Hepatitis B Surface Antigen Should Not Be the Only Sought Marker to Distinguish Blood Donors towards Hepatitis B Virus Infection in High Prevalence Area

Abstract

Since its discovery by Blumberg in 1965, the hepatitis B surface antigen (HBsAg) is used as the fingerprint of hepatitis B infection. Occult hepatitis B infection (OBI) is defined by a viral replication (DNA detectable) in the absence of HBsAg. Burkina Faso is a high endemic area where the prevalence is higher than 14%. At the National Center for Blood Transfusion (NCBT) of Ouagadougou, HBsAg is the only sought marker used to distinguish donors towards Hepatitis B Virus (HBV). Acceptation of blood donation is based specifically on the absence of HBsAg, which exposes to the risk of HBV transmission during transfusion. The goal of this study is to evaluate this risk by determining the prevalence of OBI in blood donors. Patients and Methods : It was a five - month prospective study on blood donations collected from January to May 2016. The HBc antibody has been sought in the serums of negative HBsAg donors. The measure of B DNA by Real Time PCR (polymerase chain reaction) and that of antibodies anti-HBs have been proposed to anti-HBc positive donors. Abdominal ultrasound, the transaminases, prothrombin level, alphafeto-proteins, hepatic fibrosis have been proposed to donors who were detectable for the DNA. Sociodemographic parameters have been collected. The test costs were borne by donors who were recalled by phone to adhere to the study. Results: Among 1980 negative donors HBsAg, 872 (44%) were positive for anti-HBc. 160 on 872 donors were received for consultation , among which 76 (76/160) were able to realise DNA which was detectable in 25 donors on 76, thus a prevalence of 32.8%. The mean value of DNA was 953 IU/ml. Physical examination and hepatic ultrasounds were normal except a case where hepatic steatosis was found. The biologic standard hepatic results were in normal range. None of the patient was able to realise hepatic fibrosis evaluation. A case of co-infection HIV/OBI was noted. Conclusion: This study shows that in Burkina, almost half of blood bags transfused are anti-HBc positive and around one third (32.8%) probably ha ve HBV DNA. This poses a potential risk of contamination for non-immunized recipient. It is thus important that, in addition to HBsAg, Anti-HBc should be systematically sought in order to minimize the risk.