May 21 (UPI) -- Americans traveling back to the United States who have recently been in Democratic Republic of the Congo, Uganda or South Sudan will be required to enter the country through Washington, D.C. Citizens and lawful permanent residents who have been in any of the countries in the last 21 days will be required to fly to Washington Dulles International Airport for enhanced health screenings before continuing on to their final destination, the U.S. Department of State announced. The