[1] Papageorgiou Gen Hosp, Intens Care Unit, Thessaloniki, Greece
[2] Papageorgiou Gen Hosp, Dept Microbiol, Thessaloniki, Greece
[3] Gennimatas Gen Hosp, Intens Care Unit, Thessaloniki, Greece
[4] Aristotle Univ Thessaloniki, Sch Med, Dept Hyg & Epidemiol, GR-54006 Thessaloniki, Greece
[5] Ippokratio Gen Hosp, Intens Care Unit, Thessaloniki, Greece
[6] Univ Hosp, Univ Intens Care Unit, Iraklion, Crete, Greece
[7] Univ Hosp, Univ Intens Care Unit, Ioannina, Greece