Hepatitis B is a virus which causes liver inflammation.
Most people who become infected with hepatitis B get rid of the virus within six months. A short infection is known as an acute case of hepatitis B.
Approximately 10 percent of people infected with the hepatitis B virus develop a chronic, life-long infection. People with chronic infection may have symptoms, but many of these patients never develop symptoms. These patients, sometimes referred to as carriers, can spread the disease to others. Having chronic hepatitis B increases one's chance of permanent liver damage, including cirrhosis (scarring of the liver) and liver cancer.
Hepatitis B is transmitted via blood and other body fluids. A person can acquire Hepatitis B through:
- Contact with blood in healthcare settings
- Unsafe sex with an infected person
- Blood transfusions
- Sharing needles
- Receiving a tattoo or acupuncture with contaminated instruments
- Birth (an infected mother can transmit the virus to the baby during delivery or shortly thereafter)
The risk of becoming chronically infected depends on the person's age at the time of infection. More than 90 percent of newborns, about 50 percent of children, and less than five percent of adults infected with hepatitis B develop chronic hepatitis.