Colorado on Friday confirmed its 15th measles case of the year, in a fully vaccinated adult from Boulder who several times may have exposed passengers riding on the Flatiron Flyer bus between downtown Denver and Boulder.
The infected person had recently traveled to Europe, which, like the United States, is experiencing a resurgence of measles cases. The person rode the Flatiron Flyer six times earlier this month, twice on June 3, twice on June 5 and twice on June 6, according to the Colorado Department of Public Health and Environment.
CDPHE also reported other exposure locations in Denver and Boulder:
| Location | Date/time | When symptoms may develop |
| Market Building, 1400 16th St., Denver, CO | June 3-6, 8 a.m. – 6:15 p.m. | Through June 27 |
| RTD Flatiron Flyer (Denver and Boulder), exposure possible for travelers in both directions of bus route, morning and evening | Tuesday, June 3, 6:45 – 9:35 a.m., 4:05 – 7:15 p.m. | Through June 24 |
| Little Finch Coffee Shop, 1490 16th St., Denver, CO | Wednesday, June 4, noon – 2:15 p.m. | Through June 25 |
| Whole Foods, 1701 Wewatta St., Denver, CO | Wednesday, June 4, noon – 2:30 p.m. | Through June 25 |
| RTD Flatiron Flyer (Denver and Boulder), exposure possible for travelers in both directions of bus route, morning and evening | Thursday, June 5, 6:45 – 9:35 a.m.4:05 – 7:15 p.m. | Through June 26 |
| Little Finch Coffee Shop 1490 16th St., Denver, CO | Thursday, June 5, noon – 2:15 p.m. | Through June 26 |
| RTD Flatiron Flyer (Denver and Boulder), exposure possible for travelers in both directions of bus route, morning and evening | Friday, June 6, 6:45 – 9:35 a.m., 4:05 – 7:15 p.m. | Through June 27 |
| Rosetta Hall, 1109 Walnut St., Boulder, CO | Friday, June 6, 7:30 – 10:45 p.m. | Through June 27 |
As outbreaks explode across the country, this year has seen more measles cases in Colorado than all other years in the previous decade. But there is still no evidence of sustained transmission occurring in Colorado. Instead, most cases reported this year have involved people whose infections are believed to be related to travel.
Still, anyone who has been exposed to measles — commonly described as the most contagious human virus in existence — can develop symptoms. People who are unvaccinated are most at risk, but it is still possible, though unlikely, that those who have been vaccinated could become sick as well. Vaccinated individuals who do contract measles generally have less-severe illness and are less likely to spread the disease to others.
Measles often starts with general cold-like or allergy-like symptoms: Fever, cough, runny nose and/or red eyes. The telltale rash comes a few days later.
People who believe they may have been exposed to measles and who develop symptoms should call ahead — either to their doctor, their preferred clinic or to their local public health department — before seeking treatment, to avoid potentially exposing others. CDPHE maintains an updating list of dates and places where people may have been exposed to measles.