Serological and Molecular Detection of Hepatitis B Virus among High Risk group in Sudan

Abstract

Sudan has a high HBV seroprevalence of greater than 8% HBsAg- positivity, it is can be transmitted through blood or body fluids, by both, vertical and horizontal routes of transmission. In the population at high risk such as hemodialysis patients , blood recipients and pregnancy, cross contamination via blood is mainly responsible for hepatitis B virus infection transmission. The ordinary method used for screening is ELSA technique. Nucleic acid testing (NAT) for blood screening enable detecting HBV infection in the window period, therefore, the introduction of NAT has a great role in detecting the positive sample. The aim of this study was to determine the prevalence of HBcAb, HBsAg and HBV DNA among high-risk Sudanese population to determine the impact of these markers testing in detecting hepatitis B infection. In this study 432 specimens; 111 samples were blood donors, 168 were hemodialysis and 153 sample were pregnant ladies were collected from healthy population as they was reported as HBsAg negative. Personal, socio-demographic data and risk factors (e.g. age, HBV vaccination, previous blood donation, previous organ transplantation, and past history of bilharziasis) was included in the study. All samples were retested for HBsAg, anti-HBcAb using ELISA. Presence of hepatitis B virus (HBV) DNA was checked by conventional polymerase chain reaction (PCR) Out of samples enrolled in this study 38 (8.8%) were HBsAg negative. 61 (14.1%) were HBcAb positive . The frequency of HBcAb and HBsAg is found to be higher among blood donors, than other population, male than female , more distributed among the age 20-40 years (56.3%) than age group less than 20 years (7.2%) and above 40 (36.6%). No samples were positive for HBV-DNA, indicating OBI frequency of 0%. No other clinical characteristics (previous infection with Hepatitis, tissue transplantation, infection with Bilharzia) were significantly associated with HBsAg or anti-HB core seropositivity among all study group. Moderate prevalence of HBV infection markers was found among negatively reported population under study, these indicate caution in HBV screening and recommend the use of more sensitive assay (other than the conventional PCR technique)to detect HBV DNA at a very low concentration, below the limit of detection. Improving the quality of laboratory screening of blood, in blood bank setting, for HBV is one of the components in reducing the risk for transfusion-transmitted HBV.