Legionella thrives best in warm fresh water at temperatures between 25 and 45 degrees. Because the disease-causing bacteria are transmitted through plumbing, most infections happen at home. This is especially the case if the water temperature is set too low for a longer period of time. The pathogens can be inhaled through the resulting water vapor in the shower and cause a serious infection in the person’s lungs.
Set the right temperature
Because building plumbing is the ideal breeding ground for Legionella and pathogens of all kinds, setting the right water temperature is critical to killing pathogens and thus preventing outbreaks.
Over time, a so-called biofilm forms in the pipes, which provides the optimal breeding ground for bacteria. Especially if the pipes and fittings contain rubber or plastic, the formation of the biofilm and thus the multiplication of pathogens can be promoted.
To kill legionella in drinking water, a temperature of more than 60 degrees is required. However, as many consumers as well as public institutions reduce general water consumption and water temperature in times of energy crisis and inflation, the development of legionella is additionally favored. However, if you want to contain the risk of legionella in the long term, you should never set the hot water temperature below 60 degrees. Also in the pipes temperatures should not reach less than 55 degrees.
Symptoms of infection
In most cases, Legionella infections occur through droplet transmission. The warm water coming out of the shower head during showering causes a water vapor, which allows the bacteria to spread through the air and be inhaled into the lungs. People with weakened immune systems, those suffering from chronic diseases, babies, the elderly and smokers are considered to be particularly at risk.
Infection with Legionella can cause various diseases with different symptoms:
Legionnaires’ disease: Legionnaires’ disease is a severe form of pneumonia. As a rule, there is a relatively short incubation period here, so that the first symptoms appear after a short time.
These include, in particular, chest pain, headache, chills, cough and high fever of more than 40 degrees. In some severe cases, the high fever can even lead to delirium or confusion. In addition, Legionnaires’ disease may also be associated with abdominal pain, diarrhea, and vomiting.
The course of this pneumonia is predominantly very severe and can last up to four weeks. In every tenth case, it is even said to be fatal.
Pontiac fever: Pontiac fever is a somewhat milder form of Legionella infection. The disease is manifested by flu-like symptoms. Those affected often complain of symptoms such as general malaise, headaches, aching limbs and fever. Cough as well as chest pain are also not uncommon. However, within two to five days the body should recover from the disease. There are no records of any deaths or late effects.
Urinary tract infection: Under certain circumstances, Legionella infections can also cause a urinary tract infection.
Do not panic when washing your hands
The drinking water from the tap in our home should ideally be germ-free as well as free of pollutants and have the optimum water hardness. However, even if the water contains a small amount of legionella, this is not necessarily a reason to panic. Benedikt Schaefer, a biologist with the Federal Environment Agency, gives the all-clear: “Legionella occurs everywhere there is water.”
For example, they can be found in water pipes, shower heads, swimming pools, air-conditioning systems or other damp installations with optimal breeding grounds. While it is true that Legionella proliferate particularly well under certain conditions – for example, when the humid environment is additionally warm – this should not mean that human health is directly at risk.
Both drinking and washing hands should not be a problem despite Legionella contamination in drinking water, according to the biologist at the Federal Environment Agency. A greater danger is said to be atomized or evaporating water in the air when showering, as the bacteria can thus find their direct way into the lungs and cause corresponding pneumonia.
Risk of infection lurks especially abroad
The benefits of drinking water are undeniable. However, consuming tap water is not safe in every country in the world. The risk of infection is said to be particularly high abroad. Back in the seventies, one of the largest outbreaks of Legionnaires’ disease occurred at a reunion of American veterans.
When staying abroad in hotels or vacation homes, you should therefore always make sure to drink bottled water only. However, if symptoms such as general malaise, fever, cough, headache, aching limbs or watery diarrhea occur during or immediately after a trip abroad, it is advisable to consult a doctor at short notice and inform him or her of the possibility of Legionella infection.
Can I take a shower with legionella?
Since atomized or evaporating water carries the pathogens directly into the lungs of humans, a shower ban may well be issued in the event of a Legionella infestation. The risk of infection is too high in such cases, so health takes priority. Infection can be prevented by a legionella filter.
How long shower ban for legionella?
Basically, the length of the shower ban for Legionella depends on different factors, such as the load. In the past, such a shower ban has often lasted for several months.
Is it possible to brush teeth with legionella?
Yes, as a rule, brushing teeth is possible despite legionella. Washing the body should not be a problem either, as long as there is no spray that swirls germs into the air.
What do I do if I have legionella in the water?
If Legionella is detected in the drinking water, killing the bacteria is required. For the so-called thermal disinfection of the drinking water system you should contact experts. Legionella filters are required for immediate protection.
Basically, legionella in the water pose a danger when showering. Legionella infection can be promoted by the water vapor, which could make the shower head off-limits if an infestation occurs. Simple hand washing or even drinking water should nevertheless not be a problem.
To prevent legionella, weekly heating of the hot water tank to at least 60 degrees is useful. In many buildings, a so-called legionella circuit is already installed, which automatically heats the hot water once a week, so that the residents of the house do not have to worry about legionella. If you still want to be safe, a legionella filter can protect you from infection.