Last updated July 13, 2026
By: Claire Rifkin, MS, RDN, LDN
If you have recently seen headlines about an intestinal parasite infection causing prolonged diarrhea, they are likely referring to cyclosporiasis. The illness is caused by a microscopic parasite called Cyclospora cayetanensis, commonly shortened to Cyclospora.
As of July 9, 2026, the Centers for Disease Control and Prevention had received reports of 843 domestically acquired cases across 31 states. Eighty-six people had been hospitalized, and no deaths had been reported. The CDC expects case counts to keep rising because the federal data carry an estimated six-week reporting lag.
Some state numbers are already much higher. Michigan reported 2,640 cases as of July 13, illustrating how quickly this outbreak is developing and how much more current state reporting may be than the national count.
Investigators have not identified one food, brand or supplier responsible for all of these illnesses. The Food and Drug Administration is conducting traceback investigations into several Cyclospora clusters, but the products connected to the active investigations have not been publicly identified.
Here is what we currently know about cyclosporiasis, the symptoms to watch for and how to approach fresh produce without panicking or eliminating nutritious foods unnecessarily.
What Is Cyclosporiasis?
Cyclosporiasis is an intestinal illness caused by the parasite Cyclospora cayetanensis. People become infected after consuming food or water contaminated with the parasite. Cyclospora infects the small intestine and commonly causes frequent, watery diarrhea.
The illness is generally not spread directly from one person to another. After Cyclospora leaves the body in stool, it must spend at least one to two weeks in the environment before it becomes infectious. This makes immediate person-to-person transmission unlikely.
What Are the Symptoms of Cyclosporiasis?
Watery diarrhea is the most common symptom of a Cyclospora infection. The bowel movements may be frequent and, in some cases, sudden or explosive.
Other possible symptoms include:
- Loss of appetite
- Unintentional weight loss
- Stomach cramps
- Bloating or increased gas
- Nausea
- Fatigue
Vomiting, headaches, body aches and a low-grade fever are less common but can occur. Symptoms usually begin about one week after exposure, although they may appear anywhere from two days to two weeks or longer after consuming contaminated food or water.
Without treatment, cyclosporiasis may last for several weeks. Symptoms can also improve temporarily and then return. That pattern can make the infection feel different from a brief stomach bug or a single episode of food poisoning.
What Foods Are Linked to Cyclospora?
Fresh produce has been connected to previous Cyclospora outbreaks in the United States. Foods implicated in past outbreaks include raspberries, basil, cilantro, snow peas, salad mixes and certain types of lettuce.
That does not mean those foods are responsible for the current outbreak. As of July 13, the FDA had not publicly identified the products involved in its active Cyclospora investigations. Avoid assuming a specific fruit, vegetable, restaurant or brand caused an illness unless public health officials have announced a confirmed connection.
Michigan has issued more cautious recommendations because of the size of its local outbreak. Restaurants and commercial kitchens in Southeast Michigan have been advised to purchase whole heads of lettuce instead of bagged salad mixes, remove the outer leaves and wash the remaining leaves under running water. The state also recommends cooking produce when practical and heating it to at least 158°F. These are regional recommendations and should not automatically be interpreted as a nationwide advisory to avoid bagged salads.
Do You Need to Stop Eating Fresh Produce?
At this point, I would not recommend eliminating all fresh fruits and vegetables unless federal, state or local public health officials tell you to avoid a specific product.
Fresh produce provides fiber, vitamins, minerals and plant compounds that support health. Removing it from your diet indefinitely would not eliminate every possible foodborne illness risk and could make it harder to meet your nutritional needs.
The more useful approach is to follow current outbreak notices, use sound food-handling practices and pay attention to any location-specific recommendations from your health department. Recommendations may differ in areas experiencing concentrated outbreaks.
People who are more vulnerable to dehydration or serious complications may decide to take additional precautions while investigations continue. This includes young children, older adults and people with weakened immune systems. Anyone unsure about their individual risk should speak with a health care provider.
Can Washing Produce Remove Cyclospora?
Washing produce remains an important food-safety practice, but it cannot guarantee that Cyclospora will be removed. The parasite can be difficult to wash away, particularly from foods with rough surfaces, tightly packed leaves or small crevices. Routine chemical sanitizers may not kill it either.
The CDC recommends washing fruits and vegetables thoroughly under running water before cutting, eating or cooking them. Firm produce, such as melons and cucumbers, can be scrubbed with a clean produce brush. Produce labeled “prewashed” does not need to be washed again at home.
Additional food-safety steps include:
- Washing your hands with soap and water before and after preparing produce
- Cutting away bruised or damaged areas
- Refrigerating cut or peeled produce within two hours
- Cleaning utensils, cutting boards and preparation surfaces
These steps lower the risk of several foodborne illnesses, even though they cannot remove every possible Cyclospora organism.
What Should You Do if You Develop Symptoms?
Contact a health care provider if you develop sudden or persistent watery diarrhea, particularly when it is accompanied by appetite loss, weight loss, fatigue or signs of dehydration.
Tell your provider about recent foods you ate, restaurants you visited and any travel. Receipts, grocery-shopping histories and restaurant orders may help public health officials investigate a possible outbreak connection.
It is also important to ask whether your stool sample is being tested specifically for Cyclospora. Testing for this parasite is not automatically included in every routine stool test or gastrointestinal PCR panel. Because the organism can be difficult to detect, some patients may need to submit samples collected on more than one day.
How Is Cyclosporiasis Treated?
The prescription antibiotic trimethoprim-sulfamethoxazole, also known as TMP-SMX, is the preferred treatment for cyclosporiasis. Most people with healthy immune systems will eventually recover without medication, but untreated illness may be prolonged or return after appearing to improve.
Treatment decisions should be made with a medical provider. This is especially important for people who are pregnant, breastfeeding, allergic to sulfa medications or managing other medical conditions. There is no over-the-counter medication that eliminates the parasite.
Replacing fluids is also important because frequent diarrhea can lead to dehydration. Seek prompt medical attention if you cannot keep fluids down, are urinating much less than usual, feel faint or are concerned about dehydration.
The Bottom Line
The current cyclosporiasis outbreak is still under investigation, and no single food has been identified as the nationwide source. Federal case numbers are expected to rise, while state health departments may have more current information about local outbreaks.
You do not need to panic or automatically stop eating all fresh produce. Wash produce under running water, store it safely and follow any advisories issued for your area. Because washing cannot guarantee Cyclospora removal, people in heavily affected areas or at greater risk of complications may choose cooked produce more often while investigations continue.
Persistent watery diarrhea should not be ignored. Contact your health care provider and ask whether specific Cyclospora testing is appropriate, particularly if symptoms last longer than a typical stomach illness or improve and then return.
This article is for educational purposes and is not a substitute for individual medical care. Outbreak information can change quickly, so review the latest CDC, FDA and local health department updates.
