The Delphi Blog

News, findings, and musings from the epidemic tracking and forecasting team.

COVID-19 Symptom Surveys through Facebook

Alex Reinhart and Ryan Tibshirani

Since April 2020, in collaboration with Facebook, partner universities, and public health officials, we’ve been conducting a massive daily survey to monitor the spread and impact of the COVID-19 pandemic in the United States. Our survey, advertised by Facebook, is taken by about 74,000 people each day. Respondents provide information about COVID-related symptoms, contacts, risk factors, and demographics, allowing us to examine county-level trends across the US. We believe that this combination of detail and scale has never before been available in a public health emergency. In this post, we’ll share some of our initial survey findings, show you how to access the data, and highlight some of the exciting new directions that we’re pursuing.


Hello World!

Roni Rosenfeld and Ryan Tibshirani

Hello from the Delphi research group at Carnegie Mellon University! We’re a group of faculty, students, and staff, based primarily out of CMU together with strong collaborators from other universities and industry. Our group was founded in 2012 to advance the theory and practice of epidemic forecasting. Since March 2020, we have refocused efforts towards helping combat the COVID-19 pandemic, by supporting informed decision-making at federal, state, and local levels of government and in the healthcare sector. Until now, we’ve been pretty “heads down” with our work, and slow to communicate what we’ve been up to. But at last … Delphi finally has a blog! This first post serves as an introduction of sorts. Future posts will dive deeper into our various projects.