1. Kitasato University School of Allied Health Sciences, Sagamihara , Kanagawa , Japan
2. Yamazaki Gakuen University School of Animal Health Sciences, Hachiouji , Tokyo , Japan
3. Center for Natural Sciences, Kitasato University, Sagamihara , Kanagawa , Japan
4. Department of Internal Medicine, Shiki Community Hospital, Shiki , Saitama , Japan
5. Department of Infectious Diseases, Internal Medicine, University of Tokyo , Tokyo , Japan