An unvaccinated child under 11 returned with measles from a country experiencing an outbreak of the disease, Clark County Public Health officials said Wednesday.

The child passed through Portland International Airport on Nov. 14. Health officials did not say where the child had traveled.

The agency warned that people in Vancouver and Portland may have been exposed to the virus. If somebody was exposed to the measles and is susceptible to an infection, they might start showing symptoms between Nov. 18 and Dec. 9.

“This is an unfortunate reminder that measles is only a plane, car, bus or train ride away,” Clark County Public Health director Dr. Alan Melnick said in a statement.

These are the dates, times and locations that people may have been exposed:

Portland International Airport, Concourse E, north end of lower level, including restrooms and baggage claim, from 10:30 a.m. to noon Thursday, Nov. 14.

PeaceHealth Southwest Medical Center, 400 N.E. Mother Joseph Place, Vancouver, from 12:45 p.m. to 5:05 p.m. Thursday, Nov. 14.

Randall Children’s Hospital at Legacy Emanuel, 2801 N. Gantenbein Ave., Portland, from 11:50 p.m. Saturday, Nov. 16, to 4:25 a.m. Sunday, Nov. 17.

Health officials asked people who think they are infected to call their healthcare provider before going to the doctor or the hospital. Symptoms start with a fever, cough, runny nose and red eyes, Clark County health officials said. Those symptoms are then followed by a rash that usually starts on an infected person’s head and spreads to the rest of the body.

Oregon has had four measles cases between Oct. 1 and Nov. 14, at least three of them linked to travel through Portland International Airport.

The measles virus is very good at infecting people who are not vaccinated, lingering in the air for up to two hours after an infected person passes by and coughs or sneezes. It takes one to three weeks for symptoms to show, which is also when a person becomes contagious.

Measles kills about one out of every 1,000 infected people, according to the U.S. Centers for Disease Control and Prevention. The disease is almost entirely preventable with two shots of a vaccine.

The New York Times reported Monday that a measles epidemic has sickened more than 1,000 people in Samoa, which has an immunization rate as low as 30%. The outbreak’s killed at least 16 people. Most of the fatalities involved children younger than 2, including a 7-month-old infant.

Vaccines are safe, the CDC says, though mild side effects are to be expected. Those include a slight fever or pain and redness where the person was injected. It takes at most a few days for the unpleasant side effects to go away, the CDC says.

People are supposed to get two doses of the vaccine. Per the CDC, one shot is 93 percent effective in protecting them from the virus, and two shots are 97 percent effective. Most people who do get sick did not get vaccinated, the CDC says.

Infants, pregnant women and people with weakened immune systems who were possibly exposed can get a shot of immunoglobulin, a medicine made from donor plasma that carries antibodies to infections like measles. But the shot is only good for six days after exposure -- and that sixth day is Friday.

Clark County had one of the worst measles outbreaks in the country earlier this year, according to federal data. Out of 86 cases in Washington, 71 were in Clark County. The entire state of California had 68 cases. The county health department ended up home-quarantining 849 children, health officials said. Combined, the outbreaks nationwide made for the worst measles season since 1992, federal health officials said.

Washington passed a bill eliminating personal or philosophical exemptions to vaccines earlier this year. The new law left the religious exemption on the books. Oregon tried to do something similar, but Democrats ended up nixing a vaccine exemption bill in order to get Republican support on other priority legislation.

-- Fedor Zarkhin

fzarkhin@oregonian.com

desk: 503-294-7674|cell: 971-373-2905|@fedorzarkhin

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