EB-DNA quantitative blood cell is a quantitative blood cell test for EBV (human herpesvirus) DNA. EBV is a ubiquitous human herpes virus, and studies have shown a strong correlation between EBV and the development of nasopharyngeal carcinoma.The genetic material of EBV is DNA, and quantitative DNA testing can reflect the amount of EBV in the organism. If the quantitative blood cell test result of EBV DNA is lower than the lower limit of the test, it means that the subject’s body does not contain EBV or contains a very small amount of EBV, which indicates that his/her chance of suffering from nasopharyngeal carcinoma is low. However, even if the EBV level in the body is high, it does not necessarily lead to the development of the disease. As long as we strengthen the prevention, avoid smoking and other risk factors, generally will not develop the disease, and regular review can be done. Meanwhile, EBV can also cause infectious mononucleosis, childhood lymphoma, hemophagocytic syndrome and other diseases, patients should pay attention.