Facebook has a problem with more than just fake news. Add vaccine misinformation on the social network to the list.

Revealed Thursday: The social network says it will reduce distribution and provide users with "authoritative information" on the topic. Facebook is following the lead of Pinterest, which has blocked all searches using terms related to vaccines or vaccinations as part of a plan to stop the spread of misinformation related to anti-vaxx posts.

In mid-February, Facebook told USA TODAY it had "taken steps" to reduce fake health news and anti-vaxx posts and said it was considering making anti-vaccination content on its site less visible amid a measles outbreak that has reignited a conversation about preventative shots.

At the time, Facebook said, "we know we have more to do."

Facebook has been fighting misinformation on its platform since the 2016 presidential election after fake accounts and news stories aimed at sowing discord among users were discovered.

Social media sites have grappled with how to handle anti-vaxx posts from users amid a measles outbreak in Washington state affecting more than 60 people.

Facebook announced a series of new steps:

—It will reduce the ranking of Facebook groups and Pages that spread misinformation about vaccinations in News Feed and Search. "These groups and Pages will not be included in recommendations or in predictions when you type into Search," Facebook said.

—When it discovers ads with misinformation about vaccinations, "we will reject them."

—Facebook said it has removed related targeting options, like “vaccine controversies," in ads. "For ad accounts that continue to violate our policies, we may take further action, such as disabling the ad account."

Additionally, Facebook said it wouldn't show or recommend content that contains misinformation about vaccinations on the Explore section of Facebook-owned Instagram or on its hashtag pages.

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Facebook noted that global health organizations like the World Health Organization and the U.S. Centers for Disease Control and Prevention have publicly identified verifiable vaccine hoaxes. "If these vaccine hoaxes appear on Facebook, we will take action against them," Facebook said.



"We also believe in providing people with additional context so they can decide whether to read, share, or engage in conversations about information they see on Facebook," the company said. "We are exploring ways to give people more accurate information from expert organizations about vaccines at the top of results for related searches, on Pages discussing the topic, and on invitations to join groups about the topic. We will have an update on this soon."



Follow USA TODAY's Jefferson Graham on Twitter, @jeffersongraham