Check out Dr.

Check out Dr. Robin Dunbar's talk on Social Networks (SN) shared over here. How is it relevant to Fake news? When Social network size increases, news spreads faster than ever before. Moreover, SN analysis suggests active players/bots spread the news faster. It is similar to an epidemic/pandemic/disease spreading in a region.
http://www.srikanthkidambi.com/home/research-overview/facebook-or-privatebook