The Windsor-Essex County Health Unit (WECHU) is providing health care providers with an update regarding a significant increase in cyclosporiasis cases in Windsor-Essex County (WEC) since the last report. To date, 24 cases of cyclosporiasis have been reported in 2026, compared with a 5-year average of 3 cases. Travel remains to be a common exposure among cases to Mexico and Michigan.
This increase coincides with a large ongoing cyclosporiasis outbreak in Michigan, where the Michigan Department of Health and Human Services (MDHHS) has reported more than 10,700 cases as of July 30, 2026. Michigan health officials have indicated that lettuce and salad greens are a potential source of the outbreak, although investigations remain ongoing.
The WECHU continues to encourage health care providers to consider testing for cyclosporiasis in patients presenting with compatible signs and symptoms, particularly those who have recently travelled to Michigan or several other states.
Clinical Signs and Symptoms
Signs and symptoms typically develop 2 to 14 days after exposure and may include:2
- Watery diarrhea
- Nausea
- Loss of appetite
- Cramping and abdominal pain
- Weight loss
- Fever
- Feeling tired and unwell
Specimen Collection and Testing
Diagnosis requires confirmation through Enteric Protozoa PCR or Cyclospora PCR testing. A stool specimen should be submitted using a Cary-Blair vial or a sterile, empty vial. For additional information on testing, refer to Public Health Ontario - Enteric Protozoa - PCR.
References