ANTIBODY RESPONSE TO BOOSTER DOSES OF HEPATITIS B VACCINE IN MEDICAL STUDENTS VACCINATED IN INFANCY

• Published in: International journal of infectious diseases Vol. 134; pp. S17 - S18
• Main Authors: Noh, R. Mohd, Jalil, A. Abd, Ibrahim, A., Sahlan, N.
• Format: Journal Article
• Language: English
• Published: Elsevier 01.08.2023
• ISSN: 1201-9712
• DOI: 10.1016/j.ijid.2023.05.061

Intro: Hepatitis B vaccination has been included in the Malaysian infancy vaccination schedule since 1989. Post-vaccination antibody measurements are not recommended after routine vaccination, and non-responders are not identified. Healthcare workers are considered at high risk of being infected with hepatitis B through work-related injuries and are recommended to prevent infection through vaccination if they do not have protective levels of antibodies. Antibody levels measured years after primary vaccination will be low due to natural waning. We conducted this study to determine the antibody levels after one, two and three doses of hepatitis booster vaccine doses in individuals who have completed primary vaccination in infancy. Methods: We performed a descriptive prospective study to determine the effect of booster hepatitis B vaccines by measuring the anti-HBs levels after booster vaccination on a group of medical students who had completed three doses of primary vaccination in infancy but no longer have protective levels of antibody for hepatitis B surface antigen (anti-HBs <10 mIU/ml). Antibody levels were measured at 0 (prior to the first dose), 7 days after the first dose, 28 days (prior to the second dose), 6 months (prior to the third dose) and one month after the last dose of vaccine. Findings: 152 second-year medical students consented to be included in the study. Only 56 were able to provide written evidence of vaccine completion, 11 already had an anti-HBs >/= 10 mIU/ml, and seven were excluded because they were unable to complete the study. Conclusion: 83.78% of the participants were able to achieve protective levels of antibodies after the first dose of the hepatitis B booster vaccine and only 16.22% required a second dose to increase antibodies to protective levels.