https://www.siliconvalley.com/2020/04/20/coronavirus-new-facebook-map-tracks-those-reporting-symptoms-in-local-counties/

Facebook on Monday debuted a new interactive map that tracks coronavirus cases on a county-by-county basis, and which the social network says will be updated daily as part of the effort to help local officialS allocate their treatment resources.

The map includes data from a survey of more than 1 million Facebook users conducted by Carnegie Mellon University, and allows users to highlight individual counties to see what percentage of residents have reported coronavirus symptoms. In a Facebook post, Chief Executive Mark Zuckerberg said that researchers believe symptom survey maps like Facbook’s can serve as a tool for determining how best to distribute resources for healthcare professionals and governmental officials in their COVID-19 treatment efforts.