Snohomish County health officials declare end of measles outbreak

Published 11:30 am Tuesday, April 7, 2026

EVERETT — The Snohomish County Health Department declared the end of the measles outbreak Tuesday, according to a department press release.

Health officials announced the outbreak Jan. 15. There have been 14 total cases. Although the last reported case was Feb. 17, health officials are urging residents to stay alert for future measles cases.

Health officials can declare a measles outbreak over after six weeks with no new cases. The last day of infectiousness for one of the measles cases was Feb. 21.

This year, 33 measles cases have been recorded in Washington, according to state data. Most recently, two cases were reported Friday in Walla Walla and Kittitas counties. King County also reported two cases last week.

“After strong community support and dedicated work by our health department teams, we’re happy and relieved that the current outbreak is over,” Snohomish County Health Officer Dr. James Lewis said in the release. “That being said, we fully expect additional cases of measles to be introduced into Snohomish County as evidenced by ongoing exposures across the state.”

Since the department declared the outbreak, staff have engaged in case investigation, vaccination efforts, contact tracing and symptom monitoring, the release said. The outbreak cost the department more than $104,000, more than 1,000 hours of staff time and about 300 phone calls.

“We’re grateful the communities worked with us,” Health Department Director Kim Van Pelt said in the release. “If not for their cooperation and the hard work of our team, we almost certainly would have seen more cases than we did.”

All Snohomish County residents who became infected during the outbreak were unvaccinated, the release said. Nine out of 10 unvaccinated people will likely contract measles if exposed to an infectious patient, health officials said.

Two shots of the measles, mumps and rubella vaccine provide a lifetime of protection against the three diseases. The vaccine is 97% effective against measles, health officials said in the release.

This summer, Seattle is hosting the World Cup, which is expected to bring thousands of international travelers to the area. In addition to regular spring and summer travel, the event could lead to more measles and other communicable diseases, according to the release.

“We know we’re going to be dealing with more cases and more exposure sites,” Lewis said. “With spring travel now starting, this is a perfect time to know your immunization status. If you aren’t immunized, or can’t find proof of it, we recommend getting the MMR vaccine as soon as possible.”

Jenna Peterson: 425-339-3486; jenna.peterson@heraldnet.com; X: @jennarpetersonn.