In hepatitis B infection, which serological marker indicates ongoing viral replication and high infectivity?

• A HBsAg alone
• B HBeAg ✓
• C Anti-HBs
• D Anti-HBe

Explanation

HBeAg (hepatitis B e antigen) is a secreted protein derived from the precore/core region of HBV and serves as a marker of active viral replication and high infectivity (correlates with HBV DNA >10⁵–10⁷ copies/mL). Its presence indicates a highly infectious state. Anti-HBe seroconversion (loss of HBeAg, appearance of anti-HBe) correlates with reduction in viral replication and infectivity. Anti-HBs indicates immunity (vaccination or past resolved infection). HBsAg indicates current infection but does not discriminate replicative from non-replicative states as precisely as HBeAg.

Reference: Ananthanarayan & Paniker's Textbook of Microbiology, 11th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.