• Covid: Ema, review on AstraZeneca monoclonals

  • Ema: no evidence on second dose thrombosis risks AstraZeneca

  • Ema, the AstraZeneca vaccine is valid for everyone

  • Vaccinated with AstraZeneca, 54 years old dies of thrombosis.

    Power of attorney will acquire medical records

  • The CTS towards the recommendation of the AstraZeneca vaccine to the over 60s, but the crux of the recall remains

  • Australia, woman dies of thrombosis: vaccinated with Astrazeneca

  • Vaccine, Aifa: "Second dose AstraZeneca is safe"

Share

02 December 2021 A team of scientists in Wales and the US believe they have found "the trigger" of the extremely rare blood clots after the administration of the Astrazeneca vaccine.



The team, according to reports from the BBC, has shown in detail how a protein in the blood is attracted to a key component of the vaccine devised in Oxford, triggering a chain reaction that involves the immune system and which can culminate in dangerous clots.



Alan Parker, one of the

Cardiff University

researchers

, told the BBC: "What we have is the trigger, but there are a lot of steps that have to happen next."



The study was published in the journal Science Advances. "Although the research is not definitive, it offers interesting insights and AstraZeneca is exploring ways to exploit these findings as part of our efforts to remove this extremely rare side effect," explained a spokesman for the Anglo-Swedish pharmaceutical company.



L '

University of Oxford

however declined to comment on the research. According to AstraZeneca, its vaccine has saved more than a million lives worldwide and prevented 50 million Covid cases. But in the wake of cases of blood clots, albeit rare, the use of this type of vaccine around the world has been reduced, and vaccines using more modern technology are now used for boosters, with the Mrna messenger.



A spokesperson for AstraZeneca stressed that thrombosis cases occur more frequently if one is infected with Covid than the Anglo-Swedish serum vaccine and that the reasons for these events have not yet been established. Research published in the scientific journal

Science Advances

reveals that the outer part of adenovirus, the viral vector used in the AstraZeneca Covid vaccine, attracts the platelet factor four protein like a magnet.



To detect this reaction, the scientists used a technique called a

cryo-electron microscope

which allows to have images of the adenovirus at the molecular level.

Professor Alan Parker, one of the Cardiff University researchers told BBC that it is a difference in magnetic potential between the adenovirus which "has a strongly negative surface and the reversed factor four of the extremely positive platelets" that triggers the reaction. .

"What we have is the trigger, but there are many other factors that come after."