A Boulder County resident who recently traveled to Europe has exposed RTD bus passengers to measles, health officials warned Friday.

The Colorado Department of Public Health and Environment, Boulder County Public Health and the Denver Department of Public Health and Environment confirmed the case, saying the adult who traveled to Europe was fully vaccinated.

The possible exposures occurred on the RTD Flatiron Flyer between Denver and Boulder in the morning and evening commutes on June 3, 5 and 6. Officials warn that exposure is possible for travelers in both directions of the bus route.

In addition, people could have also been exposed at:

Market Building, 1400 16th St. in Denver between June 3-6 from 8 a.m. to 6:15 p.m.

Little Finch Coffee Shop, 1490 16th St. in Denver on June 4 and 5 between noon and 2:15 p.m.

Whole Foods, 1701 Wewatta St. in Denver in June 4 between noon and 2:30 p.m.

Rosetta Hall, 1109 Walnut St. in Boulder on June 6 between 7:30 and 10:45 p.m.

Individuals who were possibly exposed should monitor for symptoms for 21 days from the date of exposure and consider avoiding public gatherings or high-risk settings, health officials said.

Symptoms include fever, cough, runny nose, red eyes, and a rash that starts several days later on the face and spreads, health officials said.

“The measles, mumps, and rubella (MMR) vaccine provides strong protection,” the CDPHE said. “Breakthrough cases typically experience milder illness and are less likely to spread the virus to others.”

Health officials said if you’ve been exposed at any of these locations and develop symptoms, contact your health care provider or urgent care center by phone immediately.

“Calling ahead helps prevent additional exposures,” the CDPHE said.