Circulating IL-6, IL-18, IFN-γ, IL-15, TNFα, IL-1α, IL-1β, IL-2, G-CSF, IP-10 (or CXCL10), MCP1 (or CCL2), MCP3 (CCL7) and MIP-1α (CCL3) are over-expressed in patients with moderate or severe COVID-19 (82). Here, CCL3 is linked to COVID-19.