(A) Groups of IFN-α/β/γR KO mice (5–6 weeks old) were intraperitoneally infected with DV3P12/08 at doses ranging from 2 × 106 to 2 × 102 focus-forming units (FFU) or (B) subcutaneously infected with 2.6 × 106 FFU of DV3P12/08 and survival monitored. (C) Groups of IFN-α/βR KO mice (either 5 weeks old or 11 weeks old) were intraperitoneally infected with 1.3 × 107 FFU of DV3P12/08 and survival was monitored. (D) IFN-α/β/γR KO mice (5–6 weeks old) were intraperitoneally infected with 2 × 106 of DV3P12/08, sacrificed at Day 5 p.i. under anesthesia, and perfused extensively with PBS. Virus copy numbers in the spleen, liver, kidney, thymus, lung, brain, peritoneal exudate cells (PEC), bone marrow (BM), upper (U) small intestine, lower (L) small intestine, large intestine, and serum were then measured by qRT-PCR. Bars indicate the mean value. Each symbol represents an individual mouse.