Interlaboratory study to evaluate the performance of laboratories involved in West Nile virus RNA screening of blood and blood components by nucleic acid amplification testing in Italy.

Background: An Italian interlaboratory study was run in 2010 to assess the performance of Blood Transfusion Services in detecting the genome of West Nile virus (WNV) in plasma.

Materials And Methods: Each laboratory received a panel of samples containing four samples negative for WNV and six positive samples with a nominal viral concentration close to or below the 95% detection limit of two commercially available nucleic acid amplification tests (NAT) for WNV, the PROCLEIX® WNV kit and the Cobas® TaqScreen West Nile Virus kit.

Results: Ten laboratories took part in the study. All correctly identified the positive samples with a viral concentration above the 95% detection limit. No pre- or post-analytical errors were observed.

Conclusions: The interlaboratory study run in 2010 allowed participants to assess the performance of the NAT methods applied in their seasonal routine screening of blood donations.