Assessing Risk of Legionella PDF

Legionella is the causative agent of legionellosis and can be isolated from environments such as rivers, streams, lakes, and man-made water systems. Legionella concentrations generally are highest on surfaces where biofilm is present and protozoa serve as hosts for replication. To become infected with Legionella, a susceptible individual must inhale or aspirate aerosols (generally less than 10 µm in size) containing sufficient numbers of virulent Legionella cells.