Published August 10, 2026 at 11:12 AM CDT

Missouri health officials say 1,577 people in the state have now tested positive for cyclosporiasis, an intestinal illness caused by a parasite that has spread rapidly across the United States this summer.

The new numbers released Sunday by the Missouri Department of Health and Senior Services reflect a 44% increase in confirmed cases from the previous week.

The federal Centers for Disease Control and Prevention has identified Missouri as one of 15 states where contaminated iceberg lettuce has made people sick. Illinois is also on the list. Health officials there said 995 people have either confirmed or probable cases of cyclosporiasis.

On July 17, Taylor Farms issued a recall of all iceberg lettuce sourced from central Mexico. The CDC is also investigating other outbreaks of illnesses of cyclosporiasis nationally that are from other sources and are unrelated to this outbreak.

Cyclosporiasis is a diarrheal illness that enters the human digestive system through food or water contaminated with human waste. Most people recover on their own, and it is rarely fatal. However, officials in Michigan announced earlier this month that two people there died after becoming ill.

The state health department said "both individuals had significant underlying health conditions that may have been impacted by cyclosporiasis and dehydration."

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