• Hepatitis B is the most common liver virus in the world.
  • There is a safe and effective vaccine to protect you against hepatitis B.
  • You can get treatment to manage chronic hepatitis B but not cure it.

Hepatitis B, sometimes called hep B or HBV, is a virus that causes damage to your liver. It can be chronic, which means you could have it your whole life. There is a safe and effective vaccine to protect you against hep B.

How do you get hepatitis B?

You can get hepatitis B if infected blood or body fluids get into your blood, or if you have unprotected sex. You cannot get hepatitis B through saliva.

The most common time people get hepatitis B is early in life. Infants can get hep B during childbirth in a vaginal or caesarean delivery. If you are pregnant and have hepatitis B, your baby should get an injection within 12 hours of being born. This injection contains the first dose of vaccine, as well as hepatitis B immunoglobulin, which are antibodies that help the immune system to fight the virus. This injection, together with the rest of the vaccine course, is very effective at protecting the baby against hepatitis B.2

Some women can also benefit from treatment during pregnancy to reduce the risk of passing the virus on to their baby.

Some other ways you can get hep B include:

  • having vaginal, anal or oral sex without a condom
  • tattooing or body piercing with unsterile equipment
  • medical procedures with unsterile equipment
  • sharing needles, syringes or other injecting equipment, including spoons
  • sharing toothbrushes, razors or nail files
  • having uncovered cuts or sores.1

You cannot get hepatitis B through:

  • hugging or kissing
  • sharing food and eating utensils
  • eating food made by someone with hepatitis B
  • insect or animal bites, including mosquitoes
  • sharing bathrooms, showers or toilets
  • sneezing or coughing.1

What happens if you get hep B?

If you get hepatitis B, your body’s immune system will try and fight the virus. Then, there are two things that could happen. You could get an acute illness or a chronic illness.

  1. Acute hepatitis B means the virus might make you sick for a short time but then you will recover. Some people with acute hepatitis B naturally clear the virus. If the virus stays in your liver for more than six months, then you will have chronic hepatitis B.

  2. Chronic hepatitis B means the virus stays in your liver for your whole life. You may not always feel sick, but over time the virus can hurt your liver so it does not work properly.3

How hepatitis B affects each person is very complex, but in general, younger children more likely to get chronic hepatitis B if they are exposed to the virus.

This table shows what is likely to happen, depending on how old you are when you get hepatitis B:4

Age (when exposed)

Acute hepatitis B

Chronic hepatitis B

Infants (under 1 years old)

Most will not get any acute hep B symptoms

90% will get chronic hep B if not given prophylaxis (birth dose) injection and vaccines

Children (aged 1 to 6 years old)

Most will not get any acute hep B symptoms

30% will get chronic hep B

Adults or older children (over 6 years old)

Many will get acute hep B symptoms

Less than 5% will get chronic hep B

Finding out if you have hepatitis B is simple. Your doctor can do blood tests to see if you have ever had the hepatitis B virus and whether you currently have the virus in your blood. If you do have the virus, then the doctor may do other tests to check if your liver has been damaged.

If you have chronic hepatitis B, it is very important that you see your doctor regularly to monitor it. If chronic hepatitis B is not managed appropriately, it can cause cirrhosis (also known as scarring of the liver), liver failure and liver cancer. The good news is there are treatments available to help reduce damage to your liver.

If you don’t have hepatitis B, you can get a vaccine to protect you against it in the future.

Download this factsheet


More information about hepatitis B

Use the following links to learn more about hepatitis B:

Testing for Hepatitis B

Monitoring hepatitis B

Hepatitis B Vaccination

Symptoms of Hepatitis B

Hepatitis B Treatment

References:

  1. ASHM. (2019). Hepatitis B. Retrieved from All good: allgood.org.au/english/hbv/
  2. ASHM. (2018). Managing hepatitis B virus in pregnancy and children. Retrieved from ASHM: www.hepatitisb.org.au/managing-hepatitis-b-virus-in-pregnancy-and-children/
  3. ASHM. (2014). B Positive: All you wanted to know about hepatitis B. Darlinghurst, NSW: ASHM. Retrieved from ASHM: www.ashm.org.au/products/product/1976963310
  4. WHO. (2018, July 18). Hepatitis B. Retrieved from World Health Organisation: www.who.int/news-room/fact-sheets/detail/hepatitis-b

Page Updated: 13 August 2019