Since May 1, 2026, the Centers for Disease Control and Prevention (CDC) has received reports of 1,645 confirmed cases of cyclosporiasis in the United States and is aware of an additional 5,100 possible cases. These numbers are substantially higher than the 249 cases reported by this same time last year.
Because cyclosporiasis is often underdiagnosed and underreported, the true number of cases is likely higher than what has been reported to CDC.
CDC, the U.S. Food and Drug Administration (FDA), and state and local health departments are working together to investigate this multistate outbreak and identify the source(s).
What is cyclosporiasis?
Cyclosporiasis is an intestinal illness, affecting the stomach and gut, caused by a tiny parasite Cyclospora cayetanensis. People become infected after eating food or drinking water contaminated with the parasite. It commonly lives on fresh fruits or vegetables, and less commonly in water. The illness does not spread directly from person to person.
Symptoms typically begin about one week after exposure, although they can start as soon as two days or as late as two weeks afterward. The most common symptom is frequent, watery diarrhea, but people may also experience:
- Loss of appetite
- Weight loss
- Stomach cramps
- Bloating and increased gas
- Nausea
- Fatigue
- Less commonly, vomiting, headache, body aches, or a low-grade fever
As a result of diarrhea, the most frequent complications are severe dehydration and electrolyte imbalance. Without treatment, symptoms can last several days to more than a month and may improve before returning again. Although the illness can be severe, it is not usually life-threatening.
Where is the outbreak taking place?
As of July 14, the Centers for Disease Control and Prevention (CDC) has received reports of 1,645 confirmed cases of cyclosporiasis in the United States and is aware of an additional 5,100 possible cases. These numbers are substantially higher than the 249 cases reported by this same time last year. Cases have been reported in 34 states, with the largest number of case counts in Michigan. At this time:
- No single food item has been confirmed as the source of the outbreak.
- Investigators are interviewing people who became sick and tracing the foods they ate before becoming ill.
- The outbreak investigation is ongoing, and recommendations may change as more information becomes available.
How does cyclosporiasis spread?
Cyclosporiasis is caused by a tiny parasite, only visible under a microscope. It can spread in two ways:
- Contaminated foods: Consuming fresh (uncooked) produce is the most common source of outbreaks in the United States and believed to be the cause of the current outbreak.
- Contaminated water: This may include drinking untreated water or accidentally swallowing untreated swimming water (for example, water in swimming pools, hot tubs or lakes) that has been contaminated with the parasite.
Fruits and vegetables tied to past cyclosporiasis outbreaks in the U.S. include: basil, bagged salads and salad mixes, cilantro, mesclun lettuce, parsley, raspberries, snow peas, and sweet peas.
How do I prevent cyclosporiasis?
While the source of the current outbreak has not been identified, you can help reduce your risk by:
- Cooking fresh fruits and vegetables to at least 158 degrees Fahrenheit
- Thoroughly washing or peeling fresh fruits and veggies before eating them, even if your produce is labeled as “pre-washed”
- Practicing safe food handling and food safety guidelines
It’s important to know that chemical disinfectants or sanitizers are unlikely to kill the parasite that causes cyclosporiasis.
Is there a treatment for cycloporiasis?
Yes. Once a lab test has confirmed you have cycloporiasis, there are treatment options. This usually includes an antibiotic that will kill the parasite that causes the infection. Your healthcare provider might also prescribe anti-diarrheal medication and recommend staying hydrated.
The infection can sometimes go away on its own, but symptoms can last up for a month if left untreated. Children, older adults, and people with weakened immune systems may also be at higher risk of severe infection.
Should I stop eating fresh fruits and vegetables?
No. CDC has not advised people to stop eating fresh fruits and vegetables.
Fresh produce is an important part of a healthy diet. Because investigators have not identified a source of the outbreak, you can continue eating produce while following prevention and food safety guidelines.
What should I do if I think I have cyclosporiasis?
If you develop symptoms of cyclosporiasis—especially prolonged or watery diarrhea—contact your healthcare provider. Your provider may:
- Order a test to check for the parasite.
- Prescribe an antibiotic if appropriate.
- Recommend drinking plenty of fluids to prevent dehydration.
If you have severe diarrhea, signs of dehydration, or symptoms of cyclosporiasis that persist or worsen, it is important to seek medical attention.
