Cases of an explosive diarrheal parasite continue to skyrocket in Michigan, which is reporting 1,251 cases as of July 9. Of those, 44 were hospitalized. Meanwhile, across the border in Ohio, cases are also quickly rising, with news reports of a case total over 500.
The outbreak in Michigan began with two cases reported on June 22 and rose steeply at the start of July. The Michigan Department of Health and Human Services (MDHHS) reported 572 cases on July 4. On Wednesday, July 8, 239 cases were reported, the highest single-day tally so far. The current total of 1,251 cases includes 159 case reports received on July 9.
The epicenter of the outbreak is in the southeastern corner of the state, where health officials from multiple jurisdictions are working furiously to identify and interview cases to track the source or sources of the parasite, which spreads through food and water.
Microscopic menace
That parasite is Cyclospora cayetanensis, a microscopic, single-celled protozoan that is shed in feces and typically infects humans in the US via contaminated produce, though it can also spread in contaminated drinking water. In recent years, the US has been logging between 2,000 and 5,000 cases each year, with the parasite thriving in the summer months. Cases are typically highest in June and July.
While it is still unclear whether this will be a record year for cyclosporiasis cases nationally, it’s certain that Michigan is experiencing an unprecedented outbreak. In past years, the state’s yearly case totals have mostly been around 50; the case tally just in July is already 25 times larger than that usual number. And cases continue to rise, while investigators have not yet identified how people are getting sick.