1. Virology Laboratory, National Center for Communicable Diseases, Mongolia
2. Epidemiology, National Center for Communicable Diseases, Mongolia
3. National Center for Communicable Diseases, Mongolia
4. Department of Viral Diseases and Vaccine Control, National Institute of Infectious Diseases, Japan
5. Chiba Serum Institute, Japan
6. Department of Virology II, National Institute of Infectious Diseases, Japan
7. Department of Pediatrics, Toho University School of Medicine, Japan