Investigation Into Cyclosporiasis Cases Expands Across 31 States

OAKLAND, Calif. – Public health officials are now looking into potential cases of cyclosporiasis, a parasite linked to severe digestive issues, in at least 31 states, including California. The Centers for Disease Control and Prevention (CDC) issued a report on Friday as the outbreak continues to grow nationwide.

CDC Reports on Current Situation

Since May 1, 2026, the CDC has identified 843 confirmed cases of cyclosporiasis and is aware of over 1,500 additional cases that require further investigation to determine if they are domestically acquired. The numbers reported by state and local health authorities, however, might be higher than what the CDC reflects.

The CDC revealed that individuals who fell ill did not travel outside the U.S. within the 14 days before becoming sick. While 86 hospitalizations have been noted, no deaths linked to the outbreak have been reported so far.

California’s Case Count

What we know:

Reports indicate that cases of cyclosporiasis have emerged in 31 states since May 1. In California, the CDC reports one to ten cases. Additionally, various states have observed a rise in cases over the last two weeks compared to the same period in 2025.

As of July 10, Michigan has registered 1,562 cases, with 44 individuals hospitalized. It’s recognized as one of the hardest-hit areas amidst the ongoing outbreak, prompting a collaborative investigation between state and federal partners to identify the source of these illnesses.

Understanding Cyclosporiasis

According to the CDC, cyclosporiasis is a gastrointestinal illness caused by the parasite Cyclospora, typically found in developing nations. It spreads through food or water contaminated with feces and is not transmitted directly between people.

Symptoms can manifest as watery diarrhea, appetite loss, and weight loss. Without treatment, the illness can last anywhere from a few days to over a month, and symptoms might return intermittently.

At this moment, officials have not traced the recent outbreak to any specific food source, though the Michigan health department has noted produce types associated with previous outbreaks, including:

• Bagged salad mixes
• Fresh cilantro
• Fresh basil
• Raspberries
• Snow peas
• Green onions (scallions)

Preventative Measures

To minimize the risk of infection, health officials recommend rinsing produce with running water and thoroughly rubbing the surface. While frozen options may be safer than fresh, cooking food is the most reliable method for prevention.