1. Department of Internal Medicine, Ohta-Nishinouchi Hospital, Japan
2. Infection Control Unit, Ohta-Nishinouchi Hospital, Japan
3. Department of Infection Control, Fukushima Medical University, Japan
4. Department of Respiratory Medicine and Infectious Disease, Niigata University Graduate School of Medical and Dental Sciences, Japan
5. Microbiological Laboratory Unit, Ohta-Nishinouchi Hospital, Japan
6. Department of Emergency Medicine, Ohta-Nishinouchi Hospital, Japan