In the US,this went mainstream for the pandemic. It was an existing undercurrent in different communities.

Reactionary people weaponized vaccines with Gardasil - good Christian boys and girls are chaste until marriage, so vaccination is unnecessary. Sinners get gods punishment.

Crazy left-wing people cling to the autism rumors about vaccination.

All of this is magnified by politics and propaganda. Certain religious sects punch above their weight because of political factors - you can usually correlate this with measles outbreaks. Foreign influence operations encourage and stoke this stuff to encourage general unrest as well.