OLYMPIA — Gov. Jay Inslee has declared a state of emergency in all counties after more than two dozen cases of measles were confirmed, none on the North Olympic Peninsula.

“Measles is a highly contagious infectious disease that can be fatal in small children,” Inslee said in the proclamation issued Friday, saying that the confirmed cases in Clark County and King County create “an extreme public health risk that may quickly spread to other counties.”

As of Saturday, 31 cases had been confirmed in Clark County and one was confirmed in King County. One new case was confirmed in Multnomah County, which is home to Portland, Ore.

Public health officers in Clallam and Jefferson counties said Friday there were no suspected measles cases or known measles exposures among the North Olympic Peninsula population.

“We did send a message to all health care providers to plan for possible cases in our area,” said Dr. Allison Unthank, Clallam County health officer.

Given the number of public exposures that occurred in Clark County and the fact that a new case was confirmed in King County, Jefferson County Health Officer Dr. Tom Locke said more cases are expected.

“And they could be anywhere,” Locke said.

An outbreak in 2015 in Clallam County saw five people sickened who recovered and one who died of complications of the disease.

Measles is easily spread when an infected person breathes, coughs or sneezes. Complications of measles can include pneumonia, brain damage, deafness and death, especially in children.

And almost everyone who is not immune will get measles if exposed to the measles virus.

Unthank encouraged the public to make sure their measles vaccinations are current and to have their children vaccinated.

“Many people aren’t vaccinated,” Unthank said.

“Even one dose protects you 93 percent of the time.”

Measles vaccinations are available at many health care clinics and pharmacies on the Peninsula.

People born before 1957 are presumed to be immune from measles because the virus was common, Locke said.

Adults born in 1957 or later should have at least one measles shot, he said.

For children, adolescents, college students and health care professionals, the standard is two measles vaccinations, Locke said.

“For people who are non-immunized or under-immunized, now’s the time to change that,” Locke said.

“This is especially true with children who are not immunized.”

Most of the measles cases in the current outbreak involve children, Locke said.

Those who may have been exposed to measles or who are showing measles symptoms are urged to call their health care provider in advance.

Symptoms include a cough, high fever, red eyes and a rash that spreads throughout the body, Unthank said.

“It’s best to call ahead,” Locke said.

“The clinic will make sure you’re tested, but that it’s done in a way that is safe for everyone else in the clinic.”

The governor’s proclamation directs state agencies and departments to use state resources and do everything reasonably possible to assist affected areas.

A proclamation also is needed to request additional medical resources from other states.

A statewide case count for the measles outbreak will be updated daily on the Department of Health’s website at www.doh.wa.gov/.