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. We compared our query counts with data from a surveillance system managed by the U.S. Centers for Disease Control and Prevention (CDC) and discovered 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.
It’ll be interesting to watch this year trend against previous years’ data- I’m going to be watching New York especially closely.
I also like that Google embeds a search panel on the page (via the American Lung Association) for finding the nearest place to get a flu shot.
Google will also let you download the historical data and/or the data for current estimates.
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