Overview
BCG vaccine contains live attenuated Bacillus Calmette-Guérin (BCG) strain of Mycobacterium bovis. The vaccine will not prevent a person becoming infected with tuberculosis. However, when BCG vaccine is given just after birth, 7 out of 10 of infants and young children will be protected from developing severe forms of TB, e.g. meningeal TB (affecting the brain) and miliary TB (widespread).
Responses to vaccine
- Swollen glands and tiredness
- Small blister or ulcer at the injection site that may take up to 3 months to heal
- Scar at the injection site
- Bone inflammation
- Abscess
- Disseminated BCG disease, can be fatal when the BCG is given to a person with a weakened immune system
Other formulations and brands
Other brands: None
Schedule and administration
BCG vaccine is funded for infants and children less than five years of age who:
- Will be living with a person who currently has TB or has a past history of TB
- Have one or both parents or household members, who within the last five years, lived for a period of six months or longer in countries with a high TB rate (i.e. 40 or more TB cases per 100,000 people)
- During their first five years will be living for three months or longer in a country with a high TB rate and are likely to be exposed to those with TB
Catch-up doses
Infants and children at risk of TB can catch-up their missed BCG vaccine any time before their 5th birthday.
Storage and preparation
No special considerations are required for lyophilised vaccine, store as per cold chain between 2°C to 8°C and protect from light.
The diluent may be stored with the lyophilised vaccine or separately in a cool place. Once the vaccine has been reconstituted protect from light, store at 4°C and discard if not used within 4 hours.
Administration
The best time to administer the BCG vaccine is when the infant is between a few days old and six months of age.
Only BCG endorsed, authorised vaccinators may administer the BCG vaccine.
The vaccine is given as an intradermal injection over the left deltoid muscle. No further vaccinations should be administered into the left arm for at least three months.
BCG vaccine can be administered concurrently with other vaccines, including all National Immunisation Schedule vaccines. Separate syringes and different injection sites should be used.
Other live injected vaccine e.g. MMR or varicella vaccines, can be administered on the same day as BCG vaccine. When not injected on the same day as BCG vaccine, other live vaccines must be delayed until four weeks after the BCG. Inactivated/sub-unit vaccines can be given at any time interval before or after the BCG vaccine.
BCG vaccine can be administered at any time before or after rotavirus vaccine because the BCG vaccine is an injectable live vaccine and rotavirus is an oral live vaccine.
Re-vaccination with BCG vaccine is not recommended in New Zealand.
Vaccine Safety
BCG vaccine SSI should not be given to:
- Children who have a weakened immune system i.e.:
- Receiving corticosteroids or other immune suppressive treatment, including radiotherapy
- Suffering from some cancers
- In whom an immune compromising disease is known or suspected
- Known to be infected with HIV, including newborns with suspected HIV infection
- Those who have:
- A positive Mantoux reaction (5 mm or more)
- Generalised infected skin conditions. When eczema is present, an immunisation site should be chosen which is free of skin lesions
- Children over the age of five years and adults
- Anyone with severe allergy (anaphylaxis) to a previous dose of this vaccine, or a component of the vaccine
- Administration of BCG vaccine SSI should be postponed in individuals suffering from a fever over 38°C. The presence of a minor infection is not a reason to delay immunisation
Vaccine Effectiveness
BCG immunisation will not prevent tuberculosis infection. However, when the BCG immunisation has been given just after birth 70% of infants and young children will be protected from developing severe forms of TB i.e. meningeal TB (infection of the membranes covering the brain) and miliary TB.
The effectiveness of the BCG vaccine has been determined over time through observation that those who had received the BCG immunisation could still get pulmonary TB lesions but they were less likely to spread and cause serious forms of tuberculosis disease. The duration of immunity against TB after BCG is not known. However, studies suggest that it wanes with increasing age and could be non-existent 10-20 years after immunisation.
There is no blood test that can identify if a person is protected against TB after receiving a BCG.
A tuberculin skin test (TST or Mantoux test) indicates an immune response following a BCG immunisation but does not necessarily indicate a person has protection against the disease. The size of a TST response is not indicative of the degree of protection after a BCG. Studies have identified animals with a negative TST that were protected from TB and cases where administration of a TST boosted/increased a subsequent TST result but the animal was not protected from TB.
References
- ealthEd. BCG vaccine: Information for Health Professionals. Ministry of Health HE2204 Revised April 2019. Available from: https://www.healthed.govt.nz/resource/bcg-vaccine-information-health-professionals
- Health New Zealand | Te Whatu Ora, Immunisation handbook [Internet]. Available from: https://www.tewhatuora.govt.nz/for-health-professionals/clinical-guidance/immunisation-handbook