KRT18 and viral encephalitis: Although K18-hACE2 mice can suffer fatal viral encephalitis from the neuroinvasion of SARS-CoV-2 (61) and the metabolites of ATV006 were not detectable in the mouse brain, ATV006 could effectively prevent the death of K18-hACE2 mice infected by SARS-CoV-2 Delta variant in the prophylactic model.