“Originally, anti-vaccine hysteria was a religious thing—using vaccines prevented people from getting sick, and thus went against God’s plan...”
I don’t remember that.
I don’t remember that.
That's probably because you weren't born yet.
As soon as Dr. Jenner developed the first smallpox vaccine, religious fanatics went all out to discredit him and to claim that vaccines go against God's plan. According to this website, religion-based anti-vaxxers were busy even before Dr. Jenner's seminal work.
Somewhere along the way, anti-vax morphed into a leftist cause-celebre. No matter who is the main push behind it, however, it results in more deaths from preventable disease. And that is never good.