Public health officials have confirmed the measles outbreak in Snohomish County has grown to six confirmed cases. This marks a sharp escalation from the initial three cases identified just two weeks earlier.

According to a media release from the Snohomish County Health Department, three new cases were confirmed as of January 27, 2026—all in unvaccinated children. One of the new cases involved a child who attended an afternoon service at Slavic Christian Church Awakening in Mukilteo on January 18, 2026, between 2 p.m. and 6 p.m. Anyone present during that service may have been exposed to measles.

Previously, three unvaccinated children had tested positive on January 14, linked to exposure from a measles‑infected family that traveled from South Carolina between December 27, 2025, and January 1, 2026. That family visited several public venues in Everett, Mukilteo, Marysville, and at Seattle‑Tacoma International Airport while infectious. These exposure sites, along with school and medical settings on January 9 and 13, respectively, already prompted widespread public notification.

The Washington State Department of Health confirms this is the state’s first measles outbreak since 2023. As of February 3, the total number of confirmed measles cases in Washington stands at 10. Of these:

• Seven are in Snohomish County (70%).
• The remaining three are in Clark, Kittitas, and Stevens counties (10% each).
• Hospitalizations and deaths remain at zero.
• Nearly all cases (90%) involve unvaccinated individuals.

Health officials emphasize that because most residents are vaccinated, the general public’s risk remains low. Yet, the next two or three weeks are considered critical, as additional cases may emerge—particularly among those without documented immunity.

Across Washington state, vaccination coverage remains below the 95% threshold needed for herd immunity. Only four counties—Adams, Garfield, Wahkiakum, and Yakima—met that benchmark among kindergarten entrants during the 2024–25 school year. Declining rates in populous regions, including King County (92.4%), heighten concern over the potential for further measles spread.