IFNA2 and infection: Coherently with our findings, in the more recent and larger transcriptome study (24) of cells from NP swabs, the most striking difference by age in gene expression signature was observed in the IFN-α signaling that was pre-activated in not-infected children and only slightly induced after SARS-CoV-2 infection; adults (not differentiated by age in that study) showed very low basal levels of IFN-α related genes but these were strongly activated upon infection (24).