TABLE 2.

Interpretations of available serologic test results for HBV

HBsAg	IgM anti-HBc	Total anti-HBc	Anti-HBs	Interpretation
+	−	−	−	Early HBV infection before anti-HBc response.
+	+	+	−	Early HBV infection. Because IgM anti-HBc is positive, the onset is within 6 months. IgG antibody usually appears shortly after IgM; therefore, both are usually posi-tive when IgM is positive.
−	+	+	− or +	Recent acute HBV infection (within 4–6 months) with resolution; i.e., HBsAg has already disappeared. Anti-HBs usually appears within a few weeks or months of HBsAg disappearance.
+	−	+	−	HBV infection, onset at least 6 months earlier because IgM anti-HBc has disappeared. Prob-able chronic HBV infection.
−	−	−	+	Response to hepatitis B vaccine. No evidence of infection.
−	−	+	+	Past HBV infection, recovered.