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This study was conducted to analyse the usefulness of hepatitis C virus (HCV) core antigen tests for the confirmation of HCV infection in a donor presenting as nucleic acid amplification technology (NAT) positive but negative for antibodies to HCV (anti-HCV). Blood donations were screened, in parallel, for anti-HCV using the Abbott PRISM HCV Chemiluminescent immunoassay (ChLIA) and an ‘in-house’ HCV NAT (pools of up to 95 donations). An HCV NAT-positive antibody-negative donor was identified. Twelve follow-up samples were obtained and tested with various HCV antigen (including the recently marketed Trak-C second-generation assay) and HCV antibody assays. The single HCV NAT-positive, antibody-negative donation was identified from 1 117 681 donations screened in the 4-year period, July 1999 to June 2003. The index donation was positive by Ortho HCV core antigen enzyme immunoassay (EIA) and Ortho Trak-C (second-generation HCV core antigen EIA). An archive sample, taken 127 days prior to the index donation, was negative for all HCV markers. Subsequent samples demonstrated a loss of reactivity in the Ortho HCV core antigen EIA and reduced activity in the Ortho Trak-C until day 69. Immunoblot (Ortho RIBA-3) and HCV PRISM became positive on day 62, whilst Ortho HCV ELISA was not positive until day 132 or Biorad HCV ELISA until day 160. An alternative immunoblot (Innogenetics Innolia III) was positive from day 55. RNA levels fluctuated considerably during the follow-up period, being completely undetectable by routine screening methods at the time-point around seroconversion; subsequently, antibody was detected using all assays investigated. This HCV-converting blood donor provided a unique panel of samples for using to assess current (and future) HCV assay systems. The overall test results led to the conclusion that individual HCV antigen testing should not be considered as equivalent to HCV NAT minipool screening. Trak-C antigen testing may be considered as a suitable confirmatory assay for isolated HCV NAT reactivity. [ABSTRACT FROM AUTHOR]

Borna disease virus (BDV) can infect a wide range of vertebrate species causing neurological disease. In order to ensure the safety of blood supplies, it is essential to monitor blood for emerging pathogens. One-hundred individual white cell pellets and pools representing 25 000 plasma donations from human blood were screened for BDV by reverse transcription–polymerase chain reaction (RT–PCR). BDV RNA was not detected in any of the samples. The results indicate that BDV is not widely spread in the UK human population and does not represent a risk as a transfusion-transmitted agent. [ABSTRACT FROM AUTHOR]

Objective: To investigate the infectivity for hepatitis C virus (HCV) of intravenous anti-D immunoglobulin batches manufactured in Ireland between 1991 and 1994., Methods: Women who had received anti-D manufactured between 1991 and 1994 were screened for serological markers of HCV infection and for the presence of HCV RNA by RT-PCR amplification and virus genotyping., Results: 44 women exposed to anti-D manufactured between 1991 and 1994 were polymerase chain reaction positive for HCV RNA, 19 of whom were infected with genotype 3a virus shown by phylogenetic analysis of the NS5B gene to be closely related to that from the single implicated donor., Conclusions: Anti-D manufactured in 1991-1994 transmitted infection of HCV genotype 3a. The prevalence of HCV-specific antibody in anti-D recipients was relatively low (0.59%), consistent with the low level of virus RNA in these anti-D batches.