Very rare blood clots found in patients who tend to be women younger than 60 may have a “possible link” to AstraZeneca’s COVID vaccine, the European Union’s drug regulator said Wednesday.
The European Medicines Agency said the vaccine “may trigger an immune response” that leads to the clots, but it’s still too early to say for certain.
The regulator declined to impose any new age restrictions on the vaccine’s rollout, stressing “the overall benefits of the vaccine in preventing COVID-19 outweigh the risks of side effects.”
In the U.K., meanwhile, regulators said people younger than 30 should be given the choice of another product.
“The reported cases of unusual blood clotting following vaccination with the AstraZeneca vaccine should be listed as possible side effects of the vaccine,” EMA Executive Director Emer Cooke said Wednesday.
“The risk of mortality from COVID is much greater than the risk of mortality from these side effects,” Cooke said.
The EMA reached its conclusion after studying 62 cases of cerebral venous sinus thrombosis and 24 cases of splanchnic vein thrombosis reported as of March 22 in Europe and the U.K., where roughly 25 million people have received the AstraZeneca vaccine.
The agency said most of the cases occurred in women younger than 60 within two weeks of vaccination.
Healthcare professionals should tell people receiving the AstraZeneca vaccine that they should seek medical attention if they develop certain symptoms of clots, the EMA said.
The symptoms include shortness of breath, chest pain, leg swelling, persistent abdominal pain, persistent headaches and blurred vision, the EMA said.
Last month, several countries suspended their use of the AstraZeneca vaccine over the clot issue but most restarted the use after the EMA said the greater danger was not using the potentially life-saving vaccine.
“We can’t afford not to use this vaccine if we are going to end the pandemic,” Dr. Peter English, who formerly chaired the British Medical Association’s Public Health Medicine Committee, said, according to the Associated Press.
AstraZeneca’s shot is cheaper and easier to store than the vaccines from Moderna and Pfizer-BioNTech, making it a pillar of the U.N.-backed program known as COVAX that aims to get vaccines to some of the world’s poorest countries.
It has been endorsed for use in more than 50 countries, though drug regulators in the U.S. are still evaluating the vaccine.
