1. Department of Bacteriology I, National Institute of Infectious Diseases, Tokyo 162-8640, Japan
2. Department of Microbiology and Immunology, Nihon University of School of Dentistry at Matsudo, Matsudo 271-8587, Japan
3. Tokyo Metropolitan Institute of Public Health, Tokyo 169-0073, Japan
4. Department of Periodontology, Nihon University School of Dentistry at Matsudo, Matsudo 271-8587, Japan
5. National Center for Global Health and Medicine, Tokyo 162-8655, Japan
6. Department of Orthodontics, Nihon University School of Dentistry at Matsudo, Matsudo 271-8587, Japan