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Medical regulators in the UK and Europe have announced their conclusions from their reviews of very rare cases of unusual blood clots in people who have received the Oxford-AstraZeneca coronavirus vaccine.

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Our vaccine work is progressing quickly. To ensure you have the latest information or to find out more about the trial, please visit the Oxford COVID-19 vaccine web hub or visit the COVID-19 trial website.

Both the UK's Medicines and Healthcare products Regulatory Agency (MHRA) and the EU's European Medicines Agency have concluded that whilst there was a possible link from these very rare blood clots to the vaccine, the benefits of vaccination continue to outweigh the risks in all age groups,  and have requested the product information is updated to mitigate further risks.

Both regulators have offered further advice to healthcare professionals, which can be found via the links below: 

Andrew Pollard, Professor of Paediatric Infection and Immunity, said: 

'Safety has been our priority throughout the development of the vaccine at Oxford University in 2020, and we are reassured to see that safety monitoring continues under the close scrutiny of regulators and public health authorities as the vaccine is rolled out around the world. 

'The identification of rare cases of blood clots, which might be associated with the vaccine, shows that the safety system works, and has also allowed MHRA and EMA to conclude that the benefits of vaccination continue to outweigh the risks, while putting in measures to help mitigate any possible risk. 

'The pandemic coronavirus continues to be a huge threat to people throughout the world, and we continue with our mission to support global vaccination, not for profit, for the benefit of humanity.'

In the UK, the Joint Committee on Vaccination and Immunisation has recommended that for adults aged under 30, if these persons are still unvaccinated, it is preferable for them to be offered an alternative COVID-19 vaccine, if available.   

They continue to add that: 

'To date, there are no reports of the extremely rare thrombosis/thrombocytopenia events following receipt of the second dose of the AstraZeneca COVID-19 vaccine. All those who have received a first dose of the AstraZeneca COVID-19 vaccine should continue to be offered a second dose of AstraZeneca COVID-19 vaccine, irrespective of age. The second dose will be important for longer lasting protection against COVID-19.'

The trial of the Oxford AstraZeneca COVID-19 vaccine in children continues with no safety concerns, though vaccinations were delayed this week while the researchers awaited the outcome of the MHRA review of very rare and unusual blood clots in adults. 

Following this recommendation of the JCVI, the researchers have decided that further vaccinations in the paediatric study will be postponed to allow further discussions with the MHRA and the trial’s Data Safety Monitoring Board, but all other visits will continue in this important study. 

Parents and young trial volunteers can contact their trial site for further information.

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