Vaccines introduce your body to a weakened version of a germ so that if you are ever exposed to the real thing, your body is already prepared to fight it off (Mayo Clinic).
mRNA vaccines contain a specific, unique piece of the virus that causes COVID-19 virus called the spike protein. Our bodies recognize that this protein does not belong and develop antibodies to fight off this protein. If our immune system comes into contact with this protein again, our bodies remember how to fight this virus that causes COVID-19.
Researchers have been working with mRNA vaccines for decades now, and once enough information about the COVID-19 virus became available, scientists around the world began to apply past research towards developing a mRNA vaccine for COVID-19.
Each vaccine ingredient serves a specific purpose with the goal of providing long-lasting protection. Components of vaccines include preservatives, adjuvants, and stabilizers which work to keep the vaccine safe and optimize its use inside the body. These ingredients are also found in regular foods like fish and eggs.