UPDATE JAN. 18: Outbreak grows to 19 people, including one who attended Blazers game.

The number of unvaccinated Clark County children with confirmed cases of the measles continues to rise, officials said Thursday, as does the number of public and private businesses where people may have been exposed to the contagious children.

Public health officials have confirmed 16 Clark County-area children have the measles, and another five are suspected to have the preventable disease. Fourteen of the confirmed cases involve children who have not been vaccinated.

According to a news release, the remaining two cases involved children with unverified immunization histories. Two children have been hospitalized, one with a confirmed measles case and the other suspected.

Measles is a highly contagious viral illness spread through the air when an infected person coughs or sneezes. It was thought to be eradicated years after the vaccine hit the U.S. in 1963. Prior to the vaccine, 400 to 500 people would die every year, and 48,000 or more were hospitalized.

Clark County has one of the worst vaccination rates among all Washington counties, with just 77.4 percent of all public students having completed their vaccinations, according to state records.

Marissa Armstrong, Clark County Public Health spokeswoman, said investigators are still trying to pinpoint the main source of the outbreak. The office is withholding some sensitive information which may otherwise identify the families involved.

The infected children visited busy public spaces, like the Portland International Airport, and private businesses like Costco. The county released a list of two dozen locations Thursday where people may have been exposed to measles – ranging from schools, to a Vietnamese restaurant to a Portland hardware store.

“I don’t think anybody would be surprised,” Armstrong said, “if these numbers continue to grow.” She said measles is highly contagious and the children visited a variety of public spaces – including schools – in Oregon and Southwest Washington when they were highly contagious.

Children are typically vaccinated against the measles starting between 12 and 15 months, with a second shot between ages 4 and 6.

Of the Clark County confirmed cases, 13 of the 16 involve children between the ages of 1 and 10.

Complications from measles can include ear infections or diarrhea, along with more severe health issues like pneumonia, encephalitis (brain swelling) or total hearing loss.

Additionally, measles is potentially harmful to pregnant woman, – who may suffer miscarriages or premature births– and it’s also particularly dangerous for people with compromised immune systems.

Officials ask anyone who has been exposed and believes they have measles symptoms to call their doctor before visiting a medical office to avoid exposing others.

Here’s a full list of the locations:

Public exposure locations

People who visited the following locations may have been exposed to measles:

Health care facilities:

PeaceHealth Urgent Care – Memorial, 3400 Main St., from noon to 5:30 pm Monday, Dec. 31.

Magnolia Family Clinic, 2207 NE Broadway, Suite 200, Portland from 11:30 am to 3 pm Tuesday, Jan. 8.

The Vancouver Clinic, 700 NE 87th Ave., Vancouver

3:30 to 7 pm Friday, Jan. 11.

10:45 am to 1:30 pm Saturday Jan. 12.

4:30 to 7:30 pm Sunday, Jan. 13.

9:30 am to 1 pm Monday, Jan. 14.

Kaiser Cascade Park, 12607 SE Mill Plain Blvd., Vancouver from 1 to 8:30 pm Saturday, Jan. 12.

Randall Children's Hospital at Legacy Emanuel Emergency Department, 2801 N Gantenbein Ave., Portland from 11:30 am to 2 pm Saturday, Jan. 12.

PeaceHealth Southwest Medical Center Emergency Department, 400 NE Mother Joseph Pl., Vancouver

10 pm Saturday, Jan. 12 to 4 am Sunday, Jan. 13.

12:30 to 8:30 pm Sunday, Jan. 13.

Legacy Salmon Creek Medical Center Emergency Department, 2211 NE 139th St., Vancouver

8:30 pm Saturday, Jan. 12 to 1 am Sunday, Jan. 13.

5:45 pm Sunday, Jan. 13 and 12:30 am Monday, Jan. 14.

11:40 pm Monday, Jan. 14 to 5:10 am Tuesday, Jan. 15.

Rose Urgent Care and Family Practice, 18 NW 20th Ave., Battle Ground from 3:45 to 8 pm Monday, Jan. 14.

Schools:

Cornerstone Christian Academy, 10818 NE 117th Ave., Vancouver on Friday, Jan. 4

Vancouver Home Connection, 301 S. Lieser Road, Vancouver on Monday, Jan. 7; Tuesday, Jan. 8; and Friday, Jan. 11.

Hearthwood Elementary School, 801 NE Hearthwood Blvd., Vancouver on Monday, Jan. 7; Tuesday, Jan. 8; and Wednesday, Jan. 9.

Image Elementary School, 4400 NE 122nd Ave., Vancouver on Tuesday, Jan. 8 and Wednesday, Jan. 9.

Eisenhower Elementary School, 9201 NW Ninth Ave., Vancouver on Tuesday, Jan. 8 and Wednesday, Jan. 9.

Tukes Valley Primary School, 20601 NE 167th Ave., Battle Ground on Tuesday, Jan. 8.​

Tukes Valley Middle School, 20601 NE 167th Ave., Battle Ground on Tuesday, Jan. 8

Public Health is requiring exclusion of students and staff without documented immunity to measles from the above schools, as well as child care and other congregate settings. Students and staff at schools where measles exposure did not occur are not impacted by exclusions.

Other locations:

Church of Christ Savior, 3612 F St., Vancouver from 9:30 am to noon Sunday, Jan. 6 and 6 to 11:30 pm Sunday, Jan. 6.

Church of Truth, 7250 NE 41st St., Vancouver from 11 am to 4:30 pm Sunday, Jan. 6.

Portland International Airport, 7000 NE Airport Way, Portland from 10:45 am to 3:45 pm on Monday, Jan. 7. More specifically, anyone who spent time in Concourse D and the Delta Sky Lounge during that time period.

Costco, 4849 NE 138th Ave., Portland from 1 to 5:30 pm Tuesday, Jan. 8.

Amazon Lockers, 1131 SW Jefferson St., Portland from 3:30 pm to 7 pm Thursday, Jan. 10.

Rejuvenation, 1100 SE Grand Ave. Portland from 3:30 to 7:30 pm Thursday, Jan. 10.

Pho Green Papaya, 13215 SE Mill Plain Blvd., Vancouver from 7:30 to 10:30 pm Thursday, Jan. 10.

Chuck's Produce, 13215 SE Mill Plain Blvd., Vancouver from 8 to 11:45 pm Thursday, Jan. 10 and 2:30 to 5:30 pm Friday, Jan. 11.

Ikea, 10280 NE Cascades Parkway, Portland from 4:30 to 8:30 pm Friday, Jan. 11.

-- Andrew Theen

atheen@oregonian.com

503-294-4026

@andrewtheen

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