https://techcrunch.com/2020/03/25/new-crowdsourced-covid-19-symptom-map-could-build-a-more-complete-pandemic-picture/

A new initiative by the Boston Children’s Hospital and Harvard Medical School could provide a new kind of signal for those studying the spread of the coronavirus pandemic across the U.S. The ‘Covid Near You’ map developed by researchers at both organizations, asks individuals to self-report any potential COVID-19 symptoms, as well as if they’ve taken a test, and then maps that activity on a rolling two week basis.

This isn’t a map of confirmed COVID-19 cases – other sources for that information already exist, including Google’s coronavirus map, which uses case numbers and figures provided by the World Health Organization (WHO), and the John Hopkins coronavirus resource center map. These are useful resources, but only reflect confirmed cases based on approved testing, which, especially in the U.S., is limited by testing availability and drastically under-represents the actual spread according to most experts.