As indicated by the AUC, ROC curve analysis indicated the potential of IL-22 (AUC = 0.95; 95% CI = 0.908–0.992; p < 0.001; cut-off point = 17.3 pg/mL; YI = 0.88; sensitivity = 95.9%; specificity = 92.2%) and IL-33 (AUC = 0.892; 95% CI = 0.839–0.945; p < 0.001; cut-off point = 30.7 pg/mL; YI = 0.8; sensitivity = 90.0%; specificity = 90.0%) in differentiating COVID-19 patients from HC (Fig. 3). Here, IL22 is linked to COVID-19.