Social distancing data by region
Google is providing national and state social distancing reports on this site:
These reports are generated as PDFs. Deviations from location benchmarks and changing transmission rates should provide an impact estimate of how social distancing practices influence changing numbers of individuals testing positive for COVID-19.
This regional factor would impact the probability of a set of symptoms being indicative of COVID-19 versus some other infection.
Google is providing this information to health and government institutions - and I suspect access to this information can be found in a more easy to use format.