Two confirmed cases of measles in Hawaii were in unvaccinated children who traveled to the Big Island from Washington state, a top Hawaii public health official said Monday.

Dr. Sarah Park, state epidemiologist for Hawaii, said Washington public health officials told her office that the family had been exposed to measles as part of the ongoing Clark County outbreak.

She said public health officials went to see the family and advised them to remain in the home where they were staying unless they could show proof of vaccination. Park said the home was on a large and relatively isolated part of the Big Island. She said state officials continued to keep tabs on the family during their stay.

“Basically we would check in with them and just make sure they were adhering to quarantine,” Park said.

During their visit this month, two children in the family developed measles. The condition was confirmed with lab tests performed by the state of Hawaii.

The family remained quarantined during the illness. People with measles are contagious four days before and four days after the onset of the rash that comes with the illness. The family was allowed to leave Hawaii five days after onset.

“They are gone, thankfully,” Park said.

Washington Gov. Jay Inslee declared a state of emergency due to the outbreak on Friday, three days after officials in Clark County declared a public health emergency. The outbreak spread to Oregon on Friday, with one confirmed measles case in Multnomah County.

Park said Washington public health officials notified Hawaiian authorities “fairly quickly” upon the family’s arrival that they had been exposed to someone with a documented case of measles in Washington.

“They really didn’t have a chance to go much of anywhere” on the island, Park said.

She said given the timing of the onset of the disease, the children weren’t contagious while in transit. They weren’t in an infectious period until a couple of days after they arrived in Hawaii, she said. She declined to provide their ages.

“We did notify our airport but based on the history and when the two developed the rash and counting back the infectious period four days before and four days after, the two that got measles were not infectious when in the airport,” Park said.

-- Noelle Crombie

503-276-7184

ncrombie@oregonian.com

@noellecrombie

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