Survival and Virologic Analysis for Wild-Type and IRF-3^−/− C57BL/6 Mice

<div><p>(A) Eight- to twelve-week-old mice were inoculated with 10² PFU of WNV by footpad injection and followed for mortality for 21 d. Survival differences were statistically significant (<i>n</i> = 20, IRF-3^−/−; and <i>n</i> = 20, wild-type mice; <i>p</i> < 0.0001).</p><p>(B–G) Viral burden in peripheral and CNS tissues after WNV infection. WNV RNA in (B) serum and (C) draining lymph node, and infectious virus in the (D) spleen, (E) kidney, (F) brain, and (G) spinal cord were determined from samples harvested on days 1, 2, 4, 6, 8, and 10 using qRT-PCR (B, C) or viral plaque assay (D–G). Data is shown as viral RNA equivalents or PFU per gram of tissue for ten to 12 mice per time point. For all viral load data, the solid line represents the median PFU per gram at the indicated time point, and the dotted line represents the limit of sensitivity of the assay. Error bars indicate the standard deviations (SD). Asterisks indicate values that are statistically significant (*, <i>p</i> < 0.05; **, <i>p</i> < 0.005; ***, <i>p</i> < 0.0001) compared to wild-type mice.</p>