Childhood vaccine
4-in-1 Preschool Booster
The 4-in-1 preschool booster tops up protection against diphtheria, tetanus, whooping cough and polio, given at around 3 years 4 months.
What it protects against
It boosts protection against diphtheria, tetanus, whooping cough (pertussis) and polio, following the earlier doses given in infancy.
Who it's for
Children at around 3 years and 4 months of age, before starting school.
How it works
It contains inactivated components of the germs, boosting the immune memory built up from the 6-in-1 doses so protection lasts through the school years.
Safety
Safety and side effects
It is safe and well tolerated. Common effects are soreness, redness or swelling at the injection site and being briefly unsettled, which soon settle.
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
4-in-1 Preschool Booster: frequently asked questions
Why does my child need another dose before school?
Protection from the baby doses fades over time, so this preschool booster tops it up to keep children protected against these serious diseases as they start mixing more at school.
Is the preschool booster the same as the baby vaccines?
It covers four of the same diseases (diphtheria, tetanus, whooping cough and polio) as a booster, but not hepatitis B or Hib, which were covered earlier. It reinforces the protection already built up.
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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