What Is Legionella & Why Is It Dangerous?

Caledonian Heating • 21 June 2023

Legionnaires’ disease is a form of pneumonia that can be very harmful to a person, with symptoms including a cough, shortness of breath, fever, muscle pains, headaches, vomiting and diarrhoea. It is caused by exposure to any species of Legionella bacteria. Legionella is found in freshwater and exposure to it can lead to Legionnaires’ disease.


Read on to find out more about Legionella and why it is so dangerous.



What Is Legionella?

Legionella is a bacteria that is common in many environments, with at least 50 species and 70 serogroups identified. The bacteria can cause Legionnaires' disease and also a flu-like illness called Pontiac fever. The bacteria is not transmissible from person to person and is most commonly found in poorly maintained water sources when an outbreak occurs.


Legionella acquired its name in 1976 when an outbreak of an unknown disease affected 221 people and caused 34 deaths. The outbreak was noticed among attendees at a convention for an association of military veterans called the American Legion - hence Legionella. The bacterium was found to be breeding in the cooling tower of the hotel’s air conditioning system and spread through the building where the convention was being held.


Treatments & Prevention

No vaccine is available for Legionnaires disease, which is why it is very important to test for evidence of Legionella. While people recover, some symptoms can lead to hospitalisation or even death. About one-third of people cough up blood and up to half suffer from gastrointestinal and neurological symptoms. The mortality of the original outbreak in 1976 was pretty high, but now with antibiotic treatments the mortality rate has gone down to less than 5% if treatment begins quickly.


The best way to prevent Legionella is to regularly test for it and enforce a strict water safety plan. This commonly involves keeping the water temperature above or below the range in which Legionella typically thrives, periodically disinfecting the system and preventing stagnation.


Legionella Testing From Caledonian Heating Ltd

Caledonian Heating & Plumbing Ltd offers Legionella control and risk assessments for clients in the Edinburgh and Dundee areas. We are members of the Legionella Control Association and can work with you to ensure your water systems are clear from Legionella and in compliance with the current Legionella legislation.


Our experts will work to carry out risk assessments and then testing. After this, if evidence of Legionella is discovered we will carry out a tailored Legionella control plan to ensure your systems will be free from Legionella in no time at all. Our risk assessments can be carried out on mains water systems, hot water systems, water storage containers, showers, fountains, pools, AC systems and more.


If you’re concerned about the potential of Legionella being present in your systems, get in touch with us today to find out more and book risk assessment and testing.

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