1. Division of Global Epidemiology, International Institute for Zoonosis Control, Hokkaido University, Sapporo, Japan
2. Division of Molecular Pathobiology, International Institute for Zoonosis Control, Hokkaido University, Sapporo, Japan
3. Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rocky Mountain Laboratories, Hamilton, Montana, USA
4. Department of Oral and Maxillofacial Surgery, Hokkaido University Graduate School of Dental Medicine, Sapporo, Japan
5. Department of Respiratory Medicine, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
6. Department of Respiratory Medicine, National Hospital Organization Hokkaido Medical Center, Sapporo, Japan
7. International Collaboration Unit, International Institute for Zoonosis Control, Hokkaido University, Sapporo, Japan