Skip to Main Content

8 COVID Vaccine Myths and How to Debunk Them

There are some of the most common myths you'll find shared and repeated.
8 COVID Vaccine Myths and How to Debunk Them
Credit: Elena Scotti - In-House Art

It’s been interesting to watch COVID vaccine rumors evolve (mutate?) in the months since the vaccines were first introduced.


At first, many of the myths were based on the fact that there was a lot we didn’t know about the vaccines. But there’s a lot less room for legitimate-sounding fear-mongering now that we have three different ones, they’ve been authorized in the U.S. for five months, multiple safety and efficacy studies have confirmed the initial trial data, and nearly half of Americans have had at least one dose.

These days, the myths out there tend to be recycled anti-vax tropes borrowed from disinformation campaigns about older vaccines—although plenty of the earlier rumors are still flying. Let’s investigate some of the more “popular” ones.

Myth: The vaccine can give you COVID

artist's conception of mRNA
Credit: nobeastsofierce - Shutterstock

None of the COVID vaccines can give you a COVID infection, for the simple reason none of them contain the virus (called SARS-CoV-2) that causes COVID.

There are some vaccines in the world that contain a killed or weakened version of the microbe they are trying to protect you from. But none of the COVID vaccines are constructed this way.

The Pfizer and Moderna vaccines only contain a piece of mRNA that our bodies can use to make the spike protein, a tiny piece of the virus. The shot only contains the mRNA and some ingredients that help the mRNA to make it into your cells. That means:

  • It does not contain the virus itself.

  • It does not contain any of the proteins from the virus.

  • It does not contain the virus’s full RNA, just the part that codes for the spike protein.

This all means that it does not—and cannot—give you COVID. The virus just isn’t there. The virus is also not involved in the process of producing the vaccine.

The Johnson & Johnson vaccine is made differently, but it also does not contain the SARS-CoV-2 virus. Instead, it uses a modified adenovirus (similar to the one that causes the common cold) with a piece of DNA that codes for the SARS-CoV-2 spike protein.

Myth: The vaccine can alter your DNA

healthcare worker drawing a vaccine into a syringe
Credit: Guillermo Legaria - Getty Images

The coronavirus has RNA for its genetic material, and we have DNA for ours. But the two are not interchangeable. Your DNA is safe.

Your DNA lives in the nucleus of each of your cells, and our bodies make mRNA copies of our DNA as part of the normal daily business of keeping us alive. The Pfizer or Moderna vaccine introduces a new mRNA that wouldn’t normally be there. mRNA does not alter DNA. (You can read more in our explainer about how mRNA vaccines work.)

The Johnson & Johnson vaccine does contain DNA, but the cells of our body don’t just let any old DNA into the nucleus to become part of our genetic material. Our cells protect themselves by destroying DNA and RNA they find floating around, so neither the DNA in this vaccine nor the mRNA in the others stick around very long.

Now, there are other viruses in the world, called retroviruses, that can make DNA from RNA and that can, in some cases, insert themselves into DNA. But that’s not relevant here because the coronavirus is not a retrovirus. It uses RNA but does not know how to make DNA. The adenovirus used in the J&J vaccine also lacks this ability.

Neither the virus nor the vaccine includes a reverse transcriptase, a special molecular machine that is necessary to make DNA. Even if reverse transcriptase were to be present in the cell somehow, neither the viral RNA nor the vaccine mRNA include the necessary binding sites for for the reverse transcriptase to work.

Or if you’d like an analogy, think about your DNA as a reference library. The books stay in the library, but perhaps a visitor brings their own book (another piece of DNA) or some notebook paper (RNA) to use while they’re in the library. There’s no way for the book or notebook to accidentally get sucked into the library’s permanent collection.

Myth: The vaccine contains scary ingredients

pharmacist draws a vaccine from a vial
Credit: Tong_stocker - Shutterstock

The vaccines’ ingredient lists are simple and straightforward, with no ingredients that are considered significant threats to human health, and no aluminum, mercury, or human cells. The ingredient lists for both mRNA vaccines contain just three types of ingredients:

  • the mRNA

  • lipids with very long names (these are basically fancy oils and they form the coating around the mRNA)

  • sugars, salts, and/or simple chemical buffers

In the Pfizer vaccine, the third category includes potassium chloride, monobasic potassium phosphate, sodium chloride, dibasic sodium phosphate dihydrate, and sucrose. These may sound scientific, but three of them you probably have in your kitchen (sucrose is sugar, sodium chloride is salt, and potassium chloride is sodium-free salt). Here is the fact sheet for the Pfizer vaccine, which includes the ingredients list.

The Moderna vaccine is formulated with different ingredients, but along the same formula. Besides the mRNA and lipids, it includes tromethamine, tromethamine hydrochloride, acetic acid, sodium acetate, and sucrose. Again, these are extremely common, simple ingredients in medical solutions. Tromethamine is just Tris buffer, which you may have used in science class. Acetic acid is the sour component of vinegar. Sucrose is sugar. Here is the fact sheet for the Moderna vaccine.

The Johnson & Johnson vaccine contains the adenovirus with the SARS-CoV-2 spike protein, salts, ethanol (alcohol), a preservative called polysorbate-80, and a chemical called 2-hydroxypropyl-β-cyclodextrin that keeps the vaccine components properly mixed. Here is the fact sheet for the Johnson & Johnson vaccine.

Even before COVID, there was a lot of misinformation floating around about vaccines. Sometimes, people heard that a certain ingredient was in some vaccines and jumped to the conclusion that it must be in all vaccines. Like mercury, for example, which is only in a very few vaccines. (It used to be in more.) So let’s go through a few items that are not in the COVID vaccine:

  • The COVID vaccines do not contain aluminum or mercury.

  • The COVID vaccines do not contain any preservatives (except polysorbate-80 in the J&J)

  • The COVID vaccines do not contain fetal cells.

  • The COVID vaccines do not contain microchips.

There are no fetal cells in the COVID vaccines

Some vaccines are developed in cell lines that are grown in labs, and in some cases those cells are descended from cells that were originally grown from human fetal tissue. This has led to a myth that “pieces of aborted babies” are in vaccines, which is not true at all.

The Pfizer and Moderna COVID vaccines are not grown in cells, fetal or otherwise. Remember, they’re just an mRNA. Lab machines can synthesize those without getting any cells involved whatsoever. Both Pfizer and Moderna did use some fetus-derived cell lines for some of the testing they did in the process of developing the vaccine, but not for making the vaccine itself.

The Johnson & Johnson vaccine does use a fetal cell line in its production, but no fetal cells are in the vaccines themselves. Also, to be totally clear, the production of the vaccine does not require new fetal cells to be collected; the cells are grown in the lab and derive from an 18-week fetus that was terminated in 1985.

If this is an issue for you or your loved ones, a Pope-approved statement from the US Conference of Catholic Bishops may help to understand how a vaccine tested on fetal-derived cell lines fits in with an anti-abortion religious framework. The bishops argue that the “remote connection” of vaccine development to abortion should not interfere with the fact that “being vaccinated safely against COVID-19 should be considered an act of love of our neighbor and part of our moral responsibility for the common good.” (The same group recommends that Catholics choose the Pfizer or Moderna vaccines when possible.)

Myth: The vaccines contain microchips or something magnetic

The idea that vaccines contain microchips is just flat-earth-caliber wrong. A whole conspiracy theory was whipped up from thin air about microchips in vaccines, and throughout 2020 it was shared in groups that discuss Qanon conspiracies and anti-vaccine propaganda. It is not based on any real-world truths whatsoever.

There are injectable microchips in this world, and your pet can get them at any vet’s office. (They also don’t really do anything, since they don’t have a battery; their only job is to store a serial number.) Sometimes pets get their microchip at the same appointment where they get a vaccine. Maybe that’s where the rumor started?

If you’ve ever seen a microchip injected, you’ll know that they’re a little bigger than a grain of rice, and the needle that delivers them is sized to match. In other words, the inside of the needle is big enough to fit a grain of rice. Meanwhile, the needles that deliver vaccines are extremely thin, less than 1 millimeter wide. Here is Vice President Pence getting his COVID shot in front of news cameras. You can see the needle is normal sized. There’s no microchip in there.

There’s a related rumor going around TikTok where people supposedly demonstrate that their arms are magnetic after getting the vaccine. I heard this rumor just as I hit the two-week mark, when I was considered fully vaccinated, so I ran down to the kitchen and tried to stick a bunch of magnets to my arm. That’s the video you see above. None of the magnets stuck.

Myth: Vaccinated people “shed” virus

person with mask
Credit: TommyStockProject - Shutterstock

Vaccinated people don’t pose a danger to unvaccinated people. There is a grain of truth to the idea of vaccine “shedding,” and that is specific to just a few vaccines—including the oral polio vaccine, which is not even used in most of the world. This vaccine uses a live attenuated (weakened) version of the polio virus, and it can potentially infect others.

Other live attenuated vaccines may pose a very small risk of shedding under specific circumstances—but none of the COVID-19 vaccines are live attenuated vaccines.

The idea that people who have had a COVID vaccine shed virus, or that they shed anything else (spike proteins, “GMOs”) is a completely made up myth.

Myth: The COVID vaccines will affect female fertility

pregnant woman getting a vaccine
Credit: Africa Studio - Shutterstock

The trials for both COVID vaccines excluded people who were pregnant, so we have limited data on their safety and effectiveness during pregnancy. But based on how these vaccines work, scientists and doctors say there is no reason to believe the shot would be harmful to people who are pregnant, lactating, or planning to become pregnant.

The American College of Obstetricians and Gynecologists has stated that it believes the vaccine “should not be withheld” from people who are pregnant even though the trials did not include them. The CDC agreed when they wrote the vaccine recommendations, saying that people who are pregnant have the choice of taking the vaccine and should talk to their provider to decide whether it makes sense for them.

Meanwhile, there is a rumor going around that the spike protein mRNA bears a similarity to a protein in the human placenta. If true, that would suggest that antibodies to the coronavirus would also react to the placenta, and could interfere with pregnancy. If you’ve heard the incorrect statement that the vaccine can “make you sterile” or “cause infertility,” this is probably the myth the person is thinking of.

But, again, this isn’t supported by evidence. In fact, we have a pretty good reason to believe it is not the case: The spike protein encoded by the mRNA is the same as the one on the actual coronavirus. So if antibodies to the coronavirus could cause problems with pregnancy, that would be just as true for people who got the virus naturally as for those who got the vaccine. But that turns out to be a moot point because there does not seem to be any meaningful match between the spike protein and placenta.

But don’t just take my word for it. If you’re pregnant or thinking about getting pregnant, talk to your doctor about what risks and benefits the COVID vaccine could pose for you personally.

Myth: Vaccine development was rushed

art of a syringe looking like a fighter jet
Credit: Chelsea Beck

The vaccine was developed quickly, and it was rolled out and distributed far faster than any other vaccine in history. But that doesn’t mean that it’s untested or that corners were cut.

Each of the two vaccines was tested in a study of over 30,000 people, in which half got the vaccine and half did not. Bottom line, there’s plenty of data to back up the belief that the vaccine is safe and effective.

Myth: Deaths and scary side effects are being hidden

hands with vaccine syringe
Credit: myboys.me - Shutterstock

For most people, the side effects of the COVID vaccines are what you’d expect from an immune reaction. Those include soreness and possibly redness or swelling in the arm where you got the vaccine, and potentially a day or two of fatigue and fever. As with other vaccines, the severity of these side effects varies from person to person.

If you’ve heard about serious side effects, they fall into two categories: ones that are real or plausible, and ones that are just made up to scare people on social media.

The most concerning of the real ones is that several people who got the Johnson & Johnson vaccine developed a rare type of blood clot. This was discovered through the Vaccine Adverse Event Reporting System, a government database that collects reports of possible side effects or health conditions that seem to be related to vaccines. (Regulators then investigate and verify the reports that seem serious.)

In response, regulators recommended that providers stop giving the vaccine until they could gather more information on how dangerous the vaccine actually is. After deciding that the risk of clots is real but very small, they recommended that vaccination could resume as long as providers and patients are aware of the risks. (The risk of getting a life-threatening clot from the vaccine is much smaller than the risk of getting one from COVID-19 itself.)

There are other safety concerns, as with any medical interventions. For example, a few people had serious allergic reactions, and the National Institute for Allergy and Infectious Diseases is now planning a study to learn more about this. If this is a side effect caused by the vaccine, it seems to be extremely rare.

But if you’ve heard other weird or scary stories, chances are they were probably made up for clicks. Don’t just trust blindly; look into it. For example, a nurse fainted after receiving the vaccine (people faint after injections sometimes, it’s fairly common), and a rumor has been circulating that she died. She did not. Or to take another example, a woman who was in a vaccine trial developed a scary skin condition on her feet, and posted online that she thought it was because of the vaccine. It turned out that she was in the placebo group, and had not received the vaccine at all. But her story kept circulating.

Recently, anti-vaccine activists have been browsing VAERS, the database of potential vaccine injuries, and either manipulating the data or publicizing unverified reports. Remember, US regulators paused administration of the J&J vaccine based on (at the time) just six cases of life-threatening clots, so it’s just not plausible that people are dropping dead and being ignored.

This post was originally published in December 2020 and was updated on May 20, 2021 to include new myths and to account for the J&J vaccine and the further information that we have learned since then.