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What is The following is a marker of acute hepatitis B infection: and explain in detail?
HBV-DNA can be measured by PCR in the blood. Viral loads are usually in excess of 105 copies/mL in the presence of active viral replication, as indicated by the presence of e antigen. In contrast, in individuals with low viral replication, who are HBsAg- and anti-HBe-positive, viral loads are less than 105 copies/mL.
Reference: : Davidson P R I N C I P L E S   and Practice O F M E D I C I N E 23rd edition page no  875