A new study has given more details about the “rare but devastating” blood clotting complications associated with the Oxford-AstraZeneca Covid-19 vaccine.
In a peer-reviewed paper published Wednesday in The New England Journal of Medicine, scientists from the Massachusetts Medical Society analyzed the first 220 cases of the condition reported in the United Kingdom.
The Oxford-AstraZeneca vaccine—now one of the most widely used Covid vaccines in the world—was rolled out in the U.K. in January, making it the first country to administer the shot.
A very small number of people who have been inoculated with the AstraZeneca vaccine have suffered blood clots. The condition, described by health experts as “extremely rare,” is characterized by blood clots accompanied by low platelet levels.
The Massachusetts Medical Society’s study used data from 294 patients who presented to U.K. hospitals between March 22 and June 6. Of those, 170 definite and 50 probable cases of the rare clotting—which scientists referred to as vaccine-induced immune thrombocytopenia and thrombosis—were identified.