Legionella, is type of bacteria that can cause Legionnaires’ Disease (Legionellosis) or Pontiac fever. Legionella spreads through inhaling water droplets that contain the bacteria, which leads to lung infection. While Legionella naturally occurs in freshwater and is usually harmless, legionella buildup in man-made water systems can lead to health problems. When water is warm, slow-moving, or stagnant, it can become a breeding ground for legionella to grow. Potable water, especially in large buildings with complicated plumbing, hospitals, or hotels can be sources of Legionella exposure. Cooling towers, decorative fountains, and hot tubs can also act as avenues of spreading Legionella. People over the age of 50, smokers, people with chronic lung disease, or people with a weakened immune system are most vulnerable to contracting Legionnaires’ disease.

Legionella is an emerging contaminant currently on the EPA’s Candidate Contaminant List (CCL5), meaning it is not currently subject to national primary drinking water regulations but it is likely present in public water systems. In partnership with RI Department of Health, RI NEMO is working to develop a report on state-level work being done to identify potential areas of legionella growth and amplification within public water systems and within municipalities across the country. The report will highlight practices, needs, and recommendations from other states on addressing a legionella outbreak.

For more information on Legionella and Legionnaires’ Disease, visit the RI Department of Health webpage.