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Rady Children's Specialists

Myths & Facts


Can the COVID-19 vaccines cause COVID-19 infection?

No. None of the currently approved vaccines in the US (Pfizer-BioNTech, Moderna and Janssen [Johnson & Johnson]) contain the live SARS-CoV-2 virus that causes COVID-19. It is important to understand how the different COVID-19 vaccines work. The goal of vaccines is to prepare the immune system to recognize parts of the virus once it enters the body. The SARS-CoV-2 virus is made up of 29 proteins and the virus uses what is called the “spike” protein to enter the body. The spike protein is the prickly projection on the surface of the SARS-CoV-2 virus and the part of the virus that our immune system recognizes as “foreign”. Currently, there are two different types of vaccines approved that help the immune system recognize the virus spike protein. The Pfizer-BioNTech and Moderna vaccines uses what’s called messenger RNA (mRNA), which provides a code for your own body to create a protein similar to the spike protein which prompts an immune response in the body. Unlike the mRNA vaccines, the Janssen vaccine is a viral vector vaccine that uses an adenovirus, which is a type of virus that causes the common cold but has been changed so it is unable to cause disease. The adenovirus (viral vector) is used to help educate the immune system to recognize the spike protein by carrying a gene from the virus into human cells, which then creates the spike protein. Since only the spike protein is being used to help the immune system recognize the virus once it enters the body, it is impossible for these vaccines to cause COVID-19 disease. 

Can the COVID-19 vaccines cause death?

Currently there are no known cases of a COVID-19 vaccine directly causing death. Many people receiving the vaccines are elderly or people with severe underlying conditions who may pass away shortly after receiving a vaccine for reasons not associated with vaccination. Severe or life-threatening allergic reactions, e.g. anaphylaxis, occur rarely after vaccination. All of those who have reported anaphylaxis after receiving a COVID-19 vaccine were treated and recovered.

Will the COVID-19 vaccines alter my DNA? 

No. The mRNA vaccines (Pfizer-BioNTech and Moderna) and the viral vector vaccine (Janssen) do not change or interact with your DNA in any way. The vaccines work with the body’s natural defenses to safely develop immunity to the SARS-CoV-2 virus. The mRNA in the Pfizer-BioNTech and Moderna vaccines never enters the nucleus of the cell, which is where our DNA is kept. This means that the mRNA cannot affect or interact with our DNA in any way. The mRNA uses the cell’s machinery to make the SARS-CoV-2 spike protein that our immune system recognizes, then enzymes in the cells breakdown and get rid of the mRNA. The viral vector in the Janssen vaccine never interacts with or changes our DNA. The viral vector uses the cell’s machinery to make the SARS-CoV-2 spike protein that our immune system recognizes, then enzymes in the body breakdown and get rid of the cells that contain the viral vector. 

Is it safe to get a COVID-19 vaccine if I want to have a baby one day?

Yes. People who want to get pregnant now or who plan to try in the future may receive a COVID-19 vaccine. There is no current evidence that immunity formed from COVID-19 vaccination causes any problems with pregnancy. There also is no evidence suggesting that fertility problems are a side effect from ANY vaccine.  

Do any contents of the COVID-19 vaccines stay in the body forever?

No. Enzymes in the body breakdown and get rid of all components of the vaccine after the immune response has started to develop. There are no microchips, implants, or tracking devices that are injected with the vaccine in order to track someone who has been vaccinated. This is a myth. Such devices are too large to be injected through a needle, and tracking devices require batteries. 

Were the COVID-19 vaccines made with any controversial substances?

No. The vaccines contain normal vaccine components, such as fats, salts and small amounts of sugars. Please see the FAQs for a list of ingredients in the vaccines currently authorized for use in the U.S. 

Specifically, the COVID-19 vaccines were not developed using fetal tissue or fetal cells taken from recent abortions, and they do not contain aborted fetal cells. Pfizer and Moderna performed tests to ensure the vaccines worked using fetal cell lines and Janssen uses fetal cell lines in vaccine development, confirmation and production. It’s important to have the full context: Fetal cell lines are not the same as fetal tissue. Fetal cell lines are cells that grow in a laboratory. They descend from cells taken from elective abortions in the 1970s and 1980s. Those individual cells from the 1970s and 1980s have since multiplied into many new cells over the past four or five decades, creating fetal cell lines. Current fetal cell lines are thousands of generations removed from the original fetal tissue. They do not contain any tissue from a fetus. The Vatican has issued clear guidance that permits Roman Catholics in good faith to receive COVID-19 vaccines that use fetal cell lines in development or production.

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