[1] Univ New S Wales, Kirby Inst Infect & Immun Soc, Sydney, NSW 2052, Australia
[2] Univ Washington, Dept Stat, Seattle, WA 98195 USA
[3] Univ British Columbia, Dept Med, Div Infect Dis, Vancouver, BC, Canada
[4] St Pauls Hosp, British Columbia Ctr Excellence HIV AIDS, Vancouver, BC V6Z 1Y6, Canada
[5] British Columbia Ctr Dis Control, Vancouver, BC, Canada
[6] Univ Ottawa, Dept Med, Div Infect Dis, Ottawa, ON, Canada