The World Health Organization endorsed the AstraZeneca COVID-19 vaccine after several European countries have halted its use over potential safety risks.
AstraZeneca has observed 15 deep vein thrombosis (DVT) reports and 22 pulmonary embolism (PE) cases out of 17 million vaccine recipients in the E.U. and U.K. as of March 8. Based on that data, the incidence rate among that population would be roughly 0.00022%. The company issued a statement saying the rate of events is “much lower than would be expected to occur naturally in a general population of this size and is similar across other licensed COVID-19 vaccines.
WHO stressed in prepared remarks that COVID-19 vaccines cannot “reduce illness or deaths from other causes” and that “thromboembolic events are known to occur frequently.”
Based on the data currently available, the agency said the benefits of the vaccine outweigh the risks.
The U.K.-based Medicines and Healthcare products Regulatory Agency reached similar conclusions, stating that there are no data suggesting a link between COVID-19 vaccination and increased blood-clot-related risk.
Dr June Raine, MHRA Chief Executive, said:
We continually monitor safety during use of all a vaccines to protect the public, and to ensure the benefits continue to outweigh the risks.
“Our thorough and careful review, alongside the critical assessment of leading, independent scientists, shows that there is no evidence that that blood clots in veins is occurring more than would be expected in the absence of vaccination, for either vaccine,” said Dr. June Raine, MHRA chief executive in a statement.
Raine did add, however, that MHRA has observed a limited number of reports of “an extremely rare form of blood clot in the cerebral veins (sinus vein thrombosis, or CSVT) occurring together with lowered platelets soon after vaccination.” The problem can also occur in unvaccinated individuals, as well as those who have COVID-19 disease.