Lt. Col. Natalie Riley, physician assistant with the 315th Aerospace Medicine Squadron, Briefs members of the 437th and 315th Airlift Wing about the new aircrew screening process March 23, 2020 at Joint Base Charleston, S.C. Aircrew members from both wings will now receive prevention education before each mission and will receive a COVID-19 medical screening upon return.   (U.S. Air Force photo / Lt. Col. Wayne Capps)