Related Experiment Videos
A 7-year follow-up of newborns vaccinated against hepatitis B
M L Gonzalez1, J B Gonzalez, F Salva
1Department of Gynecology and Obstetrics, Hospital Son Dureta, Palma de Mallorca, Spain.
Insights
Hepatitis B vaccination in infants born to carrier mothers shows declining antibody levels over time. A booster dose is effective in restoring protective immunity, indicating timely revaccination is crucial for long-term protection.
Area of Science:
- Pediatrics
- Immunology
- Hepatology
Background:
- Hepatitis B virus (HBV) infection poses a significant global health risk.
- Infants born to mothers with chronic hepatitis B surface antigen (HBsAg) are at high risk of perinatal transmission.
- Neonatal vaccination is a key strategy to prevent HBV infection.
Purpose of the Study:
- To evaluate the long-term immunogenicity of birth dose hepatitis B vaccination in infants born to HBsAg-positive mothers.
- To determine the optimal timing for booster vaccination based on anti-HBs titres.
Main Methods:
- Longitudinal serological assessment of anti-HBs titres in 79 infants over 7 years.
- Administration of a booster dose to children with sub-protective antibody levels.
- Statistical analysis of titre changes and duration of protective immunity.
Main Results:
- Anti-HBs titres in responders decreased significantly from 1 to 7 years post-vaccination.
- A booster dose effectively increased titres in children with low anti-HBs levels (p < 0.001).
- Initial high titres correlated with longer duration of protective immunity (3-5 years).
Conclusions:
- Hepatitis B vaccine-induced immunity wanes over time in infants born to carrier mothers.
- Booster vaccination is necessary to maintain protective anti-HBs titres.
- Initial anti-HBs titres after neonatal vaccination can predict the need for booster doses.
Abstract:
Of 79 children born to asymptomatic HBsAg chronic carrier mothers and vaccinated at birth against hepatitis B, a total of 71, 66 and 56 could be serologically assessed after 1, 5 and 7 years, respectively. Anti-HBs titres (geometric means) of responders decreased from 2475 to 143 IU l-1 between 1 and 5 years of age and dropped to 82 IU l-1 by 7 years. At this time, a booster dose given to 34 children who showed anti-HBs titres lower or slightly higher than 100 IU l-1 significantly increased titres from 34 to 2985 IU l-1 (p < 0.001). Children whose titres following perinatal vaccination reached 100 to 1000 IU l-1 or above 1000 IU l-1 maintained protective levels (> 10 IU l-1) for 3 and 5 years, respectively. As in adults, anti-HBs titres recorded after the initial vaccination indicate the time at which infants should receive booster vaccination.