[1] Univ Athens, Sch Med, Dept Hyg & Epidemiol, GR-11527 Athens, Goudi, Greece
[2] Laikon Gen Hosp, Reg Blood Transfus Ctr 2, Athens, Greece
[3] Blood Donat Ctr Thessaly, Larisa, Greece
[4] A Fleming Blood Transfus Ctr, Athens, Greece
[5] Univ Patras, Sch Med, Dept Internal Med, Div Hematol, GR-26110 Patras, Greece
[6] Hippokrateion Hosp, Athens, Greece
[7] Konstantopoulio Gen Hosp N Ionia, Athens, Greece
[8] Elpis Gen Hosp, Athens, Greece
[9] Univ Hosp, Blood Bank, Ioannina, Greece
[10] Gen Athens Hosp G Gennimatas, Reg Blood Transfus Ctr 3, Athens, Greece