Genotypes Of Hepatitis B Virus Among Voluntary Blood Donors In Kinshasa, Democratic Republic Of Congo

ABSTRACT

Hepatitis B represents a major global health problem. Despite the high endemicity of hepatitis B in Sub-Saharan Africa, little is known about the epidemiology and genotypes of hepatitis B virus (HBV) in Africa. The few published studies that describe the genetic characteristics of HBV in the Democratic Republic of Congo (DRC) involved a very small adult population size. In the present study, epidemiological and molecular characteristics of HBV infection were studied among voluntary blood donors (n=582) at the National Blood Transfusion Centre in Kinshasa, DRC. After obtaining an informed consent, a questionnaire was administered to collect socio-demographic data, followed by blood collection. Sampled blood was screened for hepatitis B surface antigen (HBsAg) using enzyme-linked immunosorbent assay (ELISA). The prevalence of HBsAg among voluntary blood donors in Kinshasa was found to be 6.9 % (40/582). Blood donors aged between 28 and 37 years had the highest HBsAg prevalence. Using PCR targeting the partial S gene, HBV-DNA was detected in 50% (20/40) of HBsAg positive samples and afterwards sequenced in order to perform phylogenetic analysis. Nine (60.0 %), four (26.6 %) and one (6.7 %) out of the 15 HBV nucleotide sequences clustered into genotypes A, E and D, respectively. One (6.7 %) HBV nucleotide sequence did not cluster with any of the known genotypes and could be a novel genotype, subgenotype or recombinant HBV. The present study confirms that HBV infection is endemic in Kinshasa and demonstrates that HBV genotype A predominates in adults. Further studies are needed to assess detailed virological and clinical characteristics of HBV genotypes, as well as the existence of HBV recombinant genotypes in DRC, which may have an impact on clinical outcomes, drug effect and vaccination efficacy.