Later, they can develop severe liver diseases, or cancer. Hepatitis B spreads through contact with blood or other body fluids. This can happen through sexual contact, by sharing a razor, toothbrush, needles used to inject drugs, or to tattoo. It usually causes a rash, itching, tiredness and fever. It can lead to pneumonia, brain infection or death.
Complications occur most often in very young children, adults or people with damaged immune systems.
For a more in-depth description of these diseases, check out the Center for Disease Control's Home Page .