[1] Tochigi Prefectural Inst Publ Hlth, Utsunomiya, Tochigi 3291196, Japan
[2] Gunma Prefectural Inst Publ Hlth & Environm Sci, Maebashi, Gunma 3710052, Japan
[3] Kagawa Univ, Fac Med, Maternal Perinatal Ctr, Miki, Kagawa 7610793, Japan
[4] Yokohama City Univ, Grad Sch Med, Dept Mol Biodef Res, Kanazawa Ku, Yokohama, Kanagawa 2360004, Japan
[5] Aomori Prefectural Inst Publ Hlth & Environm, Aomori 0308566, Japan
[6] Kyorin Univ, Sch Med, Dept Resp Med, Mitaka, Tokyo 1818611, Japan
[7] Natl Inst Infect Dis, Influenza Virus Res Ctr, Musashimurayama, Tokyo 2080011, Japan
[8] Natl Inst Infect Dis, Infect Dis Surveillance Ctr, Musashimurayama, Tokyo 2080011, Japan
[9] Natl Inst Infect Dis, Pathogen Genom Ctr, Musashimurayama, Tokyo 2080011, Japan
[10] Tokyo Kasei Univ, Dept Nutr Sci, Itabashi Ku, Tokyo 1738602, Japan