1. Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
2. Department of Microbiology and Infectious Diseases, Nara Medical University, Kashihara, Nara, Japan
3. Division of Otolaryngology, Tohoku Medical and Pharmaceutical University, Sendai, Miyagi, Japan
4. Division of Cardiovascular Surgery, Tohoku Medical and Pharmaceutical University, Sendai, Miyagi, Japan
5. Division of Cardiovascular Surgery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
6. Department of Infectious Diseases, Internal Medicine, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
7. Division of Infectious Diseases and Infection Control, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, Sendai, Miyagi, Japan