One British man has died and four more have suffered a dangerous blood clotting condition after being given the AstraZeneca vaccine, the Medicines and Healthcare Products Regulatory Agency (MHRA) confirmed on Thursday.
The five men, aged between 19 and 59, suffered from Cerebral Venous Sinus Thrombosis (CVST), although the MHRA said they did not know if it had been directly caused by the vaccine.
The MHRA urged people to continue getting the vaccine, adding that the chance of suffering the condition after a vaccination was currently just one in a million.
The condition is so rare that it is difficult to establish an underlying rate for the population.
Speaking at a press conference on Thursday afternoon, Dr Philip Bryan, MHRA Vaccines Safety Lead, said: “We have had five reports of a unique form of blood clot, Cerebral Venous Sinus Thrombosis, concurrent with low blood platelets. This is similar to some of the cases reported through Europe.
“What we don’t know is whether these have been caused by the vaccines. We are working closely to determine this, because these illnesses do very rarely happen naturally.
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“We do know that after more than five million this is extremely rare – less than one in a million cases of this even after vaccination.
“Covid disease is associated with significant mortality. Both vaccines are highly affected.
"And there is no proven causal association with what is still an extremely rare medical event.”
The MHRA said the benefit of vaccines “continues to be positive” but they are reviewing the individual cases to see if there is a link with the AstraZeneca jab.
The regulator said it was unclear if the men had underlying health conditions, although the lower age range suggests that they may have been classed as vulnerable to be allowed an early vaccine.
The experts said the cases were not linked to an individual batch.
On Thursday, the European Medicines Agency (EMA) is to rule on whether the AstraZeneca vaccine is responsible for several cases of blood clotting.
Several countries, including France, Germany, Italy and Sweden have paused their rollouts of the Oxford jab.
More to follow
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