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First evaluation of the serum level of anti-hepatitis B surface antigen after vaccination in Libya
Insights
Hepatitis B vaccination in Libya provides strong initial protection, but antibody levels decrease over time. A booster dose at age six is recommended for sustained immunity in children.
Area of Science:
- Immunology
- Public Health
- Pediatrics
Background:
- Libya's hepatitis B virus (HBV) vaccination schedule aligns with global standards.
- The HBV immunization program in Tripoli requires evaluation for long-term efficacy.
Purpose of the Study:
- To assess the durability of HBV vaccine-induced immunity in children in Tripoli.
- To identify the optimal timing for administering booster doses to maintain protective antibody levels.
Main Methods:
- Serum samples from 277 children aged 1-12 years were analyzed for hepatitis B surface antigen.
- Antibody titers were measured to evaluate the immune response and persistence post-vaccination.
Main Results:
- Initial vaccine response in 1-3-year-olds was high (93.2%).
- Protective antibody titers (> or = 10 mIU/mL) declined significantly by 7-9 years post-vaccination (53.1%).
- No significant sex-based differences in antibody persistence or vaccine response were noted.
Conclusions:
- The ongoing HBV vaccination program is supported by the findings.
- A booster dose at age six is recommended to ensure sustained protection, particularly before school entry.
Abstract:
The hepatitis B virus (HBV) vaccination schedule in Libya follows international recommendations (1st dose at birth, 2nd after 1 month and 3rd after 6 months). This research aimed to evaluate the long-term protection of the HBV immunization programme in Tripoli and to determine the best age to administer booster doses. Serum levels of hepatitis B surface antigen were determined in 277 randomly selected children aged 1-12 years. The response to HBV vaccine in 1-3-year-olds was 93.2%, but this declined with age and at 7-9 years after initial vaccination only 53.1% of children had protective titres (> or = 10 mIU/mL). No significant differences between males and females in antibody persistence or response to vaccine were observed. We recommend continuing the HBV vaccination programme and that a booster dose be given to 6-year-old children to ensure maximum protection during the period of school entry and beyond.
