AstraZeneca’s Covid-19 vaccine, made in collaboration with Oxford University has been found to raise the risk of vaccine-induced immune thrombocytopenia and thrombosis (VITT) – a rare but fatal blood clotting disorder, reports said.

“An unusually dangerous blood autoantibody directed against a protein termed platelet factor 4 (or PF4)” was found as the reason for VITT.

According to the scientists from Flinders University, Australia, who recently shared their study in the New England Journal of Medicine, VITT emerged in 2021 during the Covid-19 pandemic, particularly after the use of the Oxford-AstraZeneca vaccine, which is based on adenovirus vectors.

Scientists discovered that VITT is caused by a harmful blood autoantibody targeting a protein called platelet factor 4 (PF4). Separate research in 2023 revealed a similar, sometimes fatal disorder linked to natural adenovirus infections, such as the common cold, involving the same PF4 antibody.

Professor Tom Gordon from Flinders told IANS, “Indeed, the pathways of lethal antibody production in these disorders must be virtually identical and have similar genetic risk factors.”

He added that the “findings have the important clinical implication that lessons learned from VITT are applicable to rare cases of blood clotting after adenovirus (a common cold) infections, as well as having implications for vaccine development”.

AstraZeneca, in collaboration with The University of Oxford, had developed AZD1222 vaccine after the outbreak of the coronavirus in 2020. In India, it was manufactured and supplied under the name “Covishield” by Serum Institute of India (SII) through a licence from the university and the Swedish-British drugmaker.