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Hepatitis B

Key facts

  • Your baby is most at risk of catching hepatitis B infection at birth.

  • Catching hepatitis B at birth leads to chronic infection in about 90 per cent of babies. One in four chronically infected babies die of liver failure or liver cancer as an adult.

  • The hepatitis B vaccine is a safe vaccine for newborns.

Last updated on 27 April 2023.

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What is hepatitis B?

Hepatitis B is a serious infectious disease caused by the hepatitis B virus (HBV). It mainly affects the liver.1 It passes from person to person through blood and body fluids, and can be passed from a mother to a child at birth or soon after.

Some people infected with the hepatitis B virus experience mild flu-like symptoms; some experience more severe symptoms including fever, nausea and vomiting, pain in the liver, pain in the joints and yellowing of the skin (called ‘jaundice’).

Most adults who are infected with the hepatitis B virus recover fully. However, around 10 per cent develop chronic hepatitis B which can lead to liver disease and liver cancer.2

The risk of developing chronic hepatitis B is greatest in babies.1 Around 90 per cent of babies who catch hepatitis B at birth will develop chronic hepatitis B.2

Hepatitis B is highly contagious. You can be infected if you come into contact with blood or other body fluids from someone who carries the virus, even if that person shows no signs of illness. The greatest risk of infection occurs at birth when a mother who carries the virus can pass it on to her baby.1

Infection can also occur:

  • during breastfeeding, if the mother carries the virus
  • when adults or children come into contact with the open sores or cuts of an infected adult or child
  • when adults or children share certain personal items with an infected person, such as a toothbrush
  • when adults or children eat or share food that has been chewed or sucked by an infected person
  • when adults or children are bitten by an infected person
  • as a result of sharing needles or a needle stick injury
  • when someone has unprotected sex with an infected person.

The virus can survive on objects for up to seven days, so infection can occur a number of days after an adult or child has been in contact with someone who carries the virus.

The hepatitis B virus is highly infectious and is 50 to 100 times more infectious than HIV, the human immunodeficiency virus that causes AIDS.3

In 2013 there were around 210,000 people living with chronic hepatitis B, and around 389 deaths related to chronic hepatitis B.4 Overall, hepatitis B is not as common in Australia as it is in some other countries, however it is more common within some groups including Aboriginal and Torres Strait Islander communities.

What will happen if my baby catches hepatitis B?

Babies under one year usually don’t look or feel sick when they first catch hepatitis B, but it can cause serious liver diseases, including liver cancer, later in life. 

The risks associated with hepatitis B are much greater for babies than they are for adults. Around 90 per cent of babies who catch hepatitis B at birth develop chronic hepatitis B. (Less than 10 per cent of adults who get the infection develop chronic hepatitis B.2)

  • There is no cure for chronic hepatitis B infection.
  • People with chronic hepatitis B need long-term antiviral therapy to reduce the risk of developing liver cancer.5

Around one in four babies who catch hepatitis B at birth or soon after will die of liver failure or liver cancer as an adult.6

How can I protect my baby from hepatitis B?

The highest risk period for babies is at birth1, and babies should have their first dose of the hepatitis B vaccine within 24 hours of being born.

Many people who are carrying hepatitis B don’t know they have the virus. It is possible for a mother to have hepatitis B while she is pregnant and pass it on to her baby during the birth without knowing it. Even mothers who have had blood tests showing no sign of hepatitis B virus can be carrying hepatitis B and pass it on to their babies during the birth.7

About half of the children who catch hepatitis B get it during their births. People who catch hepatitis B while they are young babies almost always develop serious liver damage (cirrhosis) or cancer as adults.

When should my baby be vaccinated?

It is recommended that babies have their first dose of the hepatitis B vaccine within 24 hours of being born. Further doses are recommended at six weeks, four months and six months of age.1

Where do I go to get my baby vaccinated?

If your baby is born in a hospital, the midwife or trained immunisation nurse in the postnatal ward will give your baby a hepatitis B vaccination. 

How does the hepatitis B vaccine work?

The vaccine works by training your baby’s immune system to recognise and get rid of the hepatitis B virus. The vaccine contains ‘antigens’ which are tiny fragments of the hepatitis B virus. When your baby’s immune system detects the antigens in the vaccine, it produces antibodies to fight them and get rid of them.

Hepatitis B is a viral infection and the antigen in the hepatitis B vaccine is a tiny, synthetically made fragment of the virus. The vaccine does not contain any blood products and is not a ‘live’ vaccine. The synthetic fragments cannot reproduce themselves or cause disease.

Is it safe to give the vaccine to a newborn baby?

Yes, the hepatitis B vaccine is safe for newborns.

  • There is no evidence that the dose given at birth affects a mother and baby’s ability to breastfeed.8,9
  • There is no evidence that the birth dose is associated with Sudden Unexpected Death in Infancy (SUDI) or Sudden Infant Death Syndrome (SIDS).10
  • There is no evidence that the birth dose is associated with autism.11
  • The birth dose is not associated with an increased risk of fever.8,9
  • The birth dose is not associated with an increased need for medical investigations into serious infection or sepsis in newborns.8,9

Premature babies are even more vulnerable to infection than full-term babies. For that reason, it is just as important to give the hepatitis B vaccine to premature babies to protect them from this serious infection. Your doctor or nurse can advise you on the best time for your baby to have their first dose of the vaccine, and whether an additional dose is required

Most babies get two needles (injections) at birth. One is the hepatitis B vaccine and the other is a vitamin K injection.

Vitamin K is not a vaccine. Babies usually get a vitamin K injection in their leg shortly after birth. Vitamin K helps prevent a condition called Vitamin K Deficiency Bleeding by helping the baby’s blood to clot. Vitamin K can also be given as drops in the mouth (oral vitamin K drops) over several days. Most health professionals recommend the vitamin K injection because it only needs to be given once.12

How effective is the vaccine?

Between 90 and 95 per cent of people under 40 who have had three doses of the hepatitis B vaccine, as recommended in the National Immunisation Program, are protected against the hepatitis B virus.13

Some lifestyle factors - including age, obesity, certain infectious diseases or a history of smoking - can impact on the effectiveness of the hepatitis B vaccine. Speak with your doctor if you have questions about how lifestyle factors could impact on the effectiveness of the vaccination for your baby, or anyone else in your family.

Will my baby have a reaction to the vaccine?

Newborn babies don’t usually have any noticeable reaction to the hepatitis B vaccine after the sting of the needles has passed. New babies who get these injections don’t usually get the reactions (like fever or allergic reactions to something in the vaccines) that older babies can get.8

If you are worried about your baby, you can get help from:

  • your doctor
  • your nearest emergency department
  • or by calling Health Direct on 1800 022 222.
Are there any rare and/or serious effects to the hepatitis B vaccine?

Researchers haven’t found any serious side effects from the birth dose of the hepatitis B vaccine. Serious side effects can happen when older babies and children get vaccines that include hepatitis B, but they are very rare.

If you are worried about your baby, you can get help from:

  • your doctor
  • your nearest emergency department
  • or by calling Health Direct on 1800 022 222.

The development of this content was led by the Murdoch Children's Research Institute for the MumBubVax website (now archived).

  1. NCIRS. Hepatitis B vaccines for Australians. Westmead, NSW: National Centre for Immunisation Research and Surveillance; 2020. Available:
  2. Edmunds WJ, Medley GF, Nokes DJ, Hall AJ, Whittle HC. The influence of age on the development of the hepatitis B carrier state. Proc Biol Sci. 1993;253:197-201.
  3. WHO. Hepatitis B: How can I protect myself? World Health Organization; 2015 [updated July 2015; cited 6 September 2018]. Available from:
  4. MacLachlan JH, Allard N, Towell V, Cowie BC. The burden of chronic hepatitis B virus infection in Australia, 2011. Australian and New Zealand Journal of Public Health. 2013;37:416-22.
  5. Papatheodoridis GV, Lampertico P, Manolakopoulos S, Lok A. Incidence of hepatocellular carcinoma in chronic hepatitis B patients receiving nucleos(t)ide therapy: a systematic review. Journal of Hepatology. 2010;53:348-56.
  6. Shepard CW, Simard EP, Finelli L, Fiore AE, Bell BP. Hepatitis B virus infection: epidemiology and vaccination. Epidemiologic Reviews. 2006;28:112-25.
  7. Australian Technical Advisory Group on Immunisation (ATAGI). Australian Immunisation Handbook, Australian Government Department of Health, Canberra, 2018,
  8. Lewis E, Shinefield HR, Woodruff BA, Black SB, Destefano F, Chen RT, et al. Safety of neonatal hepatitis B vaccine administration. Pediatric Infectious Disease Journal. 2001;20:1049- 54.
  9. Eriksen EM, Perlman JA, Miller A, Marcy SM, Lee H, Vadheim C, et al. Lack of association between hepatitis B birth immunization and neonatal death: a population-based study from the Vaccine Safety Datalink Project. Pediatric Infectious Disease Journal. 2004;23:656-61.
  10. Institute of Medicine (US) Immunization Safety Review Committee. Immunization Safety Review: Vaccinations and Sudden Unexpected Death in Infancy. Washington, DC: National Academies Press, 2003.
  11. Taylor LE, Swerdfeger AL, Eslick GD. Vaccines are not associated with autism: An evidence-based meta-analysis of case-control and cohort studies. Vaccine. 2014;32(29):3623-9.
  12. Joint statement and recommendations on vitamin K administration to newborn infants to prevent vitamin K deficiency bleeding in infancy. Commonwealth of Australia. 2010. Accessed 21NOV2018
  13. Van Damme P, Ward J, Shouval D, Wiersma S, Zanetti A. Hepatitis B vaccines. In: Plotkin SA, Orenstein WA, Offit PA (editors). Vaccines. 6th edition. Philadelphia, PA: Elsevier Saunders; 2013. p. 205-34.