- The European Medicines agency has said that the AstraZeneca vaccine should list blood clots as a "rare" side effect.
- This comes as Oxford University halted administering the vaccine to kids.
- There are now concerns that Europe's vaccine rollouts will be hampered.
The European Medicines Agency said Wednesday that blood clots should be listed as a "very rare" side effect of the AstraZeneca coronavirus vaccine but that the jab's benefits continue to outweigh the risks.
"EMA's safety committee has concluded today that unusual blood clots with low blood platelets should be listed as very rare side effects" of the shot, the Amsterdam-based EU drug regulator said in a statement.
"One plausible explanation for the combination of blood clots and low blood platelets is an immune response, leading to a condition similar to one seen sometimes in patients treated with heparin," the EMA said.
The findings come as a major hurdle in the global fight against the pandemic and a shift in the stance of the regulator, which had last week backed the vaccine and said there was no increased risk of blood clots in general from the shot.
It is also a blow to AstraZeneca, which was a frontrunner in the race for making an effective vaccine against Covid-19 ever since it began working with the University of Oxford.
The EMA's safety committee, which was assessing the vaccine, has requested for more studies and changes to the current ones to get more information.
Meanwhile, European Union health ministers have been told the EU drug regulator's decision on the safety of the AstraZeneca vaccine is expected to have an immediate impact on vaccination plans and to require a coordinated response, a letter seen by Reuters showed.
The letter was sent by the Portuguese presidency of the EU on Tuesday to invite health ministers for an extraordinary virtual meeting on Wednesday to be held immediately after the decision by the EU drugs regulator on the AstraZeneca vaccine.
The regulator said on Wednesday that the vaccine had possible links with very rare cases of unusual blood clots with low blood platelet counts, but it reiterated that the vaccine's advantages outweighed its risks.
"We expect this announcement will have a direct and immediate impact not only on our national vaccination plans, but also in our citizens' trust in vaccines against Covid-19," the letter says.
"Harmonization at an EU level will be essential to stop the spread of misinformation," it adds.
- Additional reporting by Reuters