Michigan cyclosporiasis cases jump to 2,640 as lettuce emerges as potential source and Taco Bell is investigated

Outbreak scale

A cyclosporiasis outbreak that began on May 1 has spread to 31 states, with the Centers for Disease Control and Prevention confirming 843 cases and 86 hospitalizations as of July 9. That tally is a significant undercount: Michigan alone reported 2,640 cases and 44 hospitalizations by July 13, a 69 percent jump from the previous Friday, and The New York Times has independently verified at least 4,800 infections nationwide. No deaths have been recorded, but epidemiologist Caitlin Rivers of Johns Hopkins said the year is "on track to be the biggest year on record" for the parasite in the United States, surpassing the annual average of about 2,800 cases since 2016.

Michigan surge and lettuce link

Michigan, which normally sees 40 to 50 cyclosporiasis cases per year, has borne the brunt of the surge. On Monday the state Department of Health and Human Services identified leafy lettuce or salad greens as the leading suspected source after interviewing more than 1,000 patients. Chief medical executive Natasha Bagdasarian cautioned that the finding is not definitive.

Early information has shown lettuce as a common product that regularly comes up during the investigation.

The department said other food items cannot be completely ruled out, and no specific grower or supplier has been named. Past U.S. outbreaks have been tied to bagged salad mixes, raspberries, basil, cilantro, snow peas and snap peas, often imported and eaten raw.

Taco Bell under scrutiny

Federal and state investigators are examining whether Taco Bell is connected to the outbreak, according to two individuals familiar with the inquiry who spoke to The Washington Post on condition of anonymity. Last week, signs posted at some Detroit-area Taco Bell locations warned customers the chain was "currently unable to sell Lettuce, Cilantro Onion, Pico de Gallo, and Guacamole due to a nationwide recall." One person familiar with the investigation described the move as a prudent safeguard, though not all infected individuals reported eating at the chain, suggesting the outbreak is not confined to Taco Bell. The company has not responded to multiple requests for comment.

Why tracing is so hard

The cyclospora parasite presents unusual detection challenges. Symptoms often take one to two weeks to appear, making it difficult to pinpoint a meal.

With most food-related illnesses, people tend to experience symptoms within a couple of hours, making it easier to find the food that caused them.

Steven Manderach, executive director of the Association of Food and Drug Officials, compared the task to "detecting a microscopic portion of a needle in a haystack." Laboratory testing requires washing large volumes of produce and then concentrating the runoff. Some experts also pointed to budget and staff cuts at the Department of Health and Human Services under Secretary Robert F. Kennedy Jr. as a factor complicating the federal response.

Protection and the road ahead

Without a confirmed source, health officials are urging consumers to wash all produce thoroughly under cold running water for at least one minute, cook vegetables when possible, and wash hands before handling food. Environmental biologist Don Stoeckel of Cornell Produce Safety Alliance cautioned against avoiding produce altogether.

It's a significant outbreak, but it's not like every piece of produce is contaminated. Remember that produce is part of a healthy diet.

The CDC expects case counts to keep rising through August 31, the end of the peak season. The agency said more than 1,500 additional reports were awaiting analysis as of July 9, and state-level counts will continue to climb as delayed confirmations arrive.