1. Department of Pediatric Infectious Diseases, Institute of Tropical Medicine, Nagasaki University, Nagasaki 852-8523, Japan
2. Khanh Hoa Health Service, Nha Trang 650000, Vietnam
3. Department of Ophthalmology, Nagasaki University Hospital, Nagasaki 852-8501, Japan
4. Khanh Hoa General Hospital, Nha Trang 650000, Vietnam
5. National Institute of Hygiene and Epidemiology, Hanoi 100000, Vietnam
6. Department of Virology, Institute of Tropical Medicine, Nagasaki University, Nagasaki 852-8523, Japan
7. Center for Vaccines and Therapeutic Antibodies for Emerging Infectious Diseases, Shimane University, Izumo 693-0021, Japan
8. Department of Pediatrics, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8501, Japan