Two highly concerning papers now live in the New England Journal of Medicine regarding the adenovirus-based AstraZeneca/Oxford vaccine.
A small number of patients appear to have had serious clotting events with implications.
🧵
nejm.org/doi/full/10.10…
nejm.org/doi/full/10.10…
A small number of patients appear to have had serious clotting events with implications.
🧵
nejm.org/doi/full/10.10…
nejm.org/doi/full/10.10…
First, the top-line findings are concerning.
In Germany and Austria, 11 patients developed clotting problems and of these 6 died. The median age was 36.
In Norway, 5 had the condition, 3 died.
Some if not many of these patients were previously healthy.
In Germany and Austria, 11 patients developed clotting problems and of these 6 died. The median age was 36.
In Norway, 5 had the condition, 3 died.
Some if not many of these patients were previously healthy.
Keep in mind that in these nations, several million AZ doses have been given.
So this is rare.
But, it looks real.
There's a well described bio-molecular explanation described in these papers that is plausible and consistently measured here.
Impressive and important work.
So this is rare.
But, it looks real.
There's a well described bio-molecular explanation described in these papers that is plausible and consistently measured here.
Impressive and important work.
The way it is being described, it is similar to other rare conditions, caused by medications that thin the blood (heparin-induced thrombocytopenia).
The researchers are calling this vaccine-induced immune thrombotic thrombocytopenia (VITT).
The researchers are calling this vaccine-induced immune thrombotic thrombocytopenia (VITT).
The issue of course is that we need to know how common this is *versus* serious COVID.
In young and middle aged adults, COVID has a mortality rate that may be 1 in 1000.
We do not know how rare THIS condition is.
It is likely far MORE common than severe COVID in this age group
In young and middle aged adults, COVID has a mortality rate that may be 1 in 1000.
We do not know how rare THIS condition is.
It is likely far MORE common than severe COVID in this age group
Given that, here's my take on "what I'd do myself":
Option 1: AstraZeneca vs nothing. I'd STILL chose the vaccine. My odds of COVID-related illness are still way greater than a rare VITT event.
Option 2: AstraZeneca vs other vaccine: I'd specifically chose another vaccine.
Option 1: AstraZeneca vs nothing. I'd STILL chose the vaccine. My odds of COVID-related illness are still way greater than a rare VITT event.
Option 2: AstraZeneca vs other vaccine: I'd specifically chose another vaccine.
One interesting point here is that there now appears to be a fairly reliable way to TEST for this (after it occurs). There's no current way to predict who might be at risk.
There are also treatment options, with varying degrees of success.
There are also treatment options, with varying degrees of success.
Lastly, I am confident that this is both real AND rare.
Why?
Because the trials were large.
They did not pick this up.
If they had, we'd know that this was more common.
It was detected only after scale-up (millions of doses, not tens of thousands)
That reveals a lot.
Why?
Because the trials were large.
They did not pick this up.
If they had, we'd know that this was more common.
It was detected only after scale-up (millions of doses, not tens of thousands)
That reveals a lot.
This shows us why we need very close post-trial surveillance AND a variety of vaccine options.
These vaccines have and will save millions of lives.
But this process won't be without its setbacks.
As setbacks go, this is important, but statistically still small.
More soon.
These vaccines have and will save millions of lives.
But this process won't be without its setbacks.
As setbacks go, this is important, but statistically still small.
More soon.
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