Legionnaires’ Disease – so named because the disease was first observed among attendees of the American Legion convention in Philadelphia in 1976 – is a severe form of pneumonia caused by the Legionella pneumophila bacterium.
Legionella bacteria are often present in natural watercourses, but they can also multiply in any type of man-made water system, such as hot and cold water systems, cooling towers, spa pools, hot tubs, swimming pools, emergency showers, indoor ornamental fountains, and even the mist sprayers used in the produce section of grocery stores. These water systems are often used in large buildings like apartment complexes, hotels, hospitals, nursing homes, universities, and cruise ships, among many others.
The infection is often acquired through the inhalation of aerosolized water droplets, such as those produced by air conditioners, or through aspiration of contaminated water, such as when a person chokes on water in a hot tub or pool. The disease cannot be spread through direct person-to-person contact.
Most outbreaks of Legionnaires’ Disease occur in workplaces and large buildings because the water systems in place often provide favourable conditions for the growth and spread of the legionella bacteria. This is why it is the critical responsibility of employers and/or people who are responsible for the building’s maintenance to perform risk assessments of their water systems, control these risks, and properly maintain their systems to ensure the health and safety of people who frequent, work, or reside in the building.
Employers and/or building management are obligated to take precautionary measures to protect workers, residents, and the public from any risk of exposure to legionella bacteria. Their duties and obligations, with regards to legionella, include: identification and assessment of risks; formulating a course of action to prevent or control risks; implementing and overseeing the risk prevention or risk control plan; keeping records of and regularly checking the effectiveness of the implemented course of action; notifying the people/company that provided and maintain the water system; and reporting any suspected outbreaks to the proper authorities as well as notifying workers, residents, and the public about the same.
Depending on the results of the risk assessment, implementation of preventive or control measures may include: water treatment; regular disinfection of the water system; designing, maintaining, and operating the water system so that growth and spread of legionella are prevented or controlled; keeping water hot while also taking measures to prevent burns; conducting regular water sampling; and/or using alternative water systems.
Through proper measures, legionella outbreaks can be prevented or controlled effectively. Risk assessment and implementation of preventive or control measures are especially important in places that house, or regularly receive people, who have an increased risk for infection and fatality from the disease, particularly the elderly and patients with very poor health and compromised immune systems – hospitals and nursing homes, for example, are considered high risk areas.
Individuals can reduce their risk if exposed to Legionella bacteria by staying healthy and keeping their immune systems strong. Smoking must be avoided as this increases a person’s risk of developing Legionnaires’ Disease when exposure to legionella bacteria has occurred.
Aqua Scotland are a leading water treatment specialist based in Livingston in the central belt of Scotland. for more information about Legionella call us on 01506 430164.