Automated Test for West Nile Virus

A West Nile virus (WNV) assay is designed for use on a fully automated nucleic acid testing (NAT) system that allows blood centers to test individual blood samples with greater operator efficiency.

The WNV assay is used on the Procleix Tigris system, a high-throughput system developed by Gen-Probe (San Diego, CA, USA) and Chiron Corp. (Emeryville, CA, USA). Procleix assays and systems incorporate amplified NAT technology to detect viral RNA and DNA in donated blood and plasma during the early stages of infection, when those infectious agents are present but cannot be detected by immunodiagnostic tests. The Procleix WNV assay is being introduced into blood testing centers as an investigational new drug in regions with high prevalence of WNV. The assay has detected 137 WNV-infected blood donations since May 2004.

Blood centers using the Procleix WNV assay and experiencing a large number of WNV-positive donations have developed algorithms to determine when testing should be moved from pools of 16 to individual donor testing, which offers the best opportunity to detect the virus. Testing is planned for epidemic areas to improve the efficiency of high-volume testing. A clinical trial for the assay is currently being conducted at five U.S. blood centers to confirm the test's sensitivity, specificity, and reproducibility on a semi-automated instrument platform. According to the U.S. Centers for Disease Control and Prevention (Atlanta, GA, USA), 843 human cases of WNV infection have been reported for the current mosquito season as of August 24, 2004.

"The Procleix Tigris system is the first fully automated NAT system available for blood screening, and its use with the Procleix WNV assay will allow for maximum sensitivity by enabling individual donor testing and would bring a new level of quality assurance in detecting potential transfusion-transmitted viruses like WNV,” said Andrew Heaton, M.D., vice president and chief medical officer, Chiron Blood Testing.





Related Links:
Chiron Corp.
Gen-Probe