Loss of smell is a Covid19 symptom. That's a test. Everyone should do that test

There is strong evidence that loss of sense of smell is a common (and peculiar) symptom of Covid-19. Partial information is worth something. Everyone in the world should be testing their sense of smell, at least daily, and we should be recording the results somewhere. Otherwise we are just throwing enormous amounts of information away.

At the moment it's just: "Some people who test positive report a loss of smell. That's interesting. Maybe we should look into it."