Cyclospora Infection (Cyclosporiasis)

Reviewed: March 2023

What is Cyclospora infection?

Cyclospora is a microscopic (tiny, not seen without a microscope) parasite that can affect the intestinal tract and cause diarrhea (loose stool/poop) in those who get infected. People get infected when they eat or drink food or water contaminated with the parasite.

Who gets Cyclospora infection?

Cyclospora infections can occur in people of all ages. It is associated with foreign travel to tropical or subtropical regions of the world. In the United States, outbreaks have been linked to various types of imported fresh produce.

How is Cyclospora spread?

Cyclospora is spread by eating or drinking contaminated food or water. Infection spreading directly from one person to another is unlikely. Outbreaks in the United States have been linked to various types of imported fresh produce, such as cilantro, salad mix, basil, snow peas, and raspberries.

What are the symptoms of Cyclospora infection and when do they appear?

Watery diarrhea (loose stool/poop) is the most common symptom. It may last a few days to a month or longer. Symptoms may go away and then come back during the course of infection. Other symptoms may include loss of appetite, stomach cramps, weight loss, muscle aches, nausea (a feeling of sickness in the stomach), vomiting, and tiredness. Symptoms appear approximately one week after consuming contaminated food or water.

How is Cyclospora infection diagnosed?

Cyclospora infection is diagnosed by identifying the parasite during a microscopic examination of the stool (poop) in a laboratory test.

How is Cyclospora infection treated?

The recommended treatment involves a combination antibiotic called trimethoprim-sulfamethoxazole, also known as Bactrim, Septra, or Cotrim. People with diarrhea (loose stool/poop) should also rest and drink plenty of fluids.

Does past infection with Cyclospora make a person immune?

People can be reinfected with Cyclospora if they are exposed to the parasite again.

What can be done to prevent the spread of Cyclospora infection?

Avoid water or food that may be contaminated with feces (poop). Thoroughly wash all fresh produce, including herbs, fruits, and vegetables. When traveling to a country with poor sanitary conditions, it is important to drink water from sources you know to be safe such as sealed bottled water, boiled tap water, and carbonated (bubbly) water from sealed cans. It is also important to be aware of the foods you eat that you did not peel/wash yourself, including fresh fruit or vegetables, as they may be contaminated with Cyclospora.