Shazam, the music identification app, has thousands of 5-10s long clips from public places. Can we figure out the rate of background coughing on these clips, by location?
Do we have public sound recording at places like grand central stations? Can airports do cough detection on their security footage?
Can google just listen for coughing sounds near phones and chart it?
What about the classic, publicly known ways that google does monitoring - searches for symptoms?
Can google do contact tracing by phone location? Are they already doing this and sharing it with the government?
I assume that intelligence agencies have asked their people on the ground to report basic statistical information - how many people in your office are coughing, how many people are not present, etc. Then using that, calculated spread.
The really big questions are about government stability. What will change in North Korea, Iran, or other countries which are targets for change?
Will there be a permanent increase in mask-wearing? close physical activities? Eating out in groups as a result of this? We may go closer to the world portrayed in some of Asimov's stories where people spend all their time alone except special occasions, and everyone has a fear of physical closeness.
Will there be more children born 9 months from January? Fewer? I would expect an increase in mask wearing that lasts for years.