If it is advised that your baby has the Bacillus Calmette-Guérin (BCG) vaccine, it is usually offered after birth while your baby is still in hospital.
The BCG vaccine can also be given to older children and adults (see below).
It is given as an injection into the upper arm.
Mantoux (tuberculin) test
A tuberculin skin test, or Mantoux test, should be carried out before the BCG vaccination is given for:
- all individuals aged six years or over
- infants and children under six years of age with a history of residence or prolonged stay (more than three months) in a country with an annual TB incidence of 40 per 100,000 or greater
- those who have had close contact with a person with known TB
- those who have a family history of TB within the last five years
The Mantoux test checks whether you have a TB infection or disease. This is necessary as many people can become infected with the bacteria that cause TB but do not develop any symptoms (known as latent TB).
The test involves injecting your skin with a substance called purified protein derivative (PPD) tuberculin. If you have immunity to TB, your skin will be sensitive to PPD tuberculin and a hard red bump will develop at the site of the injection, usually within 48 to 72 hours of having the test.
If you develop this reaction (a positive test result), you should not be vaccinated, as the BCG vaccine has no clinical benefit and may cause unpleasant side effects.
If the test proves negative, the BCG vaccine is given.
Who should have the BCG vaccination?
There is little evidence that the BCG vaccine is effective in older people. TB vaccinations are not usually offered to people over the age of 16 unless the risk of exposure is great (for example, if they have come from Sub-Saharan Africa).
Babies
BCG vaccination is recommended for all babies who:
- are born in areas where the rates of TB are high
- have one or more parents or grandparents who were born in countries with a high incidence of TB
Older children and adults
- Older children who were not vaccinated against TB when they were babies, and who have an increased risk of getting TB, should be vaccinated.
- Anyone under 16 who has come from an area where TB is widespread should consider the BCG vaccination.
- Anyone under 16 who has been in close contact with someone who has pulmonary TB (TB infection of the lung) should consider the BCG vaccination.
At-risk occupations
A BCG vaccination is recommended if you are under 35 and work in an occupation with an increased risk of exposure to TB. These people include:
- laboratory staff who are in contact with clinical materials, such as blood, urine and tissue samples
- veterinary staff and other animal workers, such as abattoir workers, who work with animals that are susceptible to TB, such as cattle or monkeys
- prison staff who work directly with prisoners
- staff of care homes for the elderly
- staff of hostels for homeless people
- staff who work in facilities for refugees and asylum seekers
- healthcare workers with an increased risk of exposure to TB
Who should not have the BCG vaccination?
The BCG vaccine is not recommended for:
- people who have already had a BCG vaccination
- people with a past history of TB
- people with a positive skin test
- people who have had a previous anaphylactic reaction (severe allergic reaction) to any of the substances used in the vaccine
- newborn babies in a household where a case of TB is suspected or confirmed
- people who have a septic skin condition
- people who have received another live vaccine less than three weeks earlier
- people with a weakened immune system, either as a result of a health condition (such as HIV) or treatments such as chemotherapy or immunosuppressant medication (medication that suppresses the immune system)
- people who have cancer of the white blood cells, bone marrow or lymph nodes, such as leukaemia or lymphoma
- people who are seriously unwell (vaccination should be delayed until they recover)
Pregnant women and over-16s
TB vaccinations are not usually offered to people aged over 16. Some people over 16 and under 35 whose work puts them at occupational risk should be offered the vaccine (see above). There is limited evidence that the vaccine is effective in those over 16 and virtually no evidence that shows it is effective in those aged over 35.
As a safety precaution, the BCG vaccine is usually not recommended during pregnancy, unless it is thought that the benefits outweigh any possible risks. There have been no recorded reports of the BCG vaccine affecting pregnancy.