IL6 and COVID-19: Our results indicated that serum IL-6 levels were not elevated in nonsevere COVID-19 cases compared to healthy controls (P = 0.13) (Figure 5(a)), while IL-6 levels were elevated in severe patients compared to healthy controls (WMD = 25.05, 95% CI: 6.92-43.17, and P < 0.01) (Figure 5(b)).