SEATTLE (CN) – Washington state Gov. Jay Inslee declared a state of emergency Friday in response to a measles outbreak that has affected at least 31 people.

The outbreak started last week in the Portland, Oregon, suburb Clark County, Washington state, with 14 children confirmed infected.

A new count Tuesday showed adults with symptoms and a new case in the Seattle area.

“Measles is a highly contagious infectious disease that can be fatal in small children.” Inslee stated in his proclamation.

He said the disease “creates an extreme public health risk that may quickly spread to other counties.”

More state money can now be used for health investigations, laboratory testing and assistance to affected areas because of the state of emergency declaration.

Clark County declared a local public health emergency on Jan. 18 due to the outbreak.

Officials warned residents that infected persons visited the Portland International Airport, a Portland Trail Blazers basketball game and other local shopping and community spaces.

Seven percent of children in Clark County were exempt from the measles vaccine required for kindergarten in the 2017-2018 school year.

Peter J. Hotez, a professor of pediatrics and dean of the National School of Tropical Medicine at Baylor College of Medicine in Houston, said the Portland area, including Clark County, is a “hot spot” for outbreaks due to lack of immunization for personal or religious reasons, the Post reported.

“Portland is a total train wreck when it comes to vaccine rates,” Hotez told the Washington Post.

Measles symptoms include fever, dry cough, runny nose and sore throat.

“Measles is a highly contagious disease and if you don’t have immunity, you can get it just by being in a room where a person with measles has been,” Dr. Jeff Duchin, Health Officer for Public Health-Seattle & King County, said in a statement.

Officials reported nine more suspected cases in Clark County on Thursday.