Legionella, an enemy not to be underestimated.
What is Legionella?
Legionella is a genus of bacteria that proliferate in water, favoured by the presence of biofilm, stagnation, and critical temperatures. They are found in both natural environments and, more significantly, in artificial systems, where the risk of contagion is higher.
Legionella is an opportunistic pathogen responsible for both flu-like forms (Pontiac fever) with a benign course and the so-called Legionnaires’ Disease, a pneumonia with severe symptoms, with a fatality rate reaching 10-15%.
Its danger is recognised by the World Health Organization (WHO) and the Ministry of Health, which have drafted specific guidelines for the correct prevention and control of Legionellosis risk.
What is Legionella?
Legionella is a genus of bacteria that proliferate in water, favoured by the presence of biofilm, stagnation, and critical temperatures. They are found in both natural environments and, more significantly, in artificial systems, where the risk of contagion is higher.
Legionella is an opportunistic pathogen responsible for both flu-like forms (Pontiac fever) with a benign course and the so-called Legionnaires’ Disease, a pneumonia with severe symptoms, with a fatality rate reaching 10-15%.
Its danger is recognised by the World Health Organization (WHO) and the Ministry of Health, which have drafted specific guidelines for the correct prevention and control of Legionellosis risk.
In which environments is Legionella present?
Legionella prefers humid and temperate environments. It is ubiquitous in aquatic environments, both natural and artificial. Its proliferation is favoured by temperatures between 25°C and 50°C and in the presence of water stagnation, limestone or rust deposits, and biofilm. For this reason, water distribution systems, cold and hot sanitary water, showers and sinks, whirlpool baths, fountains, irrigation and misting systems, cooling towers, and industrial water circuits represent potentially at-risk contexts.
In which structures could Legionella be present?
Legionella can be present in any structure or building equipped with water distribution systems, cold and hot sanitary water, showers and sinks, whirlpool baths, fountains, irrigation and misting systems, cooling towers, and industrial water circuits. Each of these systems represents a critical point for the potential risk of contagion. Therefore, the presence of Legionella constitutes a serious risk for hospitals, healthcare and social care facilities, industries, businesses, hotels, condominiums, schools, etc.
In these and other structures, in the absence of an adequate risk assessment and a suitable water treatment system, it can be difficult, if not impossible, to keep the potential danger posed by the presence of Legionella under control.
Water Safety 360° and SANIKILL are the optimal solutions for best defending against this danger.
What is the difference between Legionella and Legionella pneumophila?
Legionella pneumophila is a species belonging to the genus Legionella, which currently includes more than 70 species, some of which, like pneumophila, are pathogenic to humans.
Legionella pneumophila is the species most frequently associated with human infections (it is also the only one for which a rapid diagnostic system is available, namely the urinary antigen test), but cases of infections caused by other species (such as Legionella feeleii, Legionella micdadei, Legionella anisa, and Legionella longbeachae) are also documented.
Are there guidelines or legislative decrees regulating the control of Legionella?
The topic is also addressed in the most recent report by the Istituto Superiore di Sanità (ISTISAN Report 22/32)
“Guidelines for the evaluation and management of risk for water safety in the internal distribution systems of priority and non-priority buildings and in certain ships pursuant to Directive (EU) 2020/2184,” which defines priority classes to categorise various buildings, and outlines different requirements for each identified class for the correct risk assessment and management. The classification includes hospital, healthcare, socio-care, and tourist-hotel structures, spas and wellness centres, gyms, prisons, ships, stations, airports, and catering sector establishments.
At the legislative level, as early as 2008, Legislative Decree No. 81/08 and the State-Regions Agreement of 2013 and 2015 (79/CSR of 07/05/2015) had imposed an appropriate risk assessment and management of Legionella in workplaces, given that this bacterium belongs to risk class 2.
However, the real novelty regarding Legionella was introduced in 2023 by Legislative Decree 18/2023, which transposed Directive (EU) 2020/2184 concerning water intended for human consumption and included Legionella among the potability parameters, particularly for internal building networks. This requires the consideration of this parameter in the development of the water safety plan prescribed by the same decree.
How is the proliferation of Legionella controlled?
There are various preventive measures that can prevent the uncontrolled proliferation of Legionella. Among the most basic and simple to implement are periodic descaling and disinfection of the terminal components of the water distribution circuit, appropriate flushing, removal of dead branches, and maintaining and controlling adequate temperatures. However, more advanced and effective measures would be preferable, especially in high-risk structures, such as periodic cleaning and sanitisation of tanks, reservoirs, and accumulations, as well as the use of continuous water disinfection systems with a product suitable for potable water treatment, such as SANIKILL.
What are the risks associated with the presence of Legionella in drinking water or hot sanitary water?
When the potable or hot sanitary water distribution system is contaminated by Legionella, small droplets of water containing the bacterium (such as those generated by a shower) can be easily inhaled by the user during simple daily activities and reach the lungs. Depending on the individual’s predisposition and risk factors, this can cause an infection and lead to diseases ranging from Pontiac Fever to the more severe and deadly Legionnaires’ Disease.
To prevent these risks, Sanipur has developed the patented SANIKILL technology, the most effective in eradicating Legionella in water circuits.
