- HBsAG: Surface antigen
- Positive in:
- Acute infection (first marker to rise)
- Chronic infection (> 6 months)
- HBsAB (IgG): Surface antibody
- It represents victory; victory can be achieved in two ways:
- Resolved acute infection
3. HBcAB: Core antibody
- IgM appears during “acute” phase and persists during “window” phase (the only marker +ve during “window” phae)
- IgM converts entirely to IgG after 6 months. So IgG is +ve in:
A. Resolved acute infection
B. Chronic infection
NOTE: HBsAG is protective but HBcAB is not.
- It results from breakdown of core antigen from infected liver cells and is, therefore, marker of infectivity (i.e,. patient can transmit infection to others).
Mnemonic: ”e” for envelope – Envelope is used for sending letters to others