|Waterborne Pathogens of significance
Waterborne pathogens are contaminants in water that can cause illness or disease. The water we rely on for life can harbor bacteria, protozoa, and fungi that can cause illness when ingested, inhaled, or contacted. Even though our municipal water supplies are treated with primary disinfectants such as chlorine, there are other factors that can contribute to the growth and survival of pathogens in the water, including flow dynamics, temperature, metallurgy, and even the presence or absence of other bacteria or Protozoa.
This is why engineered water systems, such as domestic hot water systems, industrial cooling systems, and decorative fountains are of such a concern. Water used for daily activities such as showering, cleaning, cooling, and irrigating can present a hazard to the surrounding population, particularly to those with weakened immune systems.
In these types of engineered water systems, biofilms can form on the wetted surfaces. A biofilm is a thin layer of organic matter that creates a complex nutrient source and environment for bacteria and protozoa to survive. Biofilms can also isolate and protect bacteria from disinfectants. In biofilms, bacteria have a much higher resistance to antimicrobials than if they are free in the water. It is in these biofilms that many waterborne pathogens such as Legionella can grow and reproduce.