Officials are close to finalising a deal to acquire tens of millions more doses of the vaccine in time for a third booster dose to be given to the elderly this autumn, the Sunday Times reports.
Government sources told the paper that they hope to roughly double the UK’s original order of 40 million jabs.
If negotiations are successful, the extra stock may also be used for those in their twenties.
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It comes as vaccine chiefs are said to be examining whether under-40s should not be given an alternative to the AstraZeneca jab amid blood clot fears.
New data from the Medical Healthcare products and Regulatory Agency (MHRA) suggested the risk of forming a serious blood clot has jumped from one in 250,000 to around one in 126,600 in a fortnight.
Earlier this month, new UK guidance was issued recommending that people aged 18 to 29 should be offered the Pfizer or Moderna vaccines, as the benefits of the AstraZeneca jab for younger people may not surpass the risks.
The Joint Committee on Vaccination and Immunisation (JCVI) is considering whether a further change of policy is needed for older groups, and is currently examining the new data ahead the rollout to under-40s
The chance of dying from a blood clot after having the AZ jab in the UK is about one in one million - after 19 died from around 20million vaccinations.
More than half the UK population, or 33.5 million people, have received their first Covid-19 vaccine, with 12 million having received their second dose.
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