Affiliation: | Author affiliations: National Institute of Infectious Diseases, Tokyo, Japan (T.-C. Li, Y. Ami, Y. Suzaki, W. Takaji); ;Graduate School of Medicine, Hokkaido University, Sapporo, Japan (S.P. Yasuda, K. Yoshimatsu, J. Arikawa); ;Osaka University, Osaka, Japan (N. Takeda) |