Immunization once morest Covid-19 is suspected – in very rare cases – of exposing people to an increased risk of thromboembolic disease and thrombocytopenia.
The first results in the formation of clots in the veins or in a pulmonary embolism, if a clot comes to block the pulmonary artery. The second corresponds to a decrease in the number of blood platelets and an increased occurrence of bleeding.
To dig deeper into the subject, researchers conducted a study in Denmark, Finland and Norway, concerning the anti-Covid vaccines from the Pfizer-BioNTech, Moderna and AstraZeneca laboratories.
The cohort consisted of 265,339 patients hospitalized with coronary artery disease, bleeding disorders or cerebrovascular disease between 1is January 2020 and May 16, 2021.
An increased risk of cerebral thrombosis
With:
• AstraZeneca’s vaccine “increases the risk of cerebral venous thrombosis and thrombocytopenia”, reports Professor Jacob Dag Berild, lead author of the study;
• No significant association was observed for messenger RNA vaccines from Pfizer-BioNTech and Moderna.
History?
These risks of thrombocytopenia, but also of coagulation disorders, had been underlined by the National Medicines Safety Agency (ANSM), concerning the AstraZeneca vaccine, in a letter sent in March 2021 to health professionals.
Cases of thromboembolic disease and thrombocytopenia have in fact been described within 7 to 14 days following vaccination, particularly in women under 55 years of age.
But because of the very low incidence of these accidents, the ANSM reminds us that ” profits [de la vaccination] outweigh the risks, despite the very likely link with very rare cases of blood clots associated with low doses of platelets”.
When to consult?
If you have just been vaccinated once morest Covid-19, here are the symptoms that should lead you to consult if they occur in the hours or days following your injection: “shortness of breath, acute chest pain, swelling of the legs or persistent abdominal pain”, relays the ANSM.
Ditto if you experience, following vaccination, neurological symptoms such as “severe or persistent headaches, blurred vision”.
Source: Jama Network, June 14, 2022.
