Vaccine battle involves bots

Tweets were aimed at sowing division

Public health experts are up against Russian trolls and Twitter bots.

WASHINGTON — Public health experts battling dangerous misinformation about the safety of vaccines have a new foe: Twitter bots and Russian trolls.

Researchers found that bots and Russian trolls mentioned vaccines more often than the average Twitter account over a three-year period, but for different reasons.

Russian trolls stoked the debate by tweeting proand anti-vaccine messages in an apparent attempt to sow division, while bots that spread malicious software appeared to use antivaccine messages that inflame strong responses from both sides to attract clicks.

“Apparently only the elite get ‘clean’ #vaccines. And what do we, normal ppl, get?! #VaccinateUS,” a Russian troll account tweeted, in one of the messages that stood out to researchers because of the unusual line it drew between vaccine fearmongering and income inequality.

“That’s not something you see from an antivaxxer,” said David Broniatowski, an engineer at George Washington University who led the research published in the American Journal of Public Health. “Elites getting clean vaccines — we thought that was very unique to the Russian trolls, and could be interpreted as an attempt to link vaccination to a specific division within American society.”

The trolls were users connected to a Russian propaganda effort run by the Internet Research Agency, a troll farm. They were identified by the researchers through a list released by Twitter to Congress that was further refined by NBC.

Twitter bots were identified trough bot repositories and spanned a wide gamut, from spambots that are clearly non-human to “content polluters” that spread malware or try to scam people.

From 2014 to 2017, Twitter accounts that have been identified as Russian trolls were 22 times more likely to tweet about vaccines than the average user.

The tweets fell on both sides of the vaccine debate and appeared aimed at sowing discord by amplifying the debate — even though the vast majority of Americans believe vaccines’ benefits outweigh their risks.

These trolls may be flitting between divisive topics. Renee DiResta, who studies computational propaganda with the grassroots collective Data for Democracy, said that her own research suggests that Russian trolls have fixated on the vaccine debate not to seed a public health crisis, but to exploit its divisiveness.

“It’s opportunism — opportunistically amplifying controversial topics,” DiResta said.

In response to the study, Twitter pointed to a blog post that described its efforts to create tools that can identify “spammy or automated accounts automatically.”

In May, the company said it challenged more than 9.9 million such accounts per week.