Hepatitis B is a fairly common inflammation of the liver in all countries of the world, brought about by infection with Hepatitis B virus (HBV), which is the second leading cause of acute hepatitis after HAV virus, responsible for hepatitis A.
On initial infection, hepatitis B presents in an acute form, characterized by varying severity and duration depending on the age and characteristics of the patient and his or her response to the virus.
Most adults affected by hepatitis B recover completely, while 5-10% develop a chronic form (the risk of chronicity is highest in children, reaching 25-50% between 1 and 5 years and 90% in infants). Of the patients affected by chronic hepatitis B, about 1 in 5 will go on to experience cirrhosis of the liver within 5 years and will be at an increased risk of developing liver cancer.