In the 1980s, public health officials in Barcelona, Spain, began to notice a series of asthma outbreaks that resulted in unusually high numbers of emergency room visits. The cause of the occasional day-long asthma spikes remained a mystery to officials for nearly a decade, until finally they identified defective grain silos at the city’s busy port complex. The silos had an inadequate filtering system, and on days when soy beans were unloaded, allergen-laden dust from the beans escaped and caused widespread asthma attacks. Using an inhaler equipped with a GPS (Global Positioning System) patients took a puff from the inhaler and the GPS mechanism collected their precise location, as well as the time and date, and reported that information to a database. Public health officials were able to construct a real-time picture of where and when patients were suffering from attacks. When the silos were identified and taken out of use, the outbreaks stopped. The findings were recently presented at the Institute of Medicine at the Community Health Data Forum sponsored by the U.S. Department of Health and Human Services. To read an overview, please click here.