IL9 and viral infectious disease: Cytokine storm is a term applied to maladaptive cytokine release in response to viral infection, leading to elevated systemic levels of cytokines and chemokines, including: interleukin 1α (IL-1α); tumor necrosis factor alpha (TNF); interleukin 7 (IL-7); vascular endothelial growth factor (VEGF); interleukin 8 (IL-8); interferon gamma (IFN-γ); interleukin 9 (IL-9); interleukin 10 (IL-10); monocyte chemoattractant protein-1 (MCP-1); and others [6].