This is a multi center study that includes the National Pediatric Hospital in Hanoi and the two major pediatric hospitals in Ho Chi Minh City. A study population of 520 HIV+ children receiving ARTs will be recruited from these hospitals. The reason for selecting children on ART is to see if treatment support can be initiated successfully after initiation of ART. Each HIV+ patient is examined according to WHO guidelines. HIV+ children will receive a complete physical examination including clinical staging of HIV infection, opportunistic infections and evidence of tuberculosis. Laboratory testing will include full blood count, CD4+ T-cell count (for children under five years of age CD4 %), viral load using ExaVirR viral load and liver enzymes. If indicated (e.g. prolonged cough and/or fever) chest X-ray, sputum microscopy for AFB will be done.