Our scRNA-seq analysis showed that, compared with the HCs,ERS patients who recovered less than 7 days have a lower ratio of T and NK cells,and these patients’ T cells express higher levels of inflammatory genes, such asJUN, FOS, JUNB, and KLF6. Several studies have reported that lymphopenia is a prominentpart of SARS-CoV2 infection and lymphocyte counts are useful in predicting theseverity and clinical outcomes35–37. This evidence concerns the gene FOS and lymphopenia.