Petty Officer 3rd Class Sarah Johnson, corpsman, Marine Medium Helicopter Squadron 364 (Rein.), 15th Marine Expeditionary Unit, prepares to vaccinate Lance Cpl. Christopher M. Carino, an airframe mechanic from the same unit, during the three-week Composite Training Unit Exercise, July 19. Corpsmen from the 15th MEU and the Peleliu Amphibious Ready Group began working together in the USS Peleliu’s medical center to ensure servicemembers were medically ready for deployment later this year.