Background and objectives: In order to reduce the potential for transmission of hepatitis C virus (HCV) from an RNA-positive, anti-HCV-negative blood donation, the National Blood Service (NBS) introduced nucleic acid amplification technology (NAT) testing for HCV in England and Wales. The objective of this study was to develop an automated assay using commercial components for the detection of HCV RNA in blood donations for transfusion.
Materials and methods: The Qiagen QIAamp 96 'Viral RNA' and 'Virus' BioRobot kits for HCV RNA extraction, and the Roche COBAS HCV Amplicor v2.0 and AmpliScreen v2.0 assays for polymerase chain reaction (PCR) amplification and detection, were investigated.
Results: QIAamp technology and the BioRobot 9604 allow automation of the viral RNA extraction process. By combining the automated silica-membrane based QIAamp 96 Virus extraction and automated reverse transcription-polymerase chain reaction (RT-PCR) set-up with COBAS HCV AmpliScreen v2.0 amplification and detection it is possible to achieve a 95% detection level for HCV of 12.8 IU/ml. Cross-contamination studies have shown that use of the BioRobot 9604 does not pose a detectable contamination risk. Between 1999 and 2001, approximately 6.8 x 106 donations were tested in England and Wales, of which only four were found to contain RNA without anti-HCV.
Conclusions: This combination of methods results in an assay with a high sample throughput, little 'hands-on' time and fast turnaround time that is also sufficiently sensitive to allow testing of pools of up to 96 samples at a time. These methods have been successfully introduced into routine use within the NBS for release of blood components with a shelf-life of longer than 24 h.