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Immune response to Hepatitis B vaccine among children in Yemen

Talal A Sallam1, Haifa M Alghshm, Arwa A Ablohom

  • 1Department of Microbiology, Faculty of Medicine and Health Sciences, Sana'a University, PO Box 12586, Sana'a, Yemen. talalsallam2000@yahoo.com

Saudi Medical Journal
|March 17, 2005
PubMed

Insights

Hepatitis B vaccine (HBV) shows a high response rate in Yemeni children, but over 30% need further evaluation for revaccination or booster doses. Antibody levels decrease with age, highlighting the need for ongoing HBV vaccine efficacy monitoring.

Area of Science:

  • Immunology
  • Vaccinology
  • Public Health

Background:

  • Hepatitis B vaccination is part of Yemen's National Extended Program for Immunizations (EPI).
  • Assessing long-term immune response to the hepatitis B vaccine (HBV) in children is crucial for public health strategies.

Purpose of the Study:

  • To evaluate the immune response to the hepatitis B vaccine (HBV) in children seven years after its inclusion in Yemen's EPI program.
  • To determine antibody levels and identify factors influencing vaccine efficacy in a pediatric population.

Main Methods:

  • Quantified anti-HBs antibody levels in 170 children (aged 13-73 months) who completed the 3-dose HBV vaccine series.
  • Assessed past hepatitis B virus (HBV) infection by testing for total anti-HBc antibodies.
  • Analyzed demographic and socioeconomic factors influencing immune response.

Main Results:

  • 83.5% of children demonstrated an adequate immune response (anti-HBs ≥ 10 mIU/ml).
  • Only 2% showed reactivity to anti-HBc, indicating the response was primarily vaccine-induced.
  • A significant inverse correlation was observed between antibody levels and socioeconomic status (p=0.02).

Conclusions:

  • A high seroprotection rate was observed, but 32.4% had inadequate or low antibody levels, suggesting a need for revaccination or booster doses.
  • Declining antibody levels with increasing age warrant careful monitoring of HBV vaccine effectiveness in Yemen.
  • Demographic factors like gender, room occupancy, and paternal education did not significantly impact vaccine response.
Abstract

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