IFNA1 and infection: The early increase in the production of IFN and the down-regulation of pro-inflammatory cytokines at late times post-infection with SARS-CoV-2-Δ8 led to a partial attenuation (Fig. 2, 3, 4 and 6), suggesting a protective effect, as previously described for the early administration of IFN in SARS-CoV- (37) and MERS-CoV- (58) infected mice.