AstraZeneca’s COVID vaccine more likely to cause thrombosis, study says

After the vaccination campaigns against COVID-19 started around the world, there were strange cases of thrombosis after the first doses, and a recent study revealed that the AstraZeneca biologist is one of those who have contributed the most cases to date.

The research he conducted British Medical Journal notes that vaccines against adenovirus COVID they were the ones that caused the most cases of thrombosis, and the main companies that make these biologics are AstraZeneca and Johnson & Johnson.

RNA COVID vaccines (such as Pfizer’s) meanwhile have had a smaller but still present presence of thrombosis cases, so there is less concern.

Research shows that “there is a causal relationship between these vaccines and thrombosis with thrombocytopenia syndrome, leading to the update of the product information for the AstraZeneca vaccine to include thrombosis with thrombocytopenia syndrome as a very rare side effect.”

The aim of the study was only to quantify the risk of thrombosis, since it is argued that the response to vaccines was the reason why COVID-19 reduced its mortality.

“After excluding many analyzes due to identified confounders or limited statistical power, we noted a 30 percent increase in risk thrombocytopenia after the first dose of ChAdOx1-S (AstraZeneca) compared to the first dose of BNT162b2 (Pfizer)”, concluded the study.

He also pointed out that the risk is higher in the first dose of the vaccine against COVID, and that the possibility of thrombosis does not increase in the second dose.


The investigation involved hundreds of thousands of samples taken from people who had been vaccinated mainly in Great Britain, the United States, Spain and Germany.

Global vaccination against COVID began on December 8, 2020 in the United Kingdom and then spread worldwide. The body’s response is something that is still being researched; Moreover, the study concludes that it is important to get this type of result to meet groups at risk of some vaccine-derived pathogens, two years after the start of immunization.

You can read the entire study at this link.

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