West Nile virus testing experience in 2007: evaluation of different criteria for triggering individual-donation nucleic acid testing.

Background: In 2007, clients served by Blood Systems Laboratories used variable approaches for triggering West Nile virus (WNV) RNA individual-donation (ID) nucleic acid testing (NAT). These included two minipool (MP) NAT-reactive donations and a greater than 1:1000 rate in a 7-day interval (primary trigger), criteria based on one MP-NAT-reactive donation when there was WNV activity in overlapping and/or adjacent geographic areas (neighbor trigger), or zero MP-NAT-reactive donation (self-trigger).

Study Design And Methods: The Procleix WNV assay was used in either a 16-sample MP or an ID format.