Covid-19 Related Article Summary and Critique

Subject: Epidemiology
Pages: 3
Words: 829
Reading time:
4 min


COVID-19 has arguably been the pandemic of the century, with millions of death recorded so far and many other causalities still being reported to date since its novel emergence in China in 2019. However, efforts by scientists have gradually brought the condition under control through their identification of vaccines that are being administered currently to provide the desired protection to every individual. One such vaccine is the Oxford-AstraZeneca coronavirus virus. However, some of its recipients have shown a rare and mysterious blood-clotting disorder which has led to researchers having to uncover the relationship between its inoculation and the unusual. Heidi Ledford, in his article “How Could a COVID Vaccine Cause Blood Clots? Scientists Race to Investigate,” published in Nature on the 9th of April 2021, discusses this issue through the view of the results announced by the European Medicines Agency (EMA).


Ledford introduces the article by identifying the central issue and acknowledges the possibility of a link between the vaccine and blood clots. He goes on to acknowledge that the occurrence is an unusual one even though the risk of mortality from these side effects compared to COVID-19 is relatively low (Ledford). Ledford describes the issue as a medical mystery. Additionally, Sabine Eichinger, a scientific hematologist, is acknowledged for being among the first people to identify the strange occurrence (Ledford). According to her, this occurrence is similar to what she noted in certain patients’ treatment with the blood-thinning drug heparin. The syndrome is known as heparin-induced thrombocytopenia (HIT), which bears the same features as those inoculated with the Oxford-AstraZeneca vaccine even though they had not received heparin.

Furthermore, Ledford notes that there are claims hypothesizing that the syndrome affects women more than men, especially those before sixty years, even though the study by EMA disputes this. He also reports on Behnood Bikdeli’s views, who believes that researchers should collect more data on the incidence and prevalence of the condition in unvaccinated populations since the rate of occurrence is somewhat low. This could potentially lead to increased reporting rates between the vaccine and the syndrome between those who have been vaccinated and those who have not, which could potentially lead to falsified inflation of the syndrome (Ledford). The article is concluded by van Gorp’s views who believes that the activity will lead to increased attention to the relationship between blood coagulation and the immune system.

Scientific Explanation

This article looks at the science linking the vaccination with chAdOx1 nCov-19 and the development of thrombotic thrombocytopenia. The occurrence clinically resembles heparin-induced thrombocytopenia, which is a known disorder that arises from antibody activation by platelets (Greinacher et al.). Even though those depicting this syndrome were not inoculated with heparin, recent studies have identified similar cases on serologic and clinical grounds. Nonetheless, in the case of the vaccine, the condition arises from the strong reactivity between the serum and PF4-heparin ELISA though this is believed to be an in vitro artifact (Schultz et al.). Moreover, it is highly unlikely that the quantity of adenovirus in a 500-microliter injection would lead to the activation seen in the patients (Greinacher et al.). However, the trigger likely arises from the vaccine’s free DNA due to the multimolecular complexes formed by RNA and DNA with PF4.

Article Critique

Heidi Ledford’s article is a timely one, and he presents the case as it is in the primary source. Through and through, he acknowledges the opinions of other scientists who help to build a case on the significance of the blood clots. This helps to provide credibility and reliability to his opinion and builds on information on this rare occurrence. Moreover, Ledford organizes the article into three sections talking about the location of the syndrome, the risk factors, and the causes which make it easy to follow through. However, he omits a lot of scientific detail, like information on what actually causes the reaction (Greinacher et al.). Moreover, the author avoids the use of scientific terms, which would enhance understanding of the issues involved. Furthermore, he does not evaluate the statistics provided in the primary source, which would help establish the facts of the issues under study. In this regard, Ledford should have included a table that summarizes these results to enhance this and improve the quality of his paper.

Article Evaluation

Despite the author omitting certain sophisticated scientific terms in his discussion, this helps boost the number of people who can comfortably access and understand the facts provided by Ledford. The terms used are relatively simple, and the rather complex ones are explained in detail. Thus, the article appeals to both a scientific and non-scientific audience and is likely to create more awareness of the issue. In this regard, individuals who have been inoculated with the vaccine are likely to be on the lookout for any symptoms of heparin-induced thrombocytopenia. Similarly, scientists and researchers can understand the given conditions that they may face from those inoculated with the vaccine and how to go about the treatment.

Works Cited

Greinacher, Andreas et al. “Thrombotic Thrombocytopenia after Chadox1 Ncov-19 Vaccination”. New England Journal of Medicine, 2021. Massachusetts Medical Society, doi:10.1056/nejmoa2104840.

Ledford, Heidi. “How Could A COVID Vaccine Cause Blood Clots? Scientists Race To Investigate”. Nature, vol 592, no. 7854, 2021, pp. 334-335. Springer Science and Business Media LLC, doi:10.1038/d41586-021-00940-0.

Schultz, Nina H. et al. “Thrombosis and Thrombocytopenia after Chadox1 Ncov-19 Vaccination”. New England Journal of Medicine, 2021. Massachusetts Medical Society, doi:10.1056/nejmoa2104882.