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Cyclospora

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What is Cyclospora?

Cyclosporiasis is an intestinal illness caused by the microscopic parasite Cyclospora cayetanensis. 

Cyclospora cayetanensis is a parasite composed of one cell, too small to be seen without a microscope.

People become infected by consuming food or water contaminated with the Cyclospora parasite.

the time between becoming infected with cyclospora
and becoming sick is usually about 1 week

How is cyclospora spread?

Cyclospora is spread by people ingesting something – such as food or water – that was contaminated with feces (poop). 

Cyclospora needs time (days to weeks) after being passed in a bowel movement to become infectious for another person. Therefore, it is unlikely that Cyclospora is passed directly from one person to another.

Who is at risk for Infection?

In the United States, foodborne outbreaks of cyclosporiasis have been linked to various types of imported fresh produce. 

People living or traveling in countries where cyclosporiasis is endemic may be at increased risk for infection.

What are the most common symptoms?

Cyclospora infects the small intestine (bowel) and usually causes:

  • Watery diarrhea, with frequent, sometimes explosive, bowel movements
  • Loss of appetite
  • Weight loss
  • Stomach cramping/pain
  • Bloating
  • Increased gas
  • Nausea
  • Fatigue

Less common symptoms include:

  • Vomiting
  • Body aches
  • Headaches
  • Low-grade fever
  • Other flu-like symptoms


The time between becoming infected and becoming sick is usually about 1 week.  Some people who are infected with Cyclospora do not have any symptoms.

How long can symptoms last?

If not treated, the illness may last from a few days to a month or longer. Symptoms may seem to go away and then return one or more times (relapse).

It’s common to feel very tired. If you think you’ve been infected with Cyclospora see your healthcare provider.

Diagnosing a cyclospora infection

Your health care provider will ask you to submit stool specimens to see if you are infected.

You might be asked to submit more than one specimen from different days.

Identification of this parasite in stool requires special laboratory tests that are not routinely done.

Therefore, if indicated, your health care provider should specifically request testing for Cyclospora.

In addition, your health care provider might have your stool checked for other organisms that can cause similar symptoms.

CDC/ DPDx – Melanie Moser

Treatment for Cyclosporiasis

In the US, since the mid-1990s, outbreaks of cyclosporiasis have been linked to imported fresh produce like raspberries.

Recommended Treatment

The recommended treatment is a combination of two antibiotics, trimethoprim-sulfamethoxazole, also known as Bactrim*, Septra*, or Cotrim*. People who have diarrhea should also rest and drink plenty of fluids. If a person ill with cyclosporiasis is not treated, symptoms can persist for several weeks to a month or more.

Some symptoms, such as diarrhea, can return; and some symptoms, such as muscle aches and fatigue, may continue after the gastrointestinal symptoms have gone away. The infection usually is not life threatening.

In the US, since the mid-1990s, outbreaks of cyclosporiasis have been linked to imported fresh produce like mesclun lettuce.

Is there another drug available?

I am allergic to sulfa drugs; is there another drug I can take?

No highly effective alternative drugs have been identified yet for people with Cyclospora infection who are unable to take sulfa drugs. See your health care provider to discuss potential options.

In the US, since the mid-1990s, outbreaks of cyclosporiasis have been linked to imported fresh produce like snow peas.

Prevention

Avoiding food or water that might have been contaminated with stool may help prevent Cyclospora infection.

People who have previously been infected with Cyclospora can become infected again. In the United States, foodborne outbreaks of cyclosporiasis since the mid-1990s have been linked to various types of imported fresh produce, including raspberries, basil, snow peas, and mesclun lettuce; no commercially frozen or canned produce has been implicated.

In the US, since the mid-1990s, outbreaks of cyclosporiasis have been linked to imported fresh produce like basil.

Currently Available Information

On the basis of the currently available information, avoiding food or water that may have been contaminated with feces is the best way to prevent cyclosporiasis.

Treatment with chlorine or iodine is unlikely to kill Cyclospora oocysts. No vaccine for cyclosporiasis is available. CDC monitors the occurrence of cyclosporiasis in the United States and helps state health departments identify and investigate cyclosporiasis outbreaks to prevent additional cases of illness.

Handling Recommendations

Consumers and retailers should always follow safe fruit and vegetable handling recommendations:

Wash: Wash hands with soap and warm water before and after handling or preparing fruits and vegetables. Wash cutting boards, dishes, utensils, and counter tops with soap and hot water between the preparation of raw meat, poultry, and seafood products and the preparation of fruits and vegetables that will not be cooked.

Prepare: Wash all fruits and vegetables thoroughly under running water before eating, cutting, or cooking. Fruits and vegetables that are labeled “prewashed” do not need to be washed again at home. Scrub firm fruits and vegetables, such as melons and cucumbers, with a clean produce brush. Cut away any damaged or bruised areas on fruits and vegetables before preparing and eating.

Store: Refrigerate cut, peeled, or cooked fruits and vegetables as soon as possible, or within 2 hours. Store fruits and vegetables away from raw meat, poultry, and seafood.
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