5 COVID-19 vaccine myths and truths

These facts can help put myths about the new shots to rest

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There are many myths circulating about the new COVID-19 shots. Let’s separate fact from fiction. 

Myth: The mRNA vaccines will change your DNA 

Fact: The Moderna and Pfizer-BioNTech vaccines are made with a technique called messenger RNA (mRNA). mRNA teaches cells how to make certain proteins, according to the Centers for Disease Control and Prevention (CDC). The mRNA never enters the part of your cells where your DNA is stored. (DNA is the genetic code that determines your traits.) In these COVID-19 vaccines, the mRNA tells your body how to make the protein your immune system needs to fight the disease. Your body will learn how to recognize the COVID-19 virus and keep it out.  

The vaccine from Janssen (Johnson & Johnson) doesn’t affect your DNA either. It also teaches your cells how to make the needed protein. But it delivers those instructions in a different way. It uses a modified virus that’s different from COVID-19 to pass along the information that helps your immune system protect you from the disease. This modified virus is not dangerous to your health. 

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Myth: The vaccine isn’t safe because it was made too quickly 

Fact: The companies behind the 3 currently available vaccines (Pfizer-BioNTech, Moderna and Janssen) followed all necessary safety steps for use during this pandemic while making and testing their vaccines, according to the U.S. Food and Drug Administration (FDA). The vaccines were tested on tens of thousands of people, which is typical for vaccine trials. The FDA applied all its usual standards for emergency use before giving the green light to authorize the COVID-19 vaccines for emergency use.  

Also, while the Pfizer and Moderna shots are the first COVID-19 vaccines to use mRNA, the FDA notes that this technology has been around for about 30 years. Scientists were able to build on work that had already been done. 

Questions about COVID-19 testing or vaccines?  

We’ve gathered important information about testing services and vaccine access in one place — including answers to your most frequently asked questions. Find it all at our COVID-19 Resource Center.  

Myth: The side effects are worse than COVID-19 itself 

Fact: The vaccine cannot make you sick with COVID-19 since it does not contain any of the live virus, according to the CDC. While some people do feel side effects, most are mild to moderate, such as sore arm, fever or body aches. They usually go away in 1 or 2 days. On very rare occasions, people have had severe allergic reactions to the vaccine. The chance of this happening to you is very small, with only 2 to 5 people in a million, according to the CDC. 

To make sure you’re OK, you’ll be watched by a health care team for 15 to 30 minutes after getting your vaccine. If you have a history of severe allergies to other things, like certain foods, medications or bee stings, you’ll be watched for half an hour. 

Myth: I already had COVID-19, so I shouldn’t get the vaccine 

Fact. If you’ve already had COVID-19, you can still be reinfected with the virus, according to the CDC. If you currently have COVID-19, the CDC and FDA advise waiting until you’re fully recovered before getting the vaccine. Also, if you had COVID-19 and were treated with monoclonal antibodies or convalescent plasma, you should wait about 90 days after you’ve recovered.  

Myth: The vaccine may cause infertility  

Fact: Because of how the COVID-19 vaccines work in the body, there is no science to suggest a link between the vaccines and an increased risk of infertility. The same is true for breastfeeding infants, adds the CDC. Getting the COVID-19 vaccine is a decision each woman should make after talking with her doctor or health care professional.  

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The information in this story is accurate as of press time and posting. To limit the spread of the coronavirus, it’s important to continue practicing social distancing (keeping at least 6 feet away from people outside your household) and washing your hands frequently. You should also be appropriately masked any time you’ll be in public. According to the CDC’s latest guidance, this means layering a disposable surgical mask underneath a snug-fitting cloth mask or placing a mask fitter over your cloth mask to ensure a tight fit. Because the situation surrounding COVID-19 continues to evolve, we encourage readers to follow the news and recommendations for their own communities by using the resources from the CDC, WHO, and their local public health department. 

The information is a summary and is subject to change. The current FDA-authorized COVID-19 vaccines may not be appropriate for everyone. There are special considerations for people with certain conditions, of different ages, and who have had treatments such as monoclonal antibody therapy or convalescent plasma. If you have questions about the COVID-19 vaccine, talk to your health care provider or visit the CDC’s Frequently Asked Questions.

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