What is cyclosporiasis, the parasitic illness causing ‘explosive’ diarrhea?

Cyclospora cayetanensis, the parasite that causes the illness. Ohio and Michigan have reported sharp increases in cases. Photograph: CDC View image in fullscreen Cyclospora cayetanensis, the parasite that causes the illness. Ohio and Michigan have reported sharp increases in cases. Photograph: CDC Explainer What is cyclosporiasis, the parasitic illness causing ‘explosive’ diarrhea? Illness surging in Michigan and other US states is rarely life-threatening, CDC says – but it can have severe effects CDC investigates parasite that’s caused cases of ‘explosive’ diarrhea in 18 US states Cases of cyclosporiasis – a parasitic illness that can cause “explosive”, watery diarrhea – have surged across the United States in recent days, health officials have said, with an abnormally large outbreak of almost 1,000 cases reported in Michigan . Michigan typically reports about 50 cases a year, making the current outbreak the largest in the state’s history and one of the nation’s biggest in recent years. Ohio has also reported a sharp increase, with 177 cases as of 2 July, since the CDC’s last count. The US Centers for Disease Control and Prevention (CDC) has recorded 145 cases across 17 states, as of 16 June, with some hospitalizations, but the agency’s data lags significantly behind state reporting and is probably a substantial undercount. Late Thursday, the CDC identified lettuce from Mexico served by Taco Bell locations across five US states as a source of the widespread outbreak. They’ve warned consumers not to eat shredded iceberg lettuce from Taco Bell restaurants in Indiana, Kentucky, Michigan, Ohio and West Virginia. A US Food and Drug Administration (FDA) investigation identified a single supplier of the lettuce. The federal warnings to consumers did not identify the company. “FDA is working with the supplier of iceberg lettuce to determine if potentially contaminated shredded iceberg lettuce remains on the market,” including in other states, the CDC said. “Taco Bell has committed to stop using any lettuce from the supplier identified by FDA’s traceback investigation.” Cyclosporiasis is rarely life-threatening, and no deaths have been linked to the current outbreak. Here’s what you need to know. What is cyclosporiasis? The gastrointestinal illness is caused by the parasite cyclospora, which spreads through raw produce and water that has been contaminated with human feces. In the US, it is a seasonal illness, with outbreaks tending to occur most often during the summer months between May and August. Past outbreaks have been linked to contaminated raw fruit, vegetables and herbs such as basil, cilantro, berries and spinach. The most commonly reported symptom is watery diarrhea “with frequent and sometimes explosive bowel movements”, according to the CDC. Often the diarrhea may resolve and then return. Other symptoms include cramps, nausea, fatigue, loss of appetite, low-grade fever and vomiting. Symptoms can last anywhere from several days to over a month