IL6 and COVID-19: Similar to the changes in SARS and MERS, in COVID-19, higher plasma levels of cytokines including IL-6, IL-2, IL-7, IL-10, granulocyte-colony stimulating factor, interferon-γ (IFN-γ)–inducible protein, monocyte chemoattractant protein, macrophage inflammatory protein 1α, and TNF-α were found in ICU patients, which implied that a cytokine storm occurred (7, 9) and related to the severity and prognosis of the disease.