1. The HIV Netherlands Australia Thailand Research Collaboration (HIV-NAT), The Thai Red Cross AIDS Research Centre, Bangkok, Thailand.
2. Khon Kaen University, Khon Kaen, Thailand.
3. Department of Pediatrics, Chulalongkorn University, Bangkok, Thailand.
4. Department of Medicine, Chulalongkorn University, Bangkok, Thailand.
5. SEARCH, The Thai Red Cross AIDS Research Centre, Bangkok, Thailand.