Cyclospora map: The diarrhea parasite outbreak has now expanded to 9 states — see the hotspots

• The number of states affected by a huge outbreak of cyclosporiasis has risen to nine, health officials said.
• People got sick after eating lettuce sold by Taylor Farms in: IL, IN, KS, KY, MI, OH, OK, PA, and WV.
• We made two maps to show the states with the most reported cases, and where food has been recalled.

The Midwest remains the hotspot of a major outbreak of cyclosporiasis, a parasitic infection that can trigger weeks of watery diarrhea.

On Friday, federal health officials said what was previously a five-state outbreak, with most cases reported in Michigan and Ohio, now involves nine states: Illinois, Indiana, Kansas, Kentucky, Michigan, Ohio, Oklahoma, Pennsylvania, and West Virginia.

According to the CDC, 1,947 cyclosporiasis cases have been linked to iceberg lettuce distributed by Taylor Farms to Taco Bell locations in the nine states. A total of 98 people are known to have been hospitalized, and no deaths have been reported. People started falling ill between June 22 and July 20.

Cyclospora season in the US typically runs between May 1 and August 31, according to the CDC, and the multi-state outbreak is a subset of illnesses reported nationwide in 41 states. Cases could continue to rise until September.

Katelyn Jetelina, assistant professor adjunct of epidemiology at Yale School of Public Health, wrote in her public health newsletter, Your Local Epidemiologist, on July 21 that several outbreaks are running at once, including one suspected to be caused by cilantro in New York. She described the Midwest outbreak as “its own beast.”

On July 17, Taylor Farms voluntarily recalled iceberg lettuce from the US that was sourced from central Mexico, as shown below.

Taylor Farms told shoppers who had bought iceberg lettuce distributed June 29th through July 16th in the following states to not consume it and throw it out: Alabama, Arkansas, Connecticut, Florida, Georgia, Iowa, Illinois, Indiana, Kansas, Kentucky, Louisiana, Massachusetts, Maryland, Michigan, Missouri, Mississippi, North Carolina, New Hampshire, New Jersey, Ohio, Oklahoma, Pennsylvania, South Carolina, Tennessee, Texas, Virginia, and Wisconsin.

However, other foods can’t be ruled out.

(As Business Insider’s Dan DeFrancesco explained in an edition of the Business Insider Today newsletter, the situation is a little more complex than we get into here.)

Jetelina said iceberg lettuce was recalled in 27 states “due to a combination of the complexity of food distribution networks and continued uncertainty around where people are most impacted.”

Posing the question, “When will this end?” Jetelina said, “No one knows. Either the contaminated food works its way out of circulation, or it takes a few weeks, the temperatures get cool, and the parasites no longer mature on produce (basically killing themselves off). It’s hard to tell from the data alone if this outbreak is coming to a close given that it’s significantly delayed.”

Why states and the CDC have different case counts

There are a number of potential sources of confusion in this outbreak, including differing state and federal case counts, and how the FDA and Taylor Farms have shared information on the suspected source of infections.

As of July 21, at least 11,276 cases of cyclosporiasis had been reported across 46 states in 2026, according to Georgetown University’s Health Security Operations Center, which is tracking state and national-level data. Some state health departments are tallying cases as part of the ongoing outbreak, while others include all cases reported in 2026 in their figures.

In contrast to Georgetown’s count, the CDC said in its cyclosporiasis update on July 24 that it had confirmed 4,173 domestic cases of cyclosporiasis, and was aware of more than 7,400 cases that need further analysis to confirm.

How to avoid cyclospora

Cyclospora spreads through contaminated food and water, and symptoms, including watery diarrhea, nausea, and stomach cramps, can take up to two weeks to show, making it difficult to trace back to a definitive source. The parasite is resistant to disinfectants, and washing food doesn’t guarantee its removal, as it is particularly good at sticking to produce.

Health authorities say in order to definitively kill the parasite, cook foods to at least 158 degrees Fahrenheit. Buying whole heads of lettuce and peeling back the outer layer of leaves rather than choosing pre-washed, bagged, or pre-mixed salads is also a good move, if you are more risk-tolerant.