1. Division of Epidemiology, Department of Disease Control, Ministry of Public Health, Nonthaburi 11000, Thailand
2. Vaccine Preventable Diseases Unit, Division of Communicable Diseases, Department of Disease Control, Ministry of Public Health, Nonthaburi 11000, Thailand
3. Deputy Director General of the Department of Disease Control, Ministry of Public Health, Nonthaburi 11000, Thailand
4. Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA 30329, USA