As the coronavirus sweeps across the globe, vast numbers of people are looking for information about the disease. And as the most popular social media platform on the planet, perhaps it’s not surprising that a staggering number are turning to Facebook (FB) to find out.

In fact according to company COO Sheryl Sandberg, almost a billion people have looked on Facebook for information about COVID-19.

And Sandberg says, the social media giant has been working hard to fight misinformation about the disease, as well provide accurate information.

Battling false information has been difficult for Facebook, Sandberg acknowledges. But in a recent interview with me, she says the company is making progress.

“This has been a rough phase for Facebook. It's been years of really figuring out how we get ahead of things like misinformation, and we've made massive investments,” she told me. “We've learned a lot. And I think those lessons and those investments are really serving us well right now.”

Facebook has been trying to reduce the amount of fake news and misinformation on its platforms when it comes to elections, the census and now the coronavirus, the latter being a priority right now.

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“We don't want any misinformation that leads to imminent harm on our platforms. And we know we're not the experts,” she said. “So right at the beginning of this, we went to the WHO, the CDC and health ministries and said, ‘Please help us you tell us what are the facts that cause imminent harm that you want down and we're going to get to everything we can to take them down.’”

Sandberg says Facebook is using AI, machine learning tools and human review to remove misinformation about COVID-19 ASAP.

“We search for key phrases, we search for keywords, and we take down posts that could lead that to imminent harm,” she told me.

“We're also trying to proactively push the messages [health experts] want out,” she added. “The WHO asked us to get a hand washing video out now. Kind of sounds small, but it's not. Because now that I saw it, and I did what they asked me to, and I did: washing your hands the way they want you to really protect yourself against the virus. I didn't understand what that was. That is, 50 seconds, 40 seconds to 60 seconds of very vigorous rubbing. But that can save lives.”

“So we are both trying to take down the stuff that can cause harm, but really get out the stuff that can lead to some good and some prevention,” she said.

Facebook has also created a Covid-19 hub, which has a new Community Help feature.