Legionella Risks in the UK: Statistics and Guidance for Businesses

Legionnaires’ disease—a serious form of pneumonia caused by Legionella bacteria—continues to present a notable public health concern across the UK. A comprehensive report released last year sheds light on the prevalence and risks associated with Legionella, underlining the importance of awareness and prevention.

This guide explores the latest data and outlines practical steps businesses can take to minimise risk and protect both employees and customers.

Legionella in the UK: Key Statistics

In 2023, there were 604 confirmed cases of Legionellosis in England and Wales, all identified as Legionnaires’ disease. This marks an upward trend compared to previous years and signals growing concern. Key findings include:

• Gender and Age Distribution: 70.2% of cases were male, and 64.2% were aged 60 or older.

• Smoking as a Risk Factor: Smoking was reported in 80.5% of cases, demonstrating a strong correlation with susceptibility.

• Incidence Rates: England saw an incidence rate of 1.0 per 100,000 people, while Wales reported a slightly higher rate of 1.4 per 100,000—though this difference falls within statistical error margins.

• Sources of Exposure:

  • Community-acquired cases: 62.7%

  • Travel-related cases: 35.1%

  • Healthcare-associated infections: 2.2%

    
    

These figures show that most infections occur in the general community, with healthcare environments contributing a relatively small proportion.

Regional Variations in Cases

Geographical data revealed significant regional differences:

• Highest Case Numbers: The South East recorded the most cases (100).

• Highest Incidence Rates: The East and West Midlands had the highest per capita rates (1.2 per 100,000).

• Lowest Incidence: The North East had just 17 cases, equating to 0.6 per 100,000.

  
  

Environmental factors and population density may partly explain these variations, though further investigation is needed to determine statistical significance.

Business Responsibilities: Preventing Legionella

Although Legionnaires’ disease is relatively rare, its severity and high mortality rate make prevention a critical responsibility—especially for businesses operating water systems or facilities that produce aerosolised water droplets.

1. Regular Testing and Monitoring

Routine water testing is essential for early detection. Businesses should use specialised test kits or accredited laboratories to monitor water systems and address contamination promptly.

2. Conducting Risk Assessments

Comprehensive risk assessments are a legal requirement under UK health and safety regulations. These assessments should:

• Identify all water systems.

• Evaluate potential for Legionella growth.

• Implement and document appropriate control measures, following HSE guidance.

3. Water System Maintenance

Proper maintenance is vital to reduce the risk of Legionella proliferation. This includes:

• Regular flushing of unused water outlets.

• Cleaning and descaling tanks, pipes, and cooling systems.

• Maintaining safe water temperatures (hot water above 60°C, cold below 20°C).

  
  

These practices limit the growth conditions for Legionella, such as stagnant water or biofilm build-up.

4. Staff Training and Awareness

Ensuring employees are educated about Legionella risks and control methods is key. Proper training helps staff identify potential hazards and implement safe practices. Partnering with Legionella specialists can further strengthen your prevention strategy.

A Proactive Approach Saves Lives

With Legionnaires’ disease cases rising, businesses must take proactive steps to prevent outbreaks. While most cases occur outside of healthcare settings, every organisation that operates water systems has a duty to minimise risk.

Prevention is better than cure—and in the case of Legionella, it could be lifesaving.

If you need professional support or testing services, contact us today to ensure your systems remain safe and compliant.