PIK3C2A and COVID-19: We investigated the relationship between sex, age, BMI, SBP, DBP, and smoking status as demographical factors, biochemical features including BUN, serum zinc, copper, Cr, triglyceride, cholesterol, FBG, hs-CRP, phosphorus, LDL-C, HDL-C, Gamma-GT, CPK, direct bilirubin, calcium, total bilirubin, AST, ALT, ALP, uric acid, and magnesium, and hematologic features including WBC, RBC, hemoglobin, hematocrit, MCV, MCH, MCHC, RDW, PDW, and MPV with COVID-19 through DT, BF, and LR algorithms, to obtain the related parameters and the best predicting factors.