Hepatitis B

 

NEET PG High-Yield: Hepatitis B

Hepatitis B Virus (HBV) is a major cause of chronic liver disease, cirrhosis, and hepatocellular carcinoma (HCC).

Feature Description
Causative Agent HBV (Hepadnaviridae family, DNA virus).
Transmission Parenteral (blood), Sexual, Perinatal (vertical).
Incubation Period Long: 30–180 days (average 60–90 days).

Serology Markers (High-Yield)

  • HBsAg: First marker to appear; indicates active infection.
  • Anti-HBs: Indicates immunity (post-vaccination or recovery).
  • HBeAg: Marker of high infectivity/viral replication.
  • Anti-HBc IgM: Marker of acute infection (“window period” hallmark).
High-Yield NEET PG Pearls:

  • Vaccine: Recombinant DNA vaccine (HBsAg).
  • Post-Exposure: Administer HBV vaccine + Hepatitis B Immunoglobulin (HBIG) to exposed non-immune individuals.
  • Vertical Transmission: Prevention is key—screen all pregnant women; give HBIG + vaccine to the newborn within 24 hours of birth.
  • Chronic Infection: Defined as HBsAg positive for > 6 months.