ISG15 and infection: We observed approximately 0.5 to 1-log fold greater expression of ISG15, EIF2AK2, OAS1, IFNA4, and IFNB1 in the lungs of rWSN-GH-NS1-Y84F infected mice on days 1 and 3 post-infection compared with the lungs of rWSN-GH-NS1-wt infected mice (Figure 9D).