https://techcrunch.com/2020/04/06/facebook-covid-19-survey-cmu/

Starting today, some U.S. Facebook users will see a new pop-up on the app asking them to fill-out a survey about COVID-19. The survey, from Carnegie Mellon University’s Delphi epidemiological research center, is one of many new symptom mapping projects that seek to anticipate where the next wave of the virus will hit as COVID-19 sweeps through populations the world over.

As if often the case in research, the challenge for these symptom mapping efforts is attracting a large enough sample of respondents to paint a statistically meaningful picture. Carnegie Mellon’s research effort will get a big leg up from Facebook, which may promote similar surveys in different parts of the world if this one goes well.