COVID-19 vaccine myths, busted

This page was reviewed on October 12, 2021

We’ve busted a few COVID-19 myths in our time and with the vaccines rolling out across the world, we thought it was time to tackle a few vaccine related myths too.

Myth: The vaccines aren’t safe because they were developed quickly

While it’s true the vaccines have been developed quickly, this is not because any important or safety-related corners were cut.

Part of the reason why the process was so fast was that the vaccine technology used to make COVID-19 vaccines isn’t totally new. Also, scientists have been able to draw on their knowledge of other coronaviruses that they have studied in the past.

Alongside this, everyone involved in the process worked really hard and collaboratively. This meant clinical trials could happen quickly and safely, leading to faster approval of the vaccines.

Once a vaccine is developed, it can take a long time to recruit volunteers and see how well the vaccine works. In this case, tens of thousands of volunteers came forward right away and, due to high rates of COVID-19 in the population, it didn’t take long to see that the vaccines were effective.

The Pfizer vaccine has now been fully approved by the FDA for the prevention of COVID-19 disease in individuals 16 years of age and older.

Myth: We don’t need the vaccine because the recovery rate from COVID-19 is high and natural immunity is better

While it’s true that most people who get COVID-19 don’t become seriously sick, this still means that a lot of people do, and many have died.

Older people are more likely to become seriously sick, but some younger people do too. There’s no way to know how you will respond to the virus.

We don’t yet know how long you might be naturally immune if you get sick and then recover from COVID-19. We also don’t know how long you might be immune after you’ve had the vaccine. Vaccines can give different levels of protection compared with natural immunity. But we need more research to fully understand this. 1,2,3

The safest way to get protected is to get vaccinated.

Myth: You can get COVID-19 from the vaccines

No, this isn‘t possible because the vaccines do not include live COVID-19 virus.

There are different types of vaccines available. They all work by training our immune system to recognize the COVID-19 virus and fight it. You can find out more about the different vaccine types here.

Myth: The COVID-19 vaccines will alter your DNA

None of the vaccines alter your DNA.4

Two of the vaccines - the Pfizer mRNA vaccine and the Moderna vaccine - use a new technology, which is why this myth sometimes comes up. This vaccine works by giving your cells a set of instructions for how to make a new part of the COVID-19 virus, called the spike protein.

Your immune system then recognizes the spike protein as something foreign in the body and starts an immune response against it. mRNA never enters the nucleus, where your own DNA is.

A great thing about mRNA vaccines is that they don’t contain any live parts of COVID-19 and can be produced quickly in a lab.

Myth: I already had COVID-19 and I have recovered, so I don't need to get a COVID-19 vaccine when it's available

Unfortunately, re-infection with COVID-19 is possible. So, if you’ve had COVID-19 and are offered the vaccine, doctors still recommend you to take it. We still don’t know how long you are protected against COVID-19 after having been sick and recovered from the infection. This ‘natural immunity’ is likely to vary between people.2

Scientists are monitoring this closely and in time we will know more about how long both natural and vaccine mediated immunity lasts.

Myth: The COVID-19 vaccines cause severe symptoms in most people

Like any vaccine, the COVID-19 vaccine can cause side effects, but most are mild and short-term. The most common side effects include.5

  • Pain, redness or swelling on your arm where you got the shot
  • Fever
  • Feeling tired
  • Headache
  • Muscle aches
  • Chills
  • Nausea

These side effects don’t usually last more than a few days to a week. You can talk to your healthcare provider about taking an over the counter pain reliever such as acetaminophen or ibuprofen.

Keep in mind that a high fever could mean you have another infection or have COVID-19 that you caught before or around the time of the vaccination, before the vaccine had time to kick in. Some people have more severe side effects that affect their ability to do normal daily activities. If you feel unwell or are worried, it is a good idea to speak to a healthcare professional about it.

A small number of people have had a severe allergic reaction after getting the COVID-19 vaccine. This is called anaphylaxis. This is a very rare side effect which usually happens within the first 15 minutes of getting the vaccine. For this reason, when you have the vaccine you will be asked to stay nearby. The healthcare professionals who give the injections know how to manage anaphylaxis.

Myth: I will always test positive for COVID-19 after being vaccinated

There are two different types of COVID-19 tests used at the moment.

One type of test is used to find out if you currently have the virus (such as an antigen or PCR test). The COVID-19 vaccines will not give you a positive result with this type of test, as it only assesses whether you currently have COVID-19.

The other type of COVID-19 test, known as an antibody test, shows whether you have been infected with the virus in the past

A positive antibody test means that your immune system responded to the virus when you were sick. An immune response gives you at least some level of protection against COVID-19. Because the aim of the COVID-19 vaccination is to trigger an immune response to prevent you getting infected with the virus, it is possible that you may have a positive antibody test.6 However, experts are still exploring how the COVID-19 vaccination will affect this type of test result.

Myth: If I am pregnant or breastfeeding I cannot get the vaccine

COVID-19 vaccination is recommended for all people 12 years and older, including people who are pregnant, breastfeeding, trying to get pregnant now, or might become pregnant in the future.7 You might want to have a conversation with your healthcare provider about COVID-19 vaccination. While such a conversation might be helpful, it is not required before vaccination. Learn more about vaccination considerations for people who are pregnant or breastfeeding here.

If you are pregnant and have received a COVID-19 vaccine, we encourage you to enroll in v-safe, CDC’s smartphone-based tool that provides personalized health check-ins after vaccination. A v-safe pregnancy registry has been established to gather information on the health of pregnant people who have received a COVID-19 vaccine.



The information provided is for educational purposes only and is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Seek the advice of a doctor with any questions you may have regarding a medical condition. Never delay seeking or disregard professional medical advice because of something you have read here.