As they say, "one and done!"
But, if enough of the idiots never get a Covid shot of some kind, the virus will evolve into one that will require a new shot. We can find ourselves in an infinite loop.
Alex
"There is a cult of ignorance in the United States, and there has always been. The strain of anti-intellectualism has been a constant thread winding its way through our political and cultural life, nurtured by the false notion that democracy means that "my ignorance is just as good as your knowledge."
-- Isaac Asimov