Consistent with the observed clinical phenotype, stat1loxP/loxP/Vav-cre, but not WT and stat1loxP/loxP/Alb-cre mice, displayed a sharp increase in YFV-17D RNA in the serum 3 days post infection followed by a decline in viremia between days 3 and 7 post infection (Fig. 3d). Here, VAV1 is linked to infection.