Washington State’s most significant public health agency says there are no common foods, restaurants or any other known sources for a shigellosis outbreak at a local kindergarten.

Public Health for King County is continuing to investigate the shigellosis outbreak at Cascade Ridge Elementary School in Issaquah, WA, located east of Seattle. Since Monday, Nov. 26, the agency has learned of at least 16 people with the illness. The symptoms are consistent with shigellosis, including vomiting, diarrhea, and fever.

Eight of the 16 are adults and eight are children. The onset of the illnesses ranges from Nov. 4 to 29. Public Health reports most have recovered. One did require hospital care.

Environmental health investigators from Public Health visited the Cascade Ridge Elementary, including its classrooms and kitchen on Nov. 28. Investigators worked with the school nurse and principal to identify any other ill staff or students outside of the kindergarten classrooms.

“Our Environmental Health investigators did not identify any food handling practices in the kitchen that could increase the risk for Shigella infection among students or staff,” Public Health said in a statement released on Friday afternoon.

The agency said it found no ill food workers.

“Recommendations for a thorough cleaning and disinfection of common areas and surfaces was recommended and completed by the school on Nov. 28,” the agency statement continued. “Public Health will continue to work with Cascade Ridge Elementary School staff to help prevent additional people from becoming sick.”

Four who became sick tested positive for Shigella sonnel. There is not yet lab confirmation for the others, but all the symptoms suggest Shigella infections.

Shigellosis can be a severe illness. Any school children or staff that experience vomiting, diarrhea, or fever should remain at home until they’ve been symptom-free for at least 24 hours.

Public Health will continue to work with the Cascade Ridge Elementary School and advises hand-washing and strict kitchen sanitation practices to avoid spreading the pathogen.

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