What is hepatitis B?
Hepatitis B is a serious viral disease that affects the liver. ‘Hepatitis’ means inflammation of the liver. Hepatitis B infection can be either acute (short-lived) or chronic (long-term). Chronic hepatitis B can result in complications such as cirrhosis (liver scarring), liver failure and liver cancer.
Because infants and children who are infected with hepatitis B virus have a high risk of developing chronic hepatitis B infection, childhood immunisation against hepatitis B is recommended and is included in the National Immunisation Program Schedule in Australia.
How is hepatitis B spread?
Hepatitis B is found in the bodily fluids (such as blood, saliva and semen) of people with acute and chronic hepatitis B. Hepatitis B can be transmitted in a number of different ways, including through:
- sexual contact;
- mother-to-newborn infection during the birthing process;
- sharing contaminated drug injecting equipment;
- using non-sterile, contaminated instruments such as those used for body-piercing and tattooing; and, to a lesser extent,
- sharing personal items that could break the skin (such as toothbrushes or razors) and household contact (for example contact between children with open sores).
Symptoms of acute hepatitis B infection usually develop about 3 months after being infected with the virus. Symptoms may include:
- jaundice (a yellowish discoloration of the eyes and skin);
- pale faeces and dark urine;
- reduced appetite;
- nausea and vomiting;
- abdominal pain or discomfort (especially in the upper right region of the abdomen);
- skin rash; and
- joint and muscle pain.
Most infants and young children experience no symptoms, and only about 30 to 50 per cent of adults experience symptoms. People who have not experienced any symptoms may not be aware that they have been infected, and unwittingly pass the infection on to others.
Hepatitis B tests and diagnosis
Your doctor will take a history, asking about any symptoms and risk factors for hepatitis B that you may have, and perform a physical examination.
Blood tests are available that can help determine whether you have acute or chronic hepatitis B infection, or have had a past infection with hepatitis B. These blood tests measure:
- hepatitis B surface antigen (part of the outer surface of the virus); and
- antibodies against the hepatitis B virus (produced by your immune system).
Liver function tests are blood tests that can help assess the how well your liver is working and the extent of inflammation and liver damage.
Most adults who are infected with hepatitis B virus recover completely, clearing the virus from their bodies within 6 months without any specific treatment. If you are experiencing symptoms of acute hepatitis, your doctor may suggest treatments to help you feel more comfortable while your immune system is fighting the infection. Follow-up blood tests can determine whether there is any evidence of ongoing infection.
Treatments available for chronic hepatitis B infection include antiviral medicines and medicines that work on the immune system.
If you know that you have recently been exposed to hepatitis B, a treatment called hepatitis B immune globulin can help prevent acute hepatitis B infection developing, if given within 24 hours of exposure.
Hepatitis B vaccination
The most effective way of preventing the spread of hepatitis B is through vaccination. All children are eligible for free vaccination in Australia.
The National Immunisation Program Schedule recommends that the first hepatitis B vaccination is given at birth. Three further doses are then administered at 2, 4, and 6 months of age. These are given in combination with other routine immunisations, so that no additional jabs are required. Immunity from hepatitis B vaccination is long lasting.
Catch-up vaccination at 10 to 13 years of age is recommended for children who have missed being vaccinated. Vaccination is also recommended for adults who are at increased risk of hepatitis B infection and those at increased risk of severe disease.
Those at increased risk include:
- people who may be exposed to the virus as a result of their occupation (such as healthcare workers and emergency services personnel);
- residents and staff of facilities for people with developmental disabilities;
- inmates and staff of correctional facilities;
- injecting drug users;
- people undergoing haemodialysis, people with HIV and other adults with impaired immunity;
- people with clotting disorders that require them to receive blood product concentrates;
- people with hepatitis C or other chronic liver disease;
- transplant recipients;
- people who have prolonged household contact with a carrier of the disease;
- people at risk of contracting the disease through sex with an infected person;
- migrants from countries where there are high rates of hepatitis B infection (including East and Southeast Asia, sub-Saharan Africa and the Pacific Islands);
- Aboriginal and Torres Strait Islander people; and
- travellers to countries where there are high rates of hepatitis B infection.
If you are unsure about whether you have been vaccinated or previously exposed to hepatitis B, ask your doctor about having a blood test to check for antibodies to the hepatitis virus.
Possible side effects of hepatitis B vaccination are soreness around the injection area, fever, joint pain or a feeling of being unwell. However, the risks of not immunising your child are much greater, as hepatitis B is a serious disease with potentially life-threatening consequences.
The birth dose of hepatitis B vaccine is very well tolerated and is not associated with an increased risk of fever. Severe allergic reactions in adults have been very rarely reported.
2. Australian Government Department of Health. National Immunisation Program Schedule (from July 2013). http://www.immunise.health.gov.au/internet/immunise/publishing.nsf/Content/nips-ctn (accessed Jul 2014).
3. Immunise Australia Program. Hepatitis B (updated 10 Feb 2014). http://www.immunise.health.gov.au/internet/immunise/publishing.nsf/Content/immunise-hepb (accessed Jul 2014).
4. Gastroenterological Society of Australia (GESA); Digestive Health Foundation (DHF). Hepatitis B â€“ a vaccine preventable disease (Fifth Edition, 2012). http://www.gesa.org.au/consumer.asp?id=83 (accessed Jul 2014).
5. MayoClinic.com. Hepatitis B (updated 1 Sep 2011). http://www.mayoclinic.org/diseases-conditions/hepatitis-b/basics/definition/con-20022210 (accessed Jul 2014).