566 PREVALENCE OF HBV AND RELATED RISK FACTORS IN HIGH SCHOOL AND UNIVERSITY COMMUNITY OF BANGUI (CENTRAL AFRICAN REPUBLIC)

Abstract

Background and Aims: Hepatitis B virus (HBV) is the major cause of chronic hepatitis, cirrhosis, and hepatocellular carcinoma. HBV has three major modes of infection: parenteral inoculation, sexual transmission and perinatal transmission from mother to infant. The global epidemiological scenario of HBV infection has been changing rapidly over the last two decade due to an effective immunization programme initiated by the World Health Organization. Because the risk of chronic infection increases with decreasing age, people who are infected in early childhood experience a disproportionately large burden of disease attributable to HBV. The objective of our study is to estimate the prevalence of HBV and identify the risk factors of transmission of the HBV among adolescents and young adults to know the precise mode and dynamics of HBV transmission in our country. Methods: Eight hundred and one (801) adolescents from high school and young adults from university were included in the study with their consent. The parental consent was required for subjects under 18 years old. Dried blood spot (DBS) from each participant were prepared by spotting 3 drops of whole blood (4 spots) from the same fingerprick onto Whatman filter paper. Blood samples were extracted from DBS by punching one bloodstained disk of 6mm diameter from the filter paper, and then eluting overnight in 500ml PBS. An aliquot of eluate was then processed with commercial ELISA tests (Abbott Murex, Dartfort, UK) according to manufacturer procedures to detect HBsAg antigen, Anti-HBc and Anti-HBs antibodies. Results: Global seroprevalence of HBV is 42.3%. Prevalence of HBV markers: HBsAg: 15.5% (including 13.3% for adolescents and 19.9% for young adults); Anti-HBc antibody: 41.1% and 3.7% for the anti-HBs antibody. The prominent risk factors are sexual activity, familial antecedent of HBV, socioeconomic conditions (orphans, low income families, hygiene conditions) and drug. On the contrary, blood transfusion, multiple sexual partner, age, tattooing, surgery and dental surgery are not associated with the HBV transmission in the studied population. Conclusion: Results suggest that socioeconomic conditions and sexual activity are the prominent risk factors for HBV transmission in this study. Immunization program should be reinforced by national authorities.