Performance evaluation of the PROCLEIX® West Nile virus assay on semi-automated and automated systems

• Published in: Journal of medical virology Vol. 79; no. 9; pp. 1422 - 1430
• Main Authors: Linnen, Jeffrey M., Deras, Michael L., Cline, Janice, Wu, Wen, Broulik, Amy S., Cory, Robin E., Knight, James L., Cass, Michelle M.J., Collins, Cynthia S., Giachetti, Cristina
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 01.09.2007; Wiley-Liss
• Subjects: Biological and medical sciences; Biological Assay; donor blood screening; Fundamental and applied biological sciences. Psychology; Human viral diseases; Humans; Infectious diseases; Medical sciences; Microbiology; Miscellaneous; NAT; Nucleic Acid Amplification Techniques - methods; Reproducibility of Results; Sensitivity and Specificity; TMA; Viral diseases; Virology; West Nile virus; West Nile virus - isolation & purification; Virus; Performance evaluation; NAT; Screening; donor blood screening; West Nile virus; TMA; Japanese encephalitis group virus; Flaviviridae; Flavivirus; Blood donor
• ISSN: 0146-6615; 1096-9071
• DOI: 10.1002/jmv.20930

The PROCLEIX® West Nile virus assay (WNV assay) is a qualitative nucleic acid test based on transcription‐mediated amplification (TMA). The assay was used under an investigational protocol in the United States to screen blood donations for West Nile virus (WNV) RNA starting in the summer of 2003, and was licensed by the FDA in December 2005 for use on the PROCLEIX System, also known as the enhanced semi‐automated system (eSAS). Performance characteristics for the assay were determined on both eSAS and the fully automated PROCLEIX® TIGRIS® (TIGRIS) System. Detection of both lineage 1 and lineage 2 WNV was demonstrated on both systems. For lineage 1, the 95% detection limit was 8.2 copies/ml for eSAS and 9.8 copies/ml for the TIGRIS system. For lineage 2, ≥95% detection was seen at ≥30 copies/ml on both systems. The overall specificity of the assay was >99.9% in fresh and frozen plasma specimens. Reproducibility studies on the TIGRIS system yielded ≥99.1% agreement with expected results for the 3‐member panel tested (0, 30, and 100 copies/ml). The WNV assay exhibited robust performance in cadaveric specimens and specimens representing various donor and donation conditions, including specimens from different plasma collection tubes that were subjected to multiple freeze/thaw cycles; specimens with elevated levels of endogenous substances; specimens containing other viruses and microorganisms; and specimens from patients with autoimmune and other diseases. Overall, these studies demonstrate high sensitivity, specificity, and reproducibility of the WNV assay on both the semi‐automated and automated systems. J. Med. Virol. 79:1422–1430, 2007. © 2007 Wiley‐Liss, Inc.