Deutsche Welle (English edition)
AstraZeneca: What's the deal with thrombosis?
Cerebral venous sinus thrombosis has led to the administration of the AstraZeneca vaccine being halted in many countries. But what exactly are these thromboses? And was the decision to halt the vaccine too hasty?
As of Wednesday, March 31, the AstraZeneca vaccine will no longer be administered to people under the age of 60 — that was the decision reached by the health ministers of Germany's federal and state governments following a recommendation by the country's Standing Committee on Vaccination (Stiko).
Of the 31 cases of rare thrombosis reported to the Paul Ehrlich Institute in Germany, it was determined each person had recently received the AstraZeneca vaccine. In nine cases, the outcome was fatal.
Here's what's known so far about the connection between the two:
Blood clotting in the brain: What exactly was observed?
According to the current status of vaccination monitoring by the Robert Koch Institute (RKI), a German government agency responsible for disease control and prevention, 31 cases
of cerebral venous sinus thrombosis (CVST) occurred from 2.7 million first and 767 second doses of the AstraZeneca vaccine. At the same time, 19 of the affected individuals were also found to be deficient in platelets, which can affect blood clotting.
However, this type of thrombosis is considered rather rare, looking at its incidence — it is estimated that two to five people per 1 million experience CVST over the course of a year. However, recent studies indicate a higher number of people affected. As many as 15.7 cases per million people each year have been reported in an Australian study, says Paul Hunter, a professor of medicine at the University of East Anglia in the United Kingdom. That would mean the current incidence is underestimated by four to eight times, according to Hunter.
Does thrombosis always equal thrombosis?
Since Germany's Health Minister Jens Spahn announced a pause in AstraZeneca vaccinations in mid-March, there has been much discussion had — especially on social media. There were many angry responses: why is the contraceptive pill still being prescribed to women, even though it is known that roughly 1,100 women will suffer thrombosis among every 1 million who take it. In comparison, why do authorities throw the entire vaccination strategy out the window after only seven