[1] Univ Basel, Inst Clin Epidemiol & Biostat, Dept Clin Res, Basel, Switzerland
[2] Univ Basel, Univ Hosp, Basel, Switzerland
[3] Univ Hosp, Div Infect Dis, Basel, Switzerland
[4] Univ Hosp, Hosp Epidemiol, Basel, Switzerland
[5] Univ Basel, Basel, Switzerland
[6] EYE T Serv, Freiburg, Germany
[7] Univ Liverpool, Dept Pharmacol, Liverpool, Merseyside, England
[8] Univ Zurich, Univ Hosp, Div Infect Dis, Zurich, Switzerland
[9] Univ Zurich, Univ Hosp, Hosp Epidemiol, Zurich, Switzerland
[10] Univ Zurich, Inst Med Virol, Zurich, Switzerland
[11] Univ Hosp Lausanne, Div Infect Dis, Lausanne, Switzerland
[12] Univ Hosp Bern, Div Infect Dis, Bern, Switzerland
[13] Univ Hosp Geneva, Div Infect Dis, Geneva, Switzerland
[14] Canton Hosp St Gallen, Div Infect Dis, St Gallen, Switzerland
[15] Canton Hosp St Gallen, Hosp Epidemiol, St Gallen, Switzerland
[16] Osped Regionale Bellinzona & Valli, Bellinzona, Switzerland
[17] Serv Madrileno Salud SERMAS, Subdirecc Gen Farm & Prod Sanitarios, Madrid, Spain
[18] Hosp Gen Univ Gregorio Maranon IiSGM, Madrid, Spain