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Many people are concerned about the possible side-effects of receiving vaccines to help prevent COVID-19 disease due to infection by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Some of my friends, extended family, patients, and health professional colleagues have expressed the view that the side-effects of various COVID-19 vaccines may actually be more hazardous and dangerous than the side-effects of actually being infected with the virus. They have cited concerns over deaths due to severe allergic reactions, deaths due to heart problems, and much else.
Therefore I conducted the following research in late December 2021 comparing the risks and health consequences in three different scenarios:
Many people are concerned about the possible side-effects of receiving vaccines to help prevent COVID-19 disease due to infection by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Some of my friends, extended family, patients, and health professional colleagues have expressed the view that the side-effects of various COVID-19 vaccines may actually be more hazardous and dangerous than the side-effects of actually being infected with the virus. They have cited concerns over deaths due to severe allergic reactions, deaths due to heart problems, and much else.
Therefore I conducted the following research in late December 2021 comparing the risks and health consequences in three different scenarios:
To understand how dangerous or deadly a virus is, I want to first clarify how one type of research calculates the results. I will do this by the following analogy. Imagine you are trying to estimate the number of deaths due to car accidents. What we you are trying to discover could be called the Motor Vehicle Incident Fatality Rate (MV IFR). Although this seems simple at first, there is one big problem: how do you find out how many car accidents have happened? After all, many people will not report a car accident that only causes a bent bumper bar or some scratched paint.
Also, in order for the MV IFR to be fairly understood, the counting must be done over a reasonable length of time. Obviously reporting the MV IFR based on only one day’s worth of data is not going to create a real world accurate estimate of what happens over a month or a year. Finally, so that all the deaths that result from car accidents are included, then it is necessary to know how many of the deaths happened not just at the time of the accident, but even after a few days of the accident. This is because some car accident victims may be rushed to a hospital after the accident, but then only survive a few more days.
In a similar fashion, to estimate the number of deaths due to individuals being infected by SARS-CoV-2, the calculated result could be called the Covid -19 Infection Fatality Rate (CV IFR). Although this seems simple at first, there is one big problem: how can anyone find out how many people have had the virus? After all, not all people who are infected with the virus will get significant symptoms, and so some will not report to a doctor and will ‘escape’ being counted. If the research only counts the number of people who actually develop symptoms then it will not generate a true picture of the CV IFR.
Fortunately there are ways to create an estimate of the actual number of people infected, and these methods result in producing both a low and a high estimate. This has been reported in 24 different published scientific articles, from a range of countries including those in the Americas, Asia and Europe. One research article examined all of these reports, which were published between February and June 2020, but included data from the beginning of the pandemic.[1] This means that the duration of time during which people were bing infected was sufficiently large. The authors estimated that the CV IFR was between 5,300 deaths per million to 6,800 deaths per million people who actually were infected with the virus. Thankfully, at this stage there have not been any large countries were all the citizens have been infected.
There is a simpler way to investigate the harm due to coronavirus. This involves discovering the proportion of deaths over time due to COVID-19 while ignoring those people who do not have symptoms or only have minor symptoms. It will therefore be a much higher rate than the CV-IFR. As this simpler rate is based on the number of people who report to a doctor that they have symptoms (and therefore create a file or a case) it is called the case fatality rate (CFR). One review article reported the CFR based on 39 published studies that reported CFRs in 2020. Many countries were included, such as: Canada, China, Italy, Japan, Singapore, South Korea, and the US. The overall pooled estimate from all these studies for the general population was 1.0%. That equates to 10,000 deaths per million people who are infected with the virus and who have reported symptoms. Alarmingly, the estimate for those who had to be admitted to hospital or intensive care units (ICUs) was 13% and 37% respectively. These figures are extremely concerning, as they are equivalent to 130,000 deaths to 370,000 deaths per million people who have been admitted to hospital or ICU respectively.
The death rate is sometimes referred to as the mortality rate, whereas the rate of sickness is called the morbidity rate. A very large study was carried out in Israel, and they expressed their findings by comparing the difference in risk between infected and non-infected people by measuring the difference in terms of the risk of adverse health events per 100,000 people.[2] I converted their figures to per million for convenience. This large study examined over 173,100 people who were infected versus those who were not infected but matched for age, sex, place of birth, socioeconomic status and other variables. Infection was most strongly associated with an elevated risk – in terms of events per million people – of:
These diagnostic categories are often serious. Myocardial infarction is death of heart muscles cells, and intracranial haemorrhage is bleeding inside the brain.
The next task was to find out how dangerous it is to receive vaccination against COVID-19. To do this, I examined a number of known side effects due to vaccination with mRNA vaccination.
One side effect of receiving a vaccine is anaphylaxis, which is a severe allergic reaction. It is important to note that anaphylaxis can happen to anyone, and is currently defined as a serious reaction with rapid onset (minutes to hours) that is potentially life-threatening. It usually readily advances and often involves the skin and oral mucosa (appearing as swelling of the lip or tongue), the gastrointestinal system, or cardiovascular system. It is a serious condition, with yearly fatality rates due to anaphylaxis in the UK being approximately 0.47 cases per million people.[3]
During a period of about 9 days in December 2020, monitoring in the US detected 21 cases of anaphylaxis after more than 1,893,300 first doses of the Pfizer‐BioNTech COVID‐19 mRNA vaccine had been given.[4] This equates to 11.1 cases per million doses. Of those people who developed anaphylaxis, 71% (21) of them developed the anaphylaxis within 15 minutes of vaccination. Of these 21 patients, 17 were treated in an emergency department, but only four were hospitalised. There were no deaths due to anaphylaxis from the vaccination.
Another side effect of receiving a COVID-19 vaccine is inflammation of the heart muscle, which is referred to a myocarditis. The inflammation can cause other tissues to be affected, such as the thin membrane that lines the outside of the heart (called the pericardium). If the heart muscle and the pericardium are inflamed it is called myopericarditis.
One study in the US examined reports of myocarditis – encompassing pericarditis and myopericarditis – that occurred within 7 days of people receiving a second dose of an mRNA vaccine.[5] They found that the rates varied according to age and sex, and ranged from:
When looking at a subgroup of 1,094 patients who had suspected myocarditis, 76% of them developed this only after their second dose of vaccine. By examining those of the 1,094 who were less than 30 years old over a six-week period in 2021, they found that only 323 of the 484 patients actually had myocarditis. The median time span in which they developed symptoms was two days (range zero to forty days). 96% (i.e 304) of the 323 were hospitalised. The most important finding from my point of view was that most individuals only had relatively mild symptoms, and of the 304 that were not only hospitalised but could be traced, 95% of them had been discharged and none of them had died at the time of the review. This is encouraging as myocarditis may cause up to 12% of deaths due to sudden cardiac arrest in young adults.[6]
A larger study based in the US examined all patients that were admitted to Accident and Emergency departments (ED) within 10 days of receiving a COVID-19 vaccination.[7] This was done during the months of December 2020 to March 2021. During these months, 1,842 patients visited the ED within 10 days of COVID‐19 vaccine administration. The average age was 70.3 years. It is important to note that these 1,842 patients may or may not have been admitted due to the vaccination itself. It may have just been coincidence. After making comparisons to an unrelated control group (as discussed in a separate paper) the authors noted several deaths.
Two patients (0.01%) who received the Pfizer BioNTech (BNT‐162b2) vaccine died. One of these died from cardiac arrest, and the other from arteriosclerosis which is colloquially called hardening of the arteries. This is compared to four patients (0.02%) in a ‘control’ group. The low figure of 0.01% equates to 100 deaths per million people vaccinated. In a very parallel manner only two patients (0.01%) who received the Moderna vaccine (mRNA‐1273) died. Once more one was from cardiac arrest, but the other died from suicide. This compared to three patients (0.02%) who died in the same ‘control’ group. It was not concluded that any of the four patients who died after being vaccinated definitely did so due to a direct or indirect (in the case of the suicide) effect from the mRNA vaccinations.
Another way of examining the negative impact of mRNA vaccine is to compare, over time, a large number of people who have been vaccinated against COVID-19 with roughly the same number of people who were unvaccinated. Such a study was done in Israel. For each unwanted health diagnosis, a comparison was made between vaccinated and non-vaccinated individuals matched according to sociodemographic and clinical variables. The sociodemographic variables included age, sex, socioeconomic status, and place of birth. The study had a follow-up period of 21 days after both the first and the second vaccine doses, so a total of 42 days follow up for each vaccinated person.
It was a massive study based in Israel (part of the same study mentioned above), with vaccinated and non-vaccinated groups each having an average of over 884,800 people. The researchers found that some diagnostic categories were more prevalent among the vaccinated compared to the unvaccinated.[8]
Vaccination was most strongly associated with an elevated risk – in terms of events per million people – of:
Importantly, there were no reports of fatalities in this large study based in Israel.
On the opposite side of the coin, the researchers also found that vaccination provided significant protection against a number of health problems, including: anaemia (a decrease in the number or red blood cells), acute kidney injury, intracranial haemorrhage (bleeding inside the head), and lymphopaenia (a decrease in the number of white blood cells called lympohocytes).
Putting it all together, the risk of dying with COVID-19 may be least 5,300 deaths per million people infected. Even more alarming is the fact that there are about 10,000 deaths per million people who are infected with the virus and have also developed symptoms (i.e. the infected people were detected by a health authority).
By contrast, it can be seen that the number of deaths related to mRNA vaccination due to a severe allergic response (such as anaphylaxis) or due to myocarditis (inflammation of the heart) appears to be less than one person per million doses of vaccine. One study presented the possibility that deaths due to cardiac arrest and arteriosclerosis related to mRNA vaccination may be approximately 100 deaths per million, but the data was not conclusive. Certainly 100 is much less than the 5,300 CV IFR and the 10,000 CFR mentioned above due to COVID-19.
A similar trend can be seen when comparing the risk of certain adverse health events between the vaccinated and the infected. The risk of having myocarditis related to COVID-19 is about 110 events per million people, whereas the risk of myocarditis related to mRNA vaccination may be between 41 and 1, depending on age and sex.
Unfortunately, not only does the SARS-CoV-2 virus cause death and myocarditis, it also causes a large number of debilitating health events, such as heart arrhythmia, pulmonary embolism, deep-vein thrombosis, myocardial infarction (that is death of hearth muscles cells), and pericarditis.
Finally, there are other unexpected benefits to the mRNA vaccines, such as a decrease in the risk of having various other serious health outcomes, such as anaemia, acute kidney injury, intracranial haemorrhage, and lymphopaenia.
I hope that this article will help persuade people who are exposed to the possibility of being infected with SARS-CoV-2 to favourably consider COVID-19 vaccination.
[1] G Meyerowitz-Katza & L Meronec, A systematic review and meta-analysis of published research data on COVID-19 infection fatality rates. International Journal of Infectious Diseases, 2020; 101: 138–148.
Published online 2020 Sep 29. doi: 10.1016/j.ijid.2020.09.1464
[2] N Boarda, N Dagan, et al., Safety of the BNT162b2 mRNA Covid-19 Vaccine in a Nationwide Setting. New England Journal of Medicine, 2021 Aug 25 : NEJMoa2110475, Published online 2021 Aug 25. doi: 10.1056/NEJMoa2110475
[3] PJ Turner, MH Gowland et al., Increase in anaphylaxis-related hospitalizations but no increase in fatalities: an analysis of United Kingdom national anaphylaxis data, 1992-2012. J Allergy Clin Immunol. 2015 Apr;135(4):956-963.e1. doi: 10.1016/j.jaci.2014.10.021.Epub 2014 Nov 25.
[4] CDC COVID-19 Response Team and Food and Drug Administration, Allergic reactions including anaphylaxis after receipt of the first dose of Pfizer‐BioNTech COVID‐19 vaccine — United States, December 14–23, 2020. Am J Transplant. 2021 Mar; 21(3): 1332–1337. Published online 2021 Feb 28. doi: 10.1111/ajt.16516. See also: M Sokolowska, T Eiwegger et al., EAACI statement on the diagnosis, management and prevention of severe allergic reactions to COVID‐19 vaccines. Allergy, 2021 Jan 16 : 10.1111/all.14739. doi: 10.1111/all.14739 [Epub ahead of print]
[5] JW Gargano, M Wallace, et al., Use of mRNA COVID-19 Vaccine After Reports of Myocarditis Among Vaccine Recipients: Update from the Advisory Committee on Immunization Practices — United States, June 2021. MMWR Morb Mortal Wkly Rep. 2021 Jul 9; 70(27): 977–982. Published online 2021 Jul 9. doi: 10.15585/mmwr.mm7027e2
[6] Myocarditis Foundation, https://www.myocarditisfoundation.org/wp-content/uploads/MyocarditisAndSuddenDeath.pdf. Accessed 20/12/2021
[7] T Kewan, M Flores et al., Characteristics and outcomes of adverse events after COVID‐19 vaccination. J Am Coll Emerg Physicians Open. 2021 Oct; 2(5): e12565. Published online 2021 Oct 13. doi: 10.1002/emp2.12565
[8] N Boarda, N Dagan, et al., Safety of the BNT162b2 mRNA Covid-19 Vaccine in a Nationwide Setting. New England Journal of Medicine, 2021 Aug 25 : NEJMoa2110475, Published online 2021 Aug 25. doi: 10.1056/NEJMoa2110475.
A brief introductory review of the medical literature on the subject of the safety of the COVID-19 vaccines.
