I don't believe a vaccine to a virus that keeps having different dominant mutations quite often can ever be 100%, no matter if we are talking about Covid or not. I know cases where the flu vaccine coincided with one of the most severe flu episodes experienced (as the persons involved described it, and yes, it's more than one case, and I'm not a doctor to come in contact with patients every day).
Your belief seems to be correct. The mutations of a virus render a vaccine ineffective against that virus.
Thanks for stopping by.
!ALIVE
You Are Alive so I just staked 0.1 $ALIVE(6/10)@gadrian! to your account on behalf of @hafiz34.
The tip has been paid for by the We Are Alive Tribe
through the earnings on @alive.chat, feel free to swing by our daily chat any time you want.