I am not sure why you think a virus wouldnt go after unvaccinated but it’s what happens. see the pandemic from years ago. Circulated many times. Killed more people in a later go around
Viruses don't "go after" anybody. They're in the environment and those who are susceptible will contract them. The current "vaccines" don't appear to effect much, if any, resistance to the delta variant, government propaganda notwithstanding.
Viruses don’t “go after” anyone. Viruses are in no way sentient beings.
Which earlier pandemic?