Marko Djurica / Reuters

Look up vaccinations on Facebook, as Representative Adam Schiff did last week, and the results will show a rich supply of anti-vaccination posts, pages, and groups. Such propaganda appears to be flourishing online, drawing the uninitiated into a tangled web of sources through algorithmic recommendations and human shares.

Facebook, for its part, laments the reach of such “health-related misinformation.” But the company can also use the presumed complexity for cover. If the anti-vaccination posts are widely distributed, then fixing this misinformation problem becomes massively more difficult. Imagine that hundreds of thousands of people are responsible for the anti-vaccine chatter: To take action against such a network could cause huge ripples in the makeup of the network. Sensitive to cries of censorship, Facebook would shy away from intervening.

However, while Facebook’s scale might as well be infinite, the actual universe of people arguing about vaccinations is limited and knowable. Using the web-monitoring tool CrowdTangle, I analyzed the most popular posts since 2016 that contain the word vaccine. I found that a relatively small network of pages creates most of the anti-vaccine content that is widely shared. At the same time, a small network of “pro-science” pages also experiences viral success countering the anti-vax posts.

While there is no dearth of posts related to vaccines, the top 50 Facebook pages ranked by the number of public posts they made about vaccines generated nearly half (46 percent) of the top 10,000 posts for or against vaccinations, as well as 38 percent of the total likes on those posts, from January 2016 to February of this year. The distribution is heavy on the top, particularly for the anti-vax position. Just seven anti-vax pages generated nearly 20 percent of the top 10,000 vaccination posts in this time period: Natural News, Dr. Tenpenny on Vaccines and Current Events, Stop Mandatory Vaccination, March Against Monsanto, J. B. Handley, Erin at Health Nut News, and Revolution for Choice.

Despite panic in cases such as the current measles outbreak in the United States, anti-vaccination activism most likely has been substantially less influential than it sometimes appears to be. As Slate’s Daniel Engber has pointed out, U.S. vaccination rates for measles, for example, have barely budged in recent years: It was 91.5 percent in 2005, and again in 2010, and again in 2014, and again in 2017. What has changed is the (social) media ecosystem. Even if the bulk of Americans aren’t changing their behavior, anti-vaccine talking points are more widely available thanks to the concentration of social activity on a few platforms and the substantial reach of a small number of anti-vax media organs.

Mainstream media outlets and specialty outlets find success in running debunkings of these anti-vax claims. The appearance of a debate generates factional attention, driving the us-versus-them shareability of posts on all sides. Not unlike conservative news outlets that relentlessly cover the Democratic Representative Alexandria Ocasio-Cortez for clicks, “pro-science” pages such as I Fucking Love Science, SciBabe, and The Credible Hulk can attract readers on Facebook by tickling the someone-is-wrong-on-the-internet gland of audiences who already agree about vaccination.

This is not at all to say the sides’ evidence or goals are equivalent. One is spreading misinformation, often to sell a product or service, while the other relies on credible scientific evidence to protect a public-health achievement. But each circuit plays a part in expanding the bubble of attention to the anti-vax position, even though most people don’t buy it.

The crucial factor is the huge audience that just a few social-media platforms have gathered and made targetable through regular posts as well as advertisements. Pinterest recently stopped showing search results for vaccine searches. YouTube told me in a statement that it was “surfacing more authoritative content across our site for people searching for vaccination-related topics, beginning to reduce recommendations of certain anti-vaccination videos and showing information panels with more sources where they can fact check information for themselves.”

As the other platforms make moves to slow and counter health conspiracies on their sites, Facebook has also been circling the problem. “We’ve taken steps to reduce the distribution of health-related misinformation on Facebook, but we know we have more to do,” a spokesperson told me. “We’re currently working on additional changes that we’ll be announcing soon.” While Facebook has been loath to actually delete pages, it could downrank them or even leave them completely out of searches for vaccine information. Right now, it remains unclear exactly what steps Facebook has taken or will take in the near future.

With any current changes and prospective ones, the company will not be moving against inert entities. Given that my CrowdTangle analysis points out that anti-vaccine propaganda is so concentrated on Facebook among a small, interconnected group, the important nodes in that network have been preparing, rhetorically and operationally, for the Facebook maneuvers. But such concentration means that shutting down just a few pages could make a difference.

Among the most prominent anti-vax pages is Natural News, an Infowars-like conspiracy site sprinkled with tumeric powder and the essence of chemtrails. The site, which has 2.9 million likes and comes up high in a variety of search results about vaccines and vaccination, runs stories with headlines like “Left-Wing Media Run by Actual Demon-Possessed Anti-human EVIL Entities … Watch This Stunning Mini-documentary” as well as “Tech Giants’ Censorship Is an Online ETHNIC CLEANSING Campaign, Equivalent to Intellectual Genocide.” According to a list of the site's popular stories, the two most popular posts are both about vaccines.

Natural News has kept up a steady drumbeat of posts about how the site is going to be “silenced” or “censored” by the tech platforms. The site’s owner, Mike Adams, has claimed that Apple (among other tech companies) is defending “satanism” by asking Natural News to make changes to its app in the App Store. “This is the first time that a dominant tech company has overtly come out in defense of Satanism while threatening to censor a prominent publisher that exposes the evils of Satanic influence,” Adams wrote in a recent post. He refers to the tech companies as “techno-fascists.”(Natural News did not respond to a request for comment.)

But many of the most popular anti-vaccine pages are much less overtly conspiratorial in nature. Dr. Tenpenny on Vaccines and Current Events stars a very reasonable-seeming doctor from Middleburg Heights, Ohio. Sherri Tenpenny has an integrative-medicine practice in Ohio, but has also begun offerring an eight-week “Mastering Vaccine Info” boot camp for $595. The course lays out the anti-vax perspective on history, and “most importantly, you will learn the necessary language skills to communicate key concepts in sound bites, to confront bullies and how to stand your ground.” (Tenpenny did not respond to a request for comment.)

If the pages structured around anti-vaccine misinformation are easy to see for what they are, other pages present a more complicated picture. They are not filled with rants about satanism, and they’re painted with the soft colors of a parenting site. Take Erin at Health Nut News. Most of the posts on the page are related to general wellness and other health news. But some of them follow the softer anti-vaccination line, arguing against “mandatory vaccination” and for “parental choice,” among other things. On the Health Nut News website, you can buy chi-balancing tools, CBD oils, and tea that “unleashes your body’s potential.”

The proprietor of the page, Erin Elizabeth, posted this week that “FB is Thinking of deleting or censoring pages that talk about alternative/natural health,” while encouraging her followers to like her personal page, as it would “hopefully” stay on Facebook. She also encouraged users to subscribe to her email list, “as we may disappear with censorship.” (Elizabeth did not respond to a request for comment.)

As the anti-vax pages try to herd their audiences off Facebook or into private groups, the platform will have to steel itself for pushback. But anti-vax activism and opportunism do not map neatly onto the left-right political spectrum, which could make it easier for Facebook or YouTube to move against these pages. These activists portray their activity as an exercise of “free speech,” even if, legally, that is not the case.

Since the posts about and attention generated by vaccines are highly concentrated, Facebook should be able to greatly diminish these posts’ impact on the platform if it really is serious about anti-vax misinformation. At the same time, if Facebook begins to get serious about health misinformation, then it might have to deal with the profusion of scientifically dubious or outright ineffective medicines promoted by the likes of more mainstream sites such as Goop.

But hey, first things first.

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