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• PCR looks directly for the virus's unique DNA, instead of the method employed by the
standard test, which looks for indirect evidence that the virus is present by searching for
antibodies the body has made against it.
Screening for viral hepatitis: Diagnostics (HBV and HCV)
Serology markers of HBV infection:

Figure 17: HBV antigen

HBV antigens:

Surface Ag
e Ag
Core Ag

Marker Normal interpretation
Surface Antigen Viraemia
e Antigen High infectivity
Core IgM Recent acute infection
Surface antibody Immunity
Core IgG Exposure to HBV

Quantifying HBV: HBV DNA level or HBsAg?
cccDNA (covalently closed circular) DNA best marker of viral burden
Serum HBV DNA level