Efficacy of hepatitis B vaccine in a cohort community-based study in Riyadh and Hail regions of Saudi Arabia

ABSTRACT

Saudi Arabia used to by hyperendemic for HBV infection. Most of infection occurs in early life. HBV vaccine was, therefore, introduced in 1989 as the seventh primary immunogen of the EPI Program. This study is conducted to evaluate the efficacy of this program in Riyadh and Hail Regions. Method and Patients A cohort follow-up study of children from Riyadh and Hail, who had been vaccinated in 1989, evaluated in 1991 and tested for HBV markers six years later. The files of 303 children from Riyadh and Hail, who were investigated in 1991retrieved and only 119, were available for testing. Fifty% of the children have still a protective anti- HBs tittr. One vaccinated child was found to be positive for HBs Ag. According to this study, the efficacy rate against HBs Ag carriage is 88%. This study demonstrates the tremendous effect of HB vaccine on the HBV infection of Saudi children in these two regions