Our results demonstrated that infection with each of the three Asian/American-subtype strains used in this study was not lethal to IFNAR1-KO mice, whereas we previously demonstrated that infection with the African-lineage MR766 strain was lethal when the mice were inoculated with a lower infectious titer (1 × 102 PFU) of strain MR766 [34]. This evidence concerns the gene IFNAR1 and infection.