Google.org launched Google Flu Trends in time for last year’s flu season in the US. The underlying model was created by correlating the popularity of certain Google searches with subsequently available data about the incidence of flu at that time.

Having been validated, the model can provide near a real-time indication of flu levels. Google provides this information for the benefit of public health officials and individuals.

The countries now covered by Flu Trends are Australia, Austria, Belgium, Bulgaria, Canada, France, Germany, Hungary, Japan, Mexico, Netherlands, New Zealand, Norway, Poland, Russia, Spain, Sweden, Switzerland, Ukraine, and the United States.

Flu data used by Google comes from various sources, notably the European Influenza Surveillance Network of the European Centre for Disease Prevention and Control.

Google Flu Trends is showing an early start to the US flu season this year, with flu activity already being classified as high.