What is Legionnaires disease, how is it spread and who is at risk?
Legionnaires’ disease is a type of pneumonia caused by bacteria that is found in damp or wet environments. The bacteria are not spread from person to person, but instead through airborne water droplets. It is most commonly contracted by breathing in mist or vapour from water that contains the bacteria. Mist or vapor contaminated with the bacteria can come from whirlpool spas, cooling towers or large air-conditioning units and water used for drinking and bathing. The illness can occur at any time of year but is most common during the summer and early fall.
People and workers who are most likely at risk are:
- workers in air-conditioned buildings, including office staff, cleaning staff and security staff
- staff or patrons in air-conditioned venues such as hotels, restaurants, museums, aquariums, gaming venues
- building maintenance workers
- air-conditioning company workers
Most people exposed to the bacteria do not become sick, however, if contracted it can be life threatening but most often can be successfully treated with antibiotics. Legionella cases are classified as outbreaks when two or more people become ill in the same place within approximately the same time-frame, such as patients in hospitals, guests in hotels, worked in the same office building or hospitality settings.
You are more likely to get sick if you in any of the following risk categories:
- over 50 years of age
- smoke or have been a heavy smoker
- have a chronic lung disease
- have a weak or compromised immune system
Legionella bacteria trigger pneumonia, which is inflammation of the lungs. Symptoms include a high fever, chills, cough, muscle aches and headaches, and typically appear two to 14 days after exposure. There are many other causes of pneumonia, however, so diagnosing Legionnaires’ can be difficult. Chest X-rays, along with analyses of phlegm, blood or urine, will be required to show evidence of the bacteria.
In some cases, the Legionella bacteria cause a mild infection rather than a serious one. This condition is referred to as Pontiac fever, which usually lasts two to five days, and there is no pneumonia. The condition may cause fever, headaches, and muscle aches, but the symptoms usually go away on their own.
In general, less than five per cent of people exposed to the bacteria develop Legionnaires’ disease. Of every 20 people who become ill from the condition, one will die of it.
What causes an outbreak of Legionnaires disease?
Although it is estimated that ten per cent or more of cooling towers may be contaminated in a city, most are never found to cause outbreaks of disease. The reason why some cooling towers are associated with outbreaks is unclear, but probably relates to a range of conditions occurring coincidentally. These are likely to include: contamination of the cooling tower, weather conditions such as the level of humidity, sunlight, temperature and wind direction, and susceptible people being located in a position where they can breathe in contaminated water vapour.
Hospitality – a high risk industry
Showers, spa pools and hot tubs are high-risk locations for legionella growth, and all are widely found in hotels and other hospitality industry settings. Furthermore, buildings like hotels tend to have exceptionally complex water systems, and some outlets may be intermittently used due to seasonal variations in demand. This increases the likelihood of dead legs where water is left to stand and stagnate. Complex and large air cooling requirements also present risk areas. The food services industry is also included as hospitality high risk due to the use of complex water systems and large air conditioning towers and systems.
All of the above resources require regular sterilisation, cleaning and testing to remain free of the legionnaires bacteria.
How to reduce the risk of Legionnaires bacteria
Recognise the most common places to find the bacterium. Two of the most common locations where Legionnaires’ disease-causing bacterium can be found are in cooling towers and large central air conditioning systems. The reason for this is that the bacterium likes to multiply in standing warm water, causing the disease to infect people when they breathe in contaminated vapor. Buildings like hotels, RSL Clubs, large restaurants, shopping centres and hospitals, where people gather in large numbers and make heavy demands on heating and cooling systems, are breeding grounds for this disease.
Put preventative maintenance measures in place. Building managers and others who have control over HVAC systems are major lines of defence against the spread of this disease. Although antibiotics can control this condition, as many as 30 per cent of people who contract Legionnaires’ disease can die from it. Stopping the disease from ever happening is not feasible, but taking preventative measures can play a big part in preventing Legionnaires’ disease. To reduce risk undertake the following measures:
- Ensure there are no dead spaces or legs where water can stagnate
- Employ the use of pumps to keep water moving
- Reduce the temperature of the system and its sunlight exposure
- Regularly test the water and water vapour
- Regularly service and clean the system
- Treat the water with relevant materials to clean the water of bacteria (these must be safe materials)
Watch for the warning signs. Legionnaires’ is a severe form of pneumonia characterised by headache, high fever, chills, cough, chest pain, and shortness of breath. It is not spread from person to person. Most people exposed to the Legionella bacteria do not become ill, but the elderly, smokers, and people with chronic lung disease or weakened immune systems are more vulnerable. If people that are spending time in a environment are suffering from any of these symptoms it is prudent to have them assessed for infection.
Determine if you should perform routine testing. The water management team should consider whether testing must be performed. In any case regular testing is not required, but is recommended. The management team should determine the frequency, location, and plans for the testing.
Develop a plan if Legionella is found. If you test and find Legionella, you should have a plan in place to remove the bacteria from the system. Facility managers should have all personnel evacuate the building and shut down the HVAC system. Environmental technicians suited in specialised protective garments and personal protective equipment will have to enter the building and disinfect the HVAC system.
Why test for legionnaires disease
Testing procedures are ultimately the only way to show if temperature, disinfection, chlorination, or other methods of controlling Legionella are actually working.
Testing methods are typically integrated in a strategic manner depending on critical control points within the building, and will depend on the speed, cost, and specificity of the questions being asked or areas being targeted with respect to exposure or contamination. Laboratories performing the test shall be proficient in the CDC’s Elite Program in order to support the validity of the testing regimen.
DNA methods have emerged in recent years and may prove extremely useful in evaluating Legionella species present, and in shortening the time between sampling and the receipt of laboratory reports.
Jaymak can help you keep your business mitigate the risk presented by Legionnaires bacteria
Jaymak is a national franchisee network that provides professional cleaning and hygiene services including the cleaning, santising and maintenance of all air conditioning units, water testing and air-cooling towers.
We are the only Australian ISO accredited food servicers provider, and we are very proud of this status. It sets us apart from all other hygiene and cleaning specialists in the Australian marketplace. After gaining ISO 9001/22000 accreditation in 2006, we have expanded our food safety management systems and has provided us with the ability to provide a unified national and international standard in hygiene cleaning for all of our clients.
By regularly servicing your facilities and assets with us you are acting to place preventative measures in place so that your business is free from the risk of Legionnaires, and other harmful bacteria.
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