Kids Health Info

BCG vaccine for TB Tuberculosis

  • BCG vaccine prevents tuberculosis (TB). BCG stands for "Bacille Calmette-Guerin" and is named after Dr Calmette and Dr Guerin who developed the vaccine in the early part of last century. It has been used since 1921 to prevent TB. BCG vaccine was developed from a germ similar to TB called Mycobacterium bovis. It is a live vaccine that has been processed so that it is not harmful to humans.

    What is TB?

    For more information please read the Kids Health Info factsheet:  TB tuberculosis

    What does the 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 such as meningitis (brain inflammation) in young infants and can be given from birth onwards.  BCG vaccine protects children for about 10 years and the World Health Organization recommends a single lifetime dose.

    How is it given?

    The BCG vaccine is given by an injection just under the skin (intradermal).  It is usually given on the upper left arm.

    In some instances, tests may need to be done before receiving the BCG vaccine.  This occurs if there is a chance your child has already been infected with TB.  If this is the case, the doctor will arrange for a TB skin test, called a Mantoux test.  If the skin test is positive (i.e. 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, travelling for extended periods to countries with a high incidence of TB.
    • Aboriginal babies in high TB risk areas.
    • Babies whose mothers have TB.

    Who should definitely NOT get the BCG vaccine?

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

    • Have had TB before.
    • Have a positive Mantoux (skin) test.
    • Have HIV infection.
    • Have an underlying condition or take medicines that weaken their immune system.
    • Are pregnant.

    Because TB is not common in Australia, BCG vaccine is not part of the routine vaccination schedule.

    What to expect following the BCG vaccination

    Adverse reactions to vaccines (also called vaccine side effects) do sometimes occcur.  The BCG vaccine is associated with some common and some rare side effects.

    Signs and symptoms

    The usual expected 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 one 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.
    • Normal bathing is acceptable.  Carefully pat the area dry after washing.
    • A temporary dry dressing with gauze may be used if the area starts to ooze.
    • A sterile alcohol swab may be used to clean the area if required.
    • Do not apply ointment, antiseptic creams, sticking plaster or band aids.

    Rare complications following BCG vaccine

    • A large abscess (collection of pus) at the injection site.
    • Infection of the glands in the left armpit (called the axillary lymph nodes) causing tenderness and swelling under the arm.
    • Very noticeable scarring of the skin at the injection site, known as keloid scarring.
    • Severe immediate allergic reation, however this is very rare.

    When to seek medical advice

    • If you notice a severe reaction at the injection site, such as a large, persistently discharging abscess.
    • If you notice swelling or tenderness of the glands (lymph nodes) in the left armpit.

    For more information 

    Produced by RCH Depts of Emergency and Infectious Diseases .First published Jan 2005. Updated August 2017.

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This information is intended to support, not replace, discussion with your doctor or healthcare professionals. The authors of these consumer health information handouts have made a considerable effort to ensure the information is accurate, up to date and easy to understand. The Royal Children's Hospital, Melbourne accepts no responsibility for any inaccuracies, information perceived as misleading, or the success of any treatment regimen detailed in these handouts. Information contained in the handouts is updated regularly and therefore you should always check you are referring to the most recent version of the handout. The onus is on you, the user, to ensure that you have downloaded the most up-to-date version of a consumer health information handout.