A previous study reported that interferon γ-induced protein 10, monocyte chemotactic protein-3, IL-1 receptor antagonist, IL-6, IL-8, IL-10, sIL-2R, IL-1®, IL-4 and IL-18 might be involved in the major biological processes of severe COVID-19 patients and reflect the level of systemic hyperinflammatory state [50]. Here, IL6 is linked to COVID-19.