We learned last time that vaccines usually work by injecting a dead or barely alive version of the bacteria or virus into our body so our immune system can learn how to attack it. The COVID vaccine is different, in that we will not get weak COVID injected into our system. Instead, we will get an injection of instructions for our muscle cells to make a piece of the COVID virus. Our bodies will know that this is an invader and make a chemical, called an antibody, to attack the invader. Once we can destroy this piece of the COVID virus, the virus cannot live, and we are protected.
The instructions to make the COVID piece is called messenger RNA, or mRNA. Remember when we talked about DNA being the cookbook? Well, mRNA is like your hands. The cookbook needs something to turn the pages to find the right recipe, assemble all the ingredients, mix them and cook them. That’s what mRNA does, it tells DNA what to make. So, the COVID mRNA tells the DNA in your muscle cell to make the harmless COVID piece and then your immune system goes to work.
mRNA vaccines are becoming very popular because they are easier to make and can be made quicker than normal vaccines. Also, some harmful bacteria and viruses have identical pieces, so one vaccine might be able to fight a lot of diseases. Last, mRNA has been used to fight cancer by telling the immune system to attack cancer cells.
The COVID vaccine was developed very quickly. Next, we will talk about how the scientists were able to develop the vaccine so fast.