The scheme is set to start in September. It would seem some 23million over-50s, people classified as vulnerable and NHS workers and care staff offered a third Pfizer jab even if they had an alternative vaccine before.
Originally it was thought that those who were offered a third jab would be given the same vaccine they originally had - but now it is thought everyone will be offered Pfizer. This is because scientists have found this is the most effective against the Delta variant.
A source told the Times those who had the AstraZeneca vaccine would “be getting an “mRNA booster” - which means Pfizer or Moderna jabs.
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Pfizer and Moderna vaccines are mRNA jabs as it tells human cells to produce proteins from the virus which allows the body to create an immune response. This means those who had an mRNA jab have protection without being exposed to the virus.
Oxford AstraZeneca is not an mRNA jab.
The Government has said analysis shows the Pfizer vaccine is 96 per cent effective against the Delta variant.
Oxford/AstraZeneca vaccine is 92 per cent effective against hospitalisation after two doses, research shows.
Meanwhile another study, backed by the Government, published earlier this year found mixing vaccines may result in higher protection.
Research published earlier this week showed antibody levels among those given the Pzifer booster shot increased five-fold for those aged 18 to 55.
It has been reported the vaccines would be rolled out in two stages with those most at risk prioritised before it is rolled out to others.
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