In contrast, at the later phase of infection (48 and 72 hpi), RNA levels for WNVNY99 were increased (Figure 1h), which likely explains the increased induction of IFNβ (Figure 3a), OAS1 (Figure 3b) and MxA mRNAs (Figure 3c), as well as a significant increase in induction of proinflammatory cytokines TNFα (48 hpi p < 0.05, Figure 3d) and IL-6 (72 hpi p < 0.05, Figure 3e). This evidence concerns the gene IFNB1 and infection.