The child, who remains hospitalized, had recently traveled with family to Chihuahua, Mexico, where there is an ongoing measles outbreak.

ADAMS COUNTY, Colo. — The Colorado Department of Public Health and Environment (CDPHE) and the Adams County Health Department have confirmed a case of measles in an unvaccinated child under 5 years old.

The child visited the Children’s Hospital Colorado emergency department in Aurora on Tuesday evening, and the virus could have infected people who passed through between 6:36 p.m. and 10:16