Facebook said Monday it will take more action against anti-vaccine misinformation posted on the network, focusing in particular on false claims regarding the coronavirus.

Beginning immediately, users, groups and pages that repeatedly spread known COVID-19 falsehoods, as detailed in an ever-expanding list, may see themselves banned from the platform.

Facebook added four categories to the list Monday, explicitly banning claims that COVID-19 is human-made or manufactured; that vaccines are not effective at preventing the disease they are meant to protect against; that it’s safer to get the disease than to get the vaccine; or that vaccines are toxic, dangerous or cause autism.

Previous efforts to stymie anti-vaccine content on the platform sought to reduce the content’s visibility, but stopped short of deleting it and banning those responsible for its spread.

A Facebook spokesperson told HuffPost the company wouldn’t disclose its enforcement thresholds, citing concerns about users gaming the system to avoid getting banned. Users who see their access restricted will be subject to an escalating series of enforcement actions before their accounts are disabled. 

The company also plans to tweak its search feature so users seeking out vaccine misinformation will instead be redirected to more “authoritative” results. On Instagram, which is owned by Facebook, anti-vaccine accounts should expect to be down-ranked “in the coming weeks,” the company said in a blog post.

“This is based on guidance from public health organizations that pervasive misinformation about COVID-19, and vaccines more broadly, is contributing to COVID-19 vaccine hesitancy that could have immediate and long-term physical health harms for people around the world,” the spokesperson said.

The action is the latest effort in a long-running struggle for the platform. Anti-vaccine conspiracies have run rampant on Facebook for years, even prompting Rep. Adam Schiff (D-Calif.) to press CEO Mark Zuckerberg on the issue in a February 2019 letter.

Despite having redoubled its efforts amid the COVID-19 pandemic, however, the social media behemoth has perpetually had to play catch-up and at times failed to enforce its own rules.

In October, Facebook earned praise after it banned ads “that discourage people from getting a vaccine.” Yet the site nevertheless continued to run anti-vaccination ads, including signing off on new ads, after the ban went into effect, only removing them after an inquiry from HuffPost.

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