Legionella in drinking water – important information for Switzerland
Legionella are bacteria that occur in water sources and can be harmful to health under certain conditions. In Switzerland, they are a significant issue, particularly in connection with drinking water and hot water systems. Therefore, various technical measures must be taken during the treatment and distribution of drinking water to prevent the unacceptable proliferation of microorganisms such as Legionella.
Here you will find all the important information about Legionella, how to minimize risks, and the applicable legal requirements.
Legionella are bacteria that occur naturally in freshwater. These microorganisms are particularly dangerous when inhaled via water vapor, as they can cause severe pneumonia, also known as Legionnaires' disease. Legionella multiply primarily in warm water and thrive in temperatures between 25 and 45 degrees Celsius. Therefore, they are frequently found in certain environments such as hot water pipes, air conditioning systems, and whirlpools. Anywhere where significant amounts of water vapor are generated is a potential source of Legionella. Infection can occur through the inhalation of bacteria-containing aerosols.
Legionella bacteria can multiply very rapidly under ideal conditions, such as in stagnant water at optimal temperatures. The number of bacteria can double within just a few days if no water hygiene measures are taken. Systems where water stagnates for extended periods, such as unused water pipes or poorly maintained water tanks, are particularly at risk. To prevent Legionella growth, regular maintenance and adherence to temperature limits are essential. Factors such as poorly maintained water heaters or outdated pipework can promote bacterial growth.
Legionella bacteria in drinking water pose a serious health risk. Although the bacteria themselves do not usually cause infection, inhaling contaminated water vapor, for example while showering, can trigger an infection. The risk of Legionella contamination is particularly high in larger buildings such as hotels, hospitals, or nursing homes, where complex water systems are present. Regular water quality testing and compliance with legal guidelines are therefore essential to prevent Legionella in drinking water and protect the health of users.
Legionella bacteria are therefore more than just a problem in large water systems – they can lurk anywhere water is heated and inhaled in the form of steam.
Legionella infection often manifests as Legionnaires' disease. The initial symptoms of a Legionella infection resemble those of the common flu, including fever, chills, headache, and muscle aches. If the infection spreads, it can lead to severe pneumonia with symptoms such as shortness of breath, chest pain, and coughing. This disease requires immediate medical treatment, as it can quickly become life-threatening without it. Gastrointestinal symptoms such as diarrhea and nausea are also possible. These symptoms should be taken seriously, as the disease can become severe if left untreated.
Legionnaires' disease, caused by inhaling Legionella bacteria, is a particularly severe form of pneumonia. It typically manifests 2 to 10 days after infection and can lead to serious respiratory problems. The disease is especially problematic in large water systems such as hospitals, nursing homes, and hotels, where Legionella bacteria can multiply under ideal conditions. The source of infection is often hot water pipes, fountains, steam rooms, or showers, where the bacteria can colonize. The Swiss Federal Office of Public Health is also intensifying its efforts to combat Legionella with the "LeCo" project to prevent such infections.
Are Legionella bacteria dangerous?
Yes, Legionella bacteria are extremely dangerous and pose a serious health risk. According to the World Health Organization (WHO), the number of bacterial infections caused by Legionella has increased worldwide in recent years. Older people and those with pre-existing conditions are particularly at risk, but even healthy individuals can become seriously ill. According to the WHO, Legionnaires' disease is fatal in 5 to 10% of cases.
The long-term consequences of a Legionnaires' disease infection can be serious. Even after recovering from Legionnaires' disease, many sufferers experience long-term health problems. These include persistent respiratory problems, chronic fatigue, and general weakness. In some cases, permanent lung damage can even occur. Older people and those with pre-existing conditions are particularly susceptible to such long-term effects. These health limitations can significantly reduce the quality of life for those affected and often require extensive follow-up care and rehabilitation.
In summary, Legionella bacteria are not just a temporary problem, but can have long-term health consequences. To protect against these risks, it is important to regularly check potential sources of infection, such as drinking water pipes and showers, and to ensure compliance with legal regulations.
Limescale deposits in water pipes can pose a significant risk for the development and proliferation of Legionella bacteria. Irregularities in the pipes caused by limescale deposits promote the formation of biofilms. Limescale deposits in boilers impede the free flow of water and create so-called "dead zones" where the water stagnates. Biofilms form in these zones, providing ideal conditions for Legionella bacteria to feed and multiply. Additionally, limescale impairs heat transfer in the boiler, often resulting in the necessary temperatures to kill Legionella bacteria not being reached.
Rust, which forms through corrosion, further exacerbates the problem. Rust particles provide bacteria with protection and additional nutrients, promoting the growth of Legionella. This combination of stagnant water, limescale, and rust creates an ideal environment for Legionella, especially in older or poorly maintained boilers.
Boilers are a known risk area for the proliferation of Legionella bacteria, as they often keep water at temperatures between 25 and 45 degrees Celsius – a temperature range ideal for the growth of these dangerous bacteria. If the boiler is not regularly heated to 60 degrees Celsius and above to kill Legionella, the bacteria can multiply unchecked. This is particularly dangerous if the boiler is not used for extended periods or if limescale and rust build up in the system.
To prevent Legionella in the boiler, regular maintenance is crucial. This includes regularly descaling the boiler and heating the water to at least 60 degrees Celsius. When the boiler is not in use for extended periods, it should be completely drained to prevent biofilm formation and Legionella growth. Therefore, regular maintenance and flushing of water pipes are essential to minimize the risk of Legionella infection. In areas with hard water, it is recommended to install a limescale protection system to reduce limescale deposits and thus minimize the risk of Legionella.
An effective method for combating Legionella is to deprive it of its breeding ground and multiplication environment. The Mediagon limescale protection system, for example, combats Legionella indirectly by reducing limescale and rust in the pipe system. By preventing limescale deposits, the formation of biofilms is hindered, which effectively inhibits Legionella growth. This preventative measure can significantly reduce the risk of Legionella contamination.
In summary, limescale deposits are a crucial factor in the growth of Legionella bacteria. Boilers and water pipes in hard water areas are particularly susceptible. To prevent Legionella, it is important to carry out regular maintenance and avoid limescale buildup.
Mediagon limescale protection combats Legionella indirectly by depriving them of their breeding ground and breeding ground – namely limescale and rust – in the pipe system.
Combating Legionella requires a targeted approach that encompasses several aspects. Here are the essential methods for effective Legionella control:
Kill Legionella
To effectively kill Legionella bacteria, it is important to regulate the water temperature accordingly. Legionella bacteria die when the water is regularly heated to over 60 degrees Celsius. Modern heating systems are often set to regularly raise the water temperature above 60 degrees Celsius, but only for short periods. This ensures that all Legionella bacteria in the system are killed. For hot water boilers, a minimum temperature of 55 degrees Celsius is generally recommended to prevent the growth of Legionella and thus guarantee safe water quality.
At what point do Legionella bacteria die?
Legionella bacteria begin to die at temperatures above 60 degrees Celsius. This temperature control is crucial to ensure effective Legionella control. It is therefore important to regularly check the water temperature and ensure it is high enough to kill the bacteria. Temperatures below this range provide favorable conditions for Legionella growth and increase the risk of contamination.
Legionella test
Regular Legionella testing is crucial to ensure that water is free of Legionella bacteria. These tests are conducted by specialized laboratories that analyze water samples for the presence and concentration of Legionella. In large buildings such as hotels, hospitals, or office buildings, regular testing is particularly important to guarantee safe water quality and minimize the risk of Legionella infections.
Legionella and water temperature
Controlling water temperature is a key aspect of Legionella prevention. Temperatures below 25 degrees Celsius promote the growth of Legionella bacteria, while temperatures above 60 degrees Celsius kill them. Therefore, it is crucial that the water system is regularly adjusted to the correct temperature and that there are no stagnant areas of water that could encourage Legionella growth. Regular temperature monitoring helps ensure water safety.
Shower head with legionella filter
A Legionella filter in the showerhead can provide an additional layer of protection against Legionella. These filters are specifically designed to remove Legionella and other microorganisms from the water before it reaches the showerhead. Using such filters complements regular maintenance and helps to further reduce the risk of Legionella infections. --> Can our sales representatives offer anything?
In Switzerland, the number of Legionnaires' disease cases has increased in recent years, prompting the Federal Office of Public Health (FOPH) to intensify its coordination of measures. The FOPH has established a special Legionella task force to coordinate the control and prevention of Legionella in drinking water. This initiative underscores the importance of strict drinking water regulations to protect public health.
The Swiss Federal Office of Public Health recommends regular maintenance measures to prevent Legionella in drinking water. This includes regularly descaling water heating systems to prevent limescale buildup. The 115-page recommendation report from the FOPH emphasizes that high water temperatures promote the formation of limescale. These deposits lead to irregularities in the pipes and the accumulation of stagnant water, which encourages the formation of biofilms. Legionella bacteria can colonize and multiply in these biofilms, both as free-living organisms and within amoebae and other protozoa.
Limescale deposits can form on faucet components, such as aerators, providing bacteria with additional protection and promoting their growth. Therefore, these components must be cleaned and descaled regularly to minimize the risk of Legionella contamination.
Mediagon water treatment offers an effective solution for combating Legionella by reducing limescale and rust deposits in the pipe system. Removing these breeding grounds reduces the risk of Legionella proliferation. This preventative measure complements the recommendations of the Federal Office of Public Health (FOPH) and contributes to ensuring high water quality.
Overall, it is crucial that all measures for combating Legionella are adhered to in order to guarantee the safety of drinking water and minimize health risks.
