Molecular characteristics of HBV infection among blood donors tested HBsAg reactive in a single ELISA test in southern China

Abstract

Background Hepatitis B virus (HBV) infection is a major concern for blood safety in high-prevalence HBV countries such as China. In Shenzhen, dual hepatitis B surface antigen (HBsAg) enzyme-linked immunosorbent assays (ELISAs) have been adopted in parallel with nucleic acid testing (NAT) for donors for over a decade. A small proportion of blood donors test reactive (R) for HBsAg but negative through routine NAT, which can lead to HBV infection with an extremely low viral load. Objectives We aimed to investigate and analyze the molecular characteristics of HBV among blood donors that tested HBsAg R in a single ELISA test. Methods Blood donations were evaluated in this study if confirmed HBsAg R through one of two ELISA kits. Samples with non-reactive (NR) results by NAT were collected and tested for HBsAg by chemiluminescent microparticle immunoassay (CLIA) with a neutralization test. The level of HBsAg was further assessed by electrochemiluminescence immunoassay (ECLIA). The viral basic core promoter (BCP) and pre-core (PC) and S regions were amplified by nested PCR. Quantitative real-time PCR (qPCR) for viral load determination and individual donation (ID)-NAT were adopted simultaneously. HBsAg was confirmed with CLIA, ECLIA, nested PCR, qPCR, and ID-NAT. Results Of the 100,252 donations, 38 and 41 were identified as HBsAg R with Wantai and DiaSorin ELISA kits, respectively. Seventy-nine (0.077%, 79/100,252) blood samples with ELISA R-NR and NAT NR results were enrolled in the study. Of these, 17 (21.5%,17/79) were confirmed as HBsAg-positive. Of the 14 genotyped cases, 78.6% (11/14) were genotype B, and C and D were observed in two and one sample, respectively. Mutations were found in the S gene, including Y100C, Y103I, G145R, and L175S, which can affect the detection of HBsAg. A high-frequency mutation, T1719G (93.3%), was detected in the BCP/PC region, which reduced the viral replication. Conclusion A small number of blood samples with HBsAg ELISA R-NR and NAT NR results were confirmed as HBV infection, viral nucleic acids were found in most of the samples through routine NAT methods. It is necessary to employ more sensitive and specific assays for the detection of HBV infection among blood donors.

Cost-benefit analysis of serological and nucleic acid testing for hepatitis B virus in blood donors in southern China

“…An American comprehensive study from 22.4 million blood donors screened by HBsAg, anti-HBc, and NAT also revealed that only 43/404 (10.6%) OBIs could be detected by MP-NAT, while most of OBIs (361/404, 89.4%) with low viral loads could only be identi ed by ID-NAT[24]. This conclusion was consistent with another previous study which reported HBV MP NAT failed to detect approximately 92% (46 of 593) of OBI donors[25]. Out of 103,356 seronegative Chinese blood donations, Fifty-six out of 98 reactive MPs (57.1%) were resolved as HBV DNA+, but 17 non-resolved donations identi ed as OBIs by alternative NAT assays were missed by MP-NAT[12].…”

Simple and Feasible Detection of Hepatitis B Virus via Combination of Multienzyme Isothermal Rapid Amplification and Lateral Flow Dipstick Strip

“…Thus, it is not suitable for popularization in a resource-limited area ( Weber et al, 2019 ). Another method, enzyme-linked immunosorbent assay (ELISA) usually takes 1∼2 days to get the detection result, and the antibody preparation cycle is long ( Ye et al, 2021 ).…”