Hepatitis B is a bloodborne viral infection that can be prevented through vaccination. The hepatitis B virus (HBV) causes hepatitis (inflammation of the liver) and can also cause long term liver damage.
The average incubation period is 40-160 days. Many people have no symptoms while others experience a flu-like illness including a sore throat, tiredness, joint pains, and a loss of appetite. Other symptoms may include nausea and vomiting. Acute infection can be severe causing abdominal discomfort and jaundice. Mortality during the acute phase of infection is less than 1%.
The World Health Organization (WHO) estimates that in the UK the prevalence of chronic hepatitis B infection is 0.3%. Hepatitis B is more common in other parts of the world such as south east Asia, Africa, the middle and Far East and southern and eastern Europe. WHO estimates that there are 350 million chronically infected people world-wide.
The virus may be transmitted by contact with infected blood or body fluids such as through household or sexual contact with an infected person. The virus can be spread by the following routes:-
The failure to clear hepatitis B infection after six months leads to the chronic carrier state. Many people who become chronic carriers have no symptoms and are unaware that they are infected. These individuals will remain infectious and will be at risk of developing cirrhosis and primary liver cancer.
Alpha interferon is an antiviral drug that is used to treat patients with chronic hepatitis B infection. Other drugs with antiviral properties, such as lamivudine, are also used. Not all patients are suitable for treatment.
There is a vaccine available to prevent hepatitis B infection. The vaccine should be given to all individuals who are at risk from hepatitis B infection.
Consult Chapter 18 about Hepatitis B vaccination in the Green book: immunisation against infectious disease.
Last reviewed: 26 April 2013