1. Research Center Faculty of Medicine Ramathibodi Hospital Mahidol University Bangkok 10400 Thailand
2. Pediatric Translational Research Unit Department of Pediatrics Faculty of Medicine Ramathibodi Hospital Mahidol University Bangkok 10400 Thailand
3. Faculty of Medicine Ramathibodi Hospital Mahidol University Bangkok 10400 Thailand
4. Division of Epidemiology Department of Environmental and Public Health Sciences University of Cincinnati College of Medicine Cincinnati OH 45267 USA
5. Division of Infectious Diseases Department of Pediatrics Cincinnati Children's Hospital Medical Center University of Cincinnati College of Medicine Cincinnati OH 45267 USA
6. Division of Hematology and Oncology Department of Pediatrics Faculty of Medicine Ramathibodi Hospital Mahidol University Bangkok 10400 Thailand