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Updated: Jun 29, 2026

Analysis of HBV-Specific CD4 T-cell Responses and Identification of HLA-DR-Restricted CD4 T-Cell Epitopes Based on a Peptide Matrix
Published on: October 20, 2021
Long-term protection of hepatitis B vaccine 18 years after vaccination
Faleh Alfaleh1, Suliman Alshehri, Saleh Alansari
1Department of Medicine, College of Medicine, King Saud University, P.O. Box 2925(59), Riyadh 11461, Saudi Arabia.
Introduction:
This is the third evaluation study of the hepatitis B virus (HBV) vaccination program, initiated in 1989 in Saudi Arabia.
Aims:
This study sought to assess the efficacy and long-term protection of the hepatitis B vaccine among Saudi adolescents.
Methods:
School students between the ages of 16 and 18 years were randomly chosen from high endemic (Aseer), intermediate endemic (Madinah), and low endemic (Al-Qaseem) areas of the country. Hepatitis B surface antigen (HBsAg), hepatitis B core IgG antibody (anti-HBc), and hepatitis B surface antibody (anti-HBs) were measured using standard techniques.
Results:
A total of 1355 students (689 males and 666 females) were selected randomly from the three areas. No cases of positive HBsAg or anti-HBc were detected among the study population. Five hundred and ten students (38%) showed protective anti-HBs titers (>/= 10mIU/ml), while 528 (39%) students had undetectable anti-HBs titers (<1 mIU/ml).
Conclusions:
This study shows the excellent efficacy of the HBV vaccination program in Saudi Arabia 18 years after its launch. Based on this study and others, a booster dose for the adult population appears to be unnecessary.
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