Most adults who are infected with the hepatitis B virus completely recover from the infection and develop immunity to the virus. But some people (usually infants and young children) are unable to clear the virus from their bodies, and develop a chronic, or long-term, infection.
Of the 350 to 400 million people worldwide who are chronically infected with hepatitis B, many live in the Asia-Pacific region. An estimated 209,000 people in Australia have chronic hepatitis B infection.
Infants and children infected with hepatitis B rarely experience any symptoms of acute infection, but are at high risk of developing chronic hepatitis B infection. Many people with chronic hepatitis B can go up to 20 to 30 years without experiencing any symptoms.
Most of the people in Australia with chronic hepatitis B infection were born overseas, in countries with high rates of hepatitis B infection. In Aboriginal and Torres Strait Islander communities, there are also higher rates of chronic hepatitis B infection.
The hepatitis B virus is spread through:
- sharing of drug injecting equipment;
- unprotected sexual contact;
- close family contact with someone with hepatitis B;
- reuse of unsterilised or inadequately sterilised needles;
- needlestick injuries among healthcare workers; and
- from an infected mother to her baby at birth.
Complications of chronic hepatitis B
Chronic hepatitis B infection can result in complications such as cirrhosis (scarring of the liver) and liver cancer. The amount of hepatitis B virus in the blood — known as the viral load — helps determine the likelihood of developing these complications. Higher viral loads are associated with an increased risk of developing cirrhosis and cancer of the liver, so keeping the viral load as low as possible can help reduce or prevent injury to the liver.
Habitual alcohol use, smoking and co-infection with HIV or Hepatitis C also increase the likelihood of developing liver damage.
The aim of treatment for chronic hepatitis B is stop the hepatitis B virus from replicating in your cells, reduce the amount of hepatitis B virus in the blood, and stop the progression of liver disease and prevent liver cancer.
There are 2 types of medicines that are used in the treatment of chronic hepatitis B. These include:
- medicines that work on the immune system, such as pegylated interferon; and
- direct antivirals, such as entecavir, tenofovir, lamivudine, adefovir and telbivudine.
There are many people currently living with chronic hepatitis B who are not being treated and face an increased risk of complications and death from their disease. If you have chronic hepatitis B infection, see your doctor, who can advise you on whether one of these treatments may be suitable for you.
Also, it’s important to remember that hepatitis B is a contagious disease. If you have chronic hepatitis B, you should make sure that anyone you are in close contact with is vaccinated against the disease. The hepatitis B vaccine is part of the routine childhood immunisation schedule.