At least three children in Colorado are hospitalized with measles, a highly contagious virus that could possibly put those who recently traveled through the Denver International Airport at risk.

The three children, who were not identified, are currently hospitalized at Children’s Hospital Colorado after contracting the disease while visiting another country with an “ongoing measles outbreak,” as per a statement from the Tri-County Health Department, which serves Adams, Arapahoe, and Douglas counties. Officials did not say which country the children had traveled to.

The children, who are related, according to The Denver Post, had not received the measles, mumps, and rubella (MMR) vaccine prior to falling ill.

Those who traveled to the Denver International Airport on Dec. 11 between 1:15 p.m. until 5:45 p.m. could be at risk of contracting the disease, especially if they have not received the MMR vaccine. Those who were at the Children's Hospital Colorado’s Anschutz Campus Emergency Department between 1 p.m. until 7:30 p.m. on Dec. 12 may also be at risk.

Though it’s unclear how many people may have been exposed, some 179,000 people traveled through the airport on Dec. 11, The Denver Post reported. 

“All individuals traveling on the plane with these children or who visited Children’s Colorado during this time frame and are believed to be at risk are being contacted directly by public health,” officials said in the news release, adding, “However; anyone who visited these locations at these times should monitor themselves or their children for symptoms of measles.” Read more at FOX News