What is cyclosporiasis?

Cyclosporiasis is a diarrheal illness caused by a tiny parasite called Cyclospora. The parasite is found in the intestine of an infected person's and is passed in their feces (stool). Cyclospora is common in developing countries, and in particular, tropical and subtropical countries where sewage and water treatment is poor.

How is cyclosporiasis spread?
People become infected with Cyclospora by eating food or drinking water contaminated with the parasite. In Canada, cyclosporiasis is seen most often in travellers to regions where the parasite is common, or from eating contaminated fruits and vegetables imported from these regions. Cases of cyclospoiasis infection have been linked to imported berries, herbs and several types of lettuce. This occurs when fresh fruit and vegetables come in contact with water or soil contaminated by infected farm workers. People with cyclosporiasis pass immature parasites in their feces, which then develop in the environment (for example, in soil) into mature parasites, which are then capable of causing infection in others. Cyclospora cannot be spread by direct person-to-person contact.  
What are the symptoms of cyclosporiasis?

Symptoms usually start within a week of being infected. Most people experience some or all of the following symptoms: watery diarrhea, vomiting, stomach cramps, bloating and gas, loss of appetite, weight loss and tiredness. The illness may be more severe in young children, older adults and people with weakened immune systems.

What is the treatment for cyclosporiasis?
Some people may recover from cyclosporiasis on their own without treatment. However, without treatment the illness can persist for several weeks to months and symptoms may go away and come back. The infection responds well to antibiotic treatment, which is available from your health care provider, but even with treatment, it may take time for the gut to return to normal. Always drink plenty of liquids when having diarrhea, to prevent dehydration.
Are there any restrictions or special considerations for people ill with cyclosporiasis?
Anyone who is infected with Cyclospora and has symptoms of diarrhea should stay at home. People whose work involves preparing or handling food, or providing child care or health care, and children who attend daycare, should remain at home until the diarrhea has stopped for at least 24 hours. 
How can I protect myself against cyclosporiasis?
To prevent becoming ill with cyclosporiasis:
  • Avoid local water when travelling to countries where the water supply is uncertain; instead use only sealed bottled water or treated (chemically disinfected or boiled) water for drinking, brushing teeth, preparing foods, making ice and cooking
  • Beware of raw foods washed in local water when travelling; eat only cooked food and fruit that can be peeled after it has been washed with water from a safe source
  • Avoid swallowing water when swimming, and do not drink untreated water from lakes and rivers
  • Wash raw fruits and vegetables well with clean running water before eating (washing imported produce does not always remove the parasite)
  • Eat fruits and vegetables that have been frozen, as freezing may kill the parasite
  • Always wash hands well with soap and water for at least 15 seconds before and after preparing food, before eating, after using the toilet, after changing diapers, after handling pets or their feces, and anytime hands may be dirty 
What is Ottawa Public Health's role?
Ottawa Public Health (OPH) must be notified by health care providers and laboratories when a person is infected with cyclosporiasis. OPH conducts an investigation to potentially determine the cause or source of the infection, provide education to the infected person and their close contacts, and follows up with the infected person's health care provider, as needed.

For further information, call Ottawa Public Health at 613-580-6744, or visit

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