Transmission of HBV is by exposure to body fluids, most commonly blood. Highest amounts of the virus are present in blood.
Globally, the major source of HBV infection is perinatal transmission. In the UK, infection is most commonly acquired through injecting drug use or sexual intercourse.
Hepatitis B has a complex natural history and causes a range of disease. It has different clinical manifestations depending on the patient’s age at infection, their immune status and the stage at which the disease is diagnosed. Substantial health care resources are usually required to manage patients. In light of this, patients with mild disease may require monitoring rather than treatment, while treatment should be indicated for chronic progressive disease.
The goal of therapy is to prevent progression of the disease to cirrhosis and end stage liver disease.
Treatment may involve finite or long-term therapy, or a therapy course undefined at the beginning and dependent on the patient’s initial response.
Treatment should be given only when indicated. This should be carefully explained to patients to avoid perceptions of mismanagement when therapy is not forthcoming. Patients should be educated regarding liver function tests and preventing transmission of their infection.
Pre-exposure immunisation should be aimed at those at increased risk of hepatitis B because of lifestyle, occupation or other factors. Post-exposure vaccination is generally used to prevent infection in babies born to infected mothers, mothers infected during pregnancy, needlestick injuries, accidental inoculations or contaminations.
With the introduction of orally administered antiviral agents and newer pegylated interferons with sustained antiviral activity, a new era for the treatment of hepatitis B has begun. These therapies promise to improve the outcome of chronic HBV but will make further demands on still-evolving disease management and ascertainment, particularly when predicting the benefit of monotherapy against combination therapy.