Childhood vaccine
BCG Vaccine
The BCG vaccine protects against tuberculosis (TB). In the UK it is offered to babies and others at higher risk, rather than to everyone.
What it protects against
It protects against tuberculosis (TB), a bacterial infection that mainly affects the lungs but can affect other parts of the body, and is particularly good at preventing severe TB in young children.
Who it's for
Babies and children at higher risk of TB — for example those with family from countries where TB is more common, or living in areas with higher rates — rather than the whole population.
How it works
It is a live but weakened form of a related bacterium, which prompts the immune system to build protection against TB.
Safety
Safety and side effects
It is given as an injection into the skin, usually the upper arm, and typically leaves a small sore that heals into a tiny scar. Serious side effects are rare. It is not given to people with a severely weakened immune system.
Education and reference only. This is general information, not a personal recommendation, and does not list doses — follow the current NHS schedule and your clinician's advice. Seek urgent help for signs of a serious allergic reaction after any vaccine.
Answers
BCG Vaccine: frequently asked questions
Why isn’t the BCG given to everyone in the UK?
TB is now relatively uncommon in the UK, so the vaccine is targeted at babies and others at higher risk, where it does the most good, rather than being given routinely to the whole population.
Why does the BCG leave a scar?
The BCG is injected into the skin and usually causes a small blister or sore that heals over several weeks, leaving a small scar. This is a normal and expected part of the vaccine.
Related
Other childhood vaccines
Sources
Where this is drawn from
- NHS — Vaccinations
- UK Health Security Agency (UKHSA) — the Green Book
- WHO — immunization
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