[1] Penn State Univ, Milton S Hershey Med Ctr, Dept Pathol, Hershey, PA 17033 USA
[2] Univ Zagreb, Univ Hosp Infect Dis, Zagreb, Croatia
[3] Med Acad Latvia, Childrens Hosp, Riga, Latvia
[4] Sera & Vaccine Lab, Warsaw, Poland
[5] St Cyril & Method Hosp, Bratislava, Slovakia
[6] Case Western Reserve Univ, Cleveland, OH 44106 USA
[7] Univ Ljubljana, Ljubljana, Slovenia
[8] Natl Ctr Epidemiol, Budapest, Hungary
[9] Kaunas Med Univ Hosp, Kaunas, Lithuania
[10] Inst Cantacuzino, Bucharest, Romania
[11] Acad Med Sofia, Hosp Infect Dis, Sofia, Bulgaria
[12] Natl Canc Inst, Bratislava, Slovakia
[13] Natl Antibiot Reference Lab, Prague, Czech Republic