AURORA, Colo. (CBS4) — Last month, three children infected with measles visited Children’s Hospital Colorado for treatment. Their family flew into Denver International Airport earlier that week.

(credit: CBS)

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The children contracted the virus from another country and were all unvaccinated.

People who were at DIA and the hospital’s Emergency Department during the times of exposure were advised to keep an eye out for symptoms of measles in the following weeks.

Tri-County Health Department notified 258 individuals, who were at the hospital when the infected children were admitted, about their risk of exposure.

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The incubation period ended Friday.

Health officials told CBS4 there were no new confirmed cases of measles in the hospital’s exposure group, but a passenger on one of the children’s flights wasn’t as lucky.

“There was a secondary case of measles that developed from someone who was on an international flight with the cases,” said Dr. Bernadette Albanese at Tri-County Health. “That individual lives in another state, and we do not know the details.”

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Bernadette Albanese (credit: CBS)

Tri-County Health is only responsible for investigating measles exposure in Colorado.

Of the 258 people at Children’s Hospital who notified by Tri-County Health, 20 of them were considered susceptible to measles. They were either unvaccinated, couldn’t provide records of immunization, or were infants too young to receive vaccine.

“At least five were quarantined, and at least 12 received a medication called immunoglobulin,” Albanese said of those 20 people.

She says the best way to protect yourself and your community in the future is to get your MMR vaccination. Measles is among the most contagious viruses. About 90% of people who have never been immunized against measles become ill after exposure.

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“Vaccinated people prevent outbreaks. We have not experienced secondary cases, mostly because we’re vaccinated and protected. That’s the importance of vaccination,” said Albanese.

Colorado has the lowest MMR kindergarten vaccination rate in the country.

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People who have questions about this incident or who need general information about measles can call CO-Help at 303-389-1687 or 1-877-462-2911 for answers in English and Spanish. For more information about the measles, visit:

Tori Mason