Comprehensive analysis of hepatitis B virus infections in blood donors in southern China that are surface antigen positive but nucleic acid testing negative

Abstract

BACKGROUNDHepatitis B virus (HBV) infection is one of the major concerns for the safety of blood transfusion in high‐prevalent countries such as in China. Prior studies outside of China have shown hepatitis B surface antigen (HBsAg) false‐reactive rate of 0.02% to 0.04%. Similarly, false‐negative HBsAg and HBV DNA results may occur in infected donors. Our study analyzed HBsAg enzyme‐linked immunosorbent assay (ELISA)‐reactive but NAT‐negative donations in Shenzhen Blood Center, China.STUDY DESIGN AND METHODSHBsAg ELISA‐positive/NAT‐negative plasma samples identified from screening 101,025 donations during 2017‐2018 were analyzed by molecular and serologic tests including neutralization, chemiluminescence immunoassays, and various HBV DNA amplification assays. Molecular characterizations of HBsAg‐positive/NAT‐negative samples were determined by quantitative polymerase chain reaction (qPCR) and nested PCR amplification of the basic core and precore promotor regions (295 base pairs) and HBsAg (S) region (496 base pairs).RESULTSScreening of 101,025 eligible blood donations identified 157 (0.16%, 95% confidence interval, 0.13%‐0.18%) HBsAg ELISA‐positive/NAT‐negative plasma samples; of those, 71 (45.2%) were HBsAg confirmed positive by further HBsAg testing and DNA positive by molecular tests with increased sensitivity. Of the 71, all but one was antibody to hepatitis B core antigen reactive without antibody to hepatitis B surface antigen, yielding one recent (window‐period) HBV infection. Of the remaining donations, 80 (51%) were not considered as HBV‐infected donors, and 6 (3.8%) were interpreted as indeterminate since HBsAg results were discordant with unconfirmed HBV DNA results. In the 71 confirmed positives, HBsAg levels ranged from 0.05 to 400 IU/mL and HBV DNA from 6 to 2654 IU/mL; however, the correlation between the two was weak (R2 = 0.24).CONCLUSIONFewer than half of HBsAg ELISA‐positive/NAT‐negative samples were confirmed as HBsAg positive. Our study demonstrates that in highly HBV‐endemic countries, assays with high sensitivity and specificity may be required.

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

“…In addition, individual donation NAT (ID-NAT) (Cobas TaqScreen MPX Test, version 2.0, Roche Diagnostic GmbH, Mannheim, Germany; 1.0 mL, LOD, 2.3 IU/mL) was used for the detection of HBV DNA. HBsAg-positive results were confirmed by reactivity in CLIA and/or ECLIA, as well as any reactive results in qPCR, nested PCR, and ID-NAT [7].…”

“…HBsAg and HBV DNA screening were implemented among blood donors to decrease the risk of HBV transmission through blood transfusion [9]. Complicated infectious modes, such as OBI, HBsAg ELISA R-NAT NR, and ELISA R for HBVassociated markers, have been reported in Shenzhen blood donors [7,10]. The occurrence of such complications restricts the reliability of HBV detection in China.…”

Molecular Characteristics of HBV Among Blood Donors in Southern China with Different HBsAg ELISA Results by Two Kits

“…Besides, individual donation NAT (ID-NAT) (Cobas TaqScreen MPX Test, version 2.0 (Roche Diagnostic GmbH, Mannheim, Germany) (1.0 mL, LOD, 2.3 IU/mL) was adopt for the detection of HBV DNA. The positive result of HBsAg was con rmed by the reactivity in CLIA and/or ECLIA, as well as any reactive results in qPCR, nested-PCR and ID-NAT [7].…”

Comparative Analysis of Hepatitis B Virus Infections in Blood Donors Born Before and After the Implementation of Universal HBV Vaccination in Southern China

“…200ul-2500ul HBsAg ELISA + and / or NAT initial reactive samples were extracted for HBV DNA by HighPure Viral Nucleic Acid Large Volume Kits(Roche Diagnostics Gmbh, Mannheim, Germany). The basic core promoter / pre-core (BCP / PC) and S region were amplified by qPCR and nested PCR for further detection [7,8]. As mentioned above, the samples reacted by any two of the five NAT methods were confirmed to be DNA positive.…”

“…HBV vaccinees were gradually becoming the majority of blood donors in China and impacting blood safety positively. In our previous studies for exploring the true HBV infection in blood donors, 80 were classified as occult HBV infection (OBI) from 307,740 sero-negative blood samples [6], and 121/259(46.7%) non-discriminated reactive samples of 123,280 donations were identified as OBIs, and a number of important mutations were detected additionally [7], Furthermore, 71/159(44.7%) HBsAg ELISA-positive and NAT-negative samples of 101,025 blood donations were confirmed as HBsAg positive [8]. These measurements could interdicted more OBIs with extremely lower viral loads and chronic hepatitis B infections with low level HBsAg in Chinese blood donors, thus reducing the risk of HBV infection after transfusion [9].…”