Protective immunity in a sample of healthy adults following vaccination with a more cost effective recombinant HBsAg vaccine

Abstract

Background: Vaccines against hepatitis B virus (HBV) infection became available from 1982, however, the HBV infection remains as a public health issue due to infection among susceptible individuals. Many HBV vaccines are available and until 2012, Sri Lanka has been using vaccines produced by different Pharmaceutical companies. Since 2012, Sri Lanka imported HBV vaccine from Serum Institute of India as the product was more cost effective. However, the immune response to this vaccine has never been studied in the country. Objective: The current study was carried out to assess the immune response (anti-HBs) to the recombinant HBV surface antigen (HBsAg) vaccine (Serum Institute, India), which is currently used in the state healthcare sector of Sri Lanka. Study design: A sample of vaccinated healthy adults (n=529), age ranged between 20-29 years were enrolled in this study after completing the standard 3-dose regimen of HBV vaccination from early 2015 to 2016. Sociodemographic data were collected using a self-administrated questionnaire. Serum samples were tested to detect the presence of anti-HBs using an enzyme linked immunosorbent assay (ELISA) and the results were analyzed using MS-Excel 2010. Results: Based on the results, 96.8% of the healthy adults had protective immune response with anti-HBs levels > 10 mIU/mL. Gender did not show an association with levels of anti-HBs. All the ethnic groups in the study sample exhibited >90% of protective immune response. Conclusion: The more cost effective recombinant HBsAg vaccine taken by the healthy adults in the present study was effective in inducing the protective immunity.

Keywords

• Hepatitis B virus
• Hepatitis B
• HBsAg vaccine
• Anti-HBs
• Sri Lanka