If you've had a positive COVID-19 test, you need to wait before getting any dose of the vaccine. You need to:
wait 4 weeks (28 days) if you're aged 18 years old or over
wait 12 weeks (84 days) if you're aged 12 to 17 years old
wait 4 weeks (28 days) if you're aged 12 to 17 years old and at high-risk from COVID-19
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Personally I'd go for the booster ASAP rather than putting it off until after, but then I only had an odd reaction for about 6h in total after my booster.
4 weeks is the minimum after infection (for adults, children have to wait 12 weeks unless they're high risk).
https://www.nhs.uk/conditions/coronavirus-covid-19/coronavirus-vaccination/book-coronavirus-vaccination/
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If you've had a positive COVID-19 test
If you've had a positive COVID-19 test, you need to wait before getting any dose of the vaccine. You need to:
wait 4 weeks (28 days) if you're aged 18 years old or over
wait 12 weeks (84 days) if you're aged 12 to 17 years old
wait 4 weeks (28 days) if you're aged 12 to 17 years old and at high-risk from COVID-19
"
Personally I'd go for the booster ASAP rather than putting it off until after, but then I only had an odd reaction for about 6h in total after my booster.