[1] Univ Basel, Dept Biomed, CH-4003 Basel, Switzerland
[2] Univ Basel Hosp, Div Infect Dis & Hosp Epidemiol, Basel, Switzerland
[3] Autonomous Univ Barcelona, Hosp Santa Creu & St Pau, Dept Hematol, Barcelona, Spain
[4] UCL, Div Infect & Immun, London WC1E 6BT, England
[5] Fred Hutchinson Canc Res Ctr, Vaccine & Infect Dis Div, Seattle, WA 98104 USA
[6] Univ Wurzburg, Dept Internal Med 2, D-97070 Wurzburg, Germany
[7] Karolinska Univ Hosp, Dept Hematol, Stockholm, Sweden
[8] Karolinska Inst, Dept Med Huddinge, Div Hematol, Stockholm, Sweden