Both the Pfizer BioNTech and Moderna vaccines are based on ground-breaking technology that has been in development for over 30 years. In fact, messenger RNA (mRNA) was first discovered nearly 60 years ago. mRNA is a single-stranded molecule of RNA that corresponds to the genetic sequence of a gene and is read by a ribosome in the process of synthesizing a protein.
To put it more simply, Covid-19 mRNA vaccines provide instructions for our cells to make “spike protein”. The spike protein is found on the surface of the virus that causes Covid-19.
mRNA vaccines do not use the live virus that causes Covid-19 and therfore they cannot give someone Covid-19. They do not affect or interact with our DNA in any way, as mRNA never enters the nucleus of the cell, which is where our DNA (our genetic material) is kept.
Covid-19 mRNA vaccines are given in the upper arm muscle. Once the instructions (mRNA) are inside the muscle cells, the cells follow the instuctions and make the protein piece. After the protein piece is made, the cell breaks down the mRNA and gets rid of them. Next, the cell displays the piece of protein on its surface. Our immune system recognises that the protein does not belong there and starts to make antibodies. After developing antibodies, our immune system has learned how to protect against future infection.
The benefits of mRNA vaccines, like other vaccines, is that those vaccinated gain this protection without ever having to risk the serious consequences of getting sick with Covid-19.