[1] Univ Hosp Bern, Div Infect Dis, CH-3010 Bern, Switzerland
[2] Basel Inst Clin Epidemiol, Basel, Switzerland
[3] Univ Basel Hosp, Div Infect Dis, CH-4031 Basel, Switzerland
[4] Ctr Univ Hosp Vaudois, Lausanne, Switzerland
[5] Univ Zurich Hosp, CH-8091 Zurich, Switzerland
[6] Kantonsspital, St Gallen, Switzerland
[7] Univ Hosp Geneva, Geneva, Switzerland
[8] Hosp Civ Lugano, Lugano, Switzerland