New atypical epidemiological profile of parvovirus B19 revealed by molecular screening of blood donations, France, winter 2023/24.

In France, blood donations are tested in pools of 96 samples for parvovirus B19 (B19V) DNA to discard plasma for fractionation when it contains high viral loads. Between January 2015 and March 2024, B19V-positive donations decreased during the COVID-19 pandemic, followed by a strong rebound in 2023 and unusually high circulation during winter 2023/24 (ca 10 times higher December 2023-March 2024 vs the pre-pandemic period). Variations over time are probably related to measures implemented to limit SARS-CoV-2 spread.

Low rate of RNAemia in blood donations collected during the first wave of COVID-19 in France.

BACKGROUND: To investigate the transmission of SARS-CoV-2 via blood, we conducted retrospective molecular screening in blood donated during the first pandemic peak in the two French regions with the highest community transmission. METHODS: Archived plasma samples randomly selected from donations collected between March 23 and 29, 2020, in Eastern and Northern regions of France were tested for SARS-CoV-2 RNA in minipools of 4 donations (MP4) using the Grifols ProcleixSARS-CoV-2 assay. Reactive MP4 and the four corresponding plasmas were further tested with alternative RT-PCRs and sequencing. Testing for SARS-CoV-2 antibodies and in vitro infectivity in cell culture were also performed. RESULTS: Among the 2818 MP4 (corresponding to 9672 donations) tested for viral RNA, 5 were weakly reactive. Among the 20 plasmas included in these five MP4, one presented low-level reactivity with RT-PCRs and Procleix SARS-CoV-2 and was confirmed on sequencing. The estimated prevalence was 1.03/10,000 (95% CI 0-3.1). The 20 plasmas were antibody nonreactive and none of them showed cytopathic effects in cell culture. When recalled, the index-donor declared having had symptoms compatible with SARS-CoV-2 infection a few days after donation. The two immunocompromised recipients transfused with red blood cells and an inactivated pooled platelet product did not develop COVID-19. CONCLUSION: Our results indicated a low prevalence of SARS-CoV-2 RNA in the plasma of asymptomatic blood donors during the pandemic peak and no evidence of infectivity in vivo and in vitro. The transfusion risk remains theoretical and does not justify the implementation of SARS-CoV-2 NAT for blood donations.

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.

Hepatitis A: an epidemiological survey in blood donors, France 2015 to 2017.

Since mid-2016, hepatitis A virus (HAV) outbreaks, involving predominantly men who have sex with men (MSM), have affected countries in Europe and overseas. In France, HAV screening of blood donations in 2017 revealed a HAV-RNA prevalence ca fivefold higher than during 2015-16 (4.42/106 vs 0.86/106; p = 0.0005). In 2017, despite a higher male-to-female ratio (5.5 vs 0.7) and the identification of MSM-associated outbreak strains, only one of 11 infected male donors self-reported being a MSM.

Comparison of the analytical and operational performance of two viral nucleic acid test blood screening systems: Procleix Tigris and cobas s 201.

BACKGROUND: The operational and analytical performance of two automated triplex hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV) nucleic acid test (NAT) systems were compared in four screening laboratories of the French Blood Service. STUDY DESIGN AND METHODS: Two laboratories evaluated the Procleix Tigris system (Chiron/Gen-Probe) in individual donation (ID) format and two sites used the cobas s 201 system (Roche Molecular Systems) on minipools (MPs) of six donations. The analytical sensitivity, the specificity, and operational performance were compared. RESULTS: The ID to MP-NAT relative sensitivity factors in standard dilution panels of different genotypes varied between 8.7 and 21.9 for HCV RNA, 6.7 and 14.8 for HIV RNA, and 0.71 and 11.6 for HBV DNA. Tigris was 800-fold more sensitive than cobas s 201 (1:6) for a HIV group O sample, but did not detect the HIV-2 sample picked up by cobas s 201 with equal sensitivity as the HIV-1 group M samples. The specificity of both NAT systems after initial screening of 10,520 donations with Tigris and 1444 test pools on s 201 was 99.9 percent for both systems, but reached 100 percent after the repeat and pool resolution test algorithms. A higher throughput of the pool test protocol on cobas s 201 became apparent when the daily workload was more than 400 donations. CONCLUSIONS: Tigris ID-NAT format was significantly more sensitive than cobas s 201 MP-NAT in detecting HCV RNA and HIV RNA dilution panels, but despite the 1:6 dilution factor in s 201 the difference in sensitivity was not significant for some of the HBV genotype panels. Both NAT systems demonstrated acceptable operational performance, but for routine use further improvement in system reliability is desirable.

Sensitivity of two hepatitis B virus, hepatitis C virus (HCV), and human immunodeficiency virus (HIV) nucleic acid test systems relative to hepatitis B surface antigen, anti-HCV, anti-HIV, and p24/anti-HIV combination assays in seroconversion panels.

BACKGROUND: Accurate determination of the infectious window period (IWP) that remains with individual-donation (ID) or minipool (MP) NAT compared to those with serology assays is essential for residual risk estimations. STUDY DESIGN AND METHODS: The relative sensitivity of the Procleix Tigris system (Gen-Probe/Chiron) used in ID-NAT format and cobas s 201 (Roche Molecular Systems) applied in 1:6 diluted samples to mimic six-minipool (MP6) nucleic acid test (NAT) was assessed by quadruplicate testing of five seroconversion panels per marker. A mathematical analysis based on the log-linear increase of viremia in the ramp-up phase, as established with bDNA 3.0 assays enabled estimation of the IWP for human immunodeficiency virus (HIV) and hepatitis B virus (HBV) assays. RESULTS: The mean IWPs were Tigris HIV RNA 5.5 days, s 201 (1:6) HIV RNA 7.4 days, GenScreen Plus p24/anti-HIV 17.8 days, PRISM anti-HIV 19.0 days, Tigris HBV DNA 20.6 days, s 201 (1:6) HBV DNA 22.6 days, Bio-Rad hepatitis B surface antigen (HBsAg) 37.8 days, and PRISM HBsAg 35.5 days. At estimated 50 percent NAT seroconversion rates, s 201 (1:6) and Tigris showed mean window-period reduction times (WPRTs) of 30.5 to 35.5 days to hepatitis C virus antibody (anti-HCV) assays, 10.4 to 13.5 days to anti-HIV, or combination p24/anti-HIV assays and 12.8 to 17.2 days to HBsAg assays. CONCLUSIONS: Tigris ID-NAT detected HIV RNA 2 days earlier than s 201 MP6-NAT, but the difference in sensitivity between the two NAT systems was not significant in HBV seroconversion panels. Insufficient seroconversion samples were available for reliable modeling of WPRT in early HCV infection, but 1.4 to 2.0 days could be predicted by translating analytical sensitivity data. Both multiplex NAT systems demonstrate significant WPRTs compared to (combined) antigen and antibody assays.

A revised method for estimating hepatitis B virus transfusion residual risk based on antibody to hepatitis B core antigen incident cases.

BACKGROUND: To take into account the transient nature of hepatitis B virus (HBV) antigenemia, the calculation of HBV residual risk (RR), based on the incidence/window period model, is adjusted by a correction factor that adds uncertainty to the RR estimates. STUDY DESIGN AND METHODS: This new method to estimate the RR for HBV is a weighted sum of the RR derived from hepatitis B surface antigen (HBsAg) incident cases and the one derived from antibody hepatitis B core antigen (HBc) incident cases. An anti-HBc incident case was defined as a donation from a blood donor who had made at least one anti-HBc-negative donation followed by a donation that was found positive with two different assays within a 3-year period and positive for at least one of the following markers: 1) antibody to hepatitis B e antigen or hepatitis B e antigen, 2) anti-HBc immunoglobulin M, 3) HBV DNA, 4) hepatitis B surface antibody without HBV vaccination history, or 5) HBV DNA retrospectively found in the previous donation. Five overlapping 3-year study periods between 2000 and 2006 were analyzed. RESULTS: The HBV RR estimated with the classical method ranged from 1.51 (2000-2002) to 0.69 per million donations in 2004 through 2006 with a decrease in 2002 through 2004 due to only two HBsAg incident cases reported in this period. By applying the revised model, the HBV RR ranged from 1.06 (2000-2002) to 0.49 per million donations (2004-2006), with a regular decrease. CONCLUSION: The new presented model provides HBV RR estimates that do not statistically differ from those obtained with the classical model; however, it provides more accurate data, especially in low endemic areas where the HBsAg incidence is low.

[Future technological evolutions in blood donation qualification]. / Les évolutions technologiques dans la qualification biologique des dons de sang.

In the past decades, blood donation screening contributed significantly to blood safety improvement, thanks to the increasing performances of serological and nucleic acid testing (NAT) assays, as well as the evolution of automated systems technology. The rapid pace of NAT development can be clearly seen to extend into the future. NAT for additional viruses as well as the use of new automated systems for individual donation or smaller mini-pool testing, with multiplex assays, is currently debated. However, few added benefit is expected for blood safety from such developments, while cost-effectiveness appears to be poor. The next step in laboratory automation will probably be the implementation of robotic pre- and post-analytical procedures. In this article we review the potential future evolutions of screening technologies in blood qualification platforms, particularly those derived from nanobiotechnologies. DNA microarrays, Lab-On-Chips, biosensors and nanoparticles (quantum dots) will probably play a major role in the coming decade.

Flexible automated platform for blood group genotyping on DNA microarrays.

The poor suitability of standard hemagglutination-based assay techniques for large-scale automated screening of red blood cell antigens severely limits the ability of blood banks to supply extensively phenotype-matched blood. With better understanding of the molecular basis of blood antigens, it is now possible to predict blood group phenotype by identifying single-nucleotide polymorphisms in genomic DNA. Development of DNA-typing assays for antigen screening in blood donation qualification laboratories promises to enable blood banks to provide optimally matched donations. We have designed an automated genotyping system using 96-well DNA microarrays for blood donation screening and a first panel of eight single-nucleotide polymorphisms to identify 16 alleles in four blood group systems (KEL, KIDD, DUFFY, and MNS). Our aim was to evaluate this system on 960 blood donor samples with known phenotype. Study data revealed a high concordance rate (99.92%; 95% CI, 99.77%-99.97%) between predicted and serologic phenotypes. These findings demonstrate that our assay using a simple protocol allows accurate, relatively low-cost phenotype prediction at the DNA level. This system could easily be configured with other blood group markers for identification of donors with rare blood types or blood units for IH panels or antigens from other systems.

Failure and success of HIV tests for the prevention of HIV-1 transmission by blood and tissue donations.

French blood banks recently implemented nucleic acid testing (NAT) of all blood donations to reduce the risk of HIV transmission during the pre-seroconversion period. For tissue donation, HIV infection screening relies on HIV p24 antigen and anti-HIV-1 and 2 antibody detection. In this report, two related cases of infectious donations are described from a cornea donor during the preseroconversion window who was infected by an HIV antibody and NAT negative blood donor. After investigation, the blood donor was found to be herself in the preseroconversion window. Two months after donation, she was found to be HIV positive. The residual risk of HIV infectious blood donations since NAT has been introduced is estimated to be lower than one out of 2.5 millions. Individual NAT instead of minipool testing would not increase significantly the blood transfusion safety. In contrast, introduction of NAT should be considered to increase tissue donation safety as soon as such screening will be possible technically.