The COVID booster jabs rollout has been extended to all adults aged over 40 from today, it has been announced.
It comes after a recommendation by the Joint Committee on Vaccination and Immunisation (JCVI) and results from the first real-world study by the UK Health Security Agency.
The study shows that two weeks after receiving a booster dose, protection against symptomatic infection for adults aged 50 and over was 93.1% in those who had an AstraZeneca dose, and 94% for Pfizer.
The JCVI, the independent expert advisory committee that advises ministers on immunisation, has also announced that it will be advising that all 16 and 17 year olds have a second dose of the Pfizer vaccine.
Previously, only those in this age group considered to be in an "at-risk" group were eligible.
Second doses for 16 and 17 year olds should be given at least 12 weeks after initial jabs, the JCVI suggests.
The body had previously advised booster vaccinations for all adults aged 50 years and over and those at greater risk from COVID-19.
More on Covid-19
COVID-19: 'In our hands' whether or not coronavirus restrictions will return over winter, says Tory party co-chair
COVID-19: Online hate speech has increased by 20% in the UK since start of the pandemic, research finds
COVID-19: Austria imposes lockdown on unvaccinated citizens – as Europe becomes epicentre of pandemic
They add that, following two doses of the vaccine, as yet, there is no "robust evidence of a decline in protection against severe COVID-19 (hospitalisations and deaths) in those aged under 40 years".
The JCVI says that they will continue to closely review all available data to develop further advice in due course.