Drudge is reporting that Google plans on releasing a tool to the federal government that uses data gathered from web searches for flu related keywords to notify health agencies where an outbreak might be happening. Lets for a minute ignore the privacy implications of this project and think of the potential benefits of an early warning system that notices patterns as soon as people start getting the sniffles.
Google explains its methodology:
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.
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.
CDC uses a variety of methods to track influenza across the United States each year. One method relies on a network of more than 1500 doctors who see 16 million patients each year. The doctors keep track of the percentage of their patients who have an influenza-like illness, also known as an “ILI percentage”. CDC and state health departments collect and aggregate this data each week, providing a good indicator of overall flu activity across the United States.
So why bother with estimates from aggregated search queries? It turns out that traditional flu surveillance systems take 1-2 weeks to collect and release surveillance data, but Google search queries can be automatically counted very quickly. By making our flu estimates available each day, Google Flu Trends may provide an early-warning system for outbreaks of influenza.