Passengers traveling though Dulles International Airport last Tuesday may have been exposed to the measles virus, according to the CDC. The scare comes after a 27-year-old woman flying from the United Kingdom to airports in D.C., Denver and Albuquerque tested positive for the virus. The CDC is currently in the in the process of tracking down anyone at risk of exposure and has provided local officials with information to begin tracing passengers on those flights. The Colorado Department of Public Health and Environment has already released an alert for travelers and workers in concourse C of Denver International Airport to be on the look out for early symptoms, such as the tell-tale rash, which can take up to 18 days to develop. Expect similar warnings, beyond those on the same passenger plane, for those having traveled through Dulles this past week. A similar warning was for those traveling through Reagan National Airport last October.