1. Epidemiology Unit, Faculty of Medicine, Prince of Songkla University, Hatyai, Songkhla, Thailand
2. Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan, USA
3. Division of Dermatology, Kumamoto Central Hospital, Kumamoto, Japan
4. The Office of Disease Prevention and Control Region 11, Nakhon Si Thammarat, Thailand