The increased secretion of the pro-inflammatory cytokines and chemokines IL-6, Interferon-gamma (IFN-γ), Monocyte Chemoattractant Protein-1 (MCP-1), and IFN-γ-induced Protein 10 (IP-10) attracts immune cells, notably monocytes and T lymphocytes, but not neutrophils, from the blood into the infected site, explaining the lymphopenia and the increased neutrophil-lymphocyte ratio seen in around 80% of patients with SARS-CoV-2 infection (27). This evidence concerns the gene CCL2 and lymphopenia.