1. Department of Virology II, National Institute of Infectious Diseases, Gakuen 4-7-1, Musashi-murayama, Tokyo 208-0011, Japan
2. Division of Experimental Animals Research, National Institute of Infectious Diseases, Gakuen 4-7-1, Musashi-murayama, Tokyo 208-0011, Japan
3. Department of Environmental Parasitology, Tokyo Medical and Dental University, M&D Tower 16F, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan
4. Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0781, Japan