As we’ve been discussing on Twitter this week, there’s a serious lack of understanding on Legionella, even among property professionals. We try to do our bit to educate our customers by running training courses as well as writing our weekly advice blogs, but here are some of the more surprising facts about this potentially dangerous bacteria which you may not have heard before.

Legionella can be found in soil and compost as well as water

Did you know that Legionella bacteria can live very happily in damp soil or compost? There have been cases of people catching Legionnaires’ disease from gardening, and in particular, compost. When opening up a plastic sack of compost and agitating the organic matter, Legionella-laden moisture particles can be released into the air and then breathed in by the gardener. One of our LinkedIn followers, whose partner sadly died of the disease after it’s thought he inhaled it while working as a landscape gardener, recently suggested that compost should be sold with face masks and others have campaigned for warnings to be printed on bags of compost. Our advice is to make sure you work with compost in a well-ventilated area and keep your face away from the bag opening. It’s also worth checking out these handy hints from the RHS on working safely in the garden to reduce the risk from Legionella.

You can inhale Legionella when drinking contaminated water

We mostly associate breathing in Legionella bacteria while using a shower or standing over a running tap, but if a drinking water supply carries Legionella bacteria it is possible to breathe it in while swallowing the water. If you splutter or cough as you drink it creates aerosol particles which can then enter the lungs and cause an infection. That’s why, if an outbreak of Legionnaires’ disease occurs, it’s likely that people in the affected building will be instructed to drink bottled water until eradication of the bacteria has occurred.

It may be possible for Legionnaires’ disease to be transmitted from person to person

It has always been believed that Legionnaires’ disease cannot be spread via personal contact (even if an infected person sneezes or coughs in the vicinity of others), but earlier this year there was a case identified where person-to-person transmission is thought to have occurred. The situation arose in Portugal where a maintenance worker contracted Legionnaires’ disease from a cooling tower at his place of work. During the incubation period, before his symptoms started, he travelled 300km back to his mother’s home. He then became ill and she took him to hospital. A week later his mother started to show signs of infection and was admitted to hospital and she sadly died within a month. Tests showed that the bacteria was the same strain yet there was no evidence of Legionella present in the water system of the woman’s house or places she frequented. The authorities concluded that she caught the infection from her son while nursing him prior to his admission to hospital.

Cases of Legionnaires’ disease may be significantly under-reported

While there are only around 300 cases of Legionnaires’ disease diagnosed in the UK each year, it is thought that the actual occurrence could be much higher as the symptoms are very similar to pneumonia, which is diagnosed in around 300 people per 100,000 of the population each year. Microbiologist Dr Tom Makin believes that “two to three per cent” of pneumonia sufferers actually have Legionnaires’ disease but are just not tested for it.

Train travel is a risk factor for Legionnaires’ disease

One of the most common factors in a Legionnaires’ disease diagnosis is travel, often to other countries (where water hygiene standards may be lower) or where the patient has recently been on a cruise or stayed in a hotel. However, tests show that trains also fall into the high risk category, with as many as one in three trains thought to have Legionella in their water systems. Public health consultant Dave Harper says, “People are surprised that it’s been found on trains but conditions there are perfect for it. The water tanks are located in the roof of carriages and are difficult to access and disinfect. They are often not refilled for weeks or even longer, and in warm weather they can heat up to temperatures that allow the Legionella bacteria to thrive.”

As these examples show, Legionella and Legionnaires’ disease are complex problems which are not necessarily being dealt with adequately. We firmly believe that it is largely a preventable condition if water systems are clean and well-managed, but much more needs to be done if this is to be achieved. Better education for professionals, medics and consumers alike is just the starting point, and with antibiotic resistance a growing problem for the treatment of such diseases, action is needed sooner rather than later.