Google Flu Trends is a new Web tool that Google.org, the company’s philanthropic unit, unveiled on Tuesday, just as flu season was getting under way in the United States.

The N.Y. Times reports that Google Flu Trends is based on the simple idea that people who are feeling sick will probably turn to the Web for information, typing things like “flu symptoms” or “muscle aches” into Google. The service tracks such queries and charts their ebb and flow, broken down by regions and states.

Early tests suggest that the service may be able to detect regional outbreaks of the flu a week to 10 days before they are reported by the Centers for Disease Control and Prevention.

We’ve thought of doing something like this with surveillance of foodborne illnesss, or even restaurant inspection and complaints. But we don’t have the resources of Google.

Google Flu Trends (www.google.org/flutrends) is the latest indication that the words typed into search engines like Google can be used to track the collective interests and concerns of millions of people, and even to forecast the future.