Susceptibility of WT or IFNAR-/- mice to parental JEV and Rluc-JEV. (A) Survival curve of mice infected with viruses. WT or IFNAR-/- mice (n=6 or 7) were injected via the footpad with of 107 PFU of Rluc-JEV or the parental JEV, and monitored daily for 15 days to assess morbidity and mortality. Rluc-JEV-WT, WT mice infected with Rluc-JEV; JEV-WT, WT mice infected with parental JEV; Rluc-JEV-IFNAR-/-, IFNAR-/- mice infected with Rluc-JEV; JEV-IFNAR-/-, IFNAR-/- mice infected with parental JEV. The data are representative of at least three independent experiments. (B) Viral load in tissues of WT mice infected with viruses. Groups of WT mice (n=2) were injected via the footpad with of 106 PFU of Rluc-JEV or the parental JEV. At 72 h.p.i., brains and intestines were collected, homogenized, and subjected to virus titration by qRT-PCR. The dotted line indicates the limit of detection. The data are representative of at least three independent experiments.