A clear link between Covid's AstraZeneca shot and rare blood clot to the brain reported by official

Originally published at: A clear link between Covid's AstraZeneca shot and rare blood clot to the brain reported by official | Boing Boing


I retract this post. Clearly the link is turning out the be stronger than it seemed when this was posted.

Cavaleri provided no evidence to support his comment.

This whole thing appears evidence-free at this point.

The fact that the incidence of blood clots seems on par or less than the incidence of blood clots in the general population should make us skeptical of such claims. Arbitrarily subdividing the data in order to try to make a correlation, without any known mechanism (why “women under 55?”), smacks of p-hacking.

It’s the same as those jelly beans: xkcd: Significant

Except in this case they haven’t even made that case, they’re just muttering that there may be some link without evidence.

I feel like spreading this is spreading FUD about vaccines.


It’s worse than that, it’s the European Medicines Agency making a song and dance about the Oxford-AstraZenica vaccine because the EU have been in a spat with AstraZenica about AZ sticking to their contracts about how much vaccine they deliver to who and when rather than favouring the EU over vaccine deliveries.

I think those responsible at the EMA should be made to write a 1000 times "I have been a naughty boy playing politics with science and I must remember that correlation does not imply causality (especially when I’ve been dividing the numbers up to get the result I wanted to get).".

Re-reporting it uncritically is tantamount to collusion.


100%. This story should be removed.


Could be a factor, but it’s also true that the EMA isn’t alone in expressing these concerns about a potential link. Per an AP story:

So I guess we’ll see the WHO assessment soon. Interesting that they would use the word “conclusive,” as it’s hard to imagine there’s a whole lot of things that can really be known conclusively at this point.


My Dear Wife and I are just back from the RiteAid #1 shot Moderna. No blood clots, just happy to finally get the jab.


Germany has been giving this vaccine to younger people. It is rumoured that women in their 30s taking the pill may be very over-represented in the numbers presenting with blood clots.

Someone I know said they’d looked into this and it was being reported locally (with an implication that this possible contra-indication was being looked into), but I cannot find such reports right now, so it may be mere rumour and innuendo. On the other hand it may explain an otherwise very strange occurrence.


seven deaths from 18.1m doses

2.8 million dead from COVID-19, and counting. Get the vaccine.


Please don’t start this British tabloid discourse here as well.

Are you actually, honestly, proposing that the EMA, one of the world’s most important health agencies, is stopping a vitally important vaccine to stick it to a private company?


The facts are that a link between the AZ vaccine and cerebral sinus venous thrombosis has been established by a German and a Norwegian team independently. It disproportionately affects young women so it only makes sense to give other vaccines to this group.

Even the UK is considering restricting the vaccine to groups who aren’t vulnerable to this side effect. The US, remember, never even authorised the use of the AZ vaccine.

This has absolutely nothing to do with antivaxers or vaccine nationalism. It’s a bunch of scientists saying that they recommend that a certain group take another vaccine because there’s a slight chance they might experience serious side effects otherwise.

This is a perfectly logical step and only means vaccines are being shuffled around, not stopped.

Source for German/Norwegian finding, reported a week ago and somehow never made a splash in the English speaking world:

Source for UK considering same steps as EU countries:

Edited for spelling and language


Nobody at the EMA says don’t get it. Quite the opposite.


It’s worse than that! Here’s a far right English newspaper reporting concerns:

Now I wouldn’t take my scientific advice from the Torygraph, but it isn’t just those nasty mainland Europeans . Also worth noting the EMA is only just out of London a wet weekend.


My Cardiologist and GP concur: Risk of Covid complications is much higher than risk of thrombosis from the Astra Zeneca vaccine right now.

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This is where the “do no harm” command really seems to do a lot of harm.

I don’t doubt that there is some connection between AZ and clotting, but when the risks between taking the vaccine and not taking the vaccine differ by a factor of a 100x-1000x, I think it’s pretty safe to quickly look at the numbers and simply say that these are acceptable casualties.

As it is, Europe’s reaction through the delay of the vaccine and more importantly the massive increase in vaccine hesitancy will probably kill 100x more than would perish through the vaccine and will condemn a 1000x that to long, costly illnesses with possible permanent side-effects.

“Do no harm” indeed. More like “protect myself because allowing thousands to die by inaction is preferable to being actively involved in the death of dozens.”

And no, it’s not an easy position to be in. But if you’re not willing to make life and death decisions (and I probably would not be), then you should resign a position that requires you to do so.


There’s way too much panic and not enough data right now.

There do appear to be more than the background cases of venous sinus thrombosis (1 year’s worth already, per one report i read, that i can no easily find right now).

This appears to occur in a sub-population within the vaccinated population (females of some age group, depending one what you read).

It appears to be occuring only in some countries.

It appears to be age related, maybe.

Coud it be a reporting problem in the countries without those numbers? Could it be a non-causative anomaly (remember the worry about BNT162b2 and bell’s palsey?). Could it be a real effect (with no current causative mechanism)? Could it be related to the known risk of DVT/PE in fertile women on birth control? Could it be space aliens?

Also, remember the old adage about Correlation & Causation.

This merits serious study, but not the horrid reporting going on in this world, and not the panic among health authorities.

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Didn’t two independent groups announce a potential mechanism over a week ago? They could be wrong, of course, but the fact that these groups arrived at this conclusion working independently of each other certainly makes it seem like it’s worth paying attention to.


With their statement, however you feel about it, they clearly do contribute to people not taking the vaccine.

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The thing is: these people are professional epidemiologists at the height of their careers. I am fairly certain they have heard of correlation and causation, being statisticians and all.

I wonder what you and others in this thread think they should have done? Lie? Ignore the science? I honestly don’t see what else anyone responsible in their situation could say that isn’t exactly what they have said: that there is a link and that they will come forth with advice on how to handle it shortly. It’s almost certain that this advice will be to restrict the AZ vaccine to demographics that aren’t affected and give other vaccines to those that are. That doesn’t mean that a single person stays unvaccinated that otherwise would be vaccinated. The vaccine strategy in most of Europe is centred around both AZ and Biontech, so alternatives are available (especially with Moderna and Curevac coming online soon as well)

Yes, there’s the argument that this will fuel antivaxx sentiment but they can’t just lie simply because of what idiots will think. That’s unethical to the highest degree and undermines trust into public health authorities even more. They have been asked and they have to give an honest answer.

And even if we disagree that this is the answer they should have given, even if we say they should have lied: surely we cannot say that they haven’t thought about it, that they, again: epidemiologists in a top position, haven’t understood the science?


Ps: a British team is now saying the same thing in case, and this is the vibe I’m getting in this thread, you don’t trust continental Europeans:

Prof Saad Shakir, the director of the drug safety research unit (DSRU) at Southampton University, said on Tuesday that the evidence accumulated in Europe and the UK of links between the vaccine and the rare blood clots “is consistent with causality”.

While the dangers of coronavirus were so great that vaccination must not stop, he said, measures should be put in place to reduce any extra risk to women under the age of 55, who seemed to be most affected. The DRSU has shared its analysis with the regulators.

ETA: I should clarify that I don’t think anyone in particular in this thread is thinking in these terms but rather that the discourse in the English speaking press is heavily skewed by the UK perspective, which has been shockingly one sided even in non-right leaning publications on the whole AZ situation.


This is apparently not the EMA’s official position but the opinion of an official expressed to an Italian newspaper.

It is not a question of trust, it is the litany of briefings against the vaccine in countries that we (and everyone) want and need to be protected. Officials and leaders have frequently undermined public confidence in vaccines (quasi-ineffective, banned for over 65s etc., etc.), some in nations which are already vaccine hesitant, combined with the stories of EU export blocks, uneven distribution and so on.

OK, this is exactly what I mean by the skewed British perspective.

This is the only point I will concede. Macron did say that AZ was quasi-ineffective for over 65 year olds when at the time it was stopped because there had been no trials that proved it was safe for over 65 year olds, which is not the same thing. However, that statement only made waves in the UK, out of a misunderstood sense of pride (or need to deflect from earlier failings in the pandemic). In France it was barely reported. Also, and I can’t stress this enough: countries in the EU are sovereign. What a national leader says doesn’t reflect on the entire project just as it doesn’t reflect on the G6 or the UN. (Source:)

As mentioned above that is simply an artefact of different regulatory cultures. At the time there was no evidence that it was safe on over 65 year olds so the EMA took longer to investigate than the UK authorities, which simply decided that their citizens should accept the risk.

No. Just no. Even if we want to call holding a company to account for their contractual obligations an export block, then this is only the EU catching up to what the US and the UK have practiced from the start of the pandemic. The UK still hasn’t exported a single vaccine, the US only a pittance to Canada and Mexico because they need to keep up appearances. Meanwhile the EU has exported more than half of its entire vaccine production, mostly to countries that don’t have their own, but also to the UK and US who don’t reciprocate. The EU made the mistake of thinking at the beginning of the pandemic that everyone would follow the rules of international solidarity. That didn’t turn out to be true so now they are playing catch up.

Edited for grammar only