Cyclosporiasis is an illness you can get if you eat food contaminated with a parasite called Cyclospora cayetanensis.
Cyclospora can infect your small intestine and cause days or even weeks of digestive symptoms like watery or explosive diarrhea. It’s often found on fresh, raw produce.
It’s not a new illness. People first started reporting cyclosporiasis cases back in 1979, and there have been a number of outbreaks in the United States since then. In early May 2026, the CDC began getting reports of an increasing number of cyclosporiasis cases in Michigan. As of mid-July 2026, the CDC had confirmed more than 1,600 cases and 140 hospitalizations across 34 states.
The symptoms of cyclosporiasis can be unsettling, but the condition is rarely life-threatening. There are treatments for it, or it may just go away on its own.
“For the vast majority of people, this is going to be just an annoyance,” says Linda Yancey, MD, an infectious disease specialist at Memorial Hermann Health System in Houston. “It will make you miserable for a few days, but we haven’t had any deaths reported and – knock on wood – hopefully we won’t.”
Here are the facts about cyclosporiasis, including how to protect yourself from it.
Causes
When you eat food or drink water contaminated with cyclospora, it enters your digestive tract and infects your intestines. Food can get cyclospora on it when it comes into contact with human feces (poop) during growing, harvesting, processing, or preparation.
“Maybe someone doesn’t wash their hands as much as they should, and then they come into contact with some kind of food, and that gets it into the food supply,” says Yancey. “And if that food isn’t cooked, if it’s consumed raw, then you can pass along the case of cyclospora to the next host.”
One reason outbreaks can last is because people who get cyclosporiasis don’t show symptoms right away. After you’re exposed to cyclospora, it generally takes 10 days to have symptoms, which makes it harder to figure out which food caused your illness, she says.
“You might be able to list the meals you had yesterday, but try to think about everything you ate 10 days ago,” Yancey says. “It’s really difficult.”
Cyclosporiasis Symptoms
The main symptom of cyclosporiasis is frequent watery and explosive diarrhea. Other symptoms can include:
- Nausea
- Vomiting
- Stomach cramps
- Bloating
- Loss of appetite
- Fatigue
- Weight loss
- Gas
Yancey says you can tell cyclosporiasis from a simple case of an upset stomach in two key ways: bloating and the length of time you have symptoms. Cyclosporiasis lasts much longer than a typical stomach bug.
“Worst-case scenario, this can last for several weeks,” she says. “And the one thing that cyclospora tends to do more than other diarrheal illnesses is cause a lot of bloating. It can be pretty miserable.”
Cyclosporiasis Treatment
Your doctor may suggest over-the-counter medications that contain loperamide (Imodium). This medication is not recommended for children, so if your child is sick, talk to your doctor about what medications may be right for them. This will help you feel better, but it isn’t a cure for cyclosporiasis.
Your doctor will also recommend oral hydration to help manage diarrhea so that you don’t get dehydrated and lose important nutrients. A bland diet, such as one called BRAT (bananas, rice, applesauce, and toast), will help soothe your stomach short-term.
If you’re still having symptoms after five days, Yancey says, call your primary care provider and get an appointment. Your doctor can take a special stool sample to tell if you have cyclosporiasis. To treat it, they’ll prescribe an antibiotic called trimethoprim-sulfamethoxazole (Bactrim, Septra). It’s a pill you take twice a day for a week. You should have fewer symptoms within a few days of starting treatment.
While you’re having cyclosporiasis symptoms, stay hydrated with fluids such as water and sports drinks that contain electrolytes.
Who’s at Risk?
Anyone can get cyclosporiasis, but some people are at a higher risk of severe symptoms or complications, including:
- Adults ages 65 and older
- Young children
- People with weakened immune systems
- People receiving chemotherapy
- Organ transplant recipients
- People with certain immune disorders
“The very old and the very young are going to be at risk of dehydration from the diarrhea,” says Yancey. “And also, this can be very bad in people who have weakened immune systems. It’s one of the reasons that when you’re on certain chemotherapy regimens, they will tell you not to consume fresh fruits and vegetables. It’s specifically to avoid cyclospora.”
Most healthy adults recover fully from cyclosporiasis, but serious dehydration is a risk any time you have multiple days of diarrhea. Drink plenty of fluids and seek medical care to help prevent complications.
Common Food Sources of Cyclospora
Typically, foods to watch out for are raw fruits and vegetables, especially those with textured surfaces that are hard to clean.
“It’s destroyed by cooking, which is why everybody’s talking about fresh fruits and vegetables,” Yancey says. “You can get cyclospora from a bowl of fresh raspberries, but if you bake them up into raspberry tarts, you’re perfectly safe.”
Foods that have been linked to past cyclospora outbreaks include:
- Cilantro
- Lettuce
- Mixed salad greens
- Basil
- Raspberries
- Blackberries
- Snow peas
Prevention
You can lower your risk of cyclosporiasis by following safe food-handling habits. Be sure to:
- Wash your hands before and after handling food.
- Rinse fruits and vegetables under running water.
- Scrub firm produce such as cucumbers and melons with a clean scrub brush.
- Refrigerate produce right after you cut it.
Avoiding all fresh fruits and vegetables isn’t realistic – or healthy, says Yancey. To be on the safe side, she recommends sticking to options with smooth surfaces you can really scrub well.
“Cyclospora is not terribly sticky – you can absolutely dislodge it with water, but not if it has nooks and crannies to hide in,” she says. “This might be a time to have a cucumber salad instead of a lettuce salad. And grapes and blueberries that are nice and smooth and easy to wash off are going to be better for you than the raspberries and blackberries that are difficult to clean.”
Outlook
You’re very likely to have a complete recovery from cyclosporiasis, especially if you get treatment. Death is extremely rare from the parasite infection, and the CDC hasn’t reported any deaths from the current outbreak. Yancey expects health officials to eventually find the source and bring the outbreak under control.
“They will take all of the suspect produce off the market, and this will end the way all the other cyclospora outbreaks have ended – it will sputter out,” she says.
If you have diarrhea that lasts longer than a few days, especially if it comes with bloating, nausea, or fatigue, see your doctor. You’re more likely to feel better sooner, and reporting your case helps public health measures, says Yancey.
“It gives the CDC a picture of what’s actually going on out there,” she says.
Takeaways
- Cyclosporiasis is a parasitic illness spread through food contaminated with human feces, usually via unwashed raw produce.
- It causes prolonged watery diarrhea, bloating, and fatigue that lasts days to weeks.
- The illness is rarely serious but can hit high-risk groups – older adults, young children, and people with weakened immune systems – harder. Dehydration is the main danger.
- Treatment involves hydration, a bland diet, and, if symptoms last more than five days, a course of antibiotics.
- You can lower your risk of cyclosporiasis by following safe food-handling habits, including washing your hands and all raw produce thoroughly. For eating raw, choose smooth-skinned foods like cucumbers and grapes over those with textured rinds or peels.
Cyclosporiasis FAQs
How do you get cyclosporiasis?
You can get cyclosporiasis if you eat food or drink fluids contaminated with the parasite Cyclospora cayetanensis.
Is cyclosporiasis contagious?
You can’t catch cyclosporiasis from contact with another person. You have to eat or drink something infected with the cyclospora parasite.
How long does a cyclosporiasis infection last?
Symptoms usually start within a week after you’ve been infected with the parasite. If untreated, they can last weeks and even months. They can go away and then come back.
Can cyclosporiasis be prevented?
You can lower your risk of getting the condition by handling food safely: Wash your hands before and after handling produce, wash all produce with running water, and sanitize cutting boards and countertops after food prep. Don’t swim or bathe in water that may be contaminated, such as lakes and public hot tubs.
What common food sources can cause cyclosporiasis?
Foods that have most often been linked to past outbreaks include lettuce and mixed salad greens, raspberries, blackberries, snow peas, cilantro, and basil.
Will cyclosporiasis clear up on its own?
If you have a healthy immune system, cyclosporiasis will eventually go away on its own. But this can take anywhere from several days to several weeks, and symptoms can come back. If you think you may have it, see your doctor within a few days for treatment. If you have a weakened immune system, see your doctor as soon as possible.
