“Sweden, home of AstraZeneca, joins other European countries in suspending use of its vaccine”
Sweden’s Public Health Agency has suspended the use of the AstraZeneca coronavirus vaccine citing the ongoing investigation by the European Medicines Agency into any connection with blood clots.
The move comes after Sweden originally declined to follow its Nordic neighbors Denmark and Norway in halting use of the vaccine after suspicions that it could be linked to some fatal cases of blood clots.
On Thursday, Swedish authorities argued that no link had been found between the vaccine and the blood clot cases, a finding that has been echoed by the EMA, the World Health Organization and AstraZeneca itself, which is partly based in Sweden. In a press release, the country’s state epidemiologist Anders Tegnell said it was a “precautionary” measure.
On Monday, four of Europe’s most populous countries followed Denmark in suspending the use of the vaccine, including Germany, France, Italy and Spain. Ireland and Indonesia have also done so.
Australia and Britain, home of Oxford University, which helped develop the vaccine, have reiterated their faith in its safety and effectiveness.
WHO officials are still recommending the vaccine, and they said Monday that the greatest threat facing countries is a lack of access to vaccines — not blood clot concerns. Canadian Prime Minister Justin Trudeau, whose health officials have approved the AstraZeneca shot, called it “safe and effective.” The company has said there is no evidence of a link between its vaccine and clotting.
The International Society on Thrombosis and Haemostasis, which is concerned with blood clotting-related ailments, recommended that adults continue to use the vaccine because “the small number of reported thrombotic events relative to the millions of administered COVID-19 vaccinations does not suggest a direct link.”
Risk is one of those things, I tell you what.
Kinda surprised, honestly.Report
“Better that ten people die from the disease than that one person die from the cure.”
–Drug regulatory agencies
Although this is probably overly charitable; my understanding is that these adverse events are not occurring at higher rates than would generally be expected, so it’s not clear that there’s any good reason to suspect a causal relationship.Report
What did the trials show?
“Someone took a medicine and something bad happened! Did the medicine cause or contribute to it?” is the supposed of thing that trials are supposed to answer. If the trial was done well, we should know if the vaccine caused or contributed to the blood clots. If it did, we should have an idea of what frequency we can expect to see blood clots arising in those who receive the vaccine. And we’d have some idea of whether there are risk factors. This is why trials are done.
Now, the novelty of Covid-19 and of these vaccines means there is going to be more uncertainty that with most medicines because we simply don’t have the time to observe for long-term or even really medium-term effects. It is a bit of a dice roll. But if folks are having blood clots within days or weeks of receiving the vaccine, the trials should have data on that.Report
Quoting from an article at the Telegraph:
By the way, phase III clinical trials rarely have, and generally can’t reasonably be expected to have, the statistical power needed to catch rare side effects. Drugs are continually monitored for adverse events after they go to market, which is sometimes referred to as phase IV.Report
Exactly. And the medical community in Europe seems to be genuinely puzzled by whatever the politicians think they are accomplishing other than letting people die of Covid-19 unnecessarily.Report
Thank you.
So, it would seem I was somewhat off in the ability of clinical trials to capture such rare side effects. However, it would seem there isn’t real reason to be concerned about negative effects of the AZ vaccine and that its use shouldn’t be determined based on blood clot fears.Report