Updated on September 3, 2024.
As of August 2024, three COVID-19 vaccines are approved by the U.S. Food and Drug Administration (FDA) for use in the United States. Each of these vaccines—created by Moderna, Pfizer-BioNTech, and Novavax—are safe and effective at preventing serious illness from SARS-CoV-2, the virus that causes COVID-19. They have played a critical role in controlling the COVID-19 pandemic.
Being vaccinated can prevent you from getting COVID-19. Even if you do become infected with the coronavirus, vaccination could prevent you from becoming seriously ill. Vaccination also helps protect vulnerable people in your family and community who are at high risk for a severe case of the disease.
Most people will experience either no side effects or very mild side effects from COVID-19 vaccination. Mild, temporary side effects might include soreness at the injection site, fatigue, muscle and joint aches, headache, and fever. Severe allergic reactions are rare. In rare instances, health problems can follow a vaccination, but these may not be related to the vaccine.
Despite the strong safety record of the COVID vaccines, online misinformation has prompted a range of questions and misconceptions about how they are made, how they work, and how the body responds to them.
So, when making the decision to vaccinate, it’s critical to separate fact from fiction. Here are several persistent myths about COVID-19 vaccines—and why they’re not true:
Myth: If you’ve had COVID-19, you don’t need to be vaccinated
Fact: Even those who have had COVID-19 and recovered from the infection need to be vaccinated. Having COVID once or even several times does not mean that you won’t get it again. People do get COVID more than once.
When a person is exposed to a virus like SARS-CoV-2, the body creates antibodies in response. Antibodies are proteins in the immune system that attach themselves to disease-causing agents, like viruses. This helps the immune system identify and destroy the disease-causing agent.
After a person recovers from COVID-19, antibodies may stay at a protective level in their body for a little while. The length of time depends on whether the infection was mild or serious, how much time has passed since the infection, and how old the person is.
That said, the short-lived protection that may come from being ill with COVID-19 isn’t as reliable or strong as the protection you can get from a COVID-19 vaccine. Everyone, regardless of whether they’ve had COVID, should be vaccinated and they should also stay up-to-date on their COVID vaccines to prevent becoming severely sick from a new variant of the virus.
Myth: The COVID-19 vaccine could make you sick
Fact: Some have claimed that the COVID-19 vaccine could cause you to become ill with the live version of the coronavirus or could cause you to shed (and spread) the virus. In fact, the COVID-19 vaccines currently available in the United States do not contain the live virus that causes COVID-19. That means they can’t give you the disease and they can’t shed or release live virus outside the body at the injection site.
Both the Pfizer-BioNTech and Moderna vaccines are mRNA vaccines. They work by using lab-created messenger RNA, also called mRNA. This substance carries instructions for the body to make a certain protein, called the spike protein, that SARS-CoV-2 uses to infect cells. This process triggers an immune response in the body that helps you resist the disease without encountering any infectious material or live virus.
The Novavax vaccine works differently. It’s what’s known as a protein subunit vaccine. Rather than teach the body to make spike proteins, this type of vaccine already contains spike proteins. It also contains adjuvant, an ingredient that helps teach the immune system how to remember and fight that spike protein in the future. In a way similar to the mRNA vaccines, this process helps immunize you against COVID-19. Likewise, it does not contain any live virus.
Myth: The COVID-19 mRNA vaccines could alter your DNA
Fact: Getting a COVID vaccine will not change your DNA (your genetic code). That’s because, in the case of mRNA vaccines, mRNA is made by DNA in a process that cannot be reversed. In other words, mRNA cannot backtrack into DNA.
There are some viruses that are RNA viruses that do get into your DNA, like HIV. RNA viruses that get into DNA have a certain enzyme that allows that to happen. But that enzyme does not exist in mRNA.
Myth: If you got the flu shot, you don’t need the COVID-19 vaccine
Fact: Everyone six months and older (with rare exceptions) should receive both the flu vaccine and the COVID-19 vaccine. You need to get both because COVID-19 and the flu are completely different viruses. The flu shot provides no protection against COVID-19.
Myth: The COVID-19 vaccine has a microchip in it to track and control people
Fact: There is no microchip in the vaccines. COVID-19 vaccines are intended only to protect public health by fighting against disease.
The origin of the microchip myth seems to stem from a statement made by Bill Gates in 2020 when discussing tracking vaccination progress in Africa. There is a general lack of medical records in Africa. Public health officials could therefore, in theory, use infrared light to see if a person had gotten the vaccine or not. But this process had nothing to do with microchips or tracking people.
In fact, the idea never came to fruition. What’s more, it’s not technologically possible to make a microchip small enough to be administered via a vaccine.
Myth: The COVID-19 mRNA vaccines were developed with fetal tissue
Fact: The vaccine was not made with tissue from fetuses or other types of organic tissue. Instead, mRNA vaccines are made synthetically in a laboratory. The vaccines do not use any kind of organic fetal tissue, viral cultures, or live matter.
Myth: The COVID-19 vaccines contain dangerous ingredients like metals and preservatives
Fact: The COVID-19 vaccines do not contain any harmful ingredients. That includes metals, food proteins, antibiotics, latex, preservatives, medicines, or toxins. Instead, they contain only ingredients that are needed to securely store and effectively deliver the vaccine to fight disease.
Myth: COVID-19 vaccines cause new variants of the disease
Fact: New variants of the virus that causes COVID-19 arise because of the way the virus itself naturally mutates over time.
COVID-19 vaccines have nothing to do with creating or causing new COVID-19 variants. Rather, as the virus spreads through the population, it has more chances to change. If anything, widespread vaccination may help reduce the development of new variants.
Myth: COVID-19 vaccines cause problems with fertility
Fact: There is no evidence that any vaccines (whether for COVID-19 or other diseases) can cause problems with trying to get pregnant.
In fact, the Centers for Disease Control and Prevention (CDC) recommends that all pregnant people receive the most up-to-date COVID-19 vaccine because it’s a safe and effective way to protect themselves and their babies from serious illness.
Myth: Getting COVID-19 is less risky than the possible side effects of the vaccines
Fact: In the vast majority of cases, the COVID-19 vaccines have relatively mild side effects.
Ongoing safety monitoring by the federal Vaccine Adverse Event Reporting System (VAERS) continues to identify a very low risk of any health problems following vaccination for COVID-19.
According to a 2023 study published in Vaccines (Basel), there were fewer than nine cases of severe allergic reactions (called anaphylaxis) per million doses of the vaccine, measured between December 2020 and January 2023. There were fewer than 1.5 cases of anaphylactic shock per million doses. Most of the cases that were reported did not result in death and no deaths from anaphylaxis were associated with the vaccine types available in the U.S.
On the other hand, even though death rates from COVID-19 infections have declined in the years since the pandemic began, in the winter of 2023 to 2024, there was still a nearly 35 percent higher chance of dying after being hospitalized with COVID-19 compared to being hospitalized with seasonal flu.
In addition to the risks posed by the symptoms of a COVID-19 infection, long COVID is another concern. This is a serious illness that can damage their heart, brain, lungs, and kidneys. People may have chronic symptoms that can persist after the worst of the acute illness ends—for weeks, months, or even years.
There is still much to be learned about long COVID, and there is currently no treatment for it, but vaccination is the best tool available to prevent it.
Myth: After you're vaccinated, you'll never need to wear a mask again
Fact: Even after you’re vaccinated against COVID-19, you should still wear a mask in certain situations. For example, you should wear a mask if you are around people with compromised immune systems, especially if you believe you may have been exposed to the SARS-CoV-2 virus.
Despite their high level of safety and effectiveness, the vaccines do not completely protect you from getting COVID-19. People who have been vaccinated and are up-to-date on their vaccines can and do sometimes get COVID-19. But vaccination helps protect you from becoming seriously ill from COVID-19—and spreading the infection to others.