What does HBsAg stand for?

HBsAg stands for Hepatitis B Surface Antigen. This term refers to a protein on the surface of the Hepatitis B virus. The presence of HBsAg in the bloodstream is significant because it indicates that a person is currently infected with the virus and can potentially transmit it to others.

In clinical practice, the detection of HBsAg is crucial for diagnosing Hepatitis B virus infection and determining the infectious status of an individual. It is often the first marker to appear in acute Hepatitis B and is used in conjunction with other markers to assess the stage of the infection and the individual's immune response.

The other choices either misinterpret what HBsAg represents or introduce incorrect terminology. Understanding HBsAg is fundamental for healthcare professionals working in infectious diseases and public health, as it directly relates to patient management and treatment decisions regarding Hepatitis B.