[lowdanie]

1. One advantage of the mRNA vaccine is that each strand of mRNA is translated to protein many times before it is degraded. So less vaccine has to be manufactured and the dosage can be smaller. Another advantage is that since it lacks proteins you do not develop immunity to the vaccine itself, meaning that you can receive multiple booster doses.

2. Yes, the mRNA is ultimately degraded. But part of the process of developing the vaccine is fine tuning the precise rna sequence in order to achieve the desired half life.