Health officials confirm a second measles case in Mesa County and a possible measles exposure at Denver International Airport in an out-of-state traveler.

On Monday, the Colorado Department of Public Health and Environment (CDPHE) shared a list of measles exposure locations in Mesa County and Denver.

Of Colorado’s 21 cases, more than one has been reported in Arapahoe, Adams, Denver, El Paso and Mesa counties. Two-thirds were unvaccinated people or those whose status was unknown. Four cases have been in kids younger than 4, the rest have been in adults. The state reports five people have been hospitalized; no one has died.