(CNN) -- If you have a fever, headache and runny nose, you might go to Google and type the words "flu symptoms" to see whether you've come down with influenza.
Google's new public health initiative, Google Flu Trends, looks at the relative popularity of a slew of flu-related search terms to determine where in the U.S. flu outbreaks may be occurring.
"What's exciting about Flu Trends is that it lets anybody -- epidemiologists, health officials, moms with sick children -- learn about the current flu activity level in their own state based on data that's coming in this week," said Jeremy Ginsberg, the lead engineer who developed the site.
The tool, which launched Tuesday, operates on the idea that there's likely to be a flu outbreak in states where flu-related search terms are currently popular. Watch CNN.com's Elizabeth Landau explain how Google Flu Trends works »
The Centers for Disease Control and Prevention collaborated with Google on the project, helping validate and refine the model, and has provided flu tracking data over a five-year period, said Dr. Joseph Bresee, chief of the epidemiology and prevention branch in the CDC's influenza division.