EPO and hepatitis A virus infection: The following data were collected for most of the subjects: blood routine (33 cases), ferritin (29 cases), Anti streptolysin O (ASO) (33 cases), Epstein-Barr virus (EB virus) (17 cases), hepatitis B (22 cases), erythropoietin (EPO) levels (16 cases), etc. FTL levels detected by ELISA were negatively correlated with RBC and Platelets (PLT) and positively correlated with ferritin, CRP, and HBeAg.