Study Examines Spread of Vaccine Misinformation on Social Media

December 17, 2019

Recent outbreaks in the United States are a reason to be concerned about vaccine misinformation getting to the public through social media. 

A new study looked at how vaccine misinformation is spread on Facebook, showing that a small group of anti-vaccine advertisement buyers has successfully leveraged the platform to target audiences.   

The study, which was recently published in Vaccine, examined the role social media can play in spreading vaccine messages by investigating more than 500 vaccine-related ads archived in Facebook’s Ad Library, which became available to the public in late 2018.1

The researchers found that although the percentage of ads against vaccines (47%) were similar in number to those promoting vaccinations (53%), the anti-vaccine efforts were more organized and mainly came from 2 groups funded by private individuals, the World Mercury Project, and Stop Mandatory Vaccination.1

“The average person might think that this anti-vaccine movement is a grassroots effort led by parents, but what we see on Facebook is that there are a handful of well-connected, powerful people who are responsible for the majority of advertisements. These buyers are more organized than people think,” lead study Amelia Jamison, a faculty research assistant in the Maryland Center for Health Equity, said in a University of Maryland press release announcing the study’s results.2

Related: Survey Finds 45% of Americans Have Some Doubt About Vaccine Safety

The researchers found that those ads promoting vaccinations had more varied themes and often came from multiple funders.

The study was conducted jointly by researchers from the University of Maryland, the George Washington University, and Johns Hopkins University.

Even more concerning is that because Facebook categorizes vaccine ads as “political” some education messages promoting vaccines have actually been rejected and aren’t able to reach their intended audience, the researchers said.2

“By accepting the framing of vaccine opponents-that vaccination is a political topic, rather than a one on which there is widespread public agreement and scientific consensus-Facebook perpetuates the false idea that there is even a debate to be had,” said David Broniatowski, associate professor of engineering management and systems engineering at George Washington University.2

Broniatowski, who also served as a principal investigator of the study, believes this could lead to increased vaccine hesitancy.2

Researchers pointed to the recent outbreaks in the United States as a reason to be concerned about the messages getting to the public through social media.2

However, researchers acknowledged that the study was conducted with data before Facebook announced in March its new efforts to curb misinformation in vaccine-related ads.3

Facebook said it planned to find ads including misinformation about vaccinations and “reject” them. The social media giant also planned to reduce the rankings and Pages of group’s determined to be spreading misinformation from the News Feed and Search functions.3

Broniatowski voiced concerns that even with the new efforts, organized anti-vaccine ad buyers may find ways to get around the new restrictions.

“There is a whole set of ads that focus on themes of ‘freedom’ or ‘choice’ and that elude the Facebook rules around vaccine ads,” he said in the release.2

Researchers plan to continue their work to study how anti-vaccination messages are spread on Facebook, and try to determine whether efforts to curb the misleading information on Facebook has been effective.2

References:

1. Jamison AM, Broniatowski DA, Dredze M, et al. Vaccine-related advertising in the Facebook Ad Archive. Vaccine. 2019. Doi: https://doi.org/10.1016/j.vaccine.2019.10.066
2. Inoculating Against the Spread of Viral Misinformation [news release]. University of Maryland’s website. https://sph.umd.edu/news-item/inoculating-against-spread-viral-misinformation.
3. Facebook. Combatting Vaccine Misinformation. Facebook’s website. https://about.fb.com/news/2019/03/combatting-vaccine-misinformation/.