Contrarily, patients with COVID-19 who were severely infected experienced an excessive release of cytokines and chemokines, such as interleukin (IL)-1, IL-2, IL-6, IL-7, IL-8, IL-10, granulocyte-colony stimulating factor (GCSF), and tumour necrosis factor-alpha (TNF-α) [34,35,36,37]. Here, IL7 is linked to COVID-19.