A closer look
Going to a convention to swap war stories shouldn't end in an explosive mass casualty event. In 1976, an American Legion gathering in Philadelphia turned into a terrifying medical whodunit when dozens of attendees rapidly died of severe, bleeding pneumonia. The culprit wasn't a targeted biological weapon, but a previously undiscovered bacterium, Legionella pneumophila, which was happily multiplying in the hotel's aerosolized cooling towers and raining invisible death onto the lobby below.
