Cyclospora

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What is cyclospora?

Cyclospora cayetanensis (SIGH-clo-SPORE-uh KYE uh-tuh-NEN-sis) is a parasite composed of one cell too small to be seen without a microscope. The first known human cases of cyclospora infection were reported in 1979. Cases began being reported more often in the mid-1980’s.

How is cyclospora spread?

Cyclospora is spread by people ingesting/swallowing food or water that is contaminated with human faecal matter. For example, in 1996, a large outbreak of cyclospora infection in the United States and Canada was caused by imported raspberries. Many recent outbreaks have been associated with contaminated fresh fruit (raspberries and strawberries) or vegetables (lettuce and basil). Cyclospora needs time (days or weeks) after being passed in a bowel movement to become infectious. Therefore, it is unlikely that cyclospora is passed directly from one person to another. It is unknown whether animals can be infected and pass on the infection to people. Cyclospora is resistant to chlorine.

Who is at risk for infection?

People of all ages are at risk for infection. In the past, cyclospora infection was usually found in people who lived or travelled in developing countries, but people can be infected worldwide. In the United States, infection is more common during spring and summer.

What are the symptoms of infection?

Cyclospora infects the small intestine (bowel) and usually causes watery diarrhea with frequent and sometimes explosive bowel movements. Other symptoms can include loss of appetite, substantial loss of weight, bloating, increased gas, stomach cramps, nausea, vomiting, muscle aches, low-grade fever, and fatigue. Some people who are infected with cyclospora do not have any symptoms.

How soon after infection will symptoms begin?

The time between becoming infected and becoming sick is usually about 1 week.

How long will 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).

What should I do if I think I may be infected?

See your health care provider.

How is cyclospora infection diagnosed?

Identification of this parasite in stool requires special laboratory tests that are not routinely done. Therefore, your health care provider should specifically request testing for cyclospora.

How is infection treated?

It is usually treated with a seven day course of oral antibiotics (usually a sulpha derivative). Treatment is recommended for those who are positive in their stools because of potential for recurrence of symptoms.

People who have diarrhea should rest and drink plenty of fluids. They should seek their health care provider’s advice before taking medicine to slow their diarrhea.

I am allergic to sulfa drugs. Is there another drug I can take?

No alternative drugs have been identified yet for people who are sensitive to sulfa drugs.

How is the infection prevented?

Produce should be washed thoroughly before it is eaten and although this may not eliminate the risk, this practice may reduce severity of disease. Avoiding water or food that may be contaminated with stool may help prevent cyclospora infection. People who have previously been infected with cyclospora can become infected again. Avoid swallowing recreational water contaminated with cyclospora.

If you have any questions contact Public Health or your doctor.

 CDC, Atlanta