Lasting immune memory against hepatitis B in children after primary immunization with 4 doses of DTPa-HBV-IPV/Hib in the first and 2nd year of life.

Background: Few studies have assessed long term persisting immunity against hepatitis B virus (HBV) in children vaccinated during infancy with combined vaccines containing recombinant HBV surface antigen (HBs). We assessed antibody persistence and immune memory in children 4-5 years of age, previously vaccinated with four doses of combined hexavalent DTPa-HBV-IPV/Hib vaccine (Infanrix hexa).

Methods: Immune memory was assessed in 301 children through administration of a challenge dose of monovalent HBV vaccine.

Immunological persistence in 4-6 and 7-9 year olds previously vaccinated in infancy with hexavalent DTPa-HBV-IPV/Hib.

Background: The combined diphtheria-tetanus-pertussis-hepatitis B-inactivated poliomyelitis-Haemophilus influenzae conjugate vaccine (DTP a-HBV-IPV/Hib, Infanrix Hexa() GlaxoSmithKline Biologicals, Rixensart, Belgium) is the only hexavalent vaccine currently licensed for primary and booster vaccination of infants and provides simultaneous protection against six major diseases of childhood. The persistence of the immune response in children aged 4-6 and 7-9 years of age previously vaccinated with four doses of DTP a-HBV-IPV/Hib vaccine was assessed (www.clinicaltrials.

Immune memory to hepatitis B virus in 4-9-year old children vaccinated in infancy with four doses of hexavalent DTPa-HBV-IPV/Hib vaccine.

The combined hexavalent diphtheria-tetanus-acellular pertussis-hepatitis B-inactivated polio Haemophilus influenzae type b (DTPa-HBV-IPV/Hib) vaccine produces similar hepatitis B responses as the HBV monovalent vaccine. Booster vaccination of immunocompetent individuals primed against hepatitis B in infancy is currently not recommended. We investigated persisting immunity to hepatitis B in 4-6 (Study A; 106745) and 7-9 (Study B; 106744) year-old children primed in infancy and boosted in the second year of life with DTPa-HBV-IPV/Hib.