Parasite causing major stomach symptoms - KTVU

At least 31 states, now including California, are investigating potential cases of cyclosporiasis, the parasite known to cause "explosive diarrhea."The Centers for Disease Control and Prevention (CDC) released an update on Friday as the parasite continues to spread across the U.S.Since May 1, 2026, the CDC said it has received reports of 843 confirmed domestic cases of cyclosporiasis and is aware of more than 1,500 cases that require further analysis to confirm the illness as domestically acquired cyclosporiasis, according to Friday’s update.However, state and local health officials have reported much higher numbers. The CDC noted that it is aware that states are likely to report higher case counts of cyclosporiasis than reflected in CDC data and said it is working closely with states to update numbers as additional cases are confirmed. According to the agency, those who contracted the illness became sick after eating food in the United States and did not report any travel during the 14 days before they got sick.The CDC reported that 86 people have been hospitalized due to cyclosporiasis, but no deaths have been reported.Since May 1, cases of cyclosporiasis have been reported across 31 states.The CDC reports one to 10 cases in California.So far this year, multiple states have reported an increase in cases in the last two weeks compared to the same period in 2025.According to the Michigan Department of Health and Human Services, there have been 1,562 total cases in Michigan and 44 reported cases hospitalized as of Friday, July 10.Michigan continues to be one of the hardest-hit states in the ongoing cyclosporiasis outbreak.The CDC said state and federal partners are working together to investigate several outbreaks of cyclosporiasis. Investigations to identify the source or sources of illness are ongoing.According to the CDC, cyclosporiasis is a gastrointestinal disease caused by the microscopic parasite Cyclospora.Experts say it’s usually found in developing countries and is spread by food or water contaminated with feces. It doesn’t spread from person-to-person. Symptoms of cyclosporiasis can include watery diarrhea, loss of appetite and weight loss.For people who do not get treatment, health experts say the illness may last for a few days to over a month. Symptoms could go away and then return one or more times.Public health officials haven’t linked the most recent outbreak to a specific type of produce grower or supplies, or a specific type of produce as a potential source of the outbreak.However, the Michigan Department of Health and Human Services released a list of produce that has been tied to previous outbreaks, including: Health officials say rinsing produce with running water and rubbing the surface of the fruit or vegetable can help to prevent the illness. They also say to consider frozen over fresh, although that doesn’t completely eliminate the risk. It’s safest if it’s cooked.