[1] Burnet Inst, Ctr Virol, Melbourne, Vic, Australia
[2] Monash Univ, Dept Med, Melbourne, Vic 3004, Australia
[3] Aarhus Univ, Dept Med Microbiol & Immunol, DK-8000 Aarhus C, Denmark
[4] Pfizer Global Res & Dev, Sandwich, Kent, England
[5] Univ Calif Los Angeles, David Geffen Sch Med, Dept Microbiol Immunol & Mol Genet, Los Angeles, CA 90095 USA
[6] Alfred Hosp, Infect Dis Unit, Melbourne, Vic, Australia
[7] Monash Univ, Dept Microbiol, Melbourne, Vic 3004, Australia
[8] Univ Melbourne, Dept Microbiol & Immunol, Parkville, Vic 3052, Australia