The risk of developing a rare brain clot from Covid-19 is about eight times greater than from the AstraZeneca-Oxford vaccine, according to a new study.
Researchers at the University of Oxford, who are not linked to the vaccine, also found that people infected with coronavirus are “manyfold times” more likely than normal to develop the rare clotting disorder, known as cerebral venous thrombosis (CVT), where blood clots in the veins that run from the brain.
“There’s no doubt that Covid is a much greater risk of this [condition] than any of the vaccines,” said Professor Paul Harrison, a co-author of the study.
The research, which has yet to be peer-reviewed, drew comparisons between more than 500,000 Covid-19 patients in the US and 34 million people in Europe who have received the AstraZeneca vaccine, as well as the background level of CVT in the general population.
For Covid-19, the incidence rate of CVT stands at 39 cases per one million people, the study showed. But for a million people vaccinated with the AstraZeneca jab, there will be just five cases of CVT over a two-week period.