UPDATE: Public Health—Seattle & King County sent out another measles warning this weekend: A Canadian traveler infected with measles spent three hours at Seattle-Tacoma International Airport on Jan. 22. The person visited the following places at the airport between 4 p.m. and 7 p.m.: A Concourse (Gate A12), Transit to International Arrivals Hall (Baggage claim 22), and the lower level baggage claim exit at the south end of the main terminal. If your family members were in these areas, watch for symptoms until Jan. 26.
Measles is finding a foothold in Washington state and local health officials announced the number of cases meets the definition of an outbreak in Snohomish County.
The Snohomish County Health Department confirmed three new measles cases this week, all in local children who were exposed to a contagious family visiting from South Carolina. The children tested positive on Wednesday, Jan. 14, after developing fever, cough and the telltale rash associated with measles. None of the children had been vaccinated.
Because the illness spread from person to person within the community, county officials say the cases officially constitute an outbreak — a sign that measles is circulating locally.
How this outbreak began
Health officials in Snohomish County and Public Health – Seattle & King County were first alerted last week that three members of a South Carolina family — one adult and two children — were infectious while visiting the region between Dec. 27, 2025, and Jan. 1, 2026. There have been 434 cases of measles have been reported since OctobeThe largest active measles outbreak in the U.S. is in South Carolina, where 434 cases of measles have been reported in South Carolina since October, making that state the largest outbreak in the country.
Before receiving a diagnosis, the family visited multiple public places in Everett, Marysville and Mukilteo, traveled through Seattle-Tacoma International Airport, and stopped at a nearby car rental facility — all while contagious.
Now, local officials say additional cases are likely.
“We’re expecting more measles cases as a result of the previous exposures as well as these new outbreak cases,” said Snohomish County Health Officer Dr. James Lewis. “We are hoping to contain it, but unfortunately there have been a number of exposure sites already, and there are likely more cases in the community that we do not know about yet.”
Lewis consulted with the Washington State Department of Health before declaring the outbreak. Under public health guidelines, an outbreak is defined as three or more linked measles cases in a community.
What families should know right now
Health officials emphasize that most people in the region are protected thanks to widespread vaccination.They note:
- Most residents have immunity through the MMR vaccine (measles, mumps and rubella)
- The vaccine is safe, highly effective, and provides about 97% lifetime protection
- The overall risk to the general public remains low
Families are urged to check vaccination records for all household members. If you or your children are not vaccinated — or if you’re unsure — officials strongly recommend getting vaccinated as soon as possible.
Public locations where exposure may have occurred
Measles can spread before symptoms appear and can linger in the air for up to two hours after an infected person leaves a space. Anyone who was at the following locations during the listed times may have been exposed:
- Jan. 8, 2026, 9:30 a.m. – 12:30 p.m.
Stellar Kids Dentistry Everett, 111 SE Everett Mall Way, Everett
- Jan. 9, 2026, 8:30 a.m. – 5:15 p.m.
Pathfinder Kindergarten Center (Mukilteo School District), 11401 Beverly Park Rd., Everett
- Jan. 9, 2026, 8:30 a.m. – 5:15 p.m.
Serene Lake Elementary School (Mukilteo School District), 4709 Picnic Point Rd., Edmonds
- Jan. 13, 2026, 1:10 p.m. – 3:10 p.m.
Swedish Mill Creek Campus, 13020 Meridian Ave. S., Everett
For additional exposure sites connected to the visiting South Carolina family, families are encouraged to review the Jan. 8 media release and the state Department of Health’s measles exposure map.
Another case in Central Washington
In a separate announcement this week, Kittitas County Public Health confirmed a measles case involving a Central Washington University student.
Anyone unvaccinated who was at the following locations should contact the Kittitas County Public Health call center at 509-933-8301:
January 8
- 8:30 a.m. – 2 p.m.: CWU Dining Lion Rock station, SURC
- 3 – 8:30 p.m.: CWU Dining Lion Rock station, SURC
- 1 – 4:50 p.m.: International Aviation Management, Samuelson Building
January 9
- 12:08 – 2:08 p.m.: CWU flight training center
- 2:30 – 4:30 p.m.: CWU flight training center
What to do if you may have been exposed
- Check whether you have received the recommended MMR vaccinations or had measles previously
- If symptoms develop — especially fever or rash — call a healthcare provider before visiting a clinic or hospital
- Limit contact with others, particularly infants and people with weakened immune systems
Why measles is taken so seriously
Measles is one of the most contagious diseases known. If one person has it, up to 9 out of 10 nearby people without immunity can become infected.
Symptoms include:
- Fever
- Rash
- Cough
- Runny nose
- Red, watery eyes
The incubation period ranges from 7 to 21 days, meaning symptoms may not appear until weeks after exposure. People are contagious before the rash appears, which makes outbreaks difficult to contain.
While many recover, measles can lead to ear infections, pneumonia, diarrhea, and in rare cases, brain swelling or death. The risk of complications is highest for:
- Infants and young children
- Adults over 20
- Pregnant people
- Individuals with compromised immune systems
“We’re concerned about the health and safety of our Snohomish County children,” said Kim Van Pelt, director of the Snohomish County Health Department. “Measles is a serious disease that often brings unpleasant symptoms, and in rare cases swelling of the brain and even death.”
Families seeking more information, including travel guidance and vaccination resources, can visit the Snohomish County Health Department’s measles page.
For now, health officials say awareness, vaccination, and early action remain the most effective tools for protecting the community Go the health department’s measles page for updates.
