range from two days to two weeks. The illness is rarely life-threatening, and most recover without treatment, though antibiotics are used for severe cases.
Comparison to Previous Outbreaks
While comprehensive data is limited, only a few outbreaks have exceeded 1,000 cases in the last 20 years. In 1996, Guatemalan raspberries sickened nearly 1,500 people. In 2019, Mexican basil caused over 2,400 cases across the US and Canada. The current Michigan outbreak is one of the largest in recent years.
Protection Measures
The CDC recommends thoroughly washing fresh produce, though Cyclospora can cling to crevices in foods like raspberries, lettuce, and basil. Consumers are advised to buy whole heads of lettuce, remove outer leaves, and wash under running water. Cooking produce can kill the parasite. No deaths have been reported in the current outbreak.
