Hepatitis B
Worldwide over 400 million people are infected with hepatitis B.
The majority of infections in the UK are acquired early in life particularly individuals born in the developing world. Some countries have a prevalence of over 10%.
Acute hepatitis B is less common than chronic (long standing) disease, but can be fatal. There is an effective vaccine which can prevent transmission of hepatitis B
The term 'carrier' is no longer correct; as many people assumed to have insignificant hepatitis B go on to develop cirrhosis and liver cancer.
Hepatitis B can undergo periods of being inactive and then reactivate after many years, even in people assumed to be healthy 'carriers'. Lifelong follow up and monitoring is required for this condition as effective treatments exist.
Investigations
Anyone infected with hepatitis B should undergo routine liver tests at least once a year, and often more frequently.
New tests have been developed which accurately measure the level of the virus in the blood - the viral load. Monitoring the viral load over time is vital to predicting the course of the infection.
Ultrasound examination helps to determine the degree of damage to the liver and to assess for development of liver cancer. Hepatitis B is by far the commonest cause of hepatitis worldwide, and certain infected individuals need regular surveillance for liver cancer, as this can be cured if picked up in its early stages.
Liver biopsy helps to confirm the diagnosis and assess the degree of scarring (fibrosis) in the liver.
Non-invasive tests of liver fibrosis such as 'fibroscan' and blood test markers of fibrosis will be used with increasing frequency in the future.
Treatment
Treatment of hepatitis B has radically changed over the past 5 years with several new drugs becoming available.
Treatment consists of either pegylated interferon or oral antivirals such as lamivudine, adefovir, telbivudine or entecavir.