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Diarrhea-Causing Parasite Cases Grow To Over 1,200 In Michigan

Officials said 40 of those cases have resulted in hospitalization.

More than 1,200 Michiganders have been diagnosed with a foodborne parasite illness that can cause weeks of diarrhea, according to the Michigan Department of Health and Human Services.

As of 9:30 a.m. Thursday, state health officials reported 1,251 cyclosporiasis cases across the state since June 22, making Michigan the hardest-hit state in the nation.

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Officials said 40 of those cases have resulted in hospitalization.

The cases have all been found in southeastern Michigan, including in Monroe, Lenawee, Washtenaw, Wayne, Shiawassee, Jackson, Oakland and Livingston counties, officials said.

Cases have also been reported in 28 other states, including Illinois, Ohio and Wisconsin, according to the CDC.

Officials are still trying to identify the source but warned some fruits and vegetables may be linked to the outbreak.

What Is Cyclosporiasis?

Cyclosporiasis is an intestinal illness caused by the Cyclospora parasite, which is commonly found in developing countries and spread by food or water contaminated with feces.

It infects the small intestine (bowel) and usually causes frequent, watery and explosive diarrhea.

Symptoms usually begin about a week after someone consumes contaminated food or water, though they can appear as soon as two days or more than two weeks later. Watery diarrhea is the most common symptom.

Cyclosporiasis is not usually life-threatening, but dehydration from frequent bouts of diarrhea can cause severe illness, particularly among younger or older people and those who have weakened immune systems.

How To Prevent Cyclosporiasis

The best way to prevent infection with a parasite is to avoid food or water that may have been contaminated.

Officials recommend properly preparing fruits and vegetables by thoroughly washing them before cutting, eating and cooking.

As Michigan officials investigate the potential source, they recommend consumers buy whole heads of lettuce rather than prewashed, bagged lettuce or salad mixes and to remove the outer two to three leaves before washing the remaining leaves under running water.

Previous Cyclosporiasis Outbreaks

There isn't much data on Cyclosporiasis cases since outbreaks have eclipsed 1,000 cases only a handful of times in the last 20 years. The last outbreak happened in 2019 when Mexican basil sickened more than 2,400 people across the U.S. and Canada.

University of Minnesota foodborne illness researcher Melanie Firestone told the Associated Press most tests to detect food poisoning are not geared to check for Cyclospora.

It can also be challenging to trace food contaminated with Cyclospora because food distributors may ship the food to both grocery stores and restaurants.

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