CCL7 and COVID-19: Previous studies reported that COVID-19 is frequently associated with a massive production of 14 cytokines including IFN-γ, IL-1RA (IL1RN), IL-2RA, IL-6, IL-10, IL-18, HGF, MCP-3 (CCL7), MIG (CXCL9), M-CSF (CSF1), G-CSF (CSF3), MIG-1a (CCL3), CTACK (CCL27), and IP-10 (CXCL10) (24).