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COVID-19 vaccines. Get the facts.

Reviewed 1/25/2022

9 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 and Moderna vaccines have been shown to be more than 90% effective in preventing COVID-19. Each of these vaccines requires two doses to deliver that level of protection. The vaccine from Johnson & Johnson (J&J) 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 to the disease, but 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 and Moderna vaccines contain messenger RNA (mRNA). The mRNA teaches your cells to make a harmless protein from the coronavirus. That prompts your immune system to create antibodies to the virus, which help protect you if you're exposed. 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. J&J's vaccine can't affect or interact with your DNA either.

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

There is currently no evidence that COVID-19 vaccination causes 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.

Everyone 5 and older in the U.S. is now eligible to get a COVID-19 vaccine. The vaccines are not yet available to younger children. Check with your local health department to find out how to make an appointment.

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

The Pfizer 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 J&J 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 mostly minor.

Some, but not all, people have temporary side effects after being vaccinated. These are generally mild, such as:

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

A small number of people have experienced serious side effects, such as an allergic reaction or a rare type of blood clot. These are extremely rare. Talk with your vaccine provider about the emergency signs to watch for. And call your doctor if any mild symptoms last more than two days.

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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