Vaccine chiefs are said to be examining whether under-40s should be given another jab after 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 did not surpass the risks.
However, 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 Telegraph reports.
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.
On April 7, Jonathan Van-Tam, the deputy chief medical officer, shared data at a press conference that showed when Covid-19 is low in the community, the risk of developing a blood clot for the under-30s increases.
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At the time, the Government determined that the chance of serious harms from the jab for under 30s were around 1.1 in 100,000, while the risk of admission to intensive care was at 0.8 in 100,0000.
However, Prof Van-Tam said the advantage of the vaccine for 30 to 39-year-olds still exceeded the risks, with just 0.8 per 100,000 suffering serious harms from the vaccine compared to 2.7 in 100,000 who would be kept out of intensive care.
But, the doubling of incidence rate could change that.
Since the new figures emerged the MHRA chief executive Dr June Rain has reinforced the importance of people still coming forward for their jabs.
She said: “It is still vitally important that people come forward for their vaccination when invited to do so.”
The MHRA has also urged people who have received the jab to seek medical advice if they experience chronic headaches, particularly if followed by blurred vision, confusion, difficulty with speech, weakness, drowsiness or seizures.
People are also asked to look out for a rash that looks like a small bruise or bleeding under the skin, shortness of breath, chest pain, leg swelling and persistent stomach pain.
The JCVI and MHRA have been approached for comment.
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