More Washington state measles exposures, including at Costco in Issaquah

King County public health officials have confirmed two more measles cases in Washington residents, and warned of other possible exposures to the infectious disease over the past two weeks, including at Costco in Issaquah and a couple of local swimming pools.

An adult and a child who live in the same household in King County tested positive after hosting an international visitor who reported being ill, according to Public Health - Seattle & King County. The cases are not connected to any of the previous measles infections identified this year, public health officials said, meaning the disease does not appear to be spreading within the community at this point.

The child had received one dose of the measles, mumps and rubella vaccine, the health department said. Health officials don't yet know whether the adult family member was vaccinated against measles. The international visitor, whose vaccination status was unclear Thursday, remains in King County.

The new infections bring the state's total to 10 among residents this year, though other cases have also been confirmed among people traveling through Washington, according to the public health department.

People who were at the following locations during these times, which includes the estimated time when the person was there and two hours after, might have been exposed to measles:

* June 14 from 11 a.m. to 2:30 p.m. — Bellevue Fire Station 9 (12412 Newcastle Way, Bellevue)

* June 15 from 10:30 a.m. to 2 p.m. — St. Madeleine Sophie Catholic Parish (4400 130th Place S.E., Bellevue)

* June 15 from 3 to 6 p.m. — Lake Union Swim Academy (2040 Westlake Ave. N., Seattle)

* June 18 from 1 to 4 p.m. — Mary Wayte Pool (8815 S.E. 40th St., Mercer Island)

* June 18 from 2:30 to 5:30 p.m. — Costco Issaquah (1801 10th Ave. N.W., Issaquah)

* June 19 from 1:20 to 4:20 p.m. — Overlake Clinics Newcastle Urgent Care (13159 Newcastle Commons Drive, Newcastle)

* June 20 from 11:50 a.m. to 5:45 p.m. — Seattle Children's hospital (4800 Sand Point Way N.E., Seattle)

* June 22 from 9:15 to 11:45 a.m. — Swedish First Hill hospital (747 Broadway, Seattle)

If you were at the locations at the times listed and are not immune to measles, the most likely time you would become sick would be between June 21 and July 13, public health officials said.

Those who were in the listed areas during times of potential exposure should find out whether they have received their MMR vaccine or had measles before, the health department said.

“With more measles cases globally and in the U.S., if you are planning to travel, make sure you’re up to date on all your vaccinations, Meagan Kay, medical epidemiologist for Public Health - Seattle & King County, said in a statement this week. "Vaccination will not only protect you but will also make you less likely to spread it to others if you develop measles."

Washington has recorded relatively few measles cases compared with other parts of the country, including Texas and New Mexico, which continue to battle major outbreaks. As of this week, more than 1,200 cases have been confirmed in the U.S. this year, spanning at least 36 states, according to the Centers for Disease Control and Prevention.

Vaccination rates are high in Western Washington, which has prevented the small number of local measles cases from spreading further in the community, the King County health department said. Still, there are clusters of underimmunization, the department said. For example, only 62% of Washington 4- to 6-year-olds were fully vaccinated last year.

The measles vaccine is effective, with two shots providing about 97% protection for a lifetime.

"The CDC now recommends that anyone traveling internationally ensure they’re fully vaccinated against measles prior to their trip," Kay added in the statement. "Make sure to get vaccinated at least two weeks before your trip. This gives your body a chance to build immunity.

If you develop a fever or unexplained rash, call a health care provider, but limit contact with others and do not go to a clinic or hospital without calling first, the health department said.

Measles is extremely contagious and can cause fever, rash, cough, runny nose and red, watery eyes. An infected person is infectious from about four days before the rash appears through four days after.

One person infected with measles can spread the virus to up to 9 out of 10 people nearby if they aren’t protected, the health department said.

For more information about measles, including where to get vaccinations, go to kingcounty.gov/measles.

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