Write a short note on Hepatitis B Vaccine.

Definition

The hepatitis B vaccine is a recombinant (subunit) vaccine that protects against hepatitis B virus infection and its complications (chronic hepatitis, cirrhosis, hepatocellular carcinoma).

Schedule & Route

• Birth dose within 24 hours (crucial to prevent perinatal/vertical transmission), then as part of the pentavalent vaccine at 6, 10 and 14 weeks.
• Intramuscular (anterolateral thigh).

Key Points & Special Situations

• Infants of HBsAg-positive mothers should receive the birth dose (and, where available, hepatitis B immunoglobulin) promptly.
• A highly effective, safe vaccine; provides long-lasting protection.

Significance of the Birth Dose

A timely birth dose (within 24 hours) is the single most important measure to prevent perinatal (mother-to-child) transmission, which otherwise leads to a high rate of chronic carriage and later cirrhosis/liver cancer.

Key Points Recap

• Recombinant; birth dose < 24 h + pentavalent; prevents perinatal transmission.
• Freeze-sensitive — do not freeze; give HBIG to newborns of HBsAg+ mothers where available.

Programme Note

Universal hepatitis B vaccination (birth dose plus pentavalent) aims to reduce the pool of chronic carriers and, in the long term, the burden of cirrhosis and liver cancer.

Exam Relevance

This is a frequently asked short note — remember the vaccine type/route, its place in the UIP schedule, and its key precautions or programmatic significance.

The birth dose is the critical one for preventing vertical spread.