Where is legionella found

Most people catch Legionnaires' disease by inhaling the bacteria from water or soil. Older adults, smokers and people with weakened immune systems are particularly susceptible to Legionnaires' disease. The legionella bacterium also causes Pontiac fever, a milder illness resembling the flu. Pontiac fever usually clears on its own, but untreated Legionnaires' disease can be fatal. Although prompt treatment with antibiotics usually cures Legionnaires' disease, some people continue to have problems after treatment.

Legionnaires' disease usually develops two to 10 days after exposure to legionella bacteria. It frequently begins with the following signs and symptoms:.

Although Legionnaires' disease primarily affects the lungs, it occasionally can cause infections in wounds and in other parts of the body, including the heart.

A mild form of Legionnaires' disease — known as Pontiac fever — can produce fever, chills, headache and muscle aches. Pontiac fever doesn't infect your lungs, and symptoms usually clear within two to five days. See your doctor if you think you've been exposed to legionella bacteria. Diagnosing and treating Legionnaires' disease as soon as possible can help shorten the recovery period and prevent serious complications.

For people at high risk, such as smokers or older adults, prompt treatment is critical. The bacterium Legionella pneumophila is responsible for most cases of Legionnaires' disease. Outdoors, legionella bacteria survive in soil and water, but rarely cause infections.

However, legionella bacteria can multiply in water systems made by humans, such as air conditioners. To do this, Legionella first has to grow increase in numbers.

Then it has to spread through small water droplets aerosolization that people can breathe in. You can take steps to reduce the risk for Legionella in your building.

A variety of internal and external factors can lead to a Legionella problem in your building, including. When there is a reduction in disinfectant levels in your building water systems, Legionella can grow. In some buildings, processes such as heating, storing, and filtering can reduce the amount of available disinfectant, allowing Legionella to grow if steps are not taken to stop it.

Your building water supply may need long-term supplemental disinfectants added to the water to boost the level of disinfectant and help limit Legionella growth. Examples of disinfectants include chlorine, mono-chloramine, chlorine dioxide, ultraviolet light, and ozone. To keep water outside the range for Legionella growth, it is important to keep cold water cold and keep hot water hot.

When water does not flow well, the resulting areas of stagnation encourage biofilm growth, reduce water temperatures to levels that allow Legionella to grow, and reduce levels of disinfectant.

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