Google tracks flu activity online

As I type this, I'm coughing and wheezing from my first real cold of the season. This will continue, on and off, for the next four months or so. And then I'll get well, and then allergy season will be here.

Google recently launched an interesting microsite that lets interested parties track flu outbreaks from week to week and state to state. Google Flu Trends shows overall prevalence of flu compared to past years, and also offers a helpful map of the U.S. that breaks down outbreaks geographically. If I just moved one state over to Nevada, maybe I wouldn't be coughing up a lung.

How's Google do this? As with most of its tricks, it uses search data to estimate illness incidence, based largely on the number of people searching online for "flu" and related terms. More specifically (per Google's info page): "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."

Want to get this kind of information while you're away from your desk? Check out the Zicam Cold & Flu Companion, a similar type of application that's designed for Android and the T-Mobile G1. (The Zicam data comes not from web searches but from polls directed at doctors and pharmacies.) 

So there you have it. It isn't a live feed from the CDC, but it's a very close approximation and one that's a lot easier to update in real time. It's also one that indicates a whole lot of you are probably about to get sick in the next few weeks.

Incidentally, I'd love to see Google try to expand this to other diseases and even other seasonal/regional issues, like air quality, criminal activity, and even computer virus outbreaks, so we could more easily see how all these trends develop over time.