META Meta Platforms Inc

By Robert McMillan and Brianna Abbott 

Facebook Inc. said Thursday it would make it tougher for vaccine skeptics to spread misinformation, amid criticism that the tech giant wasn't doing enough to limit the proliferation of such content.

The company's move follows similar efforts from other social-media firms, and rising interest from lawmakers about how best to tackle this issue. On Tuesday, an Ohio teenager testified before Congress that his mother believes the false claim that vaccines cause autism because of what she read on Facebook. Ethan Lindenberger, 18 years old, said he got vaccinated against his mother's wishes.

In its crackdown, Facebook will ban adds that include misinformation about vaccines and will tweak its algorithms so pages that spread this type of content are no longer recommended. It will also downgrade those pages in the platform's news feed and search results so they don't spread as easily.

The effort is expected to start Thursday, but it will take several weeks to take full effect. It will also extend to Instagram, where the company will stop displaying antivaccine messages on its Instagram Explore and hashtag pages.

Vaccine misinformation has become a new battleground as technology companies grapple with the question of how and when to police content on their platforms. Last month, Pinterest Inc. said it had temporarily blocked searches for vaccine-related content on its visual discovery platform. YouTube, owned by Alphabet Inc., has also promised to crack down on this type of content.

Tech companies have also battled terrorism-recruitment campaigns, hate speech and sexual harassment -- moves that have opened them up to complaints of censorship and political bias. Critics say the content-moderation process on these platforms is often opaque and arbitrary.

Like Pinterest, Facebook says it will rely on information from the World Health Organization and the U.S. Centers for Disease Control and Prevention to determine the validity of vaccine information. The company is also exploring new ways of presenting its users with scientifically backed information whenever it encounters vaccine misinformation on its platforms.

As part of the changes, Facebook has already removed a controversial advertising option that let advertisers target users who were interested in "vaccine controversies."

"We are fully committed to the safety of our community and will continue to expand on this work," said Monika Bickert, Facebook's vice president of global policy management.

On Wednesday, Facebook pledged to provide end-to-end encryption technology to all its instant-messaging clients. The company said it was too early to speculate on how it might police vaccine misinformation on these messaging platforms, whose content isn't visible to Facebook, but said that it was committed to safety. Facebook has already limited users' ability to forward messages on its encrypted WhatsApp platform, in a bid to spread misinformation from going viral.

Concerns about vaccination date back decades, but antivaccine messages have mushroomed in the internet era, said Jonathan Jarry, a science communicator with the Office for Science and Society at McGill University, which tracks scientific misinformation. Social-media messages are particularly adept at tapping into messages of fear. "The misinformation works in part because it can be very easy to find," Mr. Jarry said.

Public backlash against the antivaccine movement has resurfaced in the past several months, due to measles outbreaks in areas or communities across the U.S. with low vaccination rates. Lawmakers in several states have recently introduced legislation to bar personal and religious exemptions for vaccinations.

A study published in the Annals of Internal Medicine on Tuesday found no link between the measles, mumps, rubella vaccine and autism, confirming previous scientific research. This study followed more than 600,000 Danish children born between 1999 and 2010 from one year of age until August 2013.

Measles was officially declared eliminated in the U.S. in 2000, but incidences have increased in recent years with a rise in state-sanctioned exemptions, which allow parents to have their children opt out of vaccinations for personal and religious reasons. There have been 206 confirmed cases of measles in the U.S. across 11 states since Jan. 1, according to the CDC.

Write to Robert McMillan at Robert.Mcmillan@wsj.com

(END) Dow Jones Newswires

March 07, 2019 15:54 ET (20:54 GMT)

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