To evaluate this, IRF-3−/− and wild-type mice were infected with 102 PFU of WNV via a footpad route, and viral burden was measured by fluorogenic quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) or viral plaque assay at days 1, 2, 4, 6, 8, and 10 post infection in blood, peripheral organs (draining lymph nodes, spleen, and kidney), and the CNS (brain and spinal cord). Here, IRF3 is linked to infection.