Legionnaires` disease: Seeking effective prevention

During the Bicentennial summer of 1976, American Legion Conventioneers in Philadelphia suffered a dramatic epidemic that left 34 dead. Near the end of 1976, scientists at the Centers for Disease Control (CDC) in Atlanta discovered the bacterium that caused Legionnaires` disease and named it Legionella. Nearly two decades later, a wealth of scientific information exists about the organism, its health effects, epidemiology, microbiology, aquatic ecology, molecular biology, immunology, pathophysiology, etc. Fortunately, for the engineer seeking to prevent Legionnaires` disease, it is unnecessary to master this complexity; the practice of prevention requires understanding a few, straightforward facts. The purpose of this paper is to present four messages about Legionnaires` disease that provide a conceptual framework to guide the crucial role of practical prevention. Those messages are: Legionnaires` disease is important; Legionnaires` disease is an environmental disease; Legionnaires` disease is preventable; and Legionnaires` disease prevention requires the right strategy.