Risk of thrombocytopenia and thromboembolism after covid-19 vaccination and SARS-CoV-2 positive testing: self-controlled case series study
BMJ 2021; 374 doi: https://doi.org/10.1136/bmj.n1931 (Published 27 August 2021) Cite this as: BMJ 2021;374:n1931Linked Editorial
Strengthening international surveillance of vaccine safety
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Dear Editor,
basis for this article is that the risks associated with the vaccination need to be compared against the risks of covid-19 itself. Even though the article provides very interesting and important results, it does not provide a proper comparison of vaccination risks with covid-19 risks.
This study does not have a random sample of people infected with covid-19. This study is based on people that were tested positive, and people with complications are much more likely to be tested than people without complications.
Therefore, the risks of covid-19 reported in this article do not apply for a general population. The true risks associated with covid-19 are lower (probably significantly lower) than the numbers reported in this article.
Competing interests: No competing interests
Dear Editor
We really must face the ethical problem here that people will die or be seriously maimed who would otherwise have been healthy [1]. At the moment people are being urged to self-sacrifice when they are at little personal risk and where the intervention might even mask their symptoms (should they develop the disease) putting others at risk, and where vaccine induced herd immunity looks no more than a chimera.
The problem here is the morality of the system rather than the people who make the sacrifices convinced that they are benefitting the nation or the community. I do not believe it is alright for public health officials - not to mention mainstream journalists and politicians - to pat the injured and bereaved on the head when they should have found better interventions [2]. Both Michael Ford and Imran Usmani make excellent points [3,4]. Please can we call this wretched Battle of Britain off: it is simply not appropriate.
[1] Hippisley -Cox et al, ‘ Risk of thrombocytopenia and thromboembolism after covid-19 vaccination and SARS-CoV-2 positive testing: self-controlled case series study’, BMJ 2021; 374 doi: https://doi.org/10.1136/bmj.n1931 (Published 27 August 2021)
[2] Noel Thomas, ‘ Matt Morgan: Caring for unvaccinated patients’, 26 August 2021, https://www.bmj.com/content/374/bmj.n2022/rr-2
[3] Michael Ashley Ford, ‘Re: Risk of thrombocytopenia and thromboembolism after covid-19 vaccination and SARS-CoV-2 positive testing: self-controlled case series study’, 27 August 2021, https://www.bmj.com/content/374/bmj.n1931/rr-0
[4] Imran M Usmani, ‘ Re: Risk of thrombocytopenia and thromboembolism after covid-19 vaccination and SARS-CoV-2 positive testing: self-controlled case series study’, 27 August 2021, https://www.bmj.com/content/374/bmj.n1931/rr
Competing interests: AgeofAutism.com, an on-line daily journal, concerns itself with the potential environmental sources for the proliferation of autism, neurological impairment, immune dysfunction and chronic disease. I receive no payment as UK Editor. I also moderate comments for the on-line journal ‘The Defender’ for which I am paid. I am also a member of the UK Medical Freedom Alliance
Dear Editors
One swallow does not a summer make; this study may not be the only research investigating risks of complications related to COVID-19 vaccines side by side with COVID-19 itself, but certainly it may be an important bellwether of findings of future studies in this matter.
Some opponents of vaccination (in general) and those who have COVID-19 vaccine hesitancy may take advantage of these numbers to justify their views, but I have (uncharacteristically) only one comment in response to the findings here:
Astra Zeneca sure needed better media communication specialists, marketing experts and public relations strategists than what they have so far, considering the discrepancy in public concerns and brand damage in response to vaccine-related adverse events connected to ChAdOx1 nCoV-19 when compared to those of “the other vaccine”.
Competing interests: No competing interests
Dear Editor
Following the coroner's ruling in the death of 44 year old Lisa Shaw, I think it is important to perform a risk/benefit analysis of vaccination in those aged under 50. This article has not addressed the question of whether the benefit of vaccination outweighs the risk in those under 50, especially those like Lisa Shaw who have no underlying health conditions.
The articles concludes that the risk of haematological complications from Covid-19 vaccination is about 1 in 55,000. Crucially, the risk appears to be same in those under 50 compared to those over 50. Vaccination is therefore justified in people in whom the risk of serious complications from SARS Cov-2 infection is greater than 1 in 55,000. Clearly the risk of SARS Cov-2 infection is much higher than this in those aged over 50, but it is probably lower than this in teenagers and adolescents. In middle aged people with no underlying health conditions the risk/benefit ratio may be marginal.
It should also be noted that the risk of complications reported in this article for those with SARS Cov-2 infection was calculated using national data, and it is therefore the case-complication ratio rather than the infection-complication ratio. The infection complication-ratio is probably much lower as it would include the large number of asymptomatic or mild infections that are not captured in the national data.
Imran Usmani
Competing interests: No competing interests
Dear Editor,
The title of this paper is grossly misleading. The analysis was completed only on short-term data, and only for those whose primary outcomes were hospital admission or death, and only using an incredibly small risk period of just 8-28 days. The obvious limitations of this review are in no way implied by the title and as this paper is being referred to by news outlets to promote vaccine safety, the paper title requires a better reflection of those limitations. An accurate study of the risk of thrombocytopenia and thromboembolism after covid-19 vaccination can only be performed by studying a substantial number of blood samples over a prolonged period of time.
Competing interests: No competing interests
Re: Risk of thrombocytopenia and thromboembolism after covid-19 vaccination and SARS-CoV-2 positive testing: self-controlled case series study
Dear Editor
As I understand it, all the patients in this study who tested positive for Covid were also vaccinated. It is therefore not a comparison between side effects for those who had been vaccinated and those who had tested positive for SARS-CoV-2 but were not vaccinated. This is therefore not a valid comparison of the effects of vaccine vs the effects of infection.
yours sincerely
Hugh Osmond
Competing interests: No competing interests