The total study duration is expected to be 4 years (3 years for enrolment and at least one year of follow-up) in five study sites: (1) Khmero-Soviet Friendship Hospital, Phnom Penh; (2) Calmette Hospital, Phnom Penh; (3) Provincial hospital, Svay Rieng province; and (4) Provincial hospital, Takeo province, (5) Provincial Hospital, Siem Reap.