1. Departments of Pediatric Infectious Diseases and
2. Departments of Tropical Pediatric Infectious Diseases,
3. Department of Pediatrics, Nagasaki University Hospital, Nagasaki, Japan;
4. Pediatrics, and
5. Department of Pediatrics, Khanh Hoa General Hospital, Nha Trang, Vietnam;
6. Clinical Medicine, Institute of Tropical Medicine, and
7. Clinical Medicine, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan;
8. Department of Bacteriology, National Institute of Hygiene and Epidemiology, Hanoi, Vietnam; and
9. Department of Planning and Research Collaboration, Khanh Hoa Health Service, Nha Trang, Vietnam