Indeed, because Ccr5+/+ and Ccr5−/− mice began to show clinical signs, such as neurological disorders, at 3–5 dpi, which is before functional adaptive immune responses were fully induced, the JE model used in this study appeared to have more acute and rapid progression than that in a previous study, in which clinical signs were observed at 8–10 dpi [17]. This evidence concerns the gene CCR5 and Japanese encephalitis.