Twitter allows millions of social media fans to comment in 140 characters or less on just about anything: an actor’s outlandish behavior, an earthquake’s tragic toll or the great taste of a grilled cheese sandwich.

But by sifting through this busy flood of banter, is it possible to also track important public health trends? Two Johns Hopkins University computer scientists would respond with a one-word tweet: “Yes!”

Mark Dredze and Michael J. Paul fed 2 billion public tweets posted between May 2009 and October 2010 into computers, then used software to filter out the 1.5 million messages that referred to health matters. Identities of the tweeters were not collected by Dredze, a researcher at the university’s Human Language Technology Center of Excellence and an assistant research professor of computer science, and Paul, a doctoral student.

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