Hepatitis B Surface Antigen
Hepatitis B surface antigen (HBsAg) is a protein on the surface of the hepatitis B virus; its presence in blood indicates active hepatitis B infection.
Why it matters: Detection of HBsAg is the primary marker for diagnosing acute or chronic hepatitis B infection and for screening blood donors.
What is Hepatitis B Surface Antigen?
Hepatitis B surface antigen (HBsAg) is a protein on the surface of the hepatitis B virus; its presence in blood indicates active hepatitis B infection.
What might a high or low Hepatitis B Surface Antigen mean?
Detection of HBsAg is the primary marker for diagnosing acute or chronic hepatitis B infection and for screening blood donors.
Track your Hepatitis B Surface Antigen over time
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