Moderna Inc's COVID-19 vaccine for emergency use on Friday, a week after granting the first U.S. authorization to Pfizer Inc and BioNTech SE's coronavirus shot.The following is a comparison of the two vaccines and what to expect as both become available:How are the two vaccines similar? Both vaccines use messenger RNA (mRNA) technology, which contains instructions for human cells to make proteins that mimic part of the coronavirus.
The instructions spur the immune system into action, turning the body into a virus-zapping vaccine factory. No actual virus is contained in the vaccines.Both the Pfizer/BioNTech and Moderna vaccines target the crown-like spikes on the surface of the coronavirus that it uses to break into healthy human cells.