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

Abstract

BackgroundFew 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™).MethodsImmune memory was assessed in 301 children through administration of a challenge dose of monovalent HBV vaccine.ResultsAt 4-5 years of age, 85.3% of subjects had persisting anti-HBs antibody concentrations ≥ 10 mIU/mL, rising to 98.6% after the HBV challenge dose. All but 12 subjects (95.8%) achieved post-challenge anti-HBs concentrations ≥ 100 mIU/mL. The post-challenge anti-HBs GMC rose by 100-fold compared to pre-challenge concentrations. An anamnestic response to the HBV vaccine challenge was observed in 96.8% of subjects, including 17/21 (81.0%) of children with initially undetectable antibodies (<3.3 mIU/mL). All but 4 of 42 subjects (90.5%) with anti-HBs antibodies <10 mIU/mL prior to the challenge dose, achieved seroprotective levels afterwards. A 4-fold rise in antibody concentration after the challenge dose was observed in 259/264 (98.1%) of initially seropositive subjects. The magnitude of the post-challenge responses was proportional to pre-challenge anti-HBs levels. No serious adverse events were reported during the study.ConclusionThe combined DTPa-HBV-IPV/Hib vaccine induced lasting immune memory against hepatitis B. Long term protection afforded by DTPa-HBV-IPV/Hib is likely to be similar to that observed following priming with monovalent HBV vaccines.Trial registrationhttp://www.clinicaltrials.gov 106789 NCT00411697

Five-year post vaccination efficacy of hepatitis B vaccine in rural Nigeria

“…The vaccine effectiveness against chronic carriage is similar to the 80% obtained in this community in an earlier study. 16 Thus this study is in agreement with others that show that the HB vaccine is effective, protects subjects for a fairly long period [11][12][13]23 and thus prevents the development of complications of HB infection in such vaccinated children.…”

“…24 This is not unexpected as it is well known that antibody levels decay in an exponential manner with time. [11][12][13]23 It should be noted that the proportion of vaccinated subjects with protective anti-HBs …”

Immune memory to hepatitis B persists in children aged 7–8 years, who were vaccinated in infancy with 4 doses of hexavalent DTPa-HBV-IPV/Hib (Infanrix™ hexa) vaccine

“…In clinical trials in Germany, in which children were vaccinated with 4 doses of DTPa-HBV-IPV/Hib in infancy, between 85.3% and 91.0% had persisting anti-HBs ≥10 mIU/mL at 4-6 y of age. 12,18,19 This compares with anti-HBs ≥10 mIU/mL in 92.9% of 4-6 y old vaccinated with 4 doses of Engerix™ B. 18 An anamnestic response to the challenge dose was observed in 95.7% to 96.8% of DTPa-HBV-IPV/Hib-primed children.…”

“…18 An anamnestic response to the challenge dose was observed in 95.7% to 96.8% of DTPa-HBV-IPV/Hib-primed children. 12,19 In 7-to 9-y-old children vaccinated with 4 doses of DTPa-HBV-IPV/ Hib in infancy, anti-HBs concentrations ≥10 mIU/mL persisted in 78.0% of subjects and an anamnestic response was observed in 98.9%. 19 These results are consistent with those of the present analysis.…”

Sero-epidemiology of hepatitis B markers in the population of Tuscany, Central Italy, 20 years after the implementation of universal vaccination

“…However, the combined vaccine induces a lasting immune memory against hepatitis B; therefore, long term protection is likely to be similar to that observed following priming with monovalent HBV vaccines. [21][22][23][24][25] At present time, routine booster doses of hepatitis B vaccine do not seem necessary to sustain immunity in children vaccinated with hexavalent vaccines.…”