CD4 and lymphopenia: The respiratory distress peaks at 7 to 10 days with manifestations of immune dysregulation, including cytokine release syndrome with elevation of cytokine levels (IL‐6, IL‐8, IL‐1, IL2R, IL‐10, and TNF‐α), lymphopenia (in CD4+ and CD8+ T cells), and decreases in IFN‐γ expression in CD4+ T cells.8, 9