IL17A and COVID-19: The ratio of neutrophils to lymphocytes was found to correlate with the severity of COVID-19,[94] which can produce excess cytokines such as tumor necrosis factor (TNF), IL-1, IL-6, IL-8, IL-12, and IL-17, creating a cytokine storm that can cause vasodilation, impair endothelial function, induce leukocyte recruitment and endothelial cell permeability, cause secondary inflammatory responses, and activate coagulation pathways,[95,96] ultimately leading to multiorgan dysfunction and aggravating the mortality of COVID-19.