1. Department of Infection Control, Fukushima Medical University, Fukushima 960-1295, Japan
2. Laboratory Medicine and Infectious Disease, Department of Internal Medicine, Iwate Medical University, Yahaba 028-3695, Japan
3. Ikeda Memorial Hospital, Sukagawa 962-0001, Japan
4. Department of Clinical Laboratory Sciences, School of Health Sciences, Fukushima Medical University, Fukushima 960-8516, Japan
5. Department of Microbiology, Fukushima Prefectural Institute of Public Health, Fukushima 960-8560, Japan
6. Department of Social Health and Welfare, Fukushima Prefectural Government, Fukushima 960-8670, Japan