One more cool service from google;
The official Google Blog introduced Google Flu Trends, an interesting tool that might change the way infectious diseases are monitored these days. It say"
Our team found that certain aggregated search queries tend to be very common during flu season each year. We compared these aggregated queries against data provided by the U.S. Centers for Disease Control and Prevention (CDC), and we found that there's a very close relationship between the frequency of these search queries and the number of people who are experiencing flu-like symptoms each week. As a result, if we tally each day's flu-related search queries, we can estimate how many people have a flu-like illness. Based on this discovery, we have launched Google Flu Trends, where you can find up-to-date influenza-related activity estimates for each of the 50 states in the U.S. flu trends, google flu trends, google flu, flu trend, flu

The CDC does a great job of surveying real doctors and patients to accurately track the flu, so why bother with estimates from aggregated search queries? It turns out that traditional flu surveillance systems take 1-2 weeks to collect and release surveillance data, but Google search queries can be automatically counted very quickly. By making our flu estimates available each day, Google Flu Trends may provide an early-warning system for outbreaks of influenza."

What is the flu?http://www.google.org/images/logo_tiny.gif

Influenza (the flu) is a serious contagious respiratory illness caused by influenza viruses. Millions of people in the United States get the flu each year. Most people are sick for about a week. Some people (especially young children, pregnant women, older people, and people with chronic health problems) can get very sick and may die from the flu.

How does this work?

We've found that certain search terms are good indicators of flu activity. Google Flu Trends uses aggregated Google search data to estimate flu activity in your state up to two weeks faster than traditional flu surveillance systems.

What information is provided by Google Flu Trends?
We provide up-to-date estimates of flu activity in the United States based on aggregated search queries. Data can be viewed on the Flu Trends website or downloaded as a CSV file for analysis.
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