Specific cytokines such as interleukin (IL)-1α, IL-1β, IL-6, IL-10, IL-18, tumour necrosis factor (TNF)-α, monocyte chemoattractant protein-1 (MCP-1) and interferon (IFN)-γ-induced protein (IP-10) have indeed been positively associated with the severity of SARS-CoV-2 infection 4. This evidence concerns the gene CCL2 and severe acute respiratory syndrome.