Second Lt. Kristina Valentic, a clinical nurse with the 910th Medical Squadron, administers a dose of influenza vaccine to an Airman at the 910th Logistics Readiness Squadron Deployment Center here, Nov. 5, 2016. U.S. Servicemembers are required to receive the vaccine annually to protect against influenze and help maintain the medical readiness of the force. (U.S. Air Force photo/Staff. Sgt. Rachel Kocin)