Protective hepatitis b antibodies (anti-HBs) after three doses of hepatitis b vaccine in a cohort of children in Riyadh, Saudi Arabia

Abstract

The hepatitis B vaccine was added as the seventh primary immuiiugen of the Expanded Program on Immunisation (EPIj in October 1989 in the Kingdom or Saudi Arabia hut the schedule was not altered. It consists uf active varcinalion at birth, six weeks and (lien six months of aye without hepatitis B surface antigen (HBsAg) screening. The objective of this siudv was to determine the scrnpositivity rate or antibody to hepa(ili> B surface antigen (anti-HBs) after three doses of hepatitis B vaccine in children who came for pediatric check up service at Sulaimun Al-Habih Medical Center in Riyadh. Saudi Arabia. A retrospective chart review was conducted for all the children starring from January I u97 at the private medical center in Riyadh, Saudi Arabia. Anfl-HBs titre equal to or higher than 10 inlU.'mL is considered positive. * 'One thousand and ei^ht patients satisfied our rriteria and were included in the study. Their age ranged hetwecn 0-75 - IK years (mean 7.1 +• 3.7 years). Five hundred and nmclytwo (58.7%) were males and 416 (41.3%) were females. Overall seropositiviiv rate was H.3.1 % with the higher rate in those younger than seven years of age (X6.7%) and lower rate in (hose older than seven years (7g.7%). The mean age of the seropositive gruup WflS significantly less than that uf the seronegative group (I' < 0.01) Thrre was no difference helween Ihe rate of seroposilivity hetween males and females. We conclude that the overall seropositivlty rale in Saudi Arabia is 83%, The rate in infants following universal infant hepatitis B vaccination is acceptable. Further studies are needed in older children and adolescents.