Legionnaires : The hidden killer

Covid-Secure Returning to Work – Legionella

As businesses return and prepare for the ‘new normal’ risk assessment is the phrase on everyone’s lips. Social distancing, PPE, hygiene, and cleanliness is all at the front of our minds but one of the dangers lingering in many workplaces – legionella bacteria.

What are Legionella Bacteria?

It is bacteria that mostly grows in warm dirty water, and is at its most prolific at around 37°C. Legionellosis is the collective name given to the pneumonia-like illness caused by legionella bacteria. This includes the most serious legionnaires’ disease, as well as the similar but less serious conditions of Pontiac fever and Lochgoilhead fever.

Where are Legionella Bacteria found?

In nature the bacteria live in fresh water but are very rarely known to cause illness.
However, man-made water systems that are poorly maintained can create environmental conditions could be the ideal host for legionella bacteria. These include Faucets and Showers, Air Conditioning systems, Humidifiers, Pipework, and leisure facilities such as hot tubs and pools.

How is Legionnaires Disease dangerous to us?

Legionnaires Disease is a severe form of Pneumonia, caused by bacteria called Legionella. It is caused by breathing in small droplets of water, that contain the bacteria, into the lungs. Typically, this would come from a shower or air conditioning unit or other source of water vapour. There is no scientific evidence to say it can be contracted by drinking.

There is an increased risk for:

  •  Over 50’s and those with poor lifestyle including heavy drinking and smoking
  •  People with pre-existing respiratory problems
  •  People with weakened immune systems due to illnesses such as diabetes, cancer, or kidney failure

However, healthy individuals may also be at risk. Signs and symptoms include:

  • Cough
  • Shortness of Breath
  • Headache
  • Fever
  • Muscle Aches
  • Diarrhoea

The disease can be treated with antibiotics and whilst most people who develop symptoms may need care in hospital, most make a full recovery. If you show any symptoms be sure to get advice and health care from your GP or hospital and make sure to advise them of any recent nights away from home, use of hot tubs and different showers and even working in unfamiliar or recently reopened facilities.

Public Health England published the Monthly Legionella Report December 2019 (National surveillance scheme for Legionnaires’ disease in residents of England and Wales). The report (correct as of 10 January 2020) reports 503 as the ‘Number of confirmed cases of Legionnaires disease since 01 January 2019’

How can we control/manage it?

As an employer or someone in control of a premises – including landlords of residential accommodation – you have a duty under general health and safety law to protect your employees, contractors, visitors etc. that could be exposed to any contaminated water droplets. There may be a risk of exposure if you have air conditioning units, cooling towers, hot and cold-water systems.
Temperature control is the first and most effective method with biocides, chemicals and physical measures used in certain situations. Maintenance procedures are key and should form part of a suitable and sufficient risk assessment. As with other areas of your business you may need to seek external specialist advice and implement suitable controls.

In Summary: Assess – Record – Communicate

  • Carry out a legionella risk assessment
  • Appoint a responsible person for day-to-day awareness and monitoring – Ensure suitable training for individual(s)
  • Seek specialist advice and guidance where necessary
  • Keep appropriate surveys and records of water systems with associated maintenance documentation and safe operating procedures
  • Communicate relevant information to all persons who may be affected, using signage where required

Further guidance can be found in the following guidance documents to advise you on how to manage your duties (click on the links to read):

🔗 HSG274 Part 1 Legionnaires’ disease: The control of Legionella bacteria in evaporative cooling systems
🔗 HSG274 Part 2 Legionnaires’ disease: The control of Legionella bacteria in hot and cold-water systems
🔗 HSG274 Part 3 Legionnaires’ disease: The control of Legionella bacteria in other risk systems
🔗 INDG458 Legionnaires’ disease: A brief guide for duty holders