[1] Stanford Univ, Div Infect Dis, Stanford, CA 94305 USA
[2] Stanford Univ, Ctr AIDS Res, Stanford, CA 94305 USA
[3] Stanford Univ, Dept Stat, Stanford, CA 94305 USA
[4] Stanford Univ, Div Biostat, Stanford, CA 94305 USA
[5] Hosp Egas Moniz, Lisbon, Portugal
[6] BC Ctr Excellence HIV AIDS, Vancouver, BC, Canada
[7] Hlth Protect Agcy, Porton Down, England
[8] St Marys Hosp, Imperial Coll, Wright Fleming Inst, London, England
[9] Chulalongkorn Univ, Bangkok, Thailand
[10] Univ Fed Rio de Janeiro, Rio De Janeiro, Brazil
[11] Rega Inst, Louvain, Belgium
[12] Natl Inst Communicable Dis, Johannesburg, South Africa
[13] Publ Hlth Labs, Minist Hlth, Tel Hashomer, Israel
[14] Inst Adolfo Lutz Registro, Sao Paulo, Brazil
[15] Hosp Carlos III, Madrid, Spain
[16] Natl Inst Infect Dis, Tokyo, Japan
[17] Fdn Huesped, Buenos Aires, DF, Argentina
[18] UCL, London, England
[19] Hlth Protect Agcy, London, England