Churning through, tabulating, and modeling millions of search queries every day, Google Flu Trends can measure, a full two weeks before the CDC, the incidence of influenza-like illnesses (ILI) across the U.S. Any official response to a flu pandemic, such as vaccine distribution and timing, could be greatly enhanced with such an early warning. And while not billed as an ersatz measure, Google Flu has had an uncannily high correlation with the CDC’s own slower, yet more assiduously produced estimate of ILIs.