Donate to Science & Enterprise

S&E on Mastodon

S&E on LinkedIn

S&E on Flipboard

Please share Science & Enterprise

Anti-Vaccine Groups More Adept at Facebook Ads

Facebook screen

(Simon Steinberger, Pixabay)

15 Nov. 2019. A review of advertisements about vaccinations shows a few groups took advantage of Facebook’s advertising policies to spread vaccine misinformation. The review, appearing in the 13 November issue of the journal Vaccine (paid subscription required), also contends Facebook’s policies could limit pro-vaccine ads, while anti-vaccine messages may not be restricted by its rules.

Childhood vaccinations, once considered routine and non-controversial, became a source of debate in recent years as questions of vaccine safety arose from various groups. Despite repeated and voluminous scientific evidence of vaccine safety, questions continue to be raised by organizations, often repeated on social media. The result is what World Health Organization calls “vaccine hesitancy,” reluctance or refusal to vaccinate, despite the availability of vaccines.

WHO lists vaccine hesitancy as one of its top 10 health threats worldwide, with an increase in measles, for example, of 30 percent globally in recent years. Centers for Disease Control and Prevention says as of 7 November, 1,261 cases of measles are reported this year in the U.S., up from 372 cases reported last year, and only 55 cases in 2012.

Researchers led by public health professor Sandra Quinn at University of Maryland, engineering professor David Broniatowski at George Washington University, and Johns Hopkins University computer science professor Mark Dredze, are seeking to better understand Facebook’s role in spreading misinformation about childhood vaccines. Facebook is the world’s leading social network with more than 2.4 billion active users each month, according to Statista, and a major presence in the lives of many people worldwide. For its part, Facebook has taken steps beginning in March 2019 to block pages and hashtags that spread vaccine hoaxes.

The research team focused on paid advertisements on Facebook, and took advantage of Facebook opening up its advertising archive for exploration. That archive, now called its Ad Library, is searchable by Facebook members and non-members. The researchers focused on the period before March 2019, and searched Facebook’s ads with the keyword “vaccine” during December 2018 and February 2019. The search revealed 505 advertisements, which the team categorized as pro-vaccine, anti-vaccine, or not relevant. The researchers also analyzed themes expressed by the ads.

The team found 309 relevant ads, with the percentage of pro-vaccine ads (53%) edging out anti-vaccine ads (47%). However, the anti-vaccine ads were more focused and repetitive, which the researchers attributed to the smaller number of ad buyers. The search shows two organizations — World Mercury Project and Stop Mandatory Vaccinations, both funded by private individuals — buying more than half (54%) of the anti-vaccine ads, with most of those ads (55%) describing harmful outcomes of vaccines. At the time, ad buyers could target Facebook members expressing an interest in vaccine controversies, which its new rules no longer permit.

Pro-vaccine ads on Facebook, on the other hand, came from 83 different organizations. About half of the pro-vaccine ads (49%) expressed support for vaccinations in general, with about equal smaller percentages promoting pro-vaccine philanthropies (15%) and policies (14%).

The researchers say Facebook’s new policies may make it more difficult now for pro-vaccine ads, since Facebook considers these ads as political in nature because they address issues of national importance. Many anti-vaccine ads however, say the authors, are considered expressions of personal opinion, and can evade Facebook’s political restrictions.

Faculty research assistant at University of Maryland and first author Amelia Jamison says in a university statement, “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.”

More from Science & Enterprise:

*     *     *

Comments are closed.