Recent reports have also found increased neutrophil counts and decreased lymphocyte counts associated with COVID-19 [29, 30] Lymphocytopenia could explain the effect of SARS-CoV-2 on T lymphocytes, mainly on CD4+ T cells and CD8+ T cells, resulting in a decrease in lymphocyte numbers and IFN-γ production [19, 30]. This evidence concerns the gene IFNG and COVID-19.