Weaponized Health Communication: Twitter Bots and Russian Trolls Amplify the Vaccine Debate

To understand how Twitter bots and trolls ("bots") promote online health content.We compared bots' to average users' rates of vaccine-relevant messages, which we collected online from July 2014 through September 2017. We estimated the likelihood that users were bots, comparing proportions of polarized and antivaccine tweets across user types. We conducted a content analysis of a Twitter hashtag associated with Russian troll activity.Compared...