We have found a close relationship between how many people search for flu-related topics and how many people actually have flu symptoms. Of course, not every person who searches for “flu” is actually sick, but a pattern emerges when all the flu-related search queries from each state and region are added together.
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.
The data goes back to 2003 and has been cross-referenced with survey data from the Centers for Disease Control. While all of this may seem a bit “big brothery”, Google assures us that they don’t use personally identifiable information to create their flu estimates, “only aggregated search queries are used to provide Google Flu Trends”.
Taking into account the World Health Organization’s overview on influenza GFT starts to seem like a pretty damn good idea:
Influenza rapidly spreads around the world in seasonal epidemics and imposes a considerable economic burden in the form of hospital and other health care costs and lost productivity. In the United States of America, for example, recent estimates put the cost of influenza epidemics to the economy at $71-167 billion per year.
In case you haven’t noticed lately our economy is pretty effed up. If anonymous Google searches can help the CDC identify outbreaks up to two weeks faster and potentially prevent further spreading it seems as though the end may justify the means.