LANSING, Mich. (WZMQ) – Michigan’s cyclosporiasis outbreak has grown to more than 3,700 confirmed cases, and state health officials say that number is likely to keep rising in the days ahead.
Dr. Natasha Bagdasarian, Michigan’s Chief Medical Executive, said the parasite spreads through produce that comes into contact with water contaminated by human feces, which can happen either in the field or during processing. Investigators in Michigan have interviewed more than 1,700 people who tested positive for cyclosporiasis, and the strongest pattern to emerge so far points to bagged lettuce, though no specific brand, grower or lot has been publicly identified.
The delay in identifying a source isn’t for lack of effort, Bagdasarian said. The interviews alone have taken more than 1,000 staff hours, with local health department employees pulled off their regular duties to work the outbreak full time.
“We have well over 1,000 staff hours that have gone into just the interviews,” Bagdasarian said. “Folks have been pulled off of their day-to-day jobs and have been pulled onto working on this outbreak and nothing else.”
Michigan has been sharing findings publicly since July 4, when it first issued guidance on handling produce. As the lettuce connection strengthened, that guidance narrowed: buy whole heads of lettuce, remove the outer leaves, and thoroughly wash what remains before eating.
Part of the challenge is timing. Cyclospora has an incubation period that can stretch up to two weeks, and people often wait to seek care once symptoms start. That lag means the case count reported today reflects exposures that may have happened well over a week ago, according to Bagdasarian, and it’s a major reason the numbers haven’t leveled off yet.
Because the contamination likely occurred outside Michigan, state officials say the next phase of the investigation is largely out of their hands. Federal agencies, including the CDC and FDA, are now responsible for coordinating between states to trace the outbreak back to a specific grower or lot.
“If you develop diarrhea or other symptoms, it’s important to seek medical attention right away so that you can get tested and then treated,” Bagdasarian said. “There’s an antibiotic that works against this parasite.”
Anyone who develops watery diarrhea or other symptoms is urged to contact a health care provider and ask to be tested, Bagdasarian said. Cyclosporiasis can be treated with a combination antibiotic, but left untreated, symptoms can last for weeks.
