HBsAg

HBsAg (Hepatitis B surface antigen) is a protein that is produced by the hepatitis B virus. The presence of HBsAg in the blood typically indicates a current hepatitis B infection, either acute or chronic.

HBsAg Test Positive Device

Overview

HBsAg is the first marker that appears in the blood following infection with hepatitis B virus. It is a part of the outer surface of the virus, and it can be detected in high levels in the blood during acute or chronic hepatitis B virus infection. The body normally produces antibodies against HBsAg as part of the normal immune response to infection.

Clinical significance

HBsAg is used together with other hepatitis B virus markers to determine the disease state of an individual. The presence of HBsAg can be used to diagnose acute or chronic hepatitis B virus infection. It can also be used to screen for the virus in blood donations and in clinical settings.

Testing

Testing for HBsAg is done using a blood test. The test can be done as part of a series of tests to diagnose hepatitis B virus infection. The test can also be used to monitor the effectiveness of treatment for hepatitis B virus infection.

See also

• Hepatitis B virus
• Hepatitis B
• Hepatitis
• Virus
• Infection