9 cases of cyclosporiasis reported in Boone County this week; Boone Health reports 5 hospitalizations

COLUMBIA, Mo. (KMIZ)

Nine cases of cyclosporiasis have been reported in Boone County this week, according to the Columbia/Boone County Public Health and Human Services.

The PHHS reported eight cases earlier in the day, but an extra case was confirmed at 4 p.m. to ABC 17 News.

Boone Health spokesman Christian Basi told ABC 17 News that Boone Health has five hospitalizations because of the parasite. Four of those patients are Boone County residents.

A University Hospital spokesman confirmed the hospital has treated people in their emergency department.

The release says the PHHS is working with the state’s Department of Health and Senior Services “to determine if this increase in cases is related to the national outbreak. Initial investigations indicate local transmission.”

State health officials said earlier this week that the diarrhea-causing illness – which is contracted by eating contaminated produce or water – reported in Missouri were believed to be connected with travel.

The release from the PHHS says symptoms begin about a week after exposure and can include “frequent diarrhea, weight loss, bloating, nausea and fatigue. Less common symptoms include vomiting and a low-grade fever.”

The most cases reported in Boone County in the past five years was 10 in 2023, previous reporting shows.

Earlier this week, PHHS told ABC 17 News there were four cases reported in 2026. Spokesperson Austin Krohn said those cases were travel-related and were not connected to the national outbreak.

Risk of exposure can be reduced by washing produce, even if produce is labeled as pre-wash.

Check back for updates.