Vaccine Myths

Dartmouth Health recommends the COVID-19 vaccine, and we hope you will choose the vaccine when it is available for you. We understand that deciding whether to get a new vaccines can create many questions and concerns. To put your mind at ease, our medical experts have weighed in to dispel some myths and share facts, about the vaccine.

True or false?

Test your knowledge of COVID-19 vaccine myths. Do you know what the facts are? Check back as we add more myth busters to this page.

COVID-19 Vaccine Myth Busters

The COVID-19 vaccine will give you the coronavirus.


None of the COVID-19 vaccines contain the live coronavirus so it is impossible to get coronavirus from the vaccine. There is still a small chance that you could get COVID-19 after your vaccine. If you do, it would be from the environment and not the vaccine itself.

Once I get the COVID-19 vaccine I can stop wearing a mask and physical distancing from others.


Current Centers for Disease Control and Prevention (CDC) guidance says it is safe to gather indoors with other fully vaccinated people without a mask or social distancing except where required by federal, state, local, tribal, or territorial laws, rules and regulations, including local business and workplace guidance; however, mask use is still required on planes, buses, trains, and other forms of public transportation.

With reports of reduced vaccine efficacy against symptomatic disease of the Omicron variant, vaccinated individuals may choose to continue masking in areas with high rates of virus transmission as an added layer of protection. People who have not been boosted are encouraged to do so as boosters can improve efficacy against Omicron.

Immunocompromised patients with the potential for reduced immune responses to the COVID-19 vaccine are advised to still wear a mask, wash your hands, and practice physical distancing even after you get the COVID-19 vaccine.

There is no point in getting the COVID-19 vaccine because we don’t know how long the vaccine provides immunity.


Some populations may need to get a booster for the COVID-19 vaccine as different strains of the virus appear or vaccine protection wanes. That doesn’t mean that you shouldn’t get the vaccine as soon as it is available to you. As more time passes, and more people get vaccinated, health experts will begin to have a better idea of how long the immunity will last.

While some recent studies have shown decreased efficacy in the prevention of mild infections with the Pfizer-BioNTech vaccine at 4 to 6 months, the efficacy against severe COVID-19 and hospitalization remains strong for all vaccines. As we learn more about how long immunity lasts, additional patient populations may be recommended to receive boosters.

I have already had COVID-19 so that means I don’t need to get vaccinated.


Even if you have had COVID-19 you will still benefit from getting vaccinated, especially since there is evidence that people who have had COVID-19 can get it again. Early evidence suggests that natural immunity from COVID-19 can last anywhere from 4 to 8 months, but more research is needed in order to have a more accurate timeframe. In addition, data suggest that those who have had COVID-19 and have been vaccinated may be better protected against variants than vaccination alone.

The COVID-19 vaccine can change your DNA.


Both messenger RNA (mRNA) and viral vector COVID-19 vaccines work with your body’s immune system and “teach” it how to fight COVID-19. mRNA does enter your cells, but not in the part of the cell where DNA lives.

Viral vector COVID-19 vaccines deliver genetic material to the nucleus of the cell to allow our cells to build protection against the virus. However, the vector virus does not have the capability of integrating into your DNA.

The messenger RNA (mRNA) technology used in the COVID-19 vaccine is brand new.


Using mRNA in vaccines has actually been in development for almost 2 decades. It was created for this very reason: to be able to respond quickly to new viruses and illnesses, such as COVID-19.

The COVID-19 vaccine has severe side effects


Most individuals who receive the vaccine will experience mild and short-term side effects such as sore arm, headache, chills, fatigue, or muscle pain or fever. It is important to know that these side effects mean that the vaccine is working with your immune system as it should and will go away in a few days.

Although it is extremely rare, some people can have severe allergic reactions to ingredients used in a vaccine. That’s why experts recommend people with a history of severe allergic reactions—such as anaphylaxis (which is a severe, potentially life-threatening allergic reaction)—to the ingredients of the vaccine should not get the vaccination. Anyone who gets a COVID-19 vaccine is observed for a 15-minute period to ensure that there are no serious side effects. Those who have a history of vaccine reactions will be observed for 30 minutes.