Relationship between blood clots and COVID-19 vaccines: A literature review

Abstract

SARS-CoV-2 pandemic is one of the most critical pandemics during human civilization. Several therapeutic strategies for COVID-19 management have been offered; nonetheless, none of them seems to be sufficiently beneficial. In effect, vaccines have been proffered as a viable option. The critical issue now is to concentrate on protecting individuals against illness through immunization. One of the causes for concern among the researchers, physicians, and generally the whole community from the onset of vaccination has been the adverse effects (specifically blood clots) that may be observed after the injection of the COVID-19 vaccine. In some countries, such concerns have even resulted in the temporary or permanent discontinuation or abandonment of the application of some vaccines (especially AstraZeneca and Janssen). By evaluating rigorous studies published on this subject, the present article is aimed at identifying the association between blood clot incidence and COVID-19 vaccination. Various methods for producing the COVID-19 vaccines are analyzed, along with their possible pros and cons as well as common and rare side effects, especially VITT and blood clots. Finally, the differences of various vaccines on thrombotic events, WHO recommendations for VITT treatment, and blood clots statics are discussed.

Acute Thrombotic Events in Association With Coronavirus Disease of 2019 Immunization as Initial Presentation of Congenital Factor VII Deficiency

“…16 Multiple studies have addressed the potential risk for VTE development in association with COVID-19 vaccinations, particularly the one manufactured by AstraZeneca; however, an increased risk for thrombosis development has been more closely associated with acute COVID-19 infections. 10,11 Although an increased risk of thrombosis has not been reported with the Pfizer COVID-19 vaccine, our patient had an unidentified underlying prothrombotic risk factor-FVII deficiency. We hypothesize that the administration of a COVID-19 vaccine with a complicated postvaccination course requiring multiple PIV insertions and an underlying prothrombotic risk factor was the etiology behind this episode of acute multiple thromboses.…”

“…Reported hematologic AEs include immune thrombocytopenia, vaccine-induced thrombotic thrombocytopenia, autoimmune hemolytic anemia, Evans syndrome, aplastic anemia, antiphospholipid syndrome, catastrophic antiphospholipid syndrome, and acquired coagulation disorders 16 . Multiple studies have addressed the potential risk for VTE development in association with COVID-19 vaccinations, particularly the one manufactured by AstraZeneca; however, an increased risk for thrombosis development has been more closely associated with acute COVID-19 infections 10,11 …”

“…Although rare, when compared with COVID-19 infection-related thrombosis, cases with COVID-19 vaccine-associated thrombosis occurred in patients receiving immunizations manufactured by Moderna, Pfizer, and Oxford-AstraZeneca. 10,11 We present a case of an adolescent male who was diagnosed with FVII deficiency after developing an acute upper extremity deep venous thrombosis (DVT) and bilateral upper extremity superficial venous thromboses associated with multiple peripheral intravenous (PIV) line insertions and shortly after his second Pfizer COVID-19 vaccination dose.…”

COVID-19 Vaccine-Associated Immune Thrombosis and Thrombocytopenia (VITT): Diagnostic Discrepancies and Global Implications

“…24 Although the Sputnik V vaccine has been suggested to be a potentially potent cause of VITT, the recognized incidence may be undervalued given its lack of reporting in global literature. 25 Yet, Argentina, a large consumer of the vaccine, recently confirmed two cases of VITT after 20,538,979 doses were administered, verifying reported incidence. 24 Prevalence of VITT will differ according to the case definition and diagnostic pathway chosen.…”

Side Effects of COVID-19 Vaccines Among Diabetic Subjects and Healthy Individuals

“…This study had a few limitations. Firstly, the study didn't compare the efficacy of the COVID-19 vaccine with the natural immunity that is acquired after a COVID-19 infection, as it has been seen in many studies that natural immunity given by COVID-19 was more protective and lasts for a longer duration and without side effects of clotting [31][32][33]. Conversely, COVID-19 infection can lead to more serious complications like clotting, myocarditis, myocardial infarction, stroke, etc, and on the other hand, adverse side effects (like clotting and stroke) of COVID-19 vaccination remains extremely rare, signifying the protective role of COVID vaccination.…”