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Vaccine adverse side effects: how do COVID-19 vaccines compare?

Vaccine adverse side effects: how do COVID-19 vaccines compare?

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A database to report your vaccine impact concerns

This article is based on the information that is reported in a publicly available database compiled by the US Center of Disease Control and Prevention (CDC), termed the Vaccination Adverse Events Reporting System.

This VAERS database was set up approximately 30 years ago to allow anyone to report any side effect (whether adverse or non-adverse) suspected to be from taking a vaccination. The idea of the database is to be able to capture any worrisome events and allow rapid investigations of vaccine safety.

However, and this is very important, these reports can be submitted by anyone, and they are not investigated by CDC for accuracy. In fact, the site clearly states that “Submitting a report to VAERS does not mean that healthcare personnel or the vaccine caused or contributed to the adverse event (possible side effect).”

The point is that the information captured in this database does not at all necessarily represent the real-world incidence and how dangerous or safe vaccines might be. Rather, and we find this still to be very interesting and valuable, it represents the public’s perception of a vaccine’s safety or danger. So while the data might not be accurate in terms of what vaccines really do to people, it is still interesting to look at this data to see how people react to different vaccines in terms of reporting, including the novel mRNA COVID-19 vaccines and we wanted to show you this data in this post. Therefore do not look at this information for certainty in terms of how toxic vaccines could be, but more how toxic vaccines are perceived to be, whether that is true or not. This might not even be the perception as many doctors are extremely cautious in diligently filing reports to ensure public safety.

Nevertheless, viewing this data in such a context is still fascinating, which is the focus of this blog post.

Recently the VAERS database has seen some scientific investigation of its data to see what can be learned from such an enormous amount of compiled information. For example, a 2019 publication pointed to certain relationships between the vaccines and the reported symptoms. This research showed that symptoms (both adverse and non-adverse) that are observed frequently are positively correlated to all reported vaccines. This means that the most common symptoms observed are typical across all vaccines. On the other hand, the rare symptoms do not show such positive correction. This means that more rare observations are usually specific to particular vaccines. Focusing specifically on adverse symptoms, the most frequently reported adverse symptoms are mostly uncorrelated or negatively correlated for different bacterial vaccines. This would indicate that bacterial vaccines produce variable and potentially vaccine-specific adverse symptoms. However, the opposite is true for viral vaccines, where in many cases the reported adverse symptoms were positively correlated under different viral vaccines, especially under flu vaccines. This means that viral vaccines produce a more predictable pattern of adverse symptoms that are being reported. However, keep in mind that due to the nature of how this information is populated in the VAERS database, it is quite challenging to study any statistical relationships and the authors mentioned these special challenges.

We hope we have got your curiosity going enough to now check out what this database has shown so far for the different vaccines, and especially how that might compare to the new mRNA COVID-19 vaccines. The results are definitely captivating.

Overall, in the span of the 30 years of database, as of first week of March 2021, nearly 730,000 specific observations have been reported across what appears to be 93 different vaccines. These observations include symptoms or events (such as name of test needed, or even a lack of symptom). Basically, if it is noted in a report, it ends up in the VAERS catalogue. And we mean anything! Just look at some of the most bizarre ones that are now part of this database!

Picture of weird reported vaccine symptoms

Overall, these 730,000 observations have been noted more than 2.5 million times. Unfortunately, the number of reported patients does not appear available but it would clearly be far below 2.5 million as each patient is likely to report numerous symptoms.

With that in mind, let’s dive in!


What are the most commonly reported vaccine symptoms?

The good news is that the most frequently reported observations linked to all of the vaccines are symptoms that are typically expected as a potential reaction to vaccine. Even reporting of no adverse events ranks in the top three noted observations, and we should expect that this is likely to be underreported in a database made to report symptoms. The top fifteen observations together account for one-third of all recorded observations. However, these refer to the most observed symptoms of all symptoms, not the most observed symptoms in all patients. This is an important distinction to understand in how this data is presented. For example, fever is the most commonly reported symptom, but each patient could have numerous symptoms, which means fever could have been actually observed even more often if it was measured in group of people and not in a group of symptoms.

Blog Picture of VAERS most reported symptoms

One of the “symptoms”, death, which we will discuss in detail in this post, accounts for 0.38% of all observations, with 3006 reported (unconfirmed) deaths across all vaccines in last 30 years! So, an extremely infrequent event, not to mention again, that these are not confirmed, only stated suspected assumptions that vaccines may have caused the deaths.


Which are the most serious of reported vaccine side effects?

The VAERS database allows for categorization of these observations based on whether the patients were deemed to be in a life-threatening condition, required an emergency room visit, hospitalization or resulted in permanent disability. Let us consider these symptoms as belonging to the most common side effects linked to serious outcomes. They might not be the most dangerous or serious side effects, but they are the ones most commonly listed in patients who belonged in the above mentioned categories. Let us go through these one by one.

First let’s look at the reports for patients who ended up in emergency room, as the list of most observed symptoms in this group is most similar to the top list of general symptoms mentioned above. In fact, 8 of the top 9 most observed general symptoms are also the most commonly observed symptoms reported for patients who required a visit to an emergency room presumably because of vaccination.

Blog Picture on vaccine emergency symptoms

The take home message here is that depending on the severity, the most common symptoms we have come to expect as a result of vaccination, are also the symptoms observed in those ending up in emergency. Although, this does not mean that these were the reasons necessitating the emergency visit. We simply cannot know from looking at this data as such. The only two new symptoms that emerge in this group are vomiting and difficulty breathing. Thus, emergency visit patients do not seem to have a very different pattern of top symptoms than what are generally observed.

In terms of the most observed symptoms of all symptoms in patients that were hospitalized presumably due to vaccination, a very different picture of symptoms does emerge. Once again, fever is the most commonly observed symptom of all possible symptoms, dominating in presentation among hospitalized patients. Vomiting and difficulty breathing now occupy the top of list, and several new symptoms emerge. This includes convulsions, feeling weak/lethargic, numbness or feeling of abnormal sensations in a body part or a limb, diarrhoea, and Guillain-Barre syndrome. This last one is a serious, rare condition where your nerve cells are attacked by the immune system. It can start with a tingling sensation and lead to paralysis. Most affected people require hospitalization, as it can lead to death.

Blog Picture on vaccination hospitalization symptoms

Another symptom observed is shingles, which is a break out of skin lesions due to a previous infection by a normally dormant virus already present in a patient, and which could perhaps be attributed due to weakened immune system.

Next, let’s look at the reports for patients whose situation was deemed life threatening. Most of the symptoms are now similar to those in patients needing hospitalization with just a different order of what are the most frequently reported events. Fever was once again the most commonly observed symptom (of all reported symptoms in such patients), and as you probably can conclude by now, we will see this over and over again. Difficulty breathing is now the second most reported observation, and obstruction of airways is indeed a life-threatening situation. In third, vomiting which in excess can lead to severe dehydration which is dangerous. The unusual Guillain-Barre syndrome is now the fourth most observed symptom. Two new observations are fatigue and intensive care need.

Blog Picture on vaccine life threatening symptoms

For those patients who ended up with permanent disability, once again the list of most common symptoms is similar but with a different order of which symptoms are most often seen, and with few new symptoms showing up in the top fifteen. For those patients presumed to have become disabled due to vaccination, pain is now the second most common symptom, nearly taking over the first spot typically occupied by fever. In third place of most noted symptoms in this group is now joint pain. The other two new symptoms include muscle weakness and pain.

Blog Picture on vaccine disability symptoms

Notably, being able to observe the most common symptoms in all patients as well as the more severe situations, could potentially allow us to estimate the frequency of those more extreme events. We could get a sense by looking how frequently the same symptoms are observed in these extreme events groups by comparison to general observation.

Blog Picture on vaccine emergency events as % of all symptoms

If we look at the top most commonly observed of all symptoms that are also recorded in the patients with extreme events, as you can see, emergency room visits make up a bulk of all of the reported observations. This probably makes sense as that is where the need to utilize this database by the healthcare providers should definitely kick-in in order to start monitoring any potential adverse impact of vaccines. Statistically, emergency room recorded observations make up about 30% of the reported events. Of course, this is bound to be a gross overestimate and is not going to represent the reality of what one can expect after vaccination. It just reflects the nature of how this type of data is compiled.

In comparison, the number of recorded symptoms for: hospitalized patients; those with life threatening conditions; or those resulting in disability are much lower, representing on average 6% of recorded observations (that are common to all groups), 1.5% and 2%, respectively. Once again, that is going to be an overestimation and obviously not representative of what might happen after an actual vaccination. But possibly the ratios of those who end up in emergency room and how they fare might be reflective of reality. This would mean that approximately 20% of patients who end up in emergency room due to vaccine related complications might require hospitalization, 5% of emergency room visits could end up being a life-threatening condition for those patients, and 7% could end up with some form or disability (usually apparently some form of chronic pain). But these are just simple comparisons and perhaps also overestimates. Possibly, as the situation gets worse for a patient, the likelihood of a report being filed in VAERS database increases.


Which vaccines have reported the most symptoms?

This is actually interesting information because while the reported symptoms might not actually be due to vaccines, this data shows which vaccines are perceived to be causing the most adverse events in patients. Let’s take a look.

Blog Picture on vaccines with most reported symptoms

However, keep in mind that what we do not know from this data how frequently different vaccines are administered among the American population, so this could simply reflect the fact that the most often administered vaccines will end up being reported on most frequently. A number of these are given to nearly all newborns in the US and several in later years of life where compliance can be variable. Hence it might not be surprising that the influenza vaccine is in top spot as it is administered to people on a yearly basis.

If anything, with around 2.5 million observations, in comparison to the many millions of individuals who have been vaccinated, this database could indicate how safe vaccines can be expected to be, even if these events are under-reported.

What is interesting is that the COVID-19 vaccines, which in this data included only the mRNA vaccines from Pfizer/BioNTech and Moderna (the US FDA only has just approved the Johnson&Johnson vaccine which uses a different delivery method than mRNA) has already made the top fifteen list of most reported observations despite only two months of reporting. At the start of December 2020 it was not even on the list yet. This could be for number of reasons though. One is that we are undergoing the fastest vaccination program in history, and the US is one of the world leaders in terms of vaccinating its citizens with COVID-19 vaccines, resulting in millions of people vaccinated in an extremely short time frame. Another reason is that these mRNA vaccines are completely novel, never having been tried before on humans, and as a result are under extra scrutiny and vigilance of observation from healthcare providers keen to ensure public safety. As a result, more symptoms could be reported in an overabundance of caution then normally would take place. But as of this moment, the use of these COVID-19 vaccines has resulted in more than 31 thousand observations being reported.


What are the most common symptoms reported for COVID-19 vaccines?

Before moving forward, keep in mind that we actually do not know if this information is accurate as it has not been verified. Nearly all of the symptoms are already seen in the above context. We decided to extend the number of presented symptoms because, provocatively, already in 21st place, is the reported event of death with these new COVID-19 mRNA vaccines . We will dig deeper into it in a moment, but this is certainly extremely unusual for death to present as one of the top symptoms. In contrast, for all vaccines combined, death is the 136th reported symptom. A huge discrepancy.

Blog Picture on COVID19 vaccines symptoms

As you can see, COVID-19 vaccines produce their own pattern of more frequently observed events, with fever finally dislodged from first place by headache. That is probably a welcome exchange. The one new observation that will stand out is testing positive after vaccination with observation rate of just over 4% (again, this is likely to be a high overestimate as such events could be prompting health providers to file such a report). Actually, it is not that unusual to test positive after a vaccination for couple reasons.

First, the immunity against SARS-CoV-2 takes time and is not expected to kick in effectively within the first couple of weeks or so. If anyone gets infected within that short window of vulnerability after the first dose of vaccine, they very well could test positive. This is important to know so that safety precautions are not thrown out the window the moment you get a jab.

Another reason is that vaccination is not an automatic panacea of protection against SARS-CoV-2. Just like your genetics is a random deck of cards dealt to you, so is your body’s ability to mount an immune response against the virus as a consequence of vaccination. Not all of these responses will be equal. Some people will build an amazing response while others will not. Some antibodies will be produced as a consequence of vaccination (or natural infection) and will be binding the SARS-CoV-2 virus spike protein just perfectly, and it will wipe out the virus. Some antibodies will not be as efficient. Some antibodies may even work against you and can increase your subsequent likelihood of infection (luckily the odds of this are small). The point is, biology is semi-random, as will be your reaction to a vaccine and your subsequent ability to fight off an infection. For some people who get vaccinated, that will still not be good enough. Where the real impact takes place is on a population-wide scale. The more people that do build immunity, either through prior SARS-CoV-2 infection, or through vaccination, the more difficult it will be for the virus to effectively spread through the population. You might have heard the estimated number of the population needed to achieve herd immunity being around 70% or so. The reality born out of observation from historical vaccinations that eliminate presence of the diseases is that perhaps that number will have to be well into the 90s. This is why the vaccination program is going on at such a breakneck speed, to reach that herd immunity as rapidly as possible.

And the final reason why a person might still test positive after vaccination is because of new strains of virus. These vaccines were generated and approved prior to emergence of new SARS-CoV-2 strains and their effectiveness against these strains does not appear to be as good as prior strains. The new strains appear to harbour mutations to help them evade some of the immune systems antibodies.

This is simply the reality of attempting to fight a virus. It takes a lot of effort.

If you are curious how the two mRNA vaccine makers stack against one another, they are almost tied for number of reported symptoms each, with Moderna vaccine accounting for 43% of reported observations and Pfizer/BioNTech vaccine contributing 57% of the observations. Here is how they compare.

Blog Picture on Moderna vs Pfizer vaccine symptoms

As you can see both vaccines are fairly similar in terms of their potential symptoms effect. Three things that jump out is that Moderna is causing more issues related to injection site discomfort but potentially could be more rapid in protection against SARS-CoV-2 infection (reflected in the lower rate of observed positive tests after vaccination).


Why do COVID-19 vaccines report such high death rate?

This of course is the question in the context of knowing that these are not verified reports, and therefore the stats might be inaccurate, but still why is the death rate so much higher with COVID-19 vaccines than ever reported in the past for all vaccines in the last 30 years? To give you some further context, in those last 30 years, death has been reported to VAERS database just over 3,000 times. With COVID-19 vaccines reported death count of 1,161, it accounts for almost 40% of reported deaths ever registered in the database!

For the historical reporting, you can see what this looks like in the graph below. See that spike in 2021? That spike is all due to COVID-19 vaccines! So, what gives?

Blog Picture on vaccine deaths history

First of all, many people have already commented on this observation, leading to rumours that COVID-19 vaccines are dangerous. One fact-checking report from Reuters commented on the misuse of COVID-19 VAERS data. What that article mentioned is that all reported deaths are investigated by CDC. This sounds great as Merogenomics has also already commented on this in its videos dedicated to mRNA vaccines, as to when is this going to be investigated. If indeed this has already been scrutinized then we would like to see a report from the CDC detailing their investigation so as to alleviate the public’s concern which is already strained on account of these vaccines being so novel, produced and tested so fast, and potentially becoming mandatory to allow normal function in a society. If such report already exists, let us know.

Without an official explanation from CDC, one possible explanation for this spike linked to COVID-19 could be due to the age demographics and these new mRNA vaccines were first and foremost used to target the members of our society that are most vulnerable to infections and serious consequences of SARS-CoV-2, namely healthcare workers and the elderly, respectively. Old people are obviously more likely to die from any number of causes, and these natural events continue unabated whether an old person is vaccinated or not. However, if an old person who was just vaccinated dies suddenly, this still might alert the family or treating physician that potentially the vaccine might have contributed to that death, resulting in a report being filed in VAERS database, even if it is due to completely unrelated cause.

Indeed, there may be support for this notion. If you look at the age breakdown, you will see two groups that stand out. The largest bulk of reported deaths is in the age bracket of 65 or older. The vast majority of this is currently linked to COVID-19 vaccine deaths. The second largest group is toddlers, and then deaths are evenly distributed across all ages. That is attributable to all other vaccines reported in last 30 years. And if we look at the age breakdown for COVID-19 deaths, almost 80% of them are linked to those considered 65 years or older.

Blog Picture on vaccine deaths age range

Blog Picture on COVID vaccine deaths age

Therefore, it is very feasible that most and perhaps all of the COVID-19 deaths are natural events that simply happened to coincide with vaccination. Previously, all of the deaths reported to VAERS database had been analyzed in detail which would account for almost all of the deaths observed prior to the recent spike observed with COVID-19 vaccines. That report clearly concluded that based on medical and autopsy records, all of the deaths are what is expected based on what is observed in a population in same age groups. The point is, death from vaccine is nearly unheard of, and likely this is also a reflection of natural events unrelated to vaccination.

If we could know the actual number of how many people have been reported on for the 65 and older age group of those vaccinated with COVID-19 vaccines, we could compare that reported death rate to the expected mortality rate for elderly. We thought by perhaps looking at the most commonly reported symptom, we could see what the minimum number of people in this group is, and see how many of those we would expect to die of natural causes unrelated to vaccine. Unfortunately, we could not do that.

Blog Picture on Elderly COVID19 vaccine symptoms

The most reported symptom in the elderly age group after COVID-19 vaccination is death itself. Again, this is apparently being investigated by CDC and no public warning has been issued as far as we know, so this is all expected to be unrelated, so these observations are then possibly due to concerned, observant doctors doing their job thoroughly. It is actually good to see that this database is being used correctly to provide information to ensure proper investigations and maintain public safety.

Another way to see if the observed deaths linked to COVID-19 are actually due to natural causes is to see what are the most commonly seen symptoms in such patients who died, and how they compare against all those vaccinated with COVID-19 vaccine. Did the patients who died also exhibit the same symptoms that were observed in all vaccinated patients? Or perhaps more frequently, which could suggest patients who died were especially burdened with symptoms that might have contributed to their death. Let’s take a look.

Blog Picture1 on symptoms of dead after COVID19 vaccine

If deaths were strictly coincidental, natural events in those who took the COVID-19 vaccines, then a potential supporting pattern of this would be to see such patients exhibit symptoms at least in same frequency as rest of the vaccinated patients or lower. If symptoms are seen with the same frequency, it could show that death is just random as same rate is seen in those who died as well as those who did not. If a lower rate of symptoms is seen, it could indicate that death took place randomly even before any symptoms took place. We could then expect this to potentially be similar to the pattern typically observed in people 65 and older who took any vaccine. If we were to see much higher symptoms on the other hand, that could suggest that the symptoms were a contributing factor to death.

With those who died after the COVID-19 vaccine, an interesting pattern of symptoms emerge. The first three symptoms in the top four most observed symptoms we have not yet discussed, and included being unresponsive, needing resuscitation and suffering a heart attack. These might not be surprising as these are people who ended up dying, and we instantly learn that approximately a tenth of these patients happened to have had a heart attack, a very common cause of death. Difficulty breathing was the second most observed symptom, even more so than typically seen in those taking a COVID-19 vaccine, and this too might be expected, as obstruction of airways can easily be fatal, although what would have been the cause behind that? An event such as an anaphylactic reaction? But it could also be linked to respiratory issues which are also a common cause of death in the elderly. This event is actually rare in all other elderly groups in these reports which could indicate that this could be a dangerous side effect in the elderly to watch out for in those being vaccinated with COVID-19. But only if these deaths were to be confirmed to be linked to a vaccination due to a breathing obstruction from allergic reaction. Without that confirmation, it is just useless information.

We can see that those who died after a COVID-19 vaccination, also tested more frequently for SARS-CoV-2 virus and ended up with the COVID-19 disease than the rest of the patients vaccinated with same vaccines. Thus, a portion of those patients might have simply died of COVID-19 – the vaccine simply did not help them if they got infected too soon or were already infected. Then we have the remainder of the symptoms that we have already seen in the top 20 symptoms after COVID-19 vaccinations: fever, fatigue, weakness and vomiting. All of these are indeed similar rates in those who died after being vaccinated or lower than the rates observed in the entire COVID-19 vaccinated group. This could indicate random death as opposed to death due to overpowering symptoms resulting from vaccination and contributing to death. In the remainder of the elderly these same symptoms are even more rare.

What is interesting though is that if we look at the top symptoms again, unresponsiveness, resuscitation and heart attacks, these are almost exclusively observed only in those who were vaccinated for COVID-19, with most of these symptoms only seen in those who died after taking this vaccine. In the remainder of all of the elderly who have taken any vaccine over the years and have been reported, these events are almost never reported! It is interesting that this connection between these symptoms has never been previously reported on by overzealous doctors for any other elderly person who might have experienced these events by chance after being vaccinated.

It is such small patterns that are the reason why having a detailed report from the CDC after investigating all of these deaths would be handy. Right now, it could appear that COVID-19 vaccines disproportionately exhibit some heart attack aftermath compared to all other 92 vaccines in the same age group of patients.

But the far more likely explanation is that this observation is due to an abundance of current reporting of very cautious doctors due to the novelty of these mRNA vaccines. And we actually do want to see that because after all, that is the reason why this database was created, and doctors reporting to this database are primarily trying to protect the well-being of the public.

We will keep updating you on this topic through our Merogenomics YouTube channel (and check out our latest video on mRNA vaccines outcomes), so stay tuned! mRNA vaccines are a topic of great interest to us!


This article has been produced by Merogenomics Inc. and edited by Jason Chouinard, B.Sc. Reproduction and reuse of any portion of this content requires Merogenomics Inc. permission and source acknowledgment. It is your responsibility to obtain additional permissions from the third party owners that might be cited by Merogenomics Inc. Merogenomics Inc. disclaims any responsibility for any use you make of content owned by third parties without their permission.


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