Covid: Trigger of rare blood clots with AstraZeneca jab found by scientists

So Skybuck has only just found out about this. We've posted here about Astra-Zeneca blood clot risk before.

The critical point is that the blood clot reaction is rare - about ten per million people vaccinated - and not all that likely to kill - about one per million people vaccinated.

The BBC report gets around to this eventually - 73 deaths in 50 million people vaccinated (1.46 per million) - but doesn't mention that it has killed fewer people recently now that doctors know what to look out for and what to do if clotting does happen.

It's also a risk that is well worth running - it you do catch Covid-19 it is great deal more likely to kill you than the clotting problem.

What is interesting about this research is that they now understand the mechanism that causes the disastrous clumping that leads to blood clots. It turns out that the adenovirus carries a surprisingly strong negative surface charge capable of attracting certain blood proteins.

One of these proteins in some people is unfortunately a good fit and can bind on.

The AZ vaccine looks like it is very effective and over a broader range than the mRNA ones but the latter give higher initial antibody levels.

UK boosters will all be mRNA vaccines as the the trials have shown that for a booster dose they perform the best of all in everyone.