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Bureau of Disease Control


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 illness caused by Cyclospora infection were reported in 1979. Cases began being reported more often in the mid-1980s. In the last several years, outbreaks of cyclosporiasis have been reported in the United States and Canada.

What are the symptoms?

Cyclospora usually causes watery diarrhea, with frequent, sometimes explosive, bowel movements. Other symptoms can include loss of appetite, loss of weight, bloating, increased gas, stomach cramps, nausea, vomiting, muscle aches, lowgrade fever, and fatigue. The time between becoming infected and becoming sick is usually about 1 week. 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). Some people who are infected with Cyclospora do not have any symptoms.

How is Cyclospora treated?

The recommended treatment for infection with Cyclospora is a combination of two antibiotics. See your doctor for other treatment recommendations. People who have diarrhea should rest and drink plenty of fluids.

How do people catch this disease?

Cyclospora is spread by people drinking water or eating food that was contaminated with infected stool. For example, outbreaks of cyclosporiasis have been linked to various types of fresh produce. 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 not known if animals can be infected and spread infection to people.

What can be done to stop the spread of this disease?

Wash your hands before and after handling food. Wash all fruits and vegetables before eating. Avoid water or food that may be contaminated with stool.