[1] Univ Hosp Geneva, Infect Control Programme, Dept Internal Med, CH-1211 Geneva 14, Switzerland
[2] Univ Hosp Geneva, Med Clin 2, Dept Internal Med, CH-1211 Geneva 14, Switzerland
[3] Univ Hosp Geneva, Intens Care Unit, Dept Internal Med, CH-1211 Geneva 14, Switzerland
[4] Univ Hosp Geneva, Div Infect Dis, Dept Internal Med, CH-1211 Geneva 14, Switzerland