What Is Hepatitis B?

Hepatitis B is a common viral infection that causes damage to the liver. Although there is currently no cure, treatments are available. It can range from a mild illness to a serious, lifelong condition.

More than 2 billion people around the world have been infected with hepatitis B. It’s estimated that nearly 1 in 3 people will be infected with hepatitis B during their lives. In developing countries, mothers can transmit the infection to their babies.

In the United States, most cases of hepatitis B originate with unprotected sex with someone who is infected. Pregnant women are usually tested for hepatitis B, and babies are now routinely vaccinated with the hepatitis B vaccine.

The greatest risk of getting hepatitis B belongs to people who:

  • Have unprotected sex with many partners
  • Work with human blood, body fluids or needles
  • Work or live in a prison or long-term care facility
  • Live with someone who is infected
  • Had blood transfusions or organ transplants before the early 1990s
  • Take medications to suppress the immune system
  • Have HIV (human immunodeficiency virus) or hepatitis C infections 
  • Are from Asian and Pacific Island nations
  • Have a blood-clotting disorder
  • Use dialysis for kidney failure
  • Use IV (intravenous) drugs

Hepatitis B has two forms:

  • Acute hepatitis B: This is the name for a new infection that can last up to six months. Sometimes the immune system can fight the infection and it goes away.
  • Chronic hepatitis B: This is the name for a long-term infection that doesn’t go away. Without treatment, people with hepatitis B may develop chronic liver disease or liver failure.