Google just announced a major expansion of its Flu Trends program which monitors searches for Flu-related symptoms on Google’s search engine to predict Flu outbreaks. Until now, Google only made the data it gathered from searches in the U.S., Mexico, Australia and New Zealand available, but now, Google has expanded the product to cover 16 more countries, including Russia, Norway, Sweden, Germany, France, Poland and Spain.

Flu Trends launched last November, and a lot of people were skeptical about whether Google’s data could really be used to track the spread of the flu. According to Google’s own research (PDF), which was published in Nature earlier this year, Flu Trends had a 0.92 correlation with the official flu data. Now, with the help of data from the European Centre for Disease Prevention and Control, Google was also able to validate its models for flu-related queries in Europe. The official data is usually a week or two behind, but Google’s data is created in real time.

Google has been very active in the Flu research community. Just a few weeks ago, the company also announced a partnership with the Public Library of Science, which now uses Google Knol to publish data and papers about influenza research.