Diarrhea-causing parasite infecting more than 1,200 in Michigan has not spread to Canada: PHAC

The Public Health Agency of Canada says the outbreak of a diarrhea-causing parasite that has infected more than 1,200 people in Michigan has not spread to Canada based on current information. 

The midwestern state announced an outbreak of cyclospora last week, saying more than 170 people had been infected. 

That number climbed to 1,251 Thursday, a surge of nearly 260 cases from a day earlier. 

Public health officials in Michigan say the source of the outbreak is still unknown and that the number of people getting sick from the parasite is unusual compared to the 50 cases typically reported per year.

Cyclospora most commonly causes watery diarrhea for six to seven weeks, in addition to bloating and gas, nausea, tiredness, stomach cramps, loss of appetite, weight loss and a mild fever.

The parasite can contaminate food when the feces of an infected person gets into the water supply used for crops or in food processing or packaging. 

Mark Johnson, a spokesperson for the Public Health Agency of Canada, says no cyclospora outbreaks are currently being investigated in Canada.

Johnson says cyclospora is not in the country’s drinking water. 

It is also not commonly found on food in Canada, but it can be imported from other countries, such as Peru, Cuba, India, Nepal, Mexico, Guatemala, Southeast Asia and the Dominican Republic. 

There is usually an increase of cases in summer and spring when fresh fruit and vegetables are imported into Canada. Foods that have been linked to the parasite include basil, cilantro, raspberries, blackberries, mesclun lettuce, snow and snap peas, and pre-packaged salad mix.

Cooking fresh fruits and vegetables imported from countries where cyclospora is found or sticking to fresh produce grown in Canada can help prevent infection, PHAC says. 

The illness, called cyclosporiasis, is diagnosed with a stool sample and treated with a prescription medication. Symptoms usually improve within two to three days after starting the medication, but it can take several weeks for intestinal problems to disappear.

This report by The Canadian Press was first published July 9, 2026. 

Canadian Press health coverage receives support through a partnership with the Canadian Medical Association. CP is solely responsible for this content.

By Hannah Alberga | Copyright 2026, The Canadian Press. All rights reserved.