When the flu bug bit the Big Apple, Twitter posts told the tale

Sifting flu-related tweets can help track the illness at the local level, not just on a national scale, researchers have found. The finding is important because key decisions on how to prepare for and treat a flurry of flu patients are made mostly in the cities and towns where the disease is spreading. An early alert can lead local health officials to boost efforts to vaccinate healthy residents to help contain the virus.