The Washington State Department of Health is announcing four newly diagnosed cases of measles in residents of three western Washington counties (King County 2, Snohomish County 1, Pierce County 1). These new cases are in addition to the case Tacoma-Pierce County Health Department announced Sunday.

While the exact exposure information for the new cases is not yet known, all spent time in SeaTac airport during their likely time of exposure or infectiousness. Find more details on places the new cases visited when they were infectious at Public Health — Seattle & King County, Tacoma-Pierce County Health Department and Snohomish Health District websites. Each local health agency will add new information about dates and locations of potential exposure to measles as each local investigation proceeds.

The Washington State Department of Health is supporting local public health agencies with disease investigation, laboratory testing and other efforts to protect their communities.

A current statewide case count for measles is on the department’s website and will be updated as new cases are diagnosed.

Measles is highly contagious and can be serious. Measles is easily spread when an infected person breathes, coughs, or sneezes. Almost everyone who has not had the vaccine or measles previously will get measles if they are exposed to the measles virus.

The department urges everyone to check their own and their children’s immunization records to verify that they’re fully immunized. You can check your immunization status through the DOH website.