Survival of the Legionnaires' disease bacterium in water.

Data from this study indicate that the Legionniares' disease bacterium can survive for a relatively long period of time in water. Four strains survived in distilled water for 69 to 139 d and for 364 to 369 d in tap water. Viable cells from two strains were recovered from tap water at 408 to 415 d. There were no surviving bacteria in cooling-tower water after 24 to 48 h. The rapid die-off was probably due to bactericidal agents added to the water to control growth.