Another observation supporting the importance of inflammatory cytokines in COVID-19 was that patients with interleukin-8 > 35 pg/ml had significantly lower levels of blood oxygen saturation (median 94%; IQR 92; 96), compared with patients who had interleukin-8 < 35 pg/ml (median 96%; IQR 93; 97; p < 0.05). This evidence concerns the gene CXCL8 and COVID-19.