Like all medicines, vaccines can cause side effects. Most of these are mild and short-term, and not everyone gets them. Very common side effects in the first day or two include:
These are normal signs that the body is building immunity.
A mild fever may occur shortly after vaccination and last for a day or two. However, a high temperature could also indicate that they have Covid or another infection.
There has been a very small number of reports for myocarditis and pericarditis (inflammation of the heart) in individuals under 18, both in the UK and internationally. Most of these young people recovered quickly and felt better following rest and simple treatments.
You should seek medical advice urgently if your child experiences:
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