[NeutralCrane]

> The issue is selective pressure. Yes, the virus will mutate. But under an mRNA vaccine, only the spike protein needs to mutate for the vaccine to be render useless. In other words: mutating the spike protein will give the virus access to very broad unimmunized population.

> Up to that it makes perfect sense to me and my limited evolutionary knowledge. I can't tell wether is right or wrong. But it makes sense.

The issue with this is that the spike protein has to mutate enough for vaccine induced immunity to fail to recognize it, but the spike protein is critical for the virus actually entering and infecting cells, and therefore there isn't a whole lot of mutating it can do while remaining functional.

On the other hand, there is some evidence that vaccines targeting more than just the spike protein (as well as natural immunity) may potentially be more at risk for the "antigenic sin" trap, in which the immune system fails to respond to mutated versions of a virus as well as it does to the original version it encountered.