The cell types harboring the highest proportions of SARS-CoV-2 RNA+ cells represent the same cell types uniquely expanded or induced within COVID-19 participants, such as KRT24highKRT13high secretory cells, AZGP1high goblet cells, and IFN-responsive ciliated cells, and contain the highest abundances of ACE2-expressing cells (Figure 5E). This evidence concerns the gene IFNA1 and COVID-19.