Myth-busting: the truth about Legionella and Legionnaires’ disease

Myths about Legionnaires' disease and Legionella

There is a multitude of misinformation about Legionella, and Legionnaires’ disease myths, in circulation, so this month we’re on a mission to set the record straight with a few facts. Thanks to working in water hygiene management for over 20 years, we’ve just about heard all the Legionella legends out there, so allow us to clear up any confusion.

Myth 1: building owners need to have a Legionella certificate

There’s no such thing as a Legionella certificate! Employers and landlords must prove that they have carried out a Legionella risk assessment for their property but there is no requirement for a certificate of any sort. Anyone trying to sell you one is a cowboy so steer clear.

Myth 2: water must be tested for Legionella

Water only needs to be tested for Legionella in certain circumstances, primarily where there is a higher risk or a suspicion that Legionella may be present in a water system. As a matter of course, domestic rental property does not require the water to be tested, unless there is cause for concern. Similarly, office buildings and other places of work where the risk from Legionella is low and there are adequate controls in place would not require regular testing. Higher risk properties like hospitals and care homes or large facilities such as hotels or leisure centre with air conditioning systems or other water-based features (e.g. spas, swimming pools, fountains) should carry out routine testing as part of regular Legionella monitoring procedures. If in doubt, contact us for advice.

Myth 3: only old people are susceptible to Legionnaires’ disease

While age is one of the risk factors for Legionnaires’ disease, with those over 45 deemed to be at greater risk, it is possible for anyone to be infected. From new born babies picking up the bacteria in a birthing pool to smokers, heavy drinkers or those suffering with health conditions such as heart disease, diabetes, asthma or immune deficiency, everyone could become ill under the right conditions.

Myth 4: you can’t be infected by drinking water

Legionella bacteria infiltrates the lungs when it is breathed in via airborne water droplets. In the majority of cases this is in the form of steam, spray or mist emitting from a shower, tap, air conditioning system, hot tub or similar environment. However, it can also happen if a person chokes on a glass of Legionella-carrying water while drinking, thus allowing the bacteria to enter the lungs. This is why people who live or work in buildings where a Legionella problem has been identified are usually advised to drink bottled water until the plumbing system has been treated.

Myth 5: Legionnaires’ disease is difficult to diagnose

There is a simple urine test for Legionnaires’ disease which can give a quick and accurate diagnosis, but it is often the case that patients’ symptoms are confused with those of other illnesses such as pneumonia or flu. Since Legionnaires’ disease is relatively rare, and the symptoms can be varied and myriad (e.g. high temperature, feverishness and chills, cough, muscle pains, headache, diarrhoea, signs of mental confusion), doctors often test for a multitude of other infections or conditions before testing for it.

Myth 6: all Legionella bacteria is dangerous to humans

There are at least 50 different strains of Legionella bacteria but fewer than half of them (currently thought to be 20 in total) can cause illness in humans. Legionella pneumophilia is the variant which causes Legionnaires’ disease.

No doubt we haven’t covered all the Legionnaires’ disease myths out there, so feel free to comment below to add in your own favourites, or ask us questions if you’re having trouble sorting fact from fiction.

Article originally published