Like fake photos, these will be most highly leveraged among the undereducated. Websites like Snopes will probably help serve as an outside point of reference in many cases; however some people are not really open to criticism of whatever is their current mental model and can just as easily see another point of reference as opposition propaganda as reliable analysis. Alex Jones is an example of one with this psychology--he has such a strong trust in his original sensory-experience-analysis-system that you're better off taking other approaches than making a frontal assault on the citadel of this subjective information-interpretation experience, which is so highly knotted up with his sense of self and personal creativity.

Fortunately this kind of lopsided/over-weighted psychological subsystem will never speak to everyone, and humans are as a group becoming more resilient in the face of such imbalance. The internet has in many ways been extremely helpful in serving as a sort of blowoff valve for psychological gifts that have spun out of balance.