West Nile virus (WNV) can be transmitted by transfusion of blood products, and can become a threat to transfusion safety. WNV Kunjin strain (WNVKUN) is endemic across parts of Australia; however, human infection is believed to be infrequent and is often associated with relatively minor symptoms. A virulent strain, closely related to WNVKUN (termed WNVNSW2011) was recently identified as the etiologic agent of encephalitis in Australian horses.
The aim of this project was to investigate whether a commercially available WNV blood screening assay can detect different strains of WNVKUN, including the virulent WNVNSW2011, in human blood donor samples.
Plasma samples were spiked with four different strains of WNVKUN, as well as a prototype WNV strain, at high, medium, and low viral loads. Spiking was confirmed with real-time reverse transcription–polymerase chain reaction (RT-PCR), before testing with the Procleix WNV transcription mediated amplification (TMA) blood screening assay (Grifols).
All WNV strains used were detectable by RTPCR and by WNV TMA. Therefore, the study experimentally demonstrated that a commercially viable WNV blood screening assay can detect different strains of WNVKUN. This is very import in preventing the blood transmission of WNV.