For me, the characteristic that principally defines anti-vaxxers, isn’t their selfishness, as most of them genuinely believe they are doing the right thing; I t’s their supreme arrogance and stupidity.
They actually think they are better informed on the subject than the overwhelming majority of medical professionals (and by overwhelming, I would say over 95%) based on something they’ve read on the internet. And they are prepared to play cards with their lives off the back of it, with all the devastating consequences for those around them.
Arrogant, deluded, recalcitrant clowns.
It’s both comic and tragic in equal measure.