Epidemiology of flu, epidemiology of names
Each week, millions of Google users around the world search for health information online. As you might expect, there are more flu-related searches during flu season, more allergy-related searches during allergy season, and more sunburn-related searches during the summer.
Google labs compared these query counts with data from a surveillance system managed by the U.S. Centers for Disease Control and Prevention (CDC) and found that some search queries tend to be popular exactly when flu season is happening…
By counting how often we see these search queries, we can estimate how much flu is circulating in various regions of the United States.
"During the 2007-2008 flu season, an early version of Google Flu Trends was used to share results each week with the Epidemiology and Prevention Branch of the Influenza Division at CDC. Across each of the nine surveillance regions of the United States, we were able to accurately estimate current flu levels one to two weeks faster than published" CDC reports.
Google Flu Trends use Google query to study the epidemiology of a virus, that is, its distribution in a population (U.S. inhabitants). But one can also use Google queries to do just the same thing with cultural representations (it is exaclty what the sociologist Baptiste Coulmont had done with the distribution of the names in France).