Earlier this year, we asked a global group of public health officials and influenza experts how we can make Google Flu Trends better. Their most common request was for visualizations that enable easy comparison of flu levels across regions, so that differences in the trend of the season could be easily identified. We now publish the flu levels of all countries and regions on Google Public Data Explorer which provides this feature and much more. Also, as part of our annual model update for the Northern Hemisphere, we’re refreshing our models in 13 countries and adding new regional estimates for the Netherlands, Belgium, Canada, Switzerland, and Spain.
It’s important to note that the flu level is a normalized number indicating how unusually high or low our estimate of flu-related activity is in a place. Zero means business as usual. Eight means flu activity is unusually high for that country or region. So, you can’t use these visualizations to say there was more flu in one place than in another, but you can know whether the situation deviated more from normalcy in one location than in another.
Let’s look at some of the ways these new visualizations allow us to compare flu activity across the globe:
Has the flu season started in Western Europe? There was a bit of activity in Germany and Austria at the beginning of October. Otherwise, there is not much flu in that region as of this week.
Let’s look at the data on a map. On the chart below, each bubble has a size proportional to the flu level for November 9, 2008 (a minus sign indicates less flu activity than is usual). The flu season hasn’t started anywhere. Hit the “Play” button to see how the flu season develops first in the Northern hemisphere.
Check out how flu seasons alternate between the northern and southern hemispheres.
Click on "Explore data" in any one of the charts above to go to Public Data Explorer and start exploring!