Facebook found that a vast amount of its anti-vaxx content comes from a hard core of only 111 accounts

Facebook in a report obtained by The Washington Post identified key vaccine skepticism influencers.

111 accounts were behind half of all material doubting vaccines shared by vaccine hesitant users, it found.

Facebook is under pressure to counter the spread of vaccine misinformation.

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Facebook has identified a core of 111 accounts sharing a large amount of the anti-vaccine and vaccine skeptical material on its platform, according to an internal report obtained by The Washington Post.

The accounts in question were not named. According to the Post, Facebook identified them by carving up its US users into different categories and assessing how receptive they were to content skeptical of vaccines.

The 111 accounts were those responsible for most of the content consumed by the ten categories most receptive to such content overall, which the Post said accounts for more than 50% of vaccine-skeptic content on the platform.

Facebook bans posts about vaccines containing information that is provably false, but a large gray area exists of posts which undermine vaccines without saying anything demonstrably untrue.

There was significant overlap, according to the report, between those pushing anti-vaccination content and support for the QAnon conspiracy movement.

Facebook has come under pressure to clamp down on anti-vaccine content promoted and shared on its platforms amid the rollout of COVID-19 vaccines.

A report by activist group Avaaz last August found that health misinformation on the platform had been viewed more than 3.8 billion times in the past year, peaking as the pandemic hit.

Facebook on Monday announced new measures to help people access information about how to get vaccinated.

Anti-vaccine content is spreading more quickly on Instagram Insider reported in December 2020. The sites operate separate enforcement policies.

Instagram removed the account of prominent anti-vaccination activist Robert F Kennedy Jr in February, though his Facebook account remains active.

Experts told Insider at the time that the site's December policy change did not go far enough, and called on the site to expel prominent anti-vaccination activists.

The report shared with the Post did not identify the 111 accounts sharing most vaccine misinformation. Last year, the UK's Center for Countering Digital Hate in a report identified the most influential groups and individuals behind the movement.

A spokesperson for Facebook told the Post that it could use the data to change its policies around vaccine content, though no decisions had been made.