Every day, millions of people around the world type their health symptoms into Google. We can use these searches to help detect unknown Covid-19 outbreaks, particularly in parts of the world with poor testing infrastructure.
To see the potential information lying in plain sight in Google data, consider searches for “I can’t smell.” There is now strong evidence that anosmia, or loss of smell, is a symptom of Covid-19, with some estimates suggesting that 30-60 percent of people with the disease experience this symptom. In the United States, in the week ending this past Saturday, searches for “I can’t smell” were highest in New York, New Jersey, Louisiana, and Michigan — four of the states with the highest prevalence of Covid-19. In fact, searches related to loss of smell during this period almost perfectly matched state-level disease prevalence rates, as the accompanying chart shows....
https://www.nytimes.com/2020/04/05/opin ... rches.html
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