King County Public Health closes investigation into McMenamins Bothell pool outbreak

Key points

• Fourteen people reported illness after swimming at the McMenamins Anderson School pool on August 29 or 30.
• Symptoms included nausea, diarrhea, abdominal cramps, and fever, beginning between September 3 and 5.
• Laboratory tests confirmed cryptosporidiosis in four of the five individuals who were tested.
• No hospitalizations or deaths were reported in connection with the outbreak.
• Public Health inspected the facility on September 21 and found no violations or fecal incidents.
• Officials determined the outbreak is over and emphasized that the parasite survives in chlorine-treated water.

Background

This local incident follows a broader pattern of waterborne parasite concerns in 2026, as noted by KPTV, which linked the Cryptosporidium strain to a wider U.S. outbreak of explosive diarrhea earlier this year. Our archive from October 1 confirms the closure of this specific investigation, highlighting that while the facility was compliant with regulations, the parasite's resilience remains a significant public health challenge for public swimming venues.

How outlets are covering it

KOMO and KPTV provide detailed timelines, noting that symptoms began between September 3 and 5, while KIRO 7 News emphasizes the contagious nature of the parasite. All three outlets agree that the facility was well-maintained and followed King County health and safety requirements. KPTV uniquely contextualizes the local event within a national trend of Cryptosporidium outbreaks in 2026. KOMO and KIRO 7 News both stress the importance of showering before swimming and avoiding pool use for two weeks after recovering from diarrhea or vomiting.

Why it matters

This case highlights the limitations of standard chlorine treatment against certain parasites, even in well-maintained facilities. It underscores the importance of individual hygiene and adherence to exclusion policies for swimmers with recent gastrointestinal illness to prevent community spread in public recreational spaces.

What to watch

The outbreak is considered over, and no further action is required from the facility. Public Health officials continue to monitor for any new cases, though none have been reported since the initial cluster. The pool remains open to the public, with Bothell residents eligible for free admission.