When people get sick, they often start looking online for information about their symptoms and illness. Sara Del Valle, a scientist and applied mathematician at Los Alamos National Laboratory, says that by training a computer model to analyze the specific health-related pages that users access on Wikipedia, public health experts may be able to identify—and even forecast—outbreaks of diseases such as influenza and Dengue fever. An article about the approach was published this week in the journal PLOS Computational Biology.