COVID SPRING BOOSTERS
Booster doses are an important part of protecting yourself from COVID-19 if you are at higher risk from severe COVID-19.
Like some other vaccines, levels of protection may decline over time. Booster doses help boost your antibodies and give you good protection from becoming seriously ill or needing to go to hospital if you catch COVID-19.
https://www.nhs.uk/conditions/covid-19/covid-19-vaccination/getting-a-booster-dose-of-the-covid-19-vaccine/: COVID SPRING BOOSTERS