SEROLOGICAL MARKERS OF HEPATITIS B VIRUS INFECTIVITY AMONG HEPATITIS B SURFACE ANTIGEN-NEGATIVE BLOOD DONORS AT THE UNIVERSITY COLLEGE HOSPITAL, IBADAN

Abstract

Background: Hepatitis B virus infection is a global public health problem, the diagnosis of which is based on detection of hepatitis B surface antigen in the blood. In spite of this, transmission of HBV infection has been documented from hepatitis B surface antigen negative blood donations. There is paucity of data on prevalence of HBV markers in prospective donors who are HBsAg negative in Nigeria.

Objective: The objective of this study was to determine the prevalence of antiHBc, HBeAg, anti-HBe among apparently healthy blood donors who were negative for hepatitis B surface antigen and to establish whether there is a need for routine Hepatitis B core antibody screening of blood units.
Materials and Methods: A cross-sectional study was carried out among blood donors at the blood bank of the University College Hospital, Ibadan between May and October, 2013. The serum samples of 490 participants who were negative for HBsAg using Monolisa Ultra HBsAg ELISA kits by BIORAD France were further tested for anti-HBc, anti-HBs, HBeAg and anti-HBe using ELISA kits by DIAPRO Diagnostic Bioprobes Milano, Italy. A structured questionnaire was used to assess the socio-demographic characteristics and presence of possible risk factors.
Results: The mean age of participants was 32.5 years (±9.5), majority were males, 462 (94.3%) and 375 (76.5%) were first time donors. Of the four hundred and ninety blood donors considered fit for donation based on HBsAg negativity, 89 (18.2%) were positive for at least one serological marker of HBV (anti-HBc, antiHBs, and anti-HBe) and many of which were positive for more than one marker. Eighty-three(16.9%) were positive for anti-HBc, out of which 35 (7.1%) had antiHBc alone, 30 (6.1%) had both anti-HBc and anti-HBs while 18 (3.7%) were positive for anti-HBc, anti-HBs and anti-HBe. Antibody to HBsAg (anti-HBs) was detected in 54 (11%) donor samples, of which 6(1.2%) were positive for anti-HBs alone. The number of donors positive for anti-HBeAg was 18 (3.7%). However, no subject was positive for HBeAg.
Highest prevalence of HBV markers occurred in the 26-34 year age group. Independent risk factors associated with presence of at least one marker were age
(P-value=0.049), marital status (P-value=0.003), dental and surgical procedure (P<0.001), traditional practices such as tattoo, body piercing, scarification (Pvalue=<0.001) and previous history of blood transfusion (P-value=0.016).
Conclusion: This study has confirmed that some blood units containing other markers of HBV are being transfused to recipients even after screening for HBsAg is negative. These blood units are potentially infectious and can cause posttransfusion hepatitis in the recipients. There is need to consider introduction of testing for other markers of HBV infection in our blood banks. A large multicentre study to determine the prevalence of occult hepatitis B infection in Nigeria is suggested. Public health education on HBV infection and adult vaccination programmes should be initiated.