In the subsequent hyper-inflammatory phase, severe COVID-19 cases dramatically increase the levels of IL-2, IL-6, IL-7, IL-10, IP-10, CCL2 (also known as monocyte chemoattractant protein-1/MCP1), TNF-α, macrophage inflammatory protein-1α (MIP1α), and G-CSF. Here, IL6 is linked to COVID-19.