Jeff Vandermeer said this quote

The idea that a dysfunctional thought could take root in a vacuum, the individual anonymous and wraithlike, unknowable because, especially at first, he or she had no interaction with other people. Because more and more in the modern Internet era you came across isolated instances of a mind virus or worm: brains that self-washed, bathed in received ideologies that came down from on high, ideologies that could remain dormant or hidden for years, silent as death until they struck. Almost anything could happen now, and did.