The European Medicines Agency (EMA) explained this Wednesday at a press conference that they have found a possible link between some thrombi and the use of the Oxford and AstraZeneca vaccine, Specially in women under 60 years of age with platelet deficiency within two weeks of vaccination. It is “a possible relationship with very rare cases of unusual blood clots with low platelets,” the EMA noted in a press release prior to public explanation. For now, continue to investigate how this possible relationship works, but they insist on the safety of the vaccine for people who do not fall into this group.
“The EMA confirms that the overall risk-benefit ratio remains positive,” he said. Emer Cooke, Director of the EMA. “Vaccination against COVID-19 is necessary due to the situation in which we find ourselves and we must have all the vaccines that we have.”
«COVID-19 is associated with a risk of hospitalization and death. The reported combination of blood clots and low platelets is very rare, and the overall benefits of the vaccine in preventing COVID-19 outweigh the risks of side effects, “the agency explains in the press release. “It is very important that we get vaccinated to fight this disease,” said Director Cooke.
Thrombosis and vaccination AstraZeneca
The data that the EMA has to date is that most cases of thrombi have occurred in women under 60 years of age within two weeks of immunization with the AstraZeneca vaccine. That is why they ask that people be vigilant for this rare side effect and seek medical assistance if symptoms occur as’ difficulty breathing; chest pain, leg swelling; persistent abdominal (belly) pain, neurological symptoms, such as severe and persistent headaches or blurred vision; small spots of blood under the skin beyond the injection site. ‘
Although the majority of cases have occurred in people under 60 years of age and women, “due to the different ways in which the vaccine is used in different countries, the PRAC did not conclude that age and sex were factors of clear risk«
Sabine Straus, president of the Pharmacovigilance Risk Assessment Committee
Although for the moment this relationship has only been found with women, the EMA could point out that it is not something exclusive to them: “Although most of the cases occurred in people under 60 years of age and in women, due to the different ways the vaccine is used in different countries, the PRAC did not conclude that age and gender were clear risk factors for these rare side effects, “he explained at a press conference Sabine straus, President of the Pharmacovigilance Risk Assessment Committee (PRAC).
Due to this possible link between the AstraZeneca vaccine and thrombosis, the EMA has decided to add ‘unusual blood clots with low platelets’ as very rare side effect of Vaxzevria. This is the new name for the vaccine from the University of Oxford and AstraZeneca. “In reaching this conclusion, the committee has taken into account all currently available evidence, including the advice of an ad hoc group of experts.”
The EU will make a decision soon
Now, the member states of the European Union have to decide, with the data in hand, whether to continue administering this vaccine to their citizens. But to do this they must take into account this possible relationship between thrombi and the AstraZeneca vaccine. And that occurs in very few cases. So, immunization of people with platelet deficiency with AstraZeneca vaccine remains in the air, pending the agreement of the member states that will meet shortly.
In the UK already 18 million people have been vaccinated with it. And only 30 cases of thrombosis have been reported that could be related to the AstraZeneca vaccine. We now know that platelet deficiency appears to be behind these thrombotic events.
What is platelet deficiency?
Photo by Cassi Josh on Unsplash
Platelet deficiency, better known as thrombocytopenia, «Is a condition in which the body has few platelets«, They explain from the Mayo Clinic. “Platelets (thrombocytes) are colorless blood cells that are involved in blood clotting.” “Platelets clump together and form plugs in blood vessel lesions to stop bleeding,” they add. Nevertheless, when a person has a low platelet count, bleeding from wounds does not stop or it costs more to stop.
What can cause thrombocytopenia? Platelet deficiency ‘can occur as a result of a bone marrow disorder, such as leukemia or a immune system problem. Or, it can be a side effect of certain medications«; Platelets may also decrease due to viral infections or excessive alcohol consumption. In addition, if it is mild it hardly causes symptoms and “very rarely, the number of platelets can be so low that dangerous internal bleeding occurs.” Fortunately, thrombocytopenia can be treated.
Thrombocytopenia, key in these cases
“A plausible explanation for the combination of blood clots and low platelets is an immune response, leading to a condition similar to that sometimes seen in heparin-treated patients.”
The EMA has tried to respond to this rare possible combination that produces thrombi as a side effect of the AstraZeneca vaccine. “A plausible explanation for the combination of blood clots and low platelets is a immune response, leading to a condition similar to that sometimes seen in heparin-treated patients (heparin-induced thrombocytopenia, HIT). The PRAC has requested new studies and modifications of those that are in progress to provide more information and will take any other necessary measures ”, indicated the EMA.
In the case of people who have suffered thrombosis due to the possible relationship between platelet deficiency and the Oxford University and AstraZeneca vaccine; thrombi have occurred ‘in the veins of the brain (cerebral venous sinus thrombosis, CVST) and the abdomen (splanchnic vein thrombosis) and in arteriesalong with low levels of blood platelets and sometimes bleeding«Says the EMA.
The EMA will continue to investigate. Monitoring for side effects, like this one, is part of your job: once a drug or vaccine goes on the market, it is still under constant surveillance by the EMA. If there are problems, it is withdrawn. Or if very rare side effects are found, they are investigated and advised in the package insert. It is no different with the possible relationship between thrombi and the AstraZeneca vaccine, it is still being investigated.
(More information soon)