Researchers in Norway and Germany say they’ve identified antibodies that provoke immune reactions leading to the type of cerebral blood clots experienced by some people who received AstraZeneca’s COVID vaccine.
Researchers at the Greifswald teaching hospital in northern Germany said Friday they’ve discovered how the AstraZeneca COVID vaccine could cause blood clots that could lead to rare thrombosis in the brain, public broadcaster Norddeutscher Rundfunk reported.
The German team, led by professor Andreas Greinacher, said in a statement that AstraZeneca’s vaccine may, in some cases, prompt overactivation of platelets in the blood, which can lead to potentially deadly clots. As NPR reported, Greinacher said it’s similar to what happens with a condition called heparin-induced thrombocytopenia.
Greinacher and his team analyzed 13 cases of cerebral blood clots reported in Germany within 4 – 16 days of administration of the AstraZeneca vaccine. Twelve of the 13 cases were women and almost all were under the age of 55. In four of the 12 patients, the team was able to isolate and identify the specific antibodies that provoked the immune reaction leading to the cerebral blood clots.
The researchers found that AstraZeneca’s vaccine activates blood platelets, or thrombocytes, which typically only happens in the body when a wound is healing –– when the blood coagulates as the wound closes. In some patients, the vaccination activated a mechanism that caused blood clots to form in the brain, according to Deutsche Welle.