These and other studies have concluded that the core pro-inflammatory cytokines TNFα, IL-1β, IL-6, G-CSF, GM-CSF as well as the chemokines MCP-1, IP-10 and MIP1α are elevated in patients with COVID-19, with higher levels in those patients who are critically ill compared with those with less serious illness [142]. Here, CCL2 is linked to COVID-19.