What is Legionnaires' Disease?

Legionnaires' disease is a potentially fatal form of pneumonia caused by Legionella bacteria. Whilst this bacteria is widespread in natural water systems such as rivers and ponds, it is rare to catch the disease from these sources due to the conditions typically required for growth and transmission.

Specifically, Legionnaires' disease is contracted by inhaling airborne droplets of water that contain the bacteria. This exposure occurs most frequently at outlets where water is dispersed into the air as steam, such as showers, taps, hot tubs, and spa features. These outlets are fed by larger water systems, including cooling towers and hot and cold water systems. Should water temperatures in these systems fall within the 20–45 °C range, Legionella bacteria has the highest chance of rapid, successful growth. However, bacterial survival remains possible outside this range, which is why regular risk assessments and testing of these water systems is so important.

The likelihood and severity of infection following exposure varies depending on individual vulnerability. Although possible for healthy people to become infected with Legionnaires' disease, the most at-risk populations include:

• Immunocompromised people
• People over the age of 45
• Smokers and heavy drinkers

Given the potential severity of infection, recognising the early signs of Legionnaires’ disease and seeking prompt treatment is critical

Symptoms and Treatment

Legionnaires' disease must be treated with antibiotics as soon as possible. When not treated promptly, it can lead to a number of life-threatening complications such as respiratory failure. 

Initial warning signs of Legionnaires' disease often presents as flu-like symptoms, including:

• Coughing
• Shortness of breath
• Chest pain or discomfort
• Fever
• Muscle pain

As the infection progresses, symptoms can become more severe and may include confusion, persistent high fever, and worsening breathing difficulties.

Due to the similarity with other respiratory illnesses, Legionnaires’ disease can be difficult to identify without clinical testing. Anyone experiencing these symptoms, particularly following potential exposure to aerosolised water, should seek medical attention as soon as possible.

Given the potential severity and difficulty in early identification, preventing exposure through effective water system management is essential.

Prevention and Testing

Prevention of Legionnaires' disease relies upon effective water system management, ensuring systems are designed and monitored to limit conditions that support bacterial growth. Deposits such as rust, sludge, scale, organic matter and biofilms support growth by providing a source of nutrients for the organism, and without regular cleaning and control these materials can accumulate and further increase risk.

Routine monitoring and testing also forms a fundamental part of any comprehensive water management plan. As per HSE guidance, open water systems such as cooling towers, evaporative condensers and spa pools should have routine testing carried out by a UKAS accredited laboratory at least quarterly to help identify contamination early and prevent the spread of harmful bacteria.

How We Help

At Envirochem, we offer UKAS-accredited Legionella testing services that detect and quantify the presence of bacteria, allowing water management companies to quickly detect changes, determine whether quality has been compromised and effectively implement the right corrective measures.

Additionally, we offer self-sample testing and analysis kits for domestic homeowners with pools and hot tubs for whom large-scale management services may be out of reach. Every kit comes with a comprehensive safety guidebook and all the necessary PPE equipment to ensure that you can collect samples confidently and safely. Backed by the same commitment to accuracy and safety as our full-service solutions, these kits empower you to take proactive steps to ensure your health and safety.

For tailored advice and actionable strategies to manage Legionella risks effectively, get in touch with one of our experts or visit our Legionella testing page.