People believe that most cases of Legionnaire’s disease, cause by Legionella bacteria, are associated to HVAC and/or cooling towers. This is false. In fact, The WHO reports that cooling towers only accounted for 28% of global reported Legionnaires’ disease cases. Other sources or Legionella contamination and Legionnaire’s disease outbreaks include potable water outlets, hot tubs, domestic plumbing systems such as those hound in healthcare, hotels and long term care facilities.