[1] Hlth Canada, Canadian Sci Ctr Human & Anim Hlth, Natl Microbiol Lab, Special Pathogens Program, Winnipeg, MB R3E 3R2, Canada
[2] USA, Med Res Inst Infect Dis, Dept Mol Virol, Div Virol, Frederick, MD 21702 USA
[3] Karolinska Inst, Stockholm Branch, Ludwig Inst Canc Res, SE-17177 Stockholm, Sweden
[4] Univ Manitoba, Dept Med Microbiol, Winnipeg, MB R3E 0W3, Canada