Seattle

Epidemiological Brief

As of 27 July 2026, Seattle is classified at MEDIUM epidemic risk (composite score 35.1). Pertussis (whooping cough) is the dominant signal at 9.96 cases per 100,000 — the highest pertussis incidence among all 16 host cities, at 100% of the reference maximum — reflecting Washington State's ongoing elevated whooping cough transmission. This warrants specific outbreak-response readiness at all venues. Influenza ILI is significantly elevated at 6.3%, well above typical July baseline. Measles incidence stands at 0.41 cases per 100,000 (50.7% of reference). Mpox is detected at 0.16 cases per 100,000, with the adjusted contribution attenuated by the mitigation factor. COVID-19 activity is low at 0.30 cases per 100,000. Dengue cases are travel-associated only (0.09 cases per 100,000) with no local vector competence. Wastewater-based epidemiology (ATCP-73RE) is actively monitoring COVID-19 and influenza signals. Conditions are mild (18 °C, 80% humidity, no precipitation), with 130 international arrivals. Recommended actions include surge capacity for pertussis case investigation and contact tracing, venue-level respiratory hygiene advisories, MMR vaccination verification at fan registration, mpox clinical pathways at medical posts, and close liaison with Washington State Department of Health for real-time pertussis cluster reporting throughout the tournament.

Model SCEME v3.1 · Updated July 27, 2026

Please consult a local doctor or pharmacist for guidance and medication.