Wisconsin health professionals are encouraging residents wash their produce after hundreds of people in Michigan have been sickened by a parasitic intestinal illness
Michigan state health officials have confirmed 681 cases of cyclosporiasis, according to the Detroit Free Press
The microscopic parasite cyclospora infects people through contaminated water or food, causing severe diarrhea. It’s often spread through fresh produce such as lettuce, herbs and raspberries — especially foods that are imported from developing countries in Central and South America
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No specific type of produce or grower has been identified in the current outbreak, according to the Michigan Department of Health and Human Services
Cases of cyclosporiasis are diagnosed every year across the U.S., including in Wisconsin. Most infections happen during the late spring and summer months
Dr. David McNamara, infectious disease doctor at Emplify Health by Gundersen in La Crosse, said most cases are sporadic and are often acquired while traveling internationally
In a healthy adult, cyclosporiasis will cause diarrhea for several weeks or up to three months before resolving. It’s a much longer timeline than other types of food poisoning from bacterial infections
McNamara said cyclosporiasis can also be harder to treat, especially for sensitive groups including people with weakened immune systems, those who are elderly and young children
“Those patients are going to be much more vulnerable to getting a bad diarrhea, and they’re going to be a lot harder to successfully treat with antibiotic or antiparasitic drugs,” he said
Since May 1, 35 cases of cyclosporiasis have been reported to the Wisconsin Department of Health Services. An agency spokesperson said in an email the total is approximately double the number reported during the same period last year
But the increase is from infections acquired while traveling internationally rather than a domestic outbreak like the one in Michigan. The DHS spokesperson said fewer than 10 infections this year have been acquired by Wisconsinites within the U.S
Thoroughly washing fresh produce is the best way to reduce the risk of becoming infected with the parasite. Health officials recommend scrubbing firmer fruits and vegetables and opting to discard the outer leaves from a head of lettuce
McNamara said people with the highest risk of severe illness may be safest cooking their fruits and vegetables, or opting for an alternative to items like fresh berries
“It may be safer to try and go with frozen raspberries and strawberries, which aren’t quite as high of a risk, we think, as fresh fruit,” he said
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