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What is Cyclospora?

Cyclospora (Cyclospora cayetanensis) is a parasite that is composed of only one cell. It is too small to be seen with the naked eye (only 8-10 microns in diameter). It used to be called by such names as cyanobacterium-like, coccidia-like, and Cyclospora-like bodies (CLBs).

The first known cases of Cyclospora infection were diagnosed in 1977 (reported in the medical literature in 1979). Cases have been reported with increased frequency since the mid-1980's, in part because of the availability of better techniques for detecting the parasite in samples of stool. Many questions remain about this tiny organism.

How is Cyclospora transmitted?

Cyclospora is transmitted by a person putting something in his/her mouth that was contaminated with infected stool. The parasite can be transmitted by swallowing contaminated water or food.

Who is at risk for infection?

Persons of all ages are at risk for infection. Although travelers to tropical countries may be at increased risk, infection can be acquired in such countries as the United States and Canada. The risk may vary with season; some evidence suggests that infection is most common in spring and summer.

What are the symptoms of infection?

Cyclospora infects the small intestine and typically causes an illness characterized by watery diarrhea, with an average of about 6 to 7 stools per day. Other symptoms can include loss of appetite, bloating, low grade fever, increased flatus (gas), stomach cramps, vomiting, tiredness, muscle aches, and weight loss. Other infectious organisms can cause illness that is very similar to that caused by Cyclospora. Some persons infected with Cyclospora do not develop any symptoms.

How soon after infection do symptoms appear?

Symptoms appear several days to a week after exposure (average 7 days).

What is the treatment for Cyclospora?

If not treated, the illness may last for a few days to a month or longer and may come back one or more times. Treatment with trimethoprim-sulfamethoxazole is recommended. Infected persons with diarrhea should rest and drink plenty of fluids.

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

If you think you may be infected with Cyclospora, you should consult your physician. Identification of this parasite in stool requires special kinds of laboratory techniques that are not routinely used. Therefore, your physician should specifically request testing for this parasite. More than one stool sample may need to be checked to find the organism. Your physician may also want to have your stool checked for other infectious organisms that can cause similar symptoms.

How do I avoid getting Cyclospora?

Avoiding water and food that may be contaminated with stool probably is the best way to prevent infection. Infected persons should wash their hands often to prevent the spread of infection. Persons who have previously been infected with Cyclospora can become infected again.

Where can I get more information?

UTAH DEPARTMENT OF HEALTH
BUREAU OF EPIDEMIOLOGY
August 2001