In the described hepatitis B serology, which marker indicates current HBV infection?

In the described hepatitis B serology, which marker indicates current HBV infection?

• A. Anti-HBs
• B. HBsAg
• C. Anti-HBc
• D. HBeAg

Answer: (B)

HBsAg, the hepatitis B surface antigen, is the marker that shows current HBV infection. It appears early in infection and remains detectable in acute and chronic infection, indicating that the virus is present in the bloodstream and the person is infectious. In contrast, anti-HBs signals immunity (from vaccination or recovery), anti-HBc reflects exposure to the virus (IgM for recent infection, IgG for past exposure), and HBeAg indicates active viral replication and high infectivity but not the overall presence of infection itself. So, the presence of HBsAg is the best indicator that HBV infection is ongoing.

HBsAg, the hepatitis B surface antigen, is the marker that shows current HBV infection. It appears early in infection and remains detectable in acute and chronic infection, indicating that the virus is present in the bloodstream and the person is infectious. In contrast, anti-HBs signals immunity (from vaccination or recovery), anti-HBc reflects exposure to the virus (IgM for recent infection, IgG for past exposure), and HBeAg indicates active viral replication and high infectivity but not the overall presence of infection itself. So, the presence of HBsAg is the best indicator that HBV infection is ongoing.