Cyclosporiasis Fact Sheet

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Cyclospora is a parasite that causes diarrhea

Cyclospora infections (cyclosporiasis) in humans have been reported since 1979 and the number of cases reported each year has increased since the mid 1980s. Large outbreaks of cyclosporiasis have been reported since 1996. It is believed that most of these outbreaks were caused by Cyclospora contaminated raspberries which were imported from another country, but other contaminated foods are also thought to have caused some outbreaks of cyclosporiasis.

Transmission can occur by eating food or drinking water contaminated with feces that contain Cyclospora

Cyclospora needs time (days or weeks) to become infectious after being shed in feces (stool). Because Cyclospora takes so much time to become infectious, it is unlikely that Cyclospora is passed directly from one person to another. The primary source of the parasite is not yet known, and it is unknown whether animals can be infected and pass the infection to people.

Symptoms appear about 1 to 14 days (usually one week) after eating contaminated food or drinking contaminated water

Symptoms include watery diarrhea with frequent, sometimes explosive, bowel movements. Other symptoms can include extreme fatigue, loss of appetite, substantial weight loss, increased gas and bloating, stomach cramps, nausea, vomiting, and low-grade fever. Symptoms of cyclosporiasis may come and go and, if untreated, illness can last for a few days to a month or longer. Some infected persons may not have symptoms.

Anybody can get cyclosporiasis

People of any age are at risk for infection. People living in or traveling to developing countries may be at increased risk, but infection can be acquired worldwide. In the United States, most cases of Cyclospora infection are detected in the spring and summer.

Cyclosporiasis is treated with antibiotics

Patients with AIDS may need longer treatments with higher doses of antibiotics. People with severe or long-lasting diarrhea should call their doctor.

Laboratory tests are available to look for Cyclospora in stool

Because many laboratories do not routinely check for Cyclospora in stool samples, your doctor must specifically request a Cyclospora test if cyclosporiasis is suspected.

The risk of cyclosporiasis can be reduced

Because the source of Cyclospora is not yet known, it is not possible to completely remove all risk of getting cyclosporiasis. Doctors, scientists, and public health specialists are still working to better understand Cyclospora. In the meantime, the following steps may help reduce the risk of getting cyclosporiasis and other diarrheal illnesses:

  • Wash fruits and vegetables before eating them.
  • Avoid drinking untreated water from lakes, streams, springs, or any other untreated sources.
  • Avoid touching human or animal feces.
  • Wash hands after using the toilet, after changing diapers, and before handling food or eating.