Study on immunity against Hepatitis (Hep) B in children after vaccination during infancy and assessment of knowledge about Hep B infection among mothers of Gampaha District

Abstract

Study on immunity against Hepatitis (Hep) B in children after vaccination during infancy and assessment of knowledge about Hep B infection among mothers of Gampaha District

Fernando, K.M.D., Molecular Medicine Unit, Faculty of Medicine, University of Kelaniya, Ragama, Sri Lanka

Hepatitis (Hep) B is a potentially life threatening liver infection caused by a virus. It is important to know whether immunity produced by vaccination during infancy last up to adolescence. Sound knowledge about Hep B infection would promote mothers to vaccinate their children against Hep B. Objective of this study was to assess the Hep B surface Antibody (anti-HBs) status in children aged ten years after Hep B vaccination during infancy and knowledge about Hep B infection among mothers in the District of Gampaha, Sri Lanka.

In the PART 1 of the study, assessment of anti-HBs status after Hep B vaccination during infancy was conducted with 150 children (10 years old) with evidence of Hep B vaccination at 2, 4 and 6 months during infancy. After quantitative detection of anti-HBs using Enzyme-Linked lmmunosorbent Assay (ELISA), majority of children 85.33% (128/150) showed protection level of anti-HBs .C::.10 mIU/ml).

In the PART 2 of the study, assessment of efficacy of a booster dose of Hep B vaccine in children who had Ab levels below protective level (< 10 mlU/ml) in the PART 1 was conducted with 22 children. They were offered a free booster dose and retested one month after the . booster . All children showed Ab response above 10 mIU/ml, while 81.81% ( 18/22) had a titre > 100 mlU/ml.

In the PART 3 of the study, assessment of knowledge about Hep B infection among mothers in the District of Gampaha, Sri Lanka was assessed with 800 mothers. Overall knowledge of Hep B, educated population had a high score, while not educated population had the minimum score. Even though the mothers in all groups had notable levels of knowledge on transmission of Hep B, their awareness on complications and prevention were relatively low. Therefore, the awareness programs conducted by the relevant sector should focus more on the above aspects to improve the overall knowledge of mothers on Hep B.

Vaccination against Hep B during infancy appears to produce protective level of Ab at 10 years of age. Even the children with Ab titres below protective level produced a sharp rise in titres with a booster dose. Though we have a good immunization coverage mothers seem to have a very poor knowledge about Hep B.