Furthermore, COVID-19 caused excessive production of proinflammatory cytokines such as IL-6, IL-2, IL-7, granulocyte-colony stimulating factor (G-CSF), Macrophage Inflammatory Protein-1 Alpha ((MIP-1-α)/CCL3, and TNF-α), termed as cytokine storm (Chen et al., 2021). Here, IL7 is linked to COVID-19.