180615-N-KR394-002 SAN DIEGO, Calif. (June 18, 2018) Command Master Chief Patrick Mangaran, left, leads hospital corpsmen from Naval Medical Center San Diego in an early morning formation run through Balboa Park in San Diego, Calif., June 15, 2018, in celebration of the Hospital Corps' 120th birthday. The Hospital Corps is the only enlisted corps in the Navy. (U.S. navy photo by Mike Alvarez/Released)