Watch: Head of European Medicines Agency says it is 'increasingly difficult' to say no link between Oxford jab and rare blood clots
The head of the European Medicines Agency (EMA) has said it is "increasingly difficult" to say there is "no cause and effect relationship" between the Oxford-AstraZeneca jab and "rare cases of unusual blood clots".
However, Marco Cavaleri, head of vaccine strategy at the EMA, told an Italian newspaper that full evaluation work was still "far from being completed" and that the risk-benefit ratio was still in favour of the vaccine.
He added: "We are a regulatory agency and we must have very precise data on the risk-benefit ratio.
"We are trying to get the precise picture of what is happening, to define in detail this syndrome due to the vaccine."
Of the 18.1 million people who have had the Oxford vaccine in the UK, 30 people have developed blood clots.
The UK's Medicines and Healthcare Products Regulatory Agency (MHRA) confirmed that of those 30 people, seven had died as of 24 March.
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The UK regulator has maintained there is no evidence to suggest a causal link between blood clots and the Oxford jab, and that the benefits continue to outweigh any risk.
But, when asked if the incidence of rare blood clots can be linked directly to the vaccine, Mr Cavaleri replied: "In my opinion we can now say it - it is clear there is an association with the vaccine.
"What causes this reaction, however, we still do not know".
"In summary: in the next few hours we will say the connection exists, but we still have to understand how this happens."
Mr Cavaleri confirmed the benefits of having the vaccination still outweighed the risks and added: "We will go into the various age groups in more detail. Young women, often protagonists of thrombosis cases, suffer less from the effect of COVID.
"We will therefore have to evaluate the risk-benefit ratio for them. Not forgetting that even young women end up in intensive care for COVID.
"Therefore, very meticulous work will be needed to understand if the risk-benefit ratio is in favour of the vaccine for all ages ".
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