BCG vaccine (TB)

Protection for babies and children who are at high risk of coming into contact with tuberculosis (TB)

Single live BCG vaccine

Single live BCG vaccine

Protects against

Tuberculosis (TB)

Primary course

1 dose

Boosters

None

Suitable for ages

From 28 days upwards (with proof of the SCID test for babies in the pilot scheme)

What is the BCG vaccine?

The BCG vaccine is designed to protect against tuberculosis, a bacterial infection that can affect the lungs and other parts of the body including the kidneys, spine and brain.

While some people can fight off tuberculosis naturally, others experience serious health complications or even die after catching this illness. The vaccine has been shown to significantly reduce the risks of developing serious health conditions.

How does the BCG vaccine work?

The BCG vaccine is made from a weakened strain of TB bacteria. Because the bacteria in the vaccine is weak, it teaches the immune system how to protect against the infection but does not give your child TB.

Who should have the BCG vaccine?

The BCG vaccine is only recommended in the UK for people who have a high chance of coming into contact with someone who has TB.

This includes babies (up to one year old) who:

  • Are born/live in areas of the UK where TB rates are high (i.e. 40 or more cases per year per 100,000 population)
  • Have a parent or grandparent who was born in a country where there’s a high rate of TB
  • Live with, or are a close contact of, someone with infectious TB

If you have a child between the ages of one and 16, the recommendations above also apply. The vaccine may also be advised if your child:

  • Has recently arrived from a country with high levels of TB (including those in Africa, the Indian subcontinent, parts of southeast Asia, parts of South and Central America, and parts of the Middle East)
  • Will be living with local people for three months or longer in countries with high rates of TB

If you’re unsure about whether your child needs the BCG vaccine, the best thing to do is to book an immunisation consultation at BabyJabs to discuss their case.

SCID screening

In September 2021, Public Health England released new rules for the BCG vaccination, increasing the minimum age for vaccination to 28 days. This is to support a pilot programme to test eligible newborns for Severe Combined Immunodeficiency (SCID).

Currently, every newborn is given a heel prick blood test that screens for nine rare diseases, including sickle cell and cystic fibrosis. The NHS is considering introducing another test for SCID because approximately 14 babies a year are born in England with this life-threatening condition and early detection is vital.

Treating a child with SCID can be more complicated if they have had the BCG vaccine. If your child is in the pilot scheme and has been tested for SCID then it is crucial that we wait for a negative result before going ahead with the vaccination.

If your child is in the pilot scheme, we will need written confirmation from the SCID programme of a negative result. If your child was born outside of the programme areas and, therefore, not included in the scheme, we will need a letter from your GP or health visitor confirming this.

Note: No letter is required for children born before 1st September 2021.

BCG vaccine FAQs

BCG stands for Bacillus Calmette-Guérin and is named after its inventors, Albert Calmette and Camille Guérin.

People sometimes question the efficacy of the BCG vaccine because approximately 1.5 million people still die from TB every year (including 214,000 people with HIV).

Eight countries account for two-thirds of this total, with India leading the count, followed by China, Indonesia, the Philippines, Pakistan, Nigeria, Bangladesh and South Africa.

Although some studies have measured the BCG vaccine as having no protective effect at all, an in-depth review of 1,264 articles and abstracts about research into the vaccination concluded that it significantly reduces the risk of TB by 50%, with protection being observed across many populations, study designs and forms of TB.

Here in the UK, the BCG vaccine is around 78% effective when given to teenage school children and around 64% effective in British Asian babies.

There is still uncertainty about how effective the vaccine is in UK babies from other ethnic groups but research does show that it prevents the more serious types of TB, such as TB meningitis.

According to the World Health Organisation, an estimated 66 million lives were saved through TB diagnosis and treatment between 2000 and 2020. Globally, TB incidence fell by 11% between 2015 and 2020; the BCG vaccine was an important factor.

Like all vaccines, the BCG vaccine can cause side effects. For the majority of people, they’re mild.

The most common side effect (affecting 9 out of 10 people) is:

  • Hardness at the injection site, followed by a raised blister – this typically leaves a small scar once it has healed

Uncommon side effects (affecting up to 1 in 100 people at each dose) may include:

  • A high temperature (fever)
  • Headache
  • An ulcer that develops from the blister at the injection site two to six weeks after injection – this may be painful and take several weeks or months to heal fully (If you have any concerns, please contact us for advice)
  • Swollen glands in the neck or under the armpit in the arm where the injection was given (this can affect up to 1 in 50 people but is usually around 1 in 300)
  • An enlarged lymph node that becomes infected (lymphadenitis)

Rare side effects (affecting up to 1 in 1000 people at each dose) include:

  • More severe skin reactions that usually heal within a few weeks
  • Bone inflammation (osteitis or osteomyelitis)
  • An abscess at the injection site

The most serious side effect of the BCG vaccine is to get a widespread TB-like infection. This very rare – though occasionally fatal – complication occurs in around one in 200,000 doses. It is mainly confined to babies with impaired immune systems but, of course, an impaired immune system can be difficult to detect in a newborn. This is one of the reasons why SCID screening is being introduced as it will highlight newborns who are immunocompromised.

A severe allergic reaction (anaphylaxis) is very rare, occurring in one in 900,000 people per dose.

As a live vaccine, the BCG jab should not be given to anyone with an impaired immune system, including those suspected of being HIV positive.

This includes children under the age of six months who may have been exposed to an immunosuppressive treatment either in utero (during pregnancy) or while being breastfed.

If your child has already had TB, they should not receive the vaccine as they would have an increased risk of experiencing adverse reactions.

The BCG vaccine is usually given in the left upper arm.

It must be injected only just beneath the surface of the skin (intradermally) so that a small lump appears on the skin as the injection is being given. This is the recommended site so that the small scar left after vaccination can be easily found in the future as evidence of previous vaccination.

The lump will increase in size over the next few weeks, during which it will scale and crust over; a small ulcer sometimes occurs, which may ooze and require a protective dressing. The lesion then slowly heals over several months, resulting in a characteristic flat circular scar.

No further immunisation should be given in the same arm for at least three months.

The manufacturer’s leaflet states “strictly to be given in the arm”. If there is a reason that the vaccine can’t be done in the arm, we will need to be notified before the appointment and parents will be asked to sign a disclaimer that the vaccine is being given at a site that is against the manufacturer’s advice.

Young people, aged 16 to 35, are sometimes advised to have the BCG vaccination if they are:

  • Healthcare or laboratory workers who have either direct contact with patients with TB or with potentially infectious clinical samples and materials
  • Veterinary staff or other animal workers who may handle animals or animal materials that could be infected with TB

The vaccine is also sometimes offered to:

  • Prison staff who work directly with prisoners
  • Staff working at hostels for homeless people
  • Staff who work in facilities for refugees and asylum seekers

There is limited evidence about how well the vaccine works in young people over the age of 16 and adults.

The BCG vaccination should only be given once. A recent study suggests that the protective effect lasts for around 20 years, after which it gradually decreases.

The BCG vaccine can be given any time after 28 days – or once a newborn has received the result of the SCID heel prick test – and is best given under the age of one. However, children under the age of 16 who are in one or more of the high-risk categories that we’ve mentioned above can also have this vaccine.

The BCG vaccine is given as a single dose and would not usually need to be repeated.

If your child has had the vaccine in the past but you want to check their level of immunity – or they want to check their immunity later in life – this can be investigated with the appropriate skin test.

The BCG vaccination can be given at the same time as other live vaccines such as those for measles and rubella. 

Measles/Measles and Rubella/MMR vaccination and tuberculin skin testing (see question below) can be performed on the same day. However, if a tuberculin skin test has already been initiated, then Measles/Measles and Rubella/MMR should be delayed until the skin test has been read unless protection against measles is required urgently. If your child has had a recent Measles/Measles and Rubella/MMR vaccination, and requires a tuberculin test, then a four-week interval should be observed.

The Mantoux skin test – sometimes called the tuberculin skin test (TST) – is necessary before BCG immunisation for:

  • All adults and children over six years of age
  • Babies and children under six years of age who have lived or stayed for more than three months in a country with a high incidence of TB
  • Anyone who has had close contact with someone with TB
  • Anyone with TB in the family within the last five years

The Mantoux test involves injecting a tiny quantity of extracts of the TB bacterium (bug) into the forearm. The skin is examined two to three days later.

If there is a skin reaction (usually a small, hard lump at the injection site), it means the person having the test could have latent or active TB and should not have the vaccine until further investigations have been done.

The Mantoux skin test can show us whether someone has already been vaccinated against TB too.

The BCG vaccine was offered to all 10 to 14-year-olds between 1953 and 2005 but is no longer a part of the NHS childhood vaccination schedule.

There are now such low rates of TB in the general population of the UK that the decision was made in 2005 to switch to a targeted programme for babies, children and young adults at higher risk of TB.

TB is difficult to catch because it requires fairly prolonged close contact with an infected person.

BCG vaccine ingredients

Name: BCG Vaccine AJV

Age: From 28 days upwards (with proof of the SCID test for babies in the pilot scheme)

Manufacturer: Statens Serum Institut (Denmark)

Active ingredients: Live attenuated bacteria of the type Mycobacterium bovis BCG (Bacillus Calmette-Guerin), Danish strain 1331 – 1 ml vaccine contains between 2-8 million bacteria

Other ingredients: Sodium glutamate, magnesium sulphate heptahydrate, dipotassium phosphate, L-asparagine monohydrate, ferric ammonium citrate, glycerol 85%, citric acid monohydrate and water for injections

BCG Vaccine AJV contains less than 1 mmol potassium (39 mg) per dose, i.e. essentially ‘potassium-free’
BCG Vaccine AJV contains less than 1 mmol sodium (23 mg) per dose, i.e. essentially ‘sodium-free’

Mercury content: Nil

Aluminium content: Nil

Contains porcine gelatin?: No

Contains dairy products?: No

Licensed for use in the UK

BCG Vaccine AJV patient information leaflet: Click to view

Aftercare

We’ll give you detailed aftercare advice for your child after their vaccination(s), including what to do in the event of any side effects.

As we’ve mentioned already, it is common for the BCG vaccine to cause a small blister at the injection site that leaves a slight scar.

You can download our Patient Aftercare leaflet here.

If your child is unwell outside of clinic hours, please call 111 for advice or go to A&E if they need urgent medical attention.

Individual advice about the BCG vaccination

Need advice about whether your child should have the BCG vaccine? The BabyJabs team is here to listen and answer your questions to help you decide.