Alinity m, a Random-Access System, for Hepatitis B Virus DNA Quantification in Plasma and Whole Blood Collected on Dried Blood Spots.

The International Liver Association recommends the use of accurate and sensitive molecular methods for determination of hepatitis B virus (HBV) DNA levels in plasma or serum of chronic HBsAg carriers. The level of HBV replication represents the strongest predictive biomarker associated with disease progression and long-term outcome of chronic HBV infection. The purpose of this study was to evaluate the ability to the new Alinity m System to detect and quantify HBV DNA in plasma and whole blood collected on dried blood spots (DBS). Paired plasma and DBS samples from patients chronically infected with various HBV genotypes were tested in parallel for HBV DNA detection and quantification. There is a linear relationship between HBV DNA levels measured in plasma samples using the Alinity m HBV assay and the Xpert HBV viral load assay, used for comparison. A slight deviation (0.03 ± 0.31 log IU/mL) was observed within the quantitative range. In DBS, HBV DNA levels closely correlated with levels measured in plasma. All patients had detectable and quantifiable HBV DNA by DBS testing, except for one patient with a plasma HBV DNA level above 2,000 IU/mL. In conclusion, the newly developed real-time PCR-based assay Alinity m HBV assay can correctly detect HBV DNA in DBS, especially for patients with blood HBV DNA levels above 2,000 IU/mL, and also accurately quantify HBV DNA in plasma samples. IMPORTANCE Hepatitis B virus is one of the most prevalent blood-borne viruses affecting the liver and causing acute and chronic hepatitis. Only a small proportion of people with HBV infection are diagnosed. HBV DNA measurement is critical in clinical practice for the diagnosis and treatment decisions of patients requiring antiviral therapy. Dried blood spot (DBS) collection provides a simple, practical, and acceptable alternative to venous blood collection, especially in community settings. We have demonstrated high sensitivity and specificity for HBV DNA detection in DBS compared to plasma samples, especially when using clinically relevant cutoffs of 2,000 and 20,000 IU/mL. Results support the use of DBS in community-based settings.

Effectiveness of the HCV blood screening strategy through eighteen years of surveillance of HCV infection in blood donors in France.

BACKGROUND: The question of maintaining blood screening based on both Hepatitis C virus (HCV) infection antibodies (Ab) and Nucleic Acid Testing (NAT) has been raised in several countries. The French blood donor surveillance database was used to address this issue. MATERIALS AND METHODS: In France, HCV-NAT was implemented in mini pools (MP) in 2001 and in individual testing (ID) in 2010. HCV-positive donations are further investigated including detection of RNA with an alternative polymerase chain reaction assay: Amplicor HCV v2.0 (Roche; LOD95 50 IU/mL) from 2001 to 2006 and CobasTaqMan (CTM) HCV 2.0 assay (Roche; LOD95 9.3 IU/mL) since 2007. RESULTS: From 2001 to 2018, 3,058/48.8 million donations were confirmed HCV positive: 64.4% were Ab+/NAT+, 35.1% Ab+/NAT- and 0.5% Ab-/NAT+. From 2001 to 2018, the NAT yield decreased from 0.65 per million donations to 0, and NAT+ donations dropped from 77% to 46% of the total of HCV donations. 2,491/3,058 were further tested for HCV-RNA: 1,032 (816 NAT+, 216 NAT-) with Amplicor and 1,459 (897 NAT+, 562 NAT-) with CTM. Four (3 MP and 1 ID-NAT, 0.5%) of the 778 NAT negative donations had low viral loads. DISCUSSION: The decline in HCV-NAT yield cases raises the question of the relevance of NAT. Conversely, the increase in Ab+/NAT-donors, suggesting a growing number of resolved infections, argue for Ab discontinuation. In our experience, at least 0.5% of Ab+/NAT-donations had low RNA level when retested. Although the risk of viral transmission by such donations is probably low, the uncertainty associated with their infectivity goes against the removal of Ab in blood screening in our country.

No Evidence of Hepatitis C Virus (HCV)-Assisted Hepatitis D Virus Propagation in a Large Cohort of HCV-Positive Blood Donors.

A study reported in 2019 showed that hepatitis C virus (HCV) could help disseminate hepatitis D virus (HDV). To test this finding, 2123 plasma samples positive for anti-HCV antibody were screened for anti-HDV antibodies, and HDV-RNA was searched for in samples positive for anti-HDV antibody. Of 41 samples (1.9%) that tested positive for anti-HDV antibody, 27 (65.9%) were positive and 14 (34.1%) negative for antibody to hepatitis B core antigen (anti-HBc). Anti-HDV antibodies were significantly more present in samples positive for anti-HBc (6.21% vs 0.8% in negative samples; P < .001) and in samples negative for HCV RNA (2.9% vs 1.5% for positive samples; P = .03). Serological ratios were significantly higher in samples positive for anti-HBc (P < .01). No anti-HDV-positive sample was HDV RNA positive. In conclusion, this study found no evidence suggesting a role for HCV in HDV dissemination in humans.

Transfusion of HIV-infected blood products despite highly sensitive nucleic acid testing.

BACKGROUND: In France, the risk of HIV transmission by transfusion was reduced by implementing pooled nucleic acid testing (NAT) in 2001 and individual NAT in 2010. We report here the first case in France of transfusion of human immunodeficiency virus (HIV)-infected blood donated during HIV pre-ramp-up phase that tested individual NAT negative. METHODS: Blood donations are screened for HIV antibodies and HIV RNA (ProcleixUltrio, Grifols; limit of detection at 95%, 23 copies/mL). When a repeat donor tests positive for HIV, a repository sample from the previous donation is tested with the Cobas Taqman HIV-1 test (CTM, Roche; limit of detection at 95%, 17 copies/mL). RESULTS: In August 2017, a 57-year-old male repeat donor was screened positive for HIV antibodies and RNA (plasma viral load, 11,599 copies/mL). The previous donation had tested negative with Ultrio in March 2017 but was positive with an unquantifiable plasma viral load when tested with CTM. Sequencing showed no mismatch between Ultrio primers/probes and the target sequence. HIV transmission was excluded by lookback studies in the recipient of platelets, which had been pathogen reduced, but not in the recipient of RBCs due to premature death. CONCLUSION: This case demonstrates that the risk of contaminated donations due to the early HIV infection phase going undetected by highly sensitive NAT is real but exceptional. The absence of transmission to the platelets recipient could be due to the very low viral inoculum and/or to the efficacy of the viral inactivation. This case also highlights the additional value of a systematic donation archiving and the importance of donor education and predonation selection.