[1] Univ Antwerp, Fac Med, Vaccine & Infect Dis Inst, Ctr Evaluat Vaccinat, B-2160 Antwerp, Belgium
[2] Ctr Dis Control & Prevent, Div Viral Hepatitis, Atlanta, GA USA
[3] WHO, Dept Immunizat Vaccines & Biol, CH-1211 Geneva, Switzerland
[4] Pan Amer Hlth Org, Washington, DC USA
[5] Hadassah Hebrew Univ Hosp, Liver Unit, Jerusalem, Israel