Michigan sees rapid rise in cyclospora infections as health officials urge testing and cooking precautions
More than 1,500 Michigan residents have been infected with the cyclospora parasite since late June, prompting doctors to stress testing, antibiotic treatment and thorough cooking of produce.
Michigan health officials report that over 1,500 people have contracted cyclosporiasis, a parasitic illness that causes watery diarrhea, since June 22. The number of cases is increasing by 20% to 30% daily, according to infectious disease specialist Dr. Anurag Malani, who said the true count is likely higher because not everyone can access diagnostic testing and some infections are asymptomatic.
The parasite, Cyclospora cayetanensis, spreads through ingestion of food or water contaminated with fecal matter. It is not thought to spread directly from person to person, and most infections in the United States have been linked to imported fresh produce such as bagged salads, cilantro, basil and raspberries. The current outbreak’s source remains unidentified.
Patients typically present with persistent diarrhea, abdominal pain, nausea and, in severe cases, dehydration and electrolyte disturbances. As of July 10, at least 44 Michigan residents had been hospitalized. The state’s most affected counties include Monroe, Wayne and Washtenaw.
Doctors recommend stool testing to confirm infection. Two options are available: a standard ova and parasite exam, costing about $20 and taking three to five days, and a molecular panel that detects multiple pathogens, including cyclospora, for roughly $475 with results in about a day.
Treatment with the antibiotic trimethoprim-sulfamethoxazole (Bactrim or Septra) is advised for confirmed cases, especially because symptoms can last four to six weeks. Those unable to take sulfa drugs should discuss alternatives with their physician.
Preventive measures focus on thorough washing and cooking of high-risk produce. Heating food to at least 158°F (70°C) reliably kills the parasite, while washing reduces but does not eliminate contamination, particularly on raspberries. The Michigan Department of Health and Human Services advises avoiding pre-washed bagged greens, discarding outer lettuce leaves, and using hot water and soap or a dishwasher for utensils and surfaces.
Experts note that cyclospora is not known to infect pets and that climate change could expand its geographic range in the future. Anyone experiencing prolonged gastrointestinal symptoms should seek medical evaluation and testing before taking antibiotics.