Refer to below link for CMS memo dated 6/2/2017

Legionella Infections: The bacterium Legionella can cause a serious type of pneumonia called LD in persons at risk.
Those at risk include persons who are at least 50 years old, smokers, or those with underlying medical conditions such as chronic lung disease or immunosuppression.
Outbreaks have been linked to poorly maintained water systems in buildings with large or complex water systems including hospitals and long-term care facilities.
Transmission can occur via aerosols from devices such as showerheads, cooling towers, hot tubs, and decorative fountains.
Facility Requirements to Prevent Legionella Infections: Facilities must develop and adhere to policies and procedures that inhibit microbial growth in building water systems that reduce the risk of growth and spread of legionella and other opportunistic pathogens in water.