Increased IFN signature is consistent with the transcriptional signatures reported in other COVID studies and correlates with the severity of COVID-19 (4, 11, 48, 49) and suggests that IFN-responsive genes at 2 dpi (early stage of SARS-CoV-2 infection with peak viral titer in ferret model) could be advantageous in clearing SARS-CoV-2 (12). Here, IFNA1 is linked to COVID-19.