Dr. Koo earned a medical degree from the University of Texas Medical School at Houston and a master's degree in public health from the University of Texas School of Public Health in Houston. His training includes an internal medicine residency at the University of Texas Southwestern Medical Center in Dallas and an infectious diseases fellowship at BCM. Dr. Koo's volunteer service includes participation in medical mission trips to underprivileged communities in China, Mexico and Uganda. He specializes in food borne and diarrheal illnesses, and diseases primarily found in tropical and subtropical climates.