The Colorado Department of Public Health and Environment has confirmed 14 cases of measles across the state. The majority of those are linked to an out-of-state traveler who flew while infectious and arrived at Denver International Airport last month.

The latest case is linked to the out-of-state traveler who was exposed at the airport on May 13. That person is described as an unvaccinated adult from Arapahoe County. 

The thirteenth case was reported to the CDPHE on June 9 as a child under the age of 5 from El Paso County and had traveled to Canada with family. 

The CDPHE said 2025 marks the highest increase and confirmation of reported measles cases in Colorado since 2014.

Officials said that the best protection is the measles, mumps, and rubella or MMR vaccine. They added that, in rare cases, people who have been vaccinated can still contract the measles, but their symptoms are milder and they are less likely to spread it to others. Anyone experiencing symptoms is encouraged to call their healthcare provider or hospital before visiting to avoid exposing others.