Measles remains a growing concern in Washington as U.S. surpasses 1,100 cases

The Washington State Department of Health (DOH) has confirmed 26 measles cases across four counties this year, marking an increase from the three cases reported in a single county Jan. 16, a news release from the DOH stated.

The 26 measles cases reported during the first two months of 2026 are already more than double the 12 cases reported statewide in all of 2025. More than half of the measles cases reported in Washington in 2026 are linked to an outbreak with three or more related cases, according to the release. By contrast, there were no outbreaks of measles reported in 2025.

Nationally, the United States has now surpassed 1,100 measles cases in 2026. The increase reflects a resurgence of a disease that was declared eliminated in the United States in 2000.

Nearly 80% of reported cases in Washington this year are in children, including 16 cases among kids ages 5-17 and four cases in children younger than 5. Confirmed cases have been identified in Snohomish County (14 cases), Clark County (eight cases), Stevens County (three cases), and Kittitas County (one case). All measles cases have occurred in people who are unvaccinated (24 cases) or whose vaccine status is unknown (two cases).

“MMR vaccine saves lives and is our best defense against measles,” said Dr. Tao Sheng Kwan-Gett, state health officer. “Though measles was declared eliminated in the United States 26 years ago, we are seeing more and more cases linked to outbreaks in other states, particularly in families that are unvaccinated. You just never know when or where your family might be exposed to measles, so make sure everyone is up to date on MMR vaccine, one of the best-tested vaccines around.”

DOH continues to work closely with tribal partners and local health jurisdictions to help investigate cases, facilitate laboratory testing and give MMR vaccines.

DOH is also conducting community outreach to provide education on measles prevention and assist specific settings, such as schools, in preparing to respond to potential measles cases.

This year DOH began conducting whole genome sequencing on laboratory-confirmed measles cases. Genetic sequencing maps the virus’s genetic “fingerprint,” which helps doctors and scientists determine whether cases are connected to each other or if they stem from separate introductions. Current analysis indicates Washington’s 2026 measles cases came from multiple introductions from outside the state.

The measles, mumps and rubella (MMR) vaccine is safe and highly effective, according to DOH.

One dose is 93% effective, and two doses are 97% effective. Getting the MMR vaccine is safer than getting sick with measles, and it protects families and communities, the release stated. Children typically get the MMR vaccine at 1 year old and again at 4 years of age, but there is specific guidance for people living in or traveling to places where there is an active outbreak, including children under 1 year. Adults who haven’t been vaccinated can get the MMR vaccine as well.

Most people who get measles are not vaccinated.