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COVID-19 vaccines. Get the facts.

Reviewed 3/17/2021

10 facts and myths about COVID-19 vaccines

As you consider getting vaccinated for COVID-19, you may have questions. You might even feel nervous. That's OK.

Learning the facts about the COVID-19 vaccines can help you make a good choice for you, your family and your community.

Here's a look at some common COVID-19 vaccine myths and facts.

MYTH: Getting a COVID-19 vaccine can make me sick with COVID-19.

None of the current U.S. vaccines contain the live virus that causes COVID-19. Instead, the vaccines teach your immune system how to recognize and fight the virus. This keeps you from getting sick with COVID-19.

FACT: The vaccines are very effective at stopping COVID-19.

Both the Pfizer-BioNTech and Moderna vaccines have been shown to be about 95% effective in preventing COVID-19. Each of these vaccines requires two doses to deliver that level of protection. The vaccine from Janssen Biotech, Inc. (a Johnson & Johnson company) is given in a single dose and was about 72% effective overall in its U.S. trial and 85% effective against severe disease.

MYTH: I've had COVID-19, so I don't need a vaccination.

Having COVID-19 gives you natural immunity from the disease, but it's only temporary. Health experts don't know how long natural immunity lasts. There is evidence it may not last very long. So even if you've had COVID-19, you should still get vaccinated.

MYTH: The COVID-19 vaccines will alter my DNA.

The vaccines will not have any effect on your DNA at all. The Pfizer-BioNTech and Moderna vaccines contain messenger RNA (mRNA). The mRNA teaches your cells how to make a protein that fights the virus that causes COVID-19. But the mRNA never enters the nucleus of your cells, which is where DNA is found. It never interacts with your DNA in any way. Janssen's is a viral vector vaccine and can't affect or interact with your DNA.

FACT: The vaccines do not affect a woman's ability to have a baby.

There is currently no evidence that the antibodies formed after COVID-19 vaccination cause any problems with pregnancy. In fact, there is no evidence that fertility problems are a side effect of any vaccine.

FACT: I can get a vaccine for free.

The U.S. government has paid for vaccine doses with taxpayer money, so vaccines are being given to Americans at no cost. It's possible that vaccine providers may charge an administration fee for giving the vaccines, but this will be covered by insurance or by a special government fund if the patient is uninsured. No one will be denied a vaccine because of an inability to pay the administration fee.

MYTH: Anyone can get a vaccine right now.

Vaccine supplies are limited. That's why the Centers for Disease Control and Prevention is recommending vaccines be given to certain groups of people first. Each state has its own plan for deciding when different groups of people will be vaccinated. To find out when you're eligible for a vaccine, contact your state's public health department.

MYTH: The vaccines were developed too fast to know if they're really safe or not.

The Pfizer-BioNTech and Moderna vaccines use mRNA technology to produce antibodies to the COVID-19 virus. This technology had been in development for years before COVID-19 came into existence, so the researchers weren't working from scratch. The Janssen vaccine is a viral vector vaccine. Viral vectors have been studied since the 1970s. In addition:

  • China shared genetic information about the virus early on.
  • Researchers conducted all the usual testing steps. They just conducted them on an overlapping schedule to gather data faster.
  • Social media was used to find volunteers for vaccine tests.
  • Companies began making vaccines early on, so supplies were ready by the time vaccines were authorized.
  • The vaccines have gone through rigorous studies to be sure they are as safe as possible.

FACT: The side effects of the vaccines are minor.

Some, but not all, people have temporary side effects after being vaccinated. Side effects people have reported include:

  • Pain at the injection site.
  • Body aches.
  • Headaches.
  • Fever.

These side effects only last for a day or two. They are signs that your body is building immunity against the virus. You should call your doctor if symptoms last more than two days.

MYTH: I can stop wearing a mask after I get the vaccine.

It takes a few weeks for the body to develop immunity after a vaccine. In addition, we don't know yet if vaccines stop people from transmitting the virus. But we know that masks can. We may not be able to stop wearing masks or social distancing until most people have had the vaccine.

Do you know the myths and facts behind COVID-19 itself?

Learn what's true

Sources: Centers for Disease Control and Prevention; Johns Hopkins Medicine; National Institutes of Health

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