Berry Berry Quite Contrary...Cyclospora Outbreaks

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ATLANTA--Outbreaks of illness in the United States causing infectious watery diarrhea, nausea, and vomiting have been found to be related to a parasite called Cyclospora.

The Cyclospora parasite is transmitted to persons who contact objects contaminated with infected stool. In 1997, reports of outbreaks of Cyclospora infection were preliminarily associated with the consumption of fresh fruits, such as strawberries and raspberries.

The Center for Disease Control and Prevention (CDC) worked with the federal, state, and local health departments to determine the extent and causes of the recent outbreaks of Cyclospora. They pointed out that although it is prudent to thoroughly wash produce that will be eaten raw, this practice may not eliminate the risk of transmission of Cyclospora. Further, they recommend that health care providers consider Cyclospora infection in persons with prolonged diarrheal illness and specifically request laboratory testing for this parasite.

The CDC has provided the following information:

What is Cyclospora?
Cyclospora is a parasite that is composed of one cell. It is too small to be seen without a microscope. Its full name is Cyclospora cayetanensis.

The first known human cases of Cyclospora infection were diagnosed in 1977. Cases began being reported more often in the mid-1980s. This may be in part because better techniques are now being used to detect the parasite in specimens of stool (bowel movements). Because Cyclospora is a newly recognized infectious organism, many questions remain about the ways it is transmitted and the illness it causes.

How is Cyclospora transmitted?
Cyclospora is transmitted by a person putting something in his or her mouth that was contaminated with infected stool. For example, the parasite can be transmitted by swallowing contaminated water or food. Cyclospora needs time (days or weeks) after being passed in a bowel movement to develop into an infectious organism. Therefore, transmission of Cyclospora directly from an infected person to an uninfected person is unlikely.

Who is at risk for infection?
Persons of all ages are at risk for infection. In the past, Cyclospora infection was usually found in persons living or traveling in tropical countries. More and more, cases are being recognized in countries such as the United States and Canada. The risk may vary with season. Infection may be most common in spring and summer. However, we do not yet know how common Cyclospora infection is.

What are the symptoms of infection?
Cyclospora infects the small intestine (bowel) and usually causes watery diarrhea, with frequent bowel movements. Other symptoms include loss of appetite, weight loss, bloating, increased gas, stomach cramps, nausea, vomiting, tiredness, muscle aches, and low-grade fever. Other infectious organisms can cause similar illness. Some persons infected with Cyclospora do not develop any symptoms.

The time between becoming infected and developing symptoms is usually several days to a week. If not treated, the illness may last for a few days to a month or longer. It may also return one or more times.

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 laboratory tests that are not routinely used. Therefore, your physician should specifically request testing for Cyclospora. More than one stool sample may be needed. Your physician may also want to have your stool checked for other infectious organisms that can cause similar symptoms.

How is infection treated?
Infection with Cyclospora is treated with antibiotics. Trimethoprim- sulfamethoxazole, also known as Bactrim*, Septra*, or Cotrim* (a combination of two antibiotics), is recommended. Infected persons with diarrhea should rest and drink plenty of fluids. They should seek their physician's advice before taking medicine to slow their diarrhea.

How is infection prevented?
Cyclospora infection can be prevented by avoiding water or food that may be contaminated with stool. Persons who have previously been infected with Cyclospora can become infected again.

For more information about Cyclospora infection, refer to the following articles.

• Chiodini PL. A "new" parasite: human infection with Cyclospora cayetanensis. Trans R Soc Trop Med Hyg 1994;88;369-71.



• Hoge CW, et al. Placebo-controlled trial of co- trimoxazole for cyclospora infection among travellers and foreign residents in Nepal. Lancet 1995;345:691-3.



• Hoge CW, et al. Epidemiology of diarrhoeal illness associated with coccidian-like organisms among travellers and foreign residents in Nepal. Lancet 1993;341:1175-9.



• Huang P, et al. The first reported outbreak of diarrheal illness associated with Cyclospora in the United States. Ann Intern Med 1995;123:409-14.



• Ortega YR, et al. Cyclospora species - a new protozoan pathogen of humans. N Engl J Med 1993;328:1308-12.



• Pape JW, et al. Cyclospora infection in adults infected with HIV: clinical manifestations, treatment, and prophylaxis. Ann Intern Med 1994;121:654-7.



• Wurtz R. Cyclospora: a newly identified intestinal pathogen of humans. Clin Infect Dis 1994;18:620-3.