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Facts and Myths about the COVID-19 Vaccination

Feb 09, 2021
As an Allergist & Immunologist, I was recently asked to write a paper about the “Myths of the COVID-19 vaccination.”

As an Allergist & Immunologist, I was recently asked to write a paper about the “Myths of the COVID-19 vaccination.” Therefore, the end of this article contains some of the more common ideas patients have presented to myself or my colleagues with my response. As a physician and having performed research myself, it seemed imperative that facts were also presented. Many patients are justifiably concerned about the newness and novelty of this vaccination, as am I. There is, after all, limited safety data is available. However, an incredible investment in thought and expense has been made to deliver vaccines that are effective and deemed safe as rapidly as possible for the greater good. Hopefully this will answer most of your questions. To answer your first question, yes I have received both vaccinations (of the Pfizer-BioNTech vaccine).

How does the COVID-19 vaccination work?

The two mRNA vaccines currently available, produced by Pfizer-BioNTech and Moderna, contain mRNA, synthetically produced in a lab, surrounded by an oily coat of lipid nanoparticles. When injected, the lipid coat protects the fragile vaccine from chemicals, enzymes, and cells in our blood by which it would normally be potentially destroyed during a real infection. This coat fuses with the cells of our body that it bumps into, allowing entry of the mRNA. The mRNA only makes the proteins of the Coronavirus outer coat, which is what it uses to fuse with our cells during a real infection. These outer coat proteins then take their position on the outside of our cells which enables our immune system to recognize and target them for destruction. When these cells die, more of the outer coat protein is released, increasing and recruiting other immune system responses.

How effective are the vaccines?

Both available vaccines are 95% effective. The Pfizer-BioNTech vaccine is given in 2 doses 21 days apart. The Moderna vaccine is given in 2 doses that are given 28 days apart. Importantly, in the course of the Pfizer-BioNTech study, “No Covid-19-associated deaths were observed.” (Polack, FP, et al. Safety and Efficacy of the BNT162b2 mRNA Covid-19 VaccineN Eng J Med 2020; 383: 2603-15).

How many people were studied in the trials?

44,000 people participated in the Pfizer-BioNTech vaccine trial ( and 30,400 people participated in the Moderna trial (

What is the vaccine distribution to date?

At least 12,279,180 persons in the United States and 33.46 million persons world-wide have received at least one vaccination (updated 1/15/21 and 1/14/21, respectively); 2.21 million persons or .03% of the world is vaccinated as of 1/14/21 and 1.61 million persons or 0.49% of the United States are vaccinated as of 1/15/21 (

What are the ingredients of the vaccines?

Pfizer-BioNTech lists the following ingredients of its vaccine as (

Messenger Ribonucleic acid (mRNA) encoding the SARS-CoV-2 spike; 4-hydroxybutyl)azanediyl)bis(hexane-6,1-diyl)bis(2- hexyldecanoate), 2-[(polyethylene glycol)-2000]-N,N-ditetradecylacetamide, 1,2-distearoyl-sn-glycero-3-phosphocholine, cholesterol, chloride, monobasic potassium phosphate, sodium chloride, dibasic sodium phosphate dehydrate, and sucrose.

The ingredients of the Moderna vaccine ( are listed as:

mRNA encoding the SARS-CoV-2 spike, SM-102, polyethylene glycol [ PEG] 2000 dimyristoyl glycerol [DMG], cholesterol, 1,2-distearoyl-sn-glycero-3-phosphocholine [DSPC], tromethamine, tromethamine hydrochloride, acetic acid, sodium acetate, and sucrose

What are the adverse events related to the vaccine that occurred in the trials?

Side effects recorded in the Pfizer-BioNTech ( and Moderna ( trials included local reactions such as pain, swelling and redness at the injection site as well as systemic effects of fatigue, headache, myalgias and joint pain, lymphadenopathy (lymph node enlargement), vomiting, diarrhea, chills and fever. The likelihood of any such reaction was high but most cases were mild to moderate and transient. These immediate and non-life-threatening but uncomfortable side effects are due to the “reactogenicity” of a vaccine and are cause by the immune system response that it generates.

While mild side effects were very common, severe symptoms were not (Polack, FP, et al. Safety and Efficacy of the BNT162b2 mRNA Covid-19 VaccineN Eng J Med 2020; 383: 2603-15; These included work and activity-limiting “reactogenicity” (

In the 2 months following vaccination, there were 4 additional severe adverse events that occurred in the Pfizer-BioNTech trial: a shoulder injury related to vaccine administration, a right axillary lymphadenopathy, a paroxysmal ventricular arrythmia, and a right leg paresthesia and of these the FDA’s ruled that only the shoulder injury and the lymphadenopathy were thought to be related to the vaccine ( In the group followed for 2 more months, there were 12 cases of appendicitis, 8 in the vaccine group and 4 in the placebo group. “None of the cases were assessed as related to study intervention by the investigators (” There were 4 cases of Bell’s palsy in the vaccine group and none in the control group for a rate of .0091%. The FDA indicated that the number of cases in the “vaccine group do not represent a frequency above that expected in the general population (”

Pfizer-BioNTech concluded that after either dose, “no participant reported an immediate allergic reaction to vaccine (” One participant had angioedema (swelling) of both eyes on day 13 after dose 1 and one had an allergic reaction (no further information available) in the vaccine group and one participant of the placebo group had a reaction to oral penicillin ( The FDA conducted a separate analysis and determined that 0.63% of subjects in the vaccinated group v. 0.51% in the placebo group may have had adverse events potentially representing allergic reactions (

For the Moderna trial, several cases of lip swelling occurred that the FDA supposed were “possible the localized swelling in these cases is due to an inflammatory reaction from interaction between the immune response after vaccination and the dermal filler (” As well, The FDA’s opinion was that 3 of the reported severe adverse events were likely related to vaccination, one report of intractable nausea/vomiting and 2 reports of facial swelling. There was also reported exacerbation of some conditions. About this the FDA indicated that “the possibility that the vaccine contributed to the SAE reports of rheumatoid arthritis, peripheral edema/dyspnea with exertion, and autonomic dysfunction cannot be excluded (” As of December 20, 2020, there have been three reports of Bell’s palsy in the vaccine group and one in the placebo group ( for a rate of .0099%. The “FDA’s assessment [indicated that] a causal relationship cannot be definitively excluded.” The rate of hypersensitivity reactions was reported as 1.5% for the vaccine and 1.1% for placebo with no anaphylactic or severe hypersensitivity reactions occurring in the trial.

Should pregnant women receive the COVID-19 vaccine?

Thirteen pregnancies were studied during the course of the Moderna trial ( The severe adverse events reported included one spontaneous and one elective abortion, both of which occurred in the placebo group. It was noted that the “FDA review of this study concluded that mRNA1273 given prior to mating and during gestation periods at dose of 100 μg did not have any adverse effects on female reproduction, fetal/embryonal development, or postnatal developmental except for skeletal variations which are common and typically resolve postnatally without intervention.”

23 pregnancies were followed in the Pfizer-BioNTech trial, including 9 that withdrew due to pregnancy ( The FDA indicates that the “…participants continue to be followed for pregnancy outcomes.”

Does the COVID-19 affect fertility?

This is unknown. However, patients are being recruited to pursue the answer to this question: A small sample of patients were vaccinated before becoming pregnant and during pregnancy. Not all of the pregnancy outcomes are known at this time but the FDA review of this study concluded that “…mRNA1273 given prior to mating and during gestation periods at dose of 100 μg did not have any adverse effects on female reproduction…”

Why is there concern that the COVID-19 vaccine make an individual infertile?

It was noted that there is a homology of several amino acids (building blocks of proteins) between the SARS-CoV-2 spike protein and a protein that is important for placental attachment, known as syncytin-1. The thought is that if a person makes antibodies against the COVID-19 vaccine, the ones directed against this region of homology will also recognize syncytin-1 and therefore prevent placental attachment. At present, it is not known if this can happen. However, this antibody, if it were a byproduct of immunity to the vaccine, would also be expected in natural COVID-19 infection, which will be difficult to completely avoid forever.

The process of antibody production is regulated and while auto-antibodies can be made, preventative mechanisms exist to prevent their production. Autoreactive cells are generally censored by the immune system.

To date, the only autoantibody that have been recognized to potentially play a role in the COVID-19 disease process is directed against type I interferons (Bastard, P. and Rosen, LB. Autoantibodies against type I IFNS in patients with life-threatening COVID-19. Science 2020; 370: eabd4585. eabd4585. doi: 10.1126/science.abd4585.

In other words, for this to happen, the body first needs to make this exact antibody, then it needs to be effective

The CDC guides that pregnant women may have a more severe course with COVID-19 infection. However, CDC concedes that there is limited data regarding vaccination safety in this population (

How are adverse events being reported after the trials?

CDC is taking information via an app known as v-safe. Adverse events can be reported through

Who should not get the vaccine?

Currently, anyone younger than the recommended groups (less than 18 years old for the Moderna vaccine and less than 16 years old for the Pfizer-BioNTech vaccine) as well as anyone that will likely have a severe allergic reaction or had a severe reaction to the first vaccination (; see below).

Should patients with autoimmune and immunodeficiency (weakened immune systems) diseases receive the vaccine?

Currently, the CDC guidance indicates that these patient groups may be at increased risk for COVID-19 infection. However, it concedes that there is insufficient safety data with regard to COVID-19 vaccination in these groups (

Who needs to worry about allergies to the vaccines?

At present, anyone who has had an allergic reaction to a previous COVID-19 vaccination, a previous allergic reaction to an mRNA vaccination and anyone who has had an allergic reaction to one of the excipients of the vaccination. Currently, the most likely cause of allergy is polyethylene glycol (PEG). Anyone with a reaction to PEG or any other polysorbate, with which PEG is crossreactive, should not receive the vaccination (; Those patients who have had previous reactions to vaccinations should see their doctor. The CDC reports excipients present in vaccines its database ( The Institute for Vaccine safety also publishes the amount of excipients per 0.5 mL dose ( According to this database, there are 22 vaccinations that contain polysorbates.

In addition, the FDA publishes an exhaustive list of all vaccines approved for use in the United States (

The Vaccine Adverse Event Reporting System (VAERS) has monitored the rate of anaphylaxis between December 14-23, 2020 and estimated it to be 11.1 per one million doses (Allergic Reactions Including Anaphylaxis After Receipt of the First Dose of Pfizer-BioNTech COVID-19 Vaccine — United States, December 14–23, 2020; MMWR Morb Mortal Wkly Rep 2021;70:46–51). Of the persons with reported allergic reactions, 81% had a history of anaphylaxis. There were also 86 cases of non-anaphylactic allergic reactions, 61 nonallergic adverse events, and 7 events that are still under investigation. The onset of symptoms occurred within 15 minutes for 71% of patients; between 15-30 minutes for 14% of patients; and more than 30 minutes for 14% of patients.

How many people need to be vaccinated to establish herd immunity?

Herd immunity occurs when enough people in a population have immunity to prevent successful propagation of an infectious disease. For Coronavirus, estimates are as low as 70% ( Others, like Dr. Anthony Fauci estimate that this will require 90% of our population to be vaccinated or previous infection with COVID-19 ( -require-nearly-90-to-get-coronavirus-vaccine-idUsln2J411V).

How long do COVID-19 antibodies last?

Antibodies, one of the primary means by which our body protects us against COVID-19, have been shown to last up to 6-8 months with a slight drop at that time (

Now, some myths that myself and my colleagues have heard and my comments based on the available data. Please also see the detailed explanation above.

Myth: If I have allergies, I should not take the COVID-19 vaccination.

Truth: Well, that depends. If you have a known allergic reaction to one of the vaccine components, this would be true. However, if you have allergies to something else, there is no need for concern. Similarly, if you are allergic to a bee sting but never have had issues with eating peanut butter, you would not be concerned about peanut-allergy, but you should avoid bees and bee stings.

The CDC currently recommends that people who have had an immediate allergic reaction to the first COVID-19 vaccine or who have had an allergic reaction to one of its components, in particular Polyethylene glycol, or a component that is cross-reactive (like polysorbate), avoid the COVID-19 vaccination. If you have had a reaction to another vaccine, it is recommended you see your doctor for further advice.

Myth: The COVID-19 vaccines kills people.

This is not believed to be the case, at least not in the FDA-approved trials to date.

Two vaccine recipients and four placebo recipients died in the course of the Pfizer-BioNTech trial ( Of the two that received the vaccine, one died from arteriosclerosis three days after receiving dose one. One participant had a cardiac arrest 60 days after the second dose and died 3 days later. Of the four participants in the placebo group, two had no known cause, one died from hemorrhagic stroke and one died from myocardial infarction. “No deaths were considered by the investigators to be related to vaccine or placebo (Polack, FP, et al. Safety and Efficacy of the BNT162b2 mRNA Covid-19 VaccineN Eng J Med 2020; 383: 2603-15).”

As of December 20, 2020, of the participants in the Moderna trial, there have been 13 deaths (6 in the vaccine group and 7 in the placebo arm) ( Of them, two deaths in the vaccine group in participants over 75 years of age, both with pre-existing cardiac history. One participant died of cardiopulmonary arrest 21 days after dose 1 and one died of myocardial infarction 45 days after dose 2. Two participants in the vaccine arm were found at home, with cause of death undetermined, one a 70-year old with heart disease found 57 days after the second dose. Another was a 56-year old participant with hypertension, chronic back pain being treated with opioid medication found 37 days after the first dose. The cause of death was regarded as head trauma. One case was a 72-year old with Crohn’s disease and short bowel syndrome hospitalized 40 days after the second dose for thrombocytopenia and acute renal failure due to obstructive nephrolithiasis that died of multiorgan failure. One suicide occurred 21 days after the first vaccination. Those receiving placebo died of myocardial infarction, abdominal perforation, systemic inflammatory response from known malignancy, COVID-19, and one of unknown causes. The FDA commented that the “deaths represent events and rates that occur in the general population of individuals in these age groups.”

Myth: Natural immunity is better than vaccine-generated immunity

Truth: Sometimes this is true. In cases in which the immune response is overly vigorous and plays a role in causing Acute Respiratory Distress Syndrome (ARDS) or other immune reactions such as those of a severe COVID-19 infection course that may lead death, however, the natural immune response is clearly not superior. Vaccination does not prevent a natural infection with COVID-19, it causes the immune response to be more efficient should a natural infection occur.

Myth: COVID-19 vaccine is made from the same protein as placental protein and will make me infertile

Truth: COVID-19 vaccine has no placental protein at all. The ingredients of both vaccines are listed on the FDA website. Both contain the messenger ribonucleic acid (mRNA) that encodes for the SARS-CoV-2 Corona spike, some lipids to house the fragile mRNA and stabilize the nanoparticle structure, some salts to maintain the pH and charge of the lipids, and a sugar, sucrose.

Myth: The COVID-19 vaccine does not work

Truth: The vaccines are considered 95% effective. Most importantly, no participants in the course of the Pfizer-BioNTech and Moderna studies that contracted COVID-19 died. Better still, the majority did not have significant infection either.

Myth: The COVID-19 vaccine will lead to cancer in 10-20 years

Truth: The reality is that we do not have safety data that extends beyond several months. However, there is currently no proposed realistic mechanism whereby the COVID-19 vaccine causes cancer.

Myth: The COVID-19 vaccine has dead pig cells.

Truth: There are no dead pig cells. Just mRNA, a lipid coat, some salts, and a sugar.

Myth: The COVID-19 vaccine will alter my genes

Truth: Our genes are made of DNA and the vaccine contains mRNA. The contents of the mRNA were manufactured and are limited. They do not contain any of the necessary and very complicated machinery for this to happen. First, DNA is housed in the nucleus, away from mRNA in the cytoplasm of a cell. Second, it would take a specific enzyme, known as a reverse transcriptase, to make DNA from mRNA. This is not present in human cells, the Coronavirus, or in the vaccine. Finally, mRNA from the vaccine and even our own cells has a very short half-life, and is degraded or destroyed in hours.

There is some research ( that suggests if a person is infected with one of the few viruses that contain a reverse transcriptase at the time of vaccination, there may be integration of the COVID-19 sequence. However, to date this has not been shown to be an issue nor are the implications clear. With regard to HIV, the CDC has giving guidance that persons with weakened immune systems might have an increased risk of severe COVID-19 infection but concedes that while “People living with HIV were included in clinical trials, though safety data specific to this group are not yet available at this time (

Myth: I can get COVID-19 and transmit the infection if I get vaccinated.

Truth: The complicated machinery of the virus that allows formation of complete COVID-19 viral particles and therefore allows infection are not included in the vaccine. The mRNA encodes one protein and this protein is included to generate an effective immune response. mRNA is very fragile and is quickly and easily degraded by cells. This is not regarded as likely.