article at the New York Times examines this new outbreak tracker.
In early February, for example, the C.D.C. reported that the flu cases had recently spiked in the mid-Atlantic states. But Google says its search data show a spike in queries about flu symptoms two weeks before that report was released. Its new service at google.org/flutrends analyzes those searches as they come in, creating graphs and maps of the country that, ideally, will show where the flu is spreading.
This system people in the area to know a full week to ten days lead over flu outbreaks reported by the CDC, because reports of these come from visits to hospitals and doctors, which results in a lag time in information gathering. This is a system that can show the results of the intentions of humans.