Hepatitis B DNA less than 100IU/ml may be hepatitis B virus DNA negative or hepatitis B virus DNA positive, and therefore it is also possible to be infected with hepatitis B. The lowest limit of hepatitis B DNA that can be detected using sensitive tests is 20 IU/ml. Hepatitis B DNA less than 100 IU/ml is negative if it is also less than 20 IU/ml, and hepatitis B infection can be basically ruled out if it is also negative for hepatitis B surface antigen. If Hepatitis B DNA is less than 100IU/ml but more than 20IU/ml, Hepatitis B DNA is positive, in which case Hepatitis B infection may exist and other Hepatitis B related tests need to be done to confirm the diagnosis. Hepatitis B DNA test is recommended to use sensitive methods to avoid false negatives and delay in diagnosis and treatment.