[1] Univ Ryukyus, Div Mol Virol & Oncol, Grad Sch Med, Okinawa 9030215, Japan
[2] Univ Ryukyus, Div Control & Prevent Infect Dis, Grad Sch Med, Okinawa 9030215, Japan
[3] Univ Ryukyus, Transdisciplinary Res Org Subtrop & Isl Studies, Okinawa 9030215, Japan
[4] Nagoya Univ, Dept Mol Biol, Grad Sch Sci, Chikusa Ku, Nagoya, Aichi 4648602, Japan
[5] Kanazawa Univ, Div Mol Bioregulat, Canc Res Inst, Kanazawa, Ishikawa 9200934, Japan
[6] Univ Rochester, Med Ctr, Dept Microbiol & Immunol, Rochester, NY 14642 USA
[7] Robert Koch Inst, Project Grp Nosocomial Infect Elderly 26, D-13353 Berlin, Germany