[1] Univ Hosp Bonn, Dept Med 1, Bonn, Germany
[2] UCL Royal Free & Univ Coll Med Sch, Royal Free Ctr HIV Med, London, England
[3] UCL Royal Free & Univ Coll Med Sch, Dept Primary Care & Populat Sci, London, England
[4] Hosp Carlos 3, Infect Dis Serv, Madrid, Spain
[5] Hosp Carlos 3, Hepatol Unit, Madrid, Spain
[6] Univ Autonoma Barcelona, Hosp Germans Trias & Pujol, HIV Clin Unit, Badalona, Spain
[7] Univ Autonoma Barcelona, Hosp Germans Trias & Pujol, IrsiCaixa Retrovirol Lab, Badalona, Spain
[8] Hosp Jose Maria Ramos Mejia, Buenos Aires, DF, Argentina
[9] Centrum Diagnost & Terapii AIDS, Warsaw, Poland
[10] Hvidovre Univ Hosp, EuroSIDA Coordinating Ctr, Copenhagen HIV Programme, Copenhagen, Denmark
[11] Univ Zurich Hosp, CH-8091 Zurich, Switzerland