A: No. The mRNA vaccines from Pfizer and Moderna contain a message which instructs your cells to make a protein shaped like a small part of the virus that causes COVID-19.
The message is called messenger RNA or mRNA. Messenger RNA only contains the information it takes to make a certain protein. This can’t change your DNA.
In your body, your DNA makes messenger RNA, which tells your cells to make specific proteins. Your DNA has all the information it takes to make you, you. Messenger RNA only contains the information it takes to make a certain protein. It is similar to an instruction manual to build a piece of furniture. Special-use proteins are built using the instructions from the mRNA and incorporating different amino acids as the building parts.
The mRNA vaccines from Pfizer and Moderna contain the mRNA to make one particular protein of SARS-CoV2–known as the spike protein. The mRNA is placed in tiny fat bubbles (aka lipid nanoparticles) so that the mRNA can get into our muscle cells. Once inside the cell, the mRNA tells our muscle cells to build the spike protein.
mRNA is not very stable. This means that it does not last within our bodies for very long. The fat bubble containing mRNA is also not very stable. The Pfizer vaccine needs to stay in an -80C freezer…which is -112F! The Moderna vaccine is more stable. It has to remain frozen for long term storage, but it is stable at 4C, roughly the temperature of a household refrigerator, for one month.
After your cells make the spike protein according to this “instruction manual,” the spike protein is recognized by the cells of your immune system. Your immune system makes antibodies that will recognize the same proteins when it sees them again.
There are 2 doses of the mRNA vaccines. The first dose “primes” the immune system. This gets the initial response underway. The second dose “boosts” the immune response, to lead to higher levels of antibodies and spike-protein reactive T cells. The full effect of immunity delivered by the vaccine happens after the second dose.
Side effects of the mRNA vaccines included temporary fatigue, muscle pain, joint pain and headache in a percentage of patients. These side effects are caused by the immune system’s reaction to the spike protein. Although these side effects are uncomfortable, they do not last very long and are certainly safer than contracting COVID-19, even in younger, healthy populations. The side effects were more common with the second dose of vaccine, which is when the immune response is being boosted. Your natural immune system responses are powerful, and when your immune system is in action you feel it!
A main advantage of mRNA vaccines is that they are faster to manufacture than other types of vaccines. . This is why the mRNA vaccines are ahead in development compared to the other vaccines. Making mRNA does not involve time-intensive steps like making and isolating proteins and then purifying the products. It does not involve the use of cells to make.
mRNA vaccines have been studied for many years, although the Pfizer and Modera vaccines are the first mRNA vaccines available. Thanks to many years of development and improving on the technology, the mRNA vaccines are set to make an impact to protect us in the pandemic.
Here’s a nice explainer we found from Nebraska Medicine: