Clear link between AstraZeneca vaccine and rare blood clots, EMA official | Hacker News Reader

Clear link between AstraZeneca vaccine and rare blood clots, EMA official

reuters.com

44 pointspseudolus49 comments

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I really hate this headline. From the article:

> very rare blood clots ... possible causes are still unknown

> Cavaleri provided no evidence to support his comment

> the benefits of the AstraZeneca shot outweigh the risks

> studies have found no higher risk of clots because of its vaccine

> A causal link with the vaccine is not proven

> many scientists say there is no definitive evidence

The EMA is investigating and has not announced any conclusions, but the headline seems to imply that they have.

Why can't they just put the anonymized data as a "click to download data" link if they can't provide any meaningful text about it?

Agreed, the link is anything but clear at this point in time.

>Cavaleri provided no evidence to support his comment.

I'm certainly willing to give a professional more attention than Joe on the street but I also expect some evidence or clarity on what would make him say that to go with those statements.

As far as I understood, the rate of even the rare clotting issue was still approximately at or below the expected background level. Has this changed?

No, it was always above the background level (at least in several EU member states) and this has not changed.

See e.g. German data from 3 weeks ago:

> The number of these cases after vaccination with COVID-19 AstraZeneca is statistically significantly higher than the number of cerebral venous thromboses that normally occur in the unvaccinated population. For this purpose, an observed-versus-expected analysis was performed, comparing the number of cases expected without vaccination in a 14-day time window with the number of cases reported after approximately 1.6 million AstraZeneca vaccinations in Germany. About one case would have been expected, and seven cases had been reported.

https://www.pei.de/EN/service/faq/coronavirus/faq-coronaviru...

Wouldn’t it make more sense to compare it to being injected with some other substance, instead of comparing it to “not being injected with anything at all”? I’m certainly no doctor, but I assume there is some risk associated with injecting a substance into the body. It would be very interesting to see the rate of similar blood clots for various vaccines/medications injected in the same manner as the AZ vaccine.

This is categorically misleading.

  > There is a link between AstraZeneca’s COVID-19 vaccine and very
  > rare blood clots in the brain but the possible causes are still
  > unknown, a senior official for the European Medicines Agency
  > (EMA) said in an interview published on Tuesday.

  > “In my opinion, we can now say it, it is clear that there is an
  > association (of the brain blood clots) with the vaccine. However,
  > we still do not know what causes this reaction,” Marco Cavaleri,
  > chair of the vaccine evaulation (sic) team at the EMA, told
  > Italian daily Il Messagero.

  > Cavaleri provided no evidence to support his comment.

So one senior member, albeit the chair of the vaccine evaluation team (but maybe that's cause for more concern), has said ahead of the official EMA announcement that in their _opinion_ there is a clear link and _there is no evidence_.

  > However, the EMA later said in a statement that its review of the
  > vaccine was ongoing and it expected to announce its findings on
  > Wednesday or Thursday.

  > In response to Cavaleri’s comments, the Amsterdam-based EMA said
  > in a statement on Tuesday: “EMA’s Pharmacovigilance Risk Assessment
  > Committee (PRAC) has not yet reached a conclusion and the review
  > (of any possible link) is currently ongoing.”

Can the title be changed here to reflect this is not yet the official stance of the EMA; it feels misleading.

Also I wonder how this bodes for Australia's vaccine rollout given we're using AstraZeneca.

It's not misleading at all, there is no doubt that there is a direct link between the AZ vaccine and these rare thrombosis cases. This link has been evidenced in several member states of the EU (see e.g. my sibling comment [1]) roughly three weeks ago.

What remains unknown is the mechanism that triggers this rare event. However, there are some promising theories and potential treatments!

[1] https://news.ycombinator.com/item?id=26713481

> there is no doubt that there is a direct link between the AZ vaccine and these rare thrombosis cases

Given that the article doesn’t say this, can you say why you are so certain?

Isn't the J&J almost identical and even made in the same factory [1] ? Wouldn't you also see this in J&J vaccine?

[1] https://www.google.com/amp/s/arstechnica.com/science/2021/03...

The J&J vaccine is due for availability in Europe in about 2 weeks. It's slightly over twice as expensive per shot as AZ, but AZ is a two shot vaccine and J&J is one shot so cost should be about the same.

Since this possible clotting issue with AZ seems to mostly affect younger people, maybe they could use J&J on younger people and AZ on older people?

The Paul Ehrlich Institute (German Federal Institute for Vaccines) has an excellent FAQ on the topic [1].

Here is the direct link to the statement from the German Society for Thrombosis Research that pioneers the idea of heparin-induced thrombocytopenia as an allergic reaction [2] (PDF, unfortunately in German).

[1] https://www.pei.de/EN/service/faq/coronavirus/faq-coronaviru...

[2] https://gth-online.org/wp-content/uploads/2021/03/GTH_Stellu...

While this issue is too rare to alter the current vaccine strategy - it does raise an interesting ethical question. What should we do if, for a specific segment of the population, the vaccine poses a greater risk than contracting the virus? Would interesting to try and model this. How would we would/could we chose between the rights of two different population segments?

We should develop a treatment. That's pretty much what we should have been doing all along. If we understand the mechanism of death, we should be able to formulate a protocol to stop/contain that mechanism.

> How would we would/could we chose between the rights of two different population segments?

What is there to choose between unless we force people to take the vaccine?

No one can force someone to take a vaccine - but the government can prevent people - or segments of the population - from taking it. By preventing one group taking it, due to health concerns, it may increase the spread of the disease in other more vulnerable groups. Preventing deaths in one group that result in more in another. I guess this is essentially a trolly problem: https://en.wikipedia.org/wiki/Trolley_problem

None of the coverage I've seen mentions the base rate of these blood clots. Without knowing that, the rate is so low that I could easily believe it's background noise being blamed on the vaccine.

That said, we have three other vaccines that are more effective and don't seem to have this problem (assuming it does exist). We don't need this vaccine.

You are significantly underestimating the experts working on evaluating these cases:

https://www.pei.de/EN/service/faq/coronavirus/faq-coronaviru...

> We don't need this vaccine.

I don't know who is "we", but we definitely do need this vaccine, because you are more likely to die in a car crash than from the AZ vaccine.

All I'm questioning is the quality of the news coverage. Thanks for adding details, no thanks for assuming I'm an idiot. And if we have three other vaccines that are all known to be more effective, why should anyone bother with the one that causes blood clots?

Apologies, I've misread your comment as 'experts didn't consider X', which to my surprise was a common pattern in the responses. You do clearly criticise the news coverage, not the experts.

I agree with you that loosing AZ is not a disaster, still we have a considerable shortage of vaccines in Europe, and giving AZ to a subset, say, men and women over 65, seems like a more reasonable solution.

https://twitter.com/TakethatCt/status/1379708839252070401/ph...

  pregnancy:         1 in  500
  combined pill:     1 in 1000
  recurrent flights: 1 in  300
  ICU with covid:    1 in   10

AZ vaccine: 1 in 500,000.

The UK has delivered millions of doses of the AZ vaccine and there have been tiny (fewer than 100) cases of blood clots.

The EMA has zero credibility when it comes to anything to do with AstraZeneca, the behavior of the EU throughout this entire ordeal has made it clear that this is a political hit job, regardless of the ultimate validity of any criticism on the vaccine.

We will need an independent agency to confirm or deny any such link, so hopefully the American/Chinese regulatory agencies will release their findings soon.

No. UK regulators are thinking of stopping AZ for all below 50. So, no, it's not political.

https://www.theguardian.com/world/2021/apr/06/ema-denies-alr...

Its like a game of ping-pong...

The roller coaster saga of AstraZeneca is a prime example of why I think it is fair for some people to not want to get vaccines or at least to be suspicious of the accelerated EUA process. The choice to get vaccinated or not should be retained by individuals, respecting bodily autonomy, rather than forced by states via vaccine passports or other such policies that resemble China's social credit scores.

Vaccine passports don't force you to take the vaccine, you are free to not get vaccinated and just not go to private crowded venues like disneyland or whatever.

Also, what about the bodily autonomy of people that don't want to be in close proximity someone who might have covid? (after all, vaccines are only 65-95% effective, perhaps a little less when it comes to new variants). This is just inevitably one of those cases where an individual's own freedom can actively inhibit other people's freedom, there's no perfect solution.

We've also had similar travel requirements for other diseases for decades without issue. Want to hop on an international flight in the late 1940s? Better have your smallpox vaccine recorded!

https://en.wikipedia.org/wiki/Vaccination_requirements_for_i...

> what about the bodily autonomy of people that don't want to be in close proximity someone who might have covid

They can choose to isolate themselves. The big wide world is full of risks, and COVID is but one.

If you choose to get vaccinated, you have little to worry about. You're not going to get sick, even if exposed. If I choose to not get vaccinated, I theoretically endanger myself and that's my choice.

> If you choose to get vaccinated, you have little to worry about.

I might need the ICU that's filled to the brim with anti-vaxxers. (There are also folks who can't get vaccinated who rely on the responsibility of others.)

> The choice to get vaccinated or not should be retained by individuals, respecting bodily autonomy,

> rather than forced by states via vaccine passports

People should definitely have the choice whether to be vaccinated or not. This does not mean that they do not have to bear the consequences of that decision. This might well mean that they cannot travel as easily as before or might not even visit restaurants because of the threat that they still pose to others. I understand that they might not like that but this feels like a case of "wanting to have the cake and eating it".

If unvaccinated people pose a threat to the vaccinated, what exactly is the benefit of the vaccine then?

> If unvaccinated people pose a threat to the vaccinated, what exactly is the benefit of the vaccine then?

Unvaccinated pose a threat to other unvaccinated people. There are people who just cannot be vaccinated whether they want to be or not.

So why can't those people just isolate themselves or where PPE everywhere if they are risk averse? Why force others to inject something foreign rushed through authorization into their body?

At this point, it's clear we don't know precisely what the risks are, thus it's not possible to say the 'risks' outweigh the benefits, and the product should be pulled.

It's unclear what level of side effects or potentially deaths would have to be in order for the product to be removed from the market. If it was another class of drug, it would have been removed by now.

They mention 44 clots out of 9.2mm doses given

Lots of medications have risks. For example, a common birth control can cause or increase risk of pulmonary embolisms.

Unless there's reason to think the actual rate will become much higher than 1-in-200k people, it seems like you could make a decision on trade-offs. Covid has killed many many more people already. I'm sure we'll uncover risk factors that'll help us avoid higher risk populations too, further decreasing risk.

It should be noted that the risk for blood clots from birth control is much higher, yet seems to be within the bounds of what is acceptable.

Quick google search:

> Out of every 10,000 women taking birth control pills, 3 to 9 of them will develop a blood clot.

Also, for scale:

> Out of every 10,000 women in the first 12 weeks after giving birth, 40 to 65 of them will develop a blood clot.

https://www.healthline.com/health/birth-control/pulmonary-em...

For what it's worth I've read that under today's circumstances birth control would not have received marketing approval.

See also:

> Birth control pills can also cause thrombosis. So why is there all the fuss about the COVID-19 Vaccine AstraZeneca?

> It is true that for birth control pills thromboses, even with fatal outcome, are known as a very rare side effect. They are listed in the Summary of Product Characteristics (SmPC). The birth control pill is available only on prescription. Every woman must be informed of this risk by the prescribing physician. For the COVID-19 Vaccine AstraZeneca, there is currently a suspected very rare side effect of sinus vein thrombosis with accompanying platelet deficiency, sometimes fatal. It is not listed in the SmPC.

> The consideration of whether the vaccine can continue to be used even though it may cause this very rare side effect (if necessary, after this risk has been added to the SmPC) will be made at the European level by the European Medicines Agency (EMA) and at the national level by politicians. The procedure has been initiated.

https://www.pei.de/EN/service/faq/coronavirus/faq-coronaviru...

> Birth control pills can also cause thrombosis. So why is there all the fuss about the COVID-19 Vaccine AstraZeneca?

Taking birth control pills is entirely a matter of personal choice. The COVID vaccines, even if not strictly compulsory, are certainly being pushed hard, with threats of curtailing freedom of movement if you choose to not get one.

How can someone make an informed decision with so many unknowns? Also, what would it take for the product to be pulled? Is there a clearly established rate of side effects?

The death rate for my age group where I'm located based on government data is 1.1 deaths per 1k cases, with less than 1000 deaths total. This seems statistically insignificant to me, I would wager half or more of these cases had a different leading cause of death.

Compared to 2018's flu death rate, based on CDC's wildly inflated 'assumed cases' number, the death rate of covid is 10x that of the flu, based on the reported cases of covid. Considering covid cases are likely extremely under reported as the vast majority of cases are asymptomatic, they're probably about the same.

At this point, there's not enough data to convince me it's safer than getting the wild virus.

Let's do a worst case calculation and assume you are a women aged 30.

The infection fatality rate of Covid for this age and gender is 0.01 % or 1 in 10k (based on seroprevalence data not test data [1]).

The fatality rate for the AZ vaccine in Germany is 1 in 200k, so you are 20 times more likely to die from Covid.

You are correct that there is (and always will be) some uncertainty around the risks of the vaccine, but the same is true for Covid. Interestingly the vaccine is only appr. 6 months older than Covid (Nov 2019 vs Apr 2020) but more people have had Covid than vaccines. Still, uncertainties around Covid remain, e.g. we don't know the prevalence and severity of long Covid.

[1] https://www.nature.com/articles/s41586-020-2918-0/figures/2

Seems for the hypothetical person, covid mortality is no higher than background mortality.

Yes, this was one of the surprises early on that Covid risk matches background risk relatively closely [1].

Which is not a good thing, especially on a societal level, when you have this one thing killing people at the rate of all other things combined.

[1] https://www.bbc.co.uk/sounds/play/p087x9sf

While the risks for AZ vaccine are not yet 100% clear, more and more younger people are dying from the Covid-19.

In poor countries and some parts of Europe the vaccine availability is scarce. So everyone should decide for themselves

(I've received my first shot of AZ, not exactly young, not exactly old, but I'll take my chances vs Covid)

> unclear what level of side effects or potentially deaths would have to be in order for the product to be removed from the market

I'm not familiar with EMA procedure. But with the FDA, it's clear. Entire rule books about the risk ratios clear. Billions of dollars spent on tuning those risk ratios to every demographic clear.

44 reported out of 9.2 million. As many as Germany has Covid cases every 9 minutes [0]. Nearly half of Britain has received at least one shot [1], compared to the EU, which has struggled to get to a double-digit rate [2].

This is a low-frequency alleged side effect that should be investigated. But the matter's narrow impact, ambiguity and timing, right after the EU's inability to procure and distribute vaccines came to light, is convenient.

[0] https://www.nytimes.com/interactive/2020/world/europe/german... 44 / [6,855 cases on 5 April / (24 hours * 60 minutes per hour)]

[1] https://coronavirus.data.gov.uk/details/vaccinations

[2] https://graphics.reuters.com/HEALTH-CORONAVIRUS/EU-VACCINES/...

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