[1] Geneva Univ Hosp, Infect Control Program, Geneva, Switzerland
[2] Geneva Univ Hosp, WHO Collaborating Ctr, Geneva, Switzerland
[3] Fac Med, Geneva, Switzerland
[4] Univ Hosp Basel, Div Infect Dis & Hosp Epidemiol, Basel, Switzerland
[5] Univ Basel, Basel, Switzerland
[6] Univ Hosp Zurich, Dept Infect Dis & Hosp Epidemiol, Zurich, Switzerland
[7] Univ Zurich, Zurich, Switzerland
[8] Lausanne Univ Hosp, Serv Infect Dis, Infect Prevent & Control Unit, Lausanne, Switzerland
[9] Univ Bern, Bern Univ Hosp, Dept Infect Dis, Bern, Switzerland
[10] EOC Reg Hosp Lugano, Dept Infect Dis & Hosp Epidemiol, Lugano, Switzerland
[11] Swissnoso, Natl Ctr Infect Control, Bern, Switzerland
[12] Valais Hosp, Cent Inst, Div Infect Dis, Sion, Switzerland
[13] Univ Paris Cite, INSERM, IAME, UMR 1137, F-75018 Paris, France