In another study, severe COVID-19 patients had a lower peripheral lymphocyte count, natural killer cells, high CRP levels, and pro-inflammatory cytokines IL6, IL8, TNFα, IL2-R, IL1-β, etc. This unusual cytokine production may destroy host immune responses, i.e., low lymphocyte infiltration into infected lungs and multiple organ damage (192). This evidence concerns the gene IL2RA and COVID-19.