[1] Geneva Univ Hosp, Serv Lab Med, Geneva, Switzerland
[2] Fac Med, Geneva, Switzerland
[3] Geneva Univ Hosp, Serv Infect Dis, Geneva, Switzerland
[4] Lausanne Univ Hosp, Inst Microbiol, Rue Bugnon 48, CH-1011 Lausanne, Switzerland
[5] Geneva Univ Hosp, Infect Control Programme, Geneva, Switzerland
[6] Lausanne Univ Hosp, Serv Hosp Prevent Med, Lausanne, Switzerland
[7] Geneva Univ Hosp, Intens Care Unit, Geneva, Switzerland
[8] Lausanne Univ Hosp, Dept Med, Infect Dis Serv, Lausanne, Switzerland