UPDATE JAN. 16: The number of confirmed cases is up to 14. All the victims are children.

Two unvaccinated children in the Vancouver area have confirmed cases of the measles, public health officials said Tuesday, and it’s unclear if the outbreak is connected to another case from earlier this month.

Clark County Public Health officials are investigating the two confirmed cases plus an additional 11 suspected cases, all among children in southwest Washington. The measles outbreak comes days after a separate Jan. 4 confirmed measles case in the Vancouver area. It’s unclear if the child in the Jan. 4 case was vaccinated, and officials also don’t know the vaccination status of the 11 suspected cases.

Dr. Alan Melnick, public health director and health officer for the county, said there are likely more measles cases out there, and the county is waiting for test results on the 11 suspected cases to come back.

Melnick said the outbreak is occurring even though measles is “completely and entirely preventable” with vaccines.

“Measles was considered eradicated,” Melnick said in an interview. “We’re obviously seeing more cases more recently,” he added, as some parents opt not to vaccinate their children against the disease.

According to Washington state records, just 77.4 percent of all Clark County public students last year had completed all of their vaccinations, the sixth worst among all counties in the state. Some 6,218 students had a recorded exemption – either for religious, personal or medical reasons –from completing their vaccinations.

Melnick said before the measles vaccine hit the U.S. in 1963, 400 to 500 people would die from the disease every year, and 48,000 more were hospitalized. “It can be a very deadly disease.”

Melnick said the recent outbreak is scary, and he notes that schools need “well over 90 percent” of students to be vaccinated to achieve herd immunity. “Once you get below that, it can spread like wildfire,” he said.

Children are typically vaccinated twice, once from 12 to 15 months and a second dose between the ages of 4 and 6. Those two doses are 97 percent effective in preventing disease contraction, according to the Centers for Disease Control and Prevention.

Washington health officers are warning people who visited the following public locations that they could have been exposed to measles:

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

Portland International Airport, from 10:45 am to 3:45 pm Monday, Jan. 7. Specifically, anyone who was in Concourse D and the Delta Sky Lounge during that time.

Melnick said measles’ incubation period is anywhere from seven to 21 days, and that symptoms will likely pop up in that timeframe.

“Don’t go to the ER or doctor,” Melnick said, unless people are in a life-threatening situation. “Call first. You can infect other people in the emergency room or the doctor’s office.”

Measles poses the greatest risk for infants 12 months and younger.

Measles sufferers will develop a fever, cough, runny nose and red eyes, Melnick said, then a rash originating from the head and spreading to the rest of your body.

But measles is contagious for four days before the rash appears and as long as four days after it appears, officials said. Complications can include ear infections or diarrhea, plus more severe health issues like pneumonia, encephalitis (brain swelling) or total hearing loss. Measles is dangerous for pregnant woman as well, and can lead to miscarriages, premature births or babies with low-birth-weights

Here are some number to call if you need more info:

Clark County Public Health, 564-397-8182

Multnomah County Public Health, 503-988-3406

Washington County Public Health, 503-846-3594

Clackamas County Public Health, 503-655-8411

-- Andrew Theen

atheen@oregonian.com

503-294-4026

@andrewtheen

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