Legionella

Legionella

Legionella

What is Legionella?

The term Legionella refers to a group of bacteria that are common in natural water supplies such as ponds. Legionella bacteria normally only become a health problem once they have the opportunity to multiply in an industrial or domestic water system and an individual inhales water droplets that contain the bacteria. However, not everyone that is exposed to the bacteria will become unwell, though there are individuals that are more susceptible:

  • Elderly and Infirm
  • Individuals with Diabetes
  • Individuals with Chronic Heart Disease
  • Individuals with Smoking Related Illnesses
  • Individuals with other underlying health conditions

Since Legionella has been discovered, there have been over 58 species of Legionella identified.

Legionnaires Disease, Pontiac Fever & Lochgoilhead Fever

Legionellosis covers any illness caused by Legionella bacteria examples of these are: Legionnaires Disease, Pontiac Fever and Lochgoilhead fever.

Pontiac and Lochgoilhead fever are less severe forms of illness as a result of inhaling Legionella bacteria. Primary symptoms of these fevers include:

  • Fever
  • Muscle Pains

Symptoms of Pontiac and Lochgoilhead fever normally take anywhere between a few hours to 3 days to develop and usually lasts for a week. A urine test can diagnose sporadic cases, however, there is no known treatment of these fevers. For most people, this is a self-limiting influenza like illness and symptoms should be treated appropriately based on clinical assessment of severity. 

Legionnaires Disease is the potentially fatal form of pneumonia that an individual can get as a result of inhaling Legionella bacteria. The symptoms of Legionnaires Disease can include:

  • Cough
  • Shortness of Breath
  • Fever
  • Muscle Aches
  • Headaches
  • Diarrhea

Symptoms usually begin about 7 days after exposure but can be anywhere between 2 and 19 days. For most individuals, this is a self-limiting illness but for the individuals mentioned, if they develop pneumonia symptoms they should see a doctor immediately and mention that they may have been exposed to Legionella.

Despite there being 503 confirmed cases in 2019 (Public Health England), it is estimated that 4,000-10,000 cases of Legionnaires Disease occur every year in the UK.

Prevention of Legionella in Your Water Systems

To deprive Legionella bacteria of the chance of multiplying in your water systems, you need to do the following:

  • Keep Hot Water Hot
  • Keep Cold Water Cold
  • Keep Systems Clean
  • Keep Water Moving

Preventing water contamination means you need to check your water tanks and cylinders regularly for sludge, scale and rust etc. as these all provide nutrients for bacteria to grow. To help prevent these types of contamination, all water systems should be enclosed to prevent matter getting into the system, and extra care is needed if part of a system has not been used for a long time and it is being brought back into use.

To prevent bacteria multiplying you need to ensure that you control the temperatures as the bacteria multiply most quickly between 20 and 45 degrees Celsius. To keep the temperatures controlled, cold water should be kept below 20 degrees Celsius and hot water stored above 60 degrees Celsius, distributed above 50 degrees. The ideal temperature for Legionella to grow and multiply is 37 degrees, which is the same as body temperature. Other methods that are used to control and prevent the growth of bacteria are listed below:

  • Biocides/ Disinfectants
  • Ultraviolet (UV) Radiation
  • Specialised Filtration

To further prevent bacteria multiplying, extra care needs to be taken in regards to dead legs. As a dead leg is a pipe in which water is unused or rarely used, the water within is unable to circulate and therefore, can often become stagnant, giving Legionella and other bacteria the prime conditions that they need to grow. Putting dead legs on a regular flushing regime will prevent and reduce the environments for Legionella and other bacteria to grow.

As Pontiac, Lochgoilhead and Legionnaires Disease are contracted through inhaling water droplets containing the Legionella bacteria, preventing aerosols is one of the main ways of preventing illness. The type of water system that poses the highest risk of dispersing Legionella bacteria are evaporative cooling towers. The key aims of control for this water system are to prevent or reduce corrosion, scale, fouling and growth of bacteria including Legionella and other microorganisms.

Other Water Systems That Can Harbor Legionella

Whilst there are some obvious and common places for Legionella growth, such as spas and whirlpool baths, shower heads and water softeners, there are some less well-known places for Legionella bacteria to grow, these include:

  • Misting or Spray Humidifiers
  • Automatic Washers for Vehicles
  • Fountains and Decorative Water Features (including those on display for sale)
  • Eye Baths and Facewash Fountains
  • Sprinkler and Hose Reel Systems
  • Windscreen Wiper System for Vehicles
  • Industrial Effluent Treatment Plants
  • Fire Suppression
  • Horticultural Misting Systems and Irrigation Systems

However, it is not just these water systems that can cause a Legionella outbreak. The existence of biofilms are also linked to Legionella outbreaks, therefore, it is important to know how to manage these to stop a Legionella outbreak. Biofilms are formed when layers of microorganisms, typically bacteria, combine and group together. By doing this, the bacteria creates a tough protective layer that encloses colonies of bacteria. In layman’s terms, a combination of moisture, surface and bacteria can cause a biofilm to occur.

To prevent biofilms from forming in your water system, Hydraclean Ltd recommend putting processes in place that cover the major risks and minimise the conditions in which the bacteria will flourish if it is left unmonitored. These are:

  • Maintain the Correct Water Temperatures
  • Ensure Adequate and Appropriate Cleaning Routines
  • Allow a Good Flow of Water to Keep Systems Flushed Out

Schemes for Control

Hydraclean Ltd is a business that has worked hard to keep water safe in buildings that individuals live and work in for over 30 years. Public health is our number one top priority alongside ensuring that businesses are Legionella compliant at all times. We offer the following schemes of control to all of our clients:

  • Weekly Flushing
  • Monthly Temperature Checks
  • Quarterly descaling and disinfection of showerheads and hoses
  • Six Monthly Assessment of Tanks
  • By-Annual Review of Risk Assessment Documents
  • Engineering Problems Out with Simpler More Efficient Systems

We have also developed an app to ensure that clients can always access the data for these schemes of control, at any time, to ensure they are compliant and can carry out some of the routine tasks simply ‘In House’. Delta Compliance Online enables multiple sites to be monitored at the same time, saving on admin time and the handling of log books. To find out more about Delta Compliance Online, please visit our website www.hydraclean.co.uk or phone 0161 430 5100.

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