Unusual blood clots should be listed as a possible side effect of the Astra Zeneca Covid 19 vaccine, according to Europe's health regulator.
The European Medicines Agency has found a possible link between the vaccine and rare blood clotting.
It insists the benefits of the jab outweigh the risks.
Executive Director of the EMA, Emer Cooke, says it is not possible to identify specific risk factors:
In the UK, people under 30 are going to be offered an alternative to the AstraZeneca vaccine where possible, because of the chance of developing rare blood clots.
The British medicines regulator says the link with the jab is getting firmer but, overall, the benefits continue to outweigh the risks for most people.
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