Several US states affected by "explosive diarrhea"

Americans in about 30 states have been infected by a microscopic parasite transmitted through food, which can cause "explosive diarrhea," US health officials announced.

The state of Michigan, in the Midwest, is currently the epicenter of this cyclosporiasis outbreak. Local authorities there had recorded 1,562 cases as of Friday, July 10.

The U.S. Centers for Disease Control and Prevention (CDC) reported that, as of Thursday, 31 states had reported cases of this gastrointestinal infection. Several dozen people have been hospitalized, but no deaths have been reported.

Health authorities have not yet identified the source of the contamination, which is generally linked to the consumption of fresh produce. Since symptoms often appear several days after infection, it is difficult to trace the exact source.

In the past, cyclosporiasis has been associated with bagged salad mixes, fresh coriander, fresh basil, raspberries, snow peas, and spring onions.

It is often a mild illness, but it can be prolonged and cause severe dehydration.

Without treatment, the illness can last for more than a month. According to public health authorities, it is usually mild and rarely life-threatening, but it can lead to severe dehydration.

Health officials in several states, including Michigan, recommend washing fruits and vegetables thoroughly before eating them, or better yet, cooking them, as a temperature above 70°C is sufficient to destroy the parasite.

Assessing the extent of the epidemic is complicated, not only because of the relatively long incubation period, but also because reporting practices vary from state to state.

Some states group confirmed and probable cases together in the same report, while others only inform the CDC once their investigations are complete.

Read also The standoff between the Trump administration and the main US health agency is intensifying.

Under Trump, reporting cases of Cyclospora became optional.

In addition, since July 2025, under the administration of Donald Trump, the Secretary of Health, Robert F. Kennedy Jr., has made the reporting of cases of cyclosporosis by States, as part of a reduction of the national network for active surveillance of foodborne diseases.

Prior to this date, a collaborative CDC program called FoodNet was responsible for assisting various regulatory bodies in monitoring eight foodborne pathogens, including the one responsible for cyclosporiasis. Cyclospora cayetanensis, a circular parasite identified in humans since 1977, very resistant in the environment and which passes through the filters of drinking water systems.

Other pathogens, Campylobacter, the listeria, there Shigellathe different Yersinia (including the one responsible for the plague), the Vibrio (one species of which is responsible for cholera) are also no longer monitored. Only salmonella and the escherichia coli Enterohemorrhagics are still present. At the same time, the Trump administration cut funding to federal health agencies and laid off 20,000 of the original 82,000 employees.

“ The CDC knows that several states are likely reporting more cases of cyclosporiasis than currently reflected in national data and is working closely with them to update the figures as new cases are confirmed. " the agency states on its website.

To date, the CDC officially reports 843 confirmed cases, but specifies that it is aware of approximately 1,500 additional cases that still need to be analyzed.

“ Since the beginning of the year, several states have reported, over the past two weeks, an increase in the number of cases compared to the same period in 2025. ", the CDC added.