Obligatory fuck /u/Spez.
This type of behavior needs to be regulated. Foreign interference isn't acceptable, and if Canada passes the online harms act then the ensuing regulator needs to handle situations like this or at least hand out massive fines for greed and indifference.
Fear.
Fear of losing bodily autonomy and control to mandatory vaccines, fear of government overreach (easy boogeyman to paint), but most of all, fear of unknown things they don't understand (microbiology and immunology).
Too bad they will have to relearn the fear of losing their children to a formerly eradicated disease.
Of course, the bastards with a financial incentive to profit from any patsy that falls for it also perpetuate this cycle of fear and loathing.