One of the biggest challenges in flattening the curve of the coronavirus and COVID-19 is information on where it is spreading and who has it or has had it. Social media, and more specifically Facebook and its 2 billion users, may be able to help.

Facebook is asking users to share some health information about symptoms they might have to track the spread of the virus across the country. That data is then shared with Carnegie Mellon University to build a symptom map. The first one was just released.

The map breaks down symptoms of the virus county-by-county. It will be updated daily and shows the percentage of people in those counties with symptoms of COVID-19.

Here's how they get the information: Every day a new sample of Facebook users will be asked to participate in a survey about any symptoms they have. Carnegie Mellon gets the data and builds the map.

The first map doesn't have a lot of data, because the surveys are only beginning. In fact, the first release shows many counties where there haven't been enough people answering the survey to determine an estimate.

That will change, of course, as the days go by and more people fill out the surveys. The data will be shared with health researchers to combat the disease.

So will it work? It depends on participation of Facebook users. Of course, many people do not trust Facebook with their data. Comments from users on Mark Zuckerberg's original​ post ​show many people suspicious of how their data will be used. But many other comments from users who think Facebook is doing an honorable service.

Zuckerberg and Carnie Mellon researchers promise not to share names or profiles.

But will that be enough to convince users to share their data on their health, and will they answer honestly? The success of the survey depends on it.