BCG vaccine for TB

  • The Bacillus Calmette–Guérin (BCG) vaccine is used to prevent tuberculosis (TB). The BCG vaccine is named after Dr Albert Calmette and Dr Camille Guerin, who developed the vaccine from a germ called Mycobacterium bovis, which is similar to TB. BCG is a live vaccine that has been processed so that it is not harmful to humans.

    TB is an infectious disease caused by bacteria that affects the lungs, and sometimes other parts of the body. Because TB is not common in Australia, the BCG vaccine is not part of the routine vaccination schedule. However, the vaccine is recommended in some circumstances, such as travel to certain countries. For more information on TB, see our fact sheet Tuberculosis (TB).

    What does the BCG vaccine do?

    The BCG vaccine does not prevent someone being infected with the bacteria that causes TB, but it prevents the development of the disease. It is specifically designed to prevent TB in children. It is very effective in preventing severe TB in young infants, and can be given from birth onwards.

    How is it given?

    The BCG vaccine is given by an injection just under the skin, usually on the upper left arm.

    Sometimes, a test may need to be done before receiving the BCG vaccine. If there is a chance your child has already been infected with TB, the doctor will arrange for a TB skin test (Mantoux test). 

    If the skin test is positive (that is, your child may have previously been infected with TB) the BCG vaccine should not be given. If the skin test is negative, your child will be able to receive the BCG vaccine.  

    Who should get the BCG vaccine?

    Children, particularly those under five years of age, who are travelling to countries with a high rate of TB infections.

    Aboriginal and Torres Strait Islander babies in areas where there is a high incidence of TB.

    Babies whose parents and/or carers have TB.

    Who shouldn’t get the BCG vaccine?

    Some children should not get the BCG vaccine because the vaccine could cause complications. This includes those who:

    • have had TB before
    • have a positive Mantoux (skin) test
    • have HIV infection
    • have a condition or take medicines that weaken their immune system.

    What to expect after the BCG vaccination

    Reactions to vaccines (also called vaccine side effects) sometimes occur. The usual reaction to BCG vaccination is redness and/or a small lump at the injection site, followed by a small ulcer (an open sore) a few weeks later. The ulcer is usually less than a centimetre in diameter, and may last from a few weeks to a few months before healing to a small, flat scar.

    Care of the injection site 

    • Keep the area clean and dry.
    • It is OK to bathe your child as usual. Carefully pat the area dry after washing.
    • A wound dressing with gauze may be used if the area starts to ooze.
    • Use a sterile alcohol swab to clean the area if required.
    • Do not apply ointment, antiseptic creams, or sticking plasters (e.g. Band-Aids).

    When to see a doctor

    There are some rare side effects associated with the BCG vaccine. If any of the following occur, see your GP:

    • A large abscess (collection of pus) at the injection site.
    • Tenderness and swelling under the left arm – this could indicate an infection of the glands (called the axillary lymph nodes).
    • Very noticeable scarring of the skin at the injection site, known as keloid scarring.

    Key points to remember

    • The BCG vaccine prevents the development of TB, and is very effective in preventing severe TB in young infants. 
    • Your child may have an ulcer at the injection site for up to a few months.
    • Seek medical assistance if your child has a severe reaction at the injection site, or swelling/tenderness in their armpit.

    For more information  

    Common questions our doctors are asked

    I've heard there is a shortage of BCG vaccine – will I be able to get the vaccine for my child?

    In the past few years there has been a worldwide shortage of BCG vaccine. The Royal Children's Hospital has priority access and vaccines are available through the BCG clinic. Your GP can refer your child to the clinic, but be sure to get the referral well before your intended date of travel.

    Developed by The Royal Children's Hospital Emergency and Infectious Diseases departments and Immunisation Service. We acknowledge the input of RCH consumers and carers.

    Reviewed March 2018.

    This information is awaiting routine review. Please always seek the most recent advice from a registered and practising clinician.

    Kids Health Info is supported by The Royal Children’s Hospital Foundation. To donate, visit


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