Quick Answer

The hepatitis B vaccine prevents infection with the hepatitis B virus (HBV), which attacks the liver and can cause chronic disease, cirrhosis, or liver cancer. It is recommended for all infants, children, and adults at risk, including healthcare workers and people with multiple sexual partners. The vaccine does not treat existing hepatitis B or protect against hepatitis A or C.

  • Hepatitis B spreads through blood, semen, and other body fluids.
  • The vaccine contains a harmless piece of the virus to trigger immunity.
  • It is given as a series of 2, 3, or 4 shots over 6 months.
  • Chronic hepatitis B can lead to liver scarring or cancer.
  • The vaccine is over 90% effective after the full series.
  • Hepatitis A and C require separate vaccines or treatments.

Context Most Pages Skip

Hepatitis B is a viral infection that inflames the liver, caused by the hepatitis B virus (HBV). Unlike hepatitis A, which spreads through contaminated food or water, HBV passes via blood or sexual contact, similar to hepatitis C. The vaccine works by training your immune system to recognize and fight the virus before it can cause harm. It is a key tool in preventing long-term liver damage, but it does not treat an active infection or protect against other hepatitis types.

Related Questions

⚕️ This page is educational and does not replace advice from a licensed clinician. If you may have been exposed to an STI, get tested — most infections are manageable, and many are fully curable.

Sources & Further Reading

Figures reflect CDC surveillance and WHO estimates; they are population statistics, not personal risk predictions.