Maryland and Virginia health officials have released more information regarding the possible measles exposure to travelers moving through Reagan National Airport and Baltimore-Washington International Thurgood Marshall Airport. The first may have occurred on Feb. 20 at Dulles Airport in the International Arrivals and Baggage Claim level of the main terminal from 3:15 to 7:15 p.m. Authorities have also confirmed that the infected traveler then traveled through BWI airport on a 7 p.m. flight two days later. In addition to having contacted passengers on the flights, officials ask those in the area who develop symptoms to contact their doctors.