CD4 and lymphopenia: In its severe form, corona virus disease-19 (COVID-19) is characterized by various immunological abnormalities, dominated by massive pro-inflammatory cytokine and chemokine release, such as IL-6, TNF-α, IL-1b, IFN-y and monocyte chemoattractant protein-1 (MCP-1), associated with T CD3, T CD4 and T CD8 lymphopenia.