Hepatitis is a general term for inflammation of the liver. Hepatitis can be caused by several things including immune system disorders, alcohol exposure, toxins, or by viruses known as hepatitis A, B, C, D and E. Infection with the hepatitis B virus (HBV) causes the condition known as hepatitis B. This condition can be contracted by contact with the body fluids of a person infected with HBV. For people infected as adults, a hepatitis B infection clears up by itself, but for others, including most of the individuals infected at birth, hepatitis B can cause chronic infection leading to cirrhosis (scarring) of the liver, liver cancer, and death.

Due to routine vaccination against HBV, hepatitis B infections are relatively uncommon in the developed world with an estimated 60,000 cases occurring each year in the United States. Unfortunately, HBV vaccination is less common in the developing world and The World Health Organization estimates that worldwide, 2 billion people have been infected with HBV and more than 350 million are living with chronic hepatitis B. Around 250,000 people die each year worldwide from liver damaged caused by chronic hepatitis B infection.