title: Long-term protection of hepatitis B vaccine 18 years after vaccination.
abstract: BACKGROUND
  This is the third evaluation study of the hepatitis B virus (HBV) vaccination program, initiated in 1989 in Saudi Arabia.
  
  
  OBJECTIVE
  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.
authors.affiliation: Department of Medicine, College of Medicine, King Saud University, P.O. Box 2925(59), Riyadh 11461, Saudi Arabia.
authors.forename: Faleh
authors.initials: F
authors.lastname: Alfaleh
authors.forename: Suliman
authors.initials: S
authors.lastname: Alshehri
authors.forename: Saleh
authors.initials: S
authors.lastname: Alansari
authors.forename: Mohammed
authors.initials: M
authors.lastname: Aljeffri
authors.forename: Yaqoub
authors.initials: Y
authors.lastname: Almazrou
authors.forename: Ahmad
authors.initials: A
authors.lastname: Shaffi
authors.forename: Ayman A
authors.initials: AA
authors.lastname: Abdo
mesh_terms: D000293:Adolescent; D005260:Female; D006509:Hepatitis B / Q000453:epidemiology* / Q000517:prevention & control*; D006510:Hepatitis B Antibodies / Q000097:blood; D006511:Hepatitis B Antigens / Q000097:blood; D017325:Hepatitis B Vaccines / Q000008:administration & dosage / Q000276:immunology*; D006801:Humans; D007110:Immunity, Active; D007117:Immunization, Secondary; D007223:Infant; D008297:Male; D012529:Saudi Arabia / Q000453:epidemiology; D013997:Time Factors; D014611:Vaccination
chemical_list: D006510:Hepatitis B Antibodies; D006511:Hepatitis B Antigens; D017325:Hepatitis B Vaccines