Update: more on this in a later post here.
Everyone will have heard of the situation in Europe right now, with a whole list of countries suspending dosing of the AstraZeneca/Oxford vaccine. Sweden and Latvia joined that list today .But getting clarity on this is another thing entirely.
I have not been the biggest fan of the vaccine, because its initial rollout was (frankly) botched. It was difficult to figure out how efficacious it was, and that confusion persisted after further attempts to clear things up. The last figure I’ve seen is that the European Medicines Agency estimates the vaccine to be about 60% effective, and at the same time the EMA does not see safety concerns with it. But there are many member states of the EU who apparently disagree, citing reports of blood clotting problems and/or thrombocytopenia after dosing.
I think that there are several distinct levels to this problem. The first, obviously, is medical. The big question is, are the reports of vascular problems greater than one would expect in the vaccinated population as a whole? It’s not clear to me what the answer is, and it may very well be “No, they aren’t”. That CNBC link above quotes Michael Head at Southampton as saying that the data so far look like the problems show up at at least the same levels, and may even be lower in the vaccinated group. AstraZeneca has said that they’re aware of 15 events of deep vein thrombosis and 22 events pulmonary embolisms, but that’s in 17 million people who have had at least one shot – and they say that is indeed “much lower than would be expected to occur naturally in a general population of this size“. It also appears to be similar to what’s been seen with the other coronavirus vaccines, which rather than meaning “they’re all bad” looks like they’re all showing the same baseline signal of such events across a broad population, without adding to it.
In that case, this could be an example of what I warned about back in December (and many others have warned about as well), the post hoc ergo propter hoc “false side effects” problem. I’ve been looking this morning, and so far have not found anyone clearly stating that the problems seen are running higher in the vaccinated patients, anyway (if someone does come across such numbers or such a statement, I’ll amend this post immediately with a link). I realize that there’s a possibility (not a likely one, though) that some particular batch of vaccine is more problematic, but I haven’t seen any solid evidence of that, either
The second half of the medical problem is naturally what happens when you suspend dosing of what is, in many cases in the EU, the only vaccine available. We’ve been seeing cases falling here in the US ever since a peak on the first week of January – many of us were worried about what might have been a rise in February but which now just seems to have been a plateau, with cases continuing to drop since then. But many European countries are definitely seeing another wave of infections, and the EU case numbers as a whole are going in the opposite direction to the US ones. There are surely a lot of reasons for this, with new viral variants being one, slow vaccine rollouts being another, and now complete vaccination halts set to add even more. Put as bluntly as possible, even if the AZ/Oxford vaccine has these side effects (which again, I don’t see any evidence for yet), you are still very likely to kill more people by not giving it.
The next problem is a regulatory one. The EMA and the World Health Organization continue to endorse the vaccine, but that seems to mean little or nothing as one European country after another shuts down its use. I understand that the EMA does not have supranational authority in these matters, but there must be people there wondering what good their recommendations and regulatory approvals do, if this is how they can be dealt with. The EMA itself is meeting on Thursday for what should be some stressful discussions. Meanwhile, there are other countries (such as Belgium) whose authorities (so far) say that they see no need to stop using the vaccine at all.
It’s a mess. And it’s a mess that leads us right into the third problem, which is public confidence. The AZ/Oxford vaccine has been in trouble there since the day the first data came out. The efficacy numbers looked lower than the other vaccines that had reported by then, and as mentioned, the presentation of the data was really poorly handled and continued to be so for weeks. Now with these dosing suspensions, I have to wonder if this vaccine is ever going to lose the dark cloud it’s currently sitting under. Even if EU countries start dosing again in a few days, what are people going to think? And this fear and uncertainty can spill over into hesitancy for all the vaccines, of course, and that’s the last thing we need.
We’re about to get another batch of data, for better or worse. Reports are that the US trial of the vaccine has reached its events threshold, so we’ll be seeing completely new clinical efficacy numbers for this vaccine soon. That will be very interesting indeed – and while most of us were waiting to see what those efficacy figures would look like, now everyone will be looking at the safety numbers as well. I do not expect the vaccine to show any bad safety signals at all, let me say up front (I mean, it’s already been dosed 17 million times; that’s a bigger data set than any trial could ever give you). But will that matter to people who are scheduled to get it? Will it matter to the countries who have suspended dosing?
Let’s say that the efficacy numbers come in at a solid, inarguable 60%. You would want to see a higher number in a better world, but 60% is a damn sight better than not getting vaccinated at all. Which is effectively what a number of European countries have chosen to do instead. If I were living in one of those countries where the cases are heading right back up, I would bare my arm immediately for a 60% effective vaccine and hope that as many other people as possible did the same.