1. Graduate School of Infection Control Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan
2. Kitasato Institute for Life Sciences (Present: Ōmura Satoshi Memorial Institute), Kitasato University, Tokyo 108-8641, Japan
3. Kitasato University School of Medicine, 1-15-1 Kitasato, Minami-ku, Sagamihara, Kanagawa 252-0374, Japan