Dr. Sam Sophan, served as vice chief of the department HIV/AIDS-TB of the National Pediatric Hospital (NPH), Phnom Penh, Cambodia where he began working in 1993. Sophan joined CHC in 2009 as the principle investigator of the its study to measure the prevalence of M. tuberculosis in children less than five years of age in Cambodia and to determine the best diagnostic approaches for TB in children. In 2002, Sophan spent 3 month at Brown University under the its Fogarty AIDS Training and Research Program where he designed an observational study on modified directly observe therapy for HAART in HIV infected children (MDOT-HAART) at NPH, the first of its kind in Cambodia.