LiquiTech Blog

The History of Legionnaires’ Disease: How We’ve Come to Understand it

Legionnaires’ Disease is a severe form of pneumonia that sickens about 18,000 people in the U.S. each year. It’s caused by the bacterium Legionella pneumophila. Scientists first identified it in 1977. That was six months after a mysterious outbreak sickened 180 and claimed the lives of 29 people attending an American Legion convention at a Philadelphia hotel.


The CDC estimates that as many as 18,000 people are hospitalized annually with the disease. In most cases, it can be treated successfully with a regimen of antibiotics, and the majority of patients recover as long as it is caught early enough.

The source

The source of this disease is the bacterium Legionella pneumophila, found in both potable and nonpotable water systems. Legionella causes include inhaling or aspirating small droplets of water contaminated with the bacteria.


Legionella bacteria trigger pneumonia. The most typical signs and symptoms of Legionnaires’ Disease include a high fever, chills, cough, muscle aches, and headaches. Generally, there is a two to ten day incubation period before the first Legionella symptoms present themselves.

Long-term effects

Studies have shown long-term effects such as the persistence of fatigue, neurologic symptoms, and neuromuscular symptoms months after contracting the disease.


Smokers, the elderly, and those with chronic lung disease or suppressed immune systems are more likely to become infected, but healthy people may also be at risk.


Keeping Legionella out of water systems in buildings is key to preventing infection. LiquiTech® Copper-Silver Ionization has proven to be one of the most effective technologies for controlling Legionella in water systems.

The importance of protection

Countless public-facing businesses count on their water systems to be clean and free from contamination. Their patrons and guests trust them to have the safest and cleanest water systems to prevent outbreaks of this disease and other illnesses. However, these operations present an inherent Legionnaires risk if they do not have a solid prevention and mitigation plan.

For example, hotels and health clubs typically feature hot tubs, saunas, and swimming pools. These all have the potential to release water vapor into the air that can carry bacteria. Hospitals and other healthcare facilities house people with compromised immunity who may contract waterborne diseases more easily. Hotel air-conditioning systems and ice makers can generate condensation that allows pathogens to collect and breed, making them one of the most common causes of Legionnaires’ Disease.

All these properties and many more must have a robust protocol of testing and water treatment to prevent outbreaks. The experience, expertise, and technology LiquiTech brings to the table make us the ideal provider for supplying complete risk assessment. We have not only the capability to monitor your infrastructure for indicators of contamination but also the mitigation strategies to eliminate them.

We serve a diverse cross-section of industries, which means we understand how to deal with a wide variety of environments and their unique challenges. Learn more about our water safety solutions for building water systems.

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