Hepatitis B is a treatable liver disease caused by the hepatitis B virus (HBV), which can cause both acute and chronic infection of the liver. Acute hepatitis B infection lasts less than six months and most people who get hepatitis B as adults have an acute infection. However, if one’s immune system can’t fight the infection then the disease develops into a chronic hepatitis B infection, which may last a lifetime, possibly leading to serious illnesses such as cirrhosis and liver cancer.
The possibility that infection becomes chronic depends also on the age of the person infected. For example, children less than 6 years of age who become infected with the hepatitis B virus are the most likely to develop chronic infections. 80–90% of infants infected during the first year of life develop chronic infections; and 30–50% of children infected before the age of 6 years develop chronic infections, whereas in adults less than 5% of otherwise healthy persons who are infected as adults will develop chronic infection; and 20–30% of adults who are chronically infected will develop cirrhosis and/or liver cancer. 
A chronic HBV infection can lead to complications such as:
- Liver cirrhosis (scarring of the liver)
- Liver cancer or Hepatocellular carcinoma
- Liver failure
- Other conditions such as kidney disease or inflammation of blood vessels, are extrahepatic manifestations of the HBV
The symptoms appear about one to four months after the exposure to the virus but in most cases the patient remains asymptomatic. Symptoms may include:
- Abdominal pain
- dark urine
- joint pain
- loss of appetite
- nausea and vomiting
- weakness and fatigue
- yellowing of skin and the whites of eyes (jaundice).
The hepatitis B virus is transmitted through blood and body fluids. The virus can survive outside the body for at least 7 days. The incubation period of the hepatitis B virus is 75 days, but can vary from 30 to 180 days. Hepatitis B is most commonly spread from mother to child at birth or through exposure to infected blood, but the ways of transmission also include sexual contact and sharing of needles.
Most adults infected with acute hepatitis B recover fully within the 4 to 8 weeks. However, those who develop the chronic hepatitis B infection can be treated with medicines. Present treatments decrease the risk of developing cirrhosis or HCC and improve prognosis but the HBV cannot be totally cured due to long-lasting cccHBV-DNA, which persists inside the hepatocytes nucleus.
Hepatitis B infection can be prevented vaccinating newborns and infants. Most countries have anti HBV vaccine in the vaccines calendar for children.
Vaccine, which is known as the “anti-cancer” vaccine because it prevents hepatitis B, the leading cause of liver cancer worldwide, is also recommended for adults in high-risk groups.
If you are, or a person that you know is, suffering from the symptoms described above and are/is considered to belong to the populations at increased risk of HBV infection, contact your doctor or a liver patient organization in your country. European Liver Patients’ Association is an umbrella organization with the national patient organizations as members. List of our members can be found here.