Compiled By: Dr. Al B. Wagner, Jr.

Professor/Extension Food Technologist
Texas A&M University
Texas Cooperative Extension

June 20, 1996

Several newspapers over the last week have reported on outbreaks of the parasite cyclospora in fresh strawberries in Texas, Florida, Boston, New York City and Ontario. The Texas Department of Health on June 7 advised consumers not to eat fresh strawberries, but did not instruct grocers to pull them off grocery shelves.

The parasite causes diarrhea, fatigue, loss of appetite, abdominal cramps and low-grade fever within one to fourteen days after consumption. The source of contamination in not yet known.

Outbreaks are also suspected in Ohio, Pennsylvania and Illinois.

The following information was received from the Science Communication group at the Institute of Food Technologists. It is a fact sheet prepared by the Center for Disease Control (CDC) in Atlanta.

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 cases of Cyclospora infection were diagnosed in 1977. Cases began being reported more often in the mid-1980's. This may be in part because better techniques are now being used to detect the parasite in stool samples. 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. We do not know how commonly it is spread. Cyclospora needs time (days or weeks) after being passed in a bowel movement to develop into an infectious organism. Cyclospora can be spread if stool from an infected person contaminates water or food, and someone accidentally drinks or eats that water or food. 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.

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 such as Cryptosporidium 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 feces. Persons who have previously been infected with Cyclospora can become infected again.

Has Cyclospora Been Found On Strawberries?

No, the Cyclospora parasite has not been found on strawberries.

Then why have strawberries been implicated? Based on food history interviews, strawberries were a common food eaten by the infected persons.

Can The Organism Be Killed By Cooking If I Want To Make Jelly?

Yes, boiling will kill the parasite.

What About Freezing?

The general consensus is that freezing will inactivate the organism.

Can Cyclospora Get Inside The Berry?

Only if the berry is cut or wounded. It cannot be taken up into the plant through soil.

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