1. Department of Internal Medicine, Miyazaki Prefectural Nobeoka Hospital, Japan
2. Department of Critical Care Medicine, Miyazaki Prefectural Nobeoka Hospital, Japan
3. Department of Pathology, Miyazaki Prefectural Nobeoka Hospital, Japan
4. Department of Virology I, National Institute of Infectious Disease, Japan
5. Department of Pathology, National Institute of Infectious Disease, Japan