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What is Legionnaires' Disease and How Can FM's Combat It?

Legionnaires’ disease has been making headlines recently as outbreaks have been increasing worldwide. In the most recent case, Disneyland guests became infected. What is this disease, and why is it an important subject for all facility managers?

This type of disease is the result of a specific type of bacteria that is extremely common. In one CDC study, the bacteria was present in 84 percent of 200 tested cooling towers. Facility managers need to be aware of this potentially devastating disease and how to prevent an outbreak.

Legionnaires’ Disease

Legionnaires’ disease is a severe, pneumonia-like respiratory disease that is caused by exposure to Legionella bacteria. This type of bacterium is naturally present in freshwater, but it can become a problem when it spreads in man-made freshwater areas. Common areas where legionella buildup occurs include showers, faucets, decorative fountains, hot tubs, large plumbing systems and cooling towers. People become infected when they inhale minuscule water droplets containing legionella. Once infected, a person cannot typically spread the disease to others.

Symptoms of infection usually become apparent within the first two weeks of being exposed to the bacteria. Legionnaires’ disease closely resembles pneumonia. Victims of this disease commonly experience fever-like symptoms, cough, muscle aches, shortness of breath and headaches. Less commonly, those infected will suffer from nausea, confusion and diarrhea. Doctors will need to perform a urine test or phlegm sample test to determine if legionella is causing the lung infection, and antibiotics are necessary for successful recovery. While this condition is rare, experts estimate that a large number of legionnaires cases are misdiagnosed by medical professionals. 

Recent Concerns

The Legionella bacteria strain was discovered after a devastating outbreak in 1976. The incident killed 34 people who had all attended an American Legion convention. When researchers discovered the bacteria that was causing the infection, they positively linked the bacteria to the previously mysterious Pontiac fever. Legionella outbreaks are still fairly rare, but there has been an uptick in recent cases. Just last month, an outbreak of the disease in a Lisbon hospital killed four and infected at least 40. Six individuals required intensive care, and most of the victims were either elderly or had chronic conditions. Experts are still working to determine the source of the bacteria.

Around the same time, Disneyland in Anaheim was forced to shut down after several cases of Legionnaires’ disease became apparent after visiting the theme park. After nine different guests reported the condition, Disneyland conducted an investigation. Around a month before the outbreak, an elevated level of legionella bacteria was found in two cooling towers located in a backstage area. Both towers had been treated, disinfected and re-opened, but Disneyland took the towers out of service again when the health agency ordered them to shut down.

The health agency also alerted healthcare providers to be aware of the outbreak in any patients that visited Anaheim or Disneyland. Orange County has recorded over 55 cases of Legionnaires’ disease this year alone.

How Facility Managers Can Prevent an Outbreak

The key to preventing a legionnaires’ disease outbreak is being proactive in testing water systems for the bacteria. Legionella flourishes best in warmer water. Disinfectants that are necessary to kill Legionella are harder to maintain in warmer temperatures, so hot tubs are one of the biggest breeding grounds.

Facility managers need to be aware that their facility’s cooling towers are extremely vulnerable to a buildup of legionella. Cooling towers hold warm water that eventually evaporates into the air, and these conditions are exactly how many outbreaks begin. The buildup of bacteria in cooling towers were most likely responsible for the severe legionnaires’ outbreaks in Portugal (2014), New York (2015), and Disneyland (2017). In addition to heat, stagnation, sediment and micro-organisms in a water supply all support the growth of this bacteria.

OSHA suggests choosing a high-efficiency eliminator design for cooling towers to control growth. OSHA additionally suggests that periodic maintenance and inspection, the use of biocide, frequent cleanings and record keeping are all crucial steps in preventing a legionnaires’ disease outbreak.

While outbreaks of legionnaires’ disease have been rare, incidents have been increasing world-wide in recent years. Much of this increase can be attributed to an increased awareness of the condition and better testing methods. An individual’s likelihood of becoming infected with the legionella bacteria has a lot to do with both the level of exposure and the individual’s susceptibility to disease. The bacteria is very common in hot-water sources, and it needs to be controlled. According to OSHA surveys, around 60 percent of the 1,000 cooling towers tested contained non-detectable levels of the bacteria.

As a facility manager, it’s crucial to understand that the best way to prevent an outbreak is to closely maintain and inspect water sources that are susceptible to the bacteria.

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