|Articles|March 8, 2016

Legionnaires' Disease: Know the Risk and Learn Proper Prevention Methods

Author(s)Sarah Anwar

As has recently been seen in Flint, MI, it is vital to know the risk for this deadly disease and the steps to take to prevent Legionella bacteria from flourishing.

Legionellosis, a disease caused by the bacteria, Legionella, affects the respiratory system and can cause pneumonia. Not to be confused with Pontiac fever, which is caused by the same bacteria but manifesting symptoms similar to the flu, Legionnaires’ disease presents severe symptoms. Legionella is natural in fresh water, however, its limited number prevents the cause of disease. Nonetheless, the amount of Legionella is intensified in man-made water systems, specifically warm water sources (like large plumbing systems, fountains, cooling towers, and hot tubs), which can lead to a Legionnaires infection via aerosolization. Additionally, the bacteria can be transmitted with the intake of regular drinking water through the trachea and lungs as opposed to the digestive tract, such as the case in individuals with swallowing difficulties. Interaction with an individual infected with Legionnaires’ disease is not cause for alarm since the disease is not communicable through direct contact.

Symptoms of Legionnaires’ disease

An individual usually presents the following symptoms of illness from the second to the tenth day of infection:

  • Coughing
  • Shortness of breath
  • Fever
  • Muscle aches
  • Headaches

Legionnaires’ in Flint

It is vital to take the necessary steps for Legionnaires’ prevention, since it can be a fatal disease, as has recently been seen in Flint, Michigan.

In 2013, when the decision was made to switch the city’s source of water from the Detroit Water and Sewerage Department to the Karegnondi Water Authority (KWA), which would provide water from Lake Huron, Flint was given an ultimatum that if they signed a contract with KWA, Detroit would cut off water after one year. This presented a dilemma since KWA would only start supplying water to Flint in 2016. Nonetheless, the state-appointed official decided to proceed with the plans, since it was the “financially responsible alternative water source,” states the city’s website. In the meantime, it was decided that the Flint River would be the main source of water until the switch to KWA.

Since the use of the Flint River as a water source, 87 individuals were diagnosed with Legionnaires’ disease, and 9 resulting deaths were reported. Government agencies have yet to take initiative to test Flint River for a correlation between it and the Legionella strains found within the infected populace, although there is evidence of contamination: the water contains unhealthy amounts of lead, which caused a jump in lead poisoning in the city’s children, according to Dr. Mona Hanna-Attisha, a pediatrician at Hurley Children’s Hospital in Flint. Without such tests, it is difficult to determine whether or not the water is the cause for the Legionnaires outbreak.

Prevention

Unfortunately, there is no vaccine for Legionnaires’ disease; prevention boils down to hindering bacteria colonization in water systems, through proper maintenance procedures. The Centers for Disease Control and Prevention (CDC) warn that, “low water volumes combined with high temperatures and heavy bather loads” make public hot tubs a magnet for Legionella. The upkeep of proper disinfectant and pH levels needed to kill the bacteria is essential (2-4 parts per million [ppm] of free chlorine, 4-6 ppm of bromine, and a 7.2-7.8 pH level). Checking these levels twice a day (and even more so when the hot tub is being used by a large quantity of people) is vital to preventing Legionnaires’. The American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) has developed standard guidelines for building owners and managers who maintain building systems to aid in the prevention of Legionnaires.

Although the state began supplying free water filters to all Flint homes on October 2, 2015, and switched back its main water supply to Detroit, high levels of lead were still evident in the city’s tap water. The National Guard commenced water filter and bottled water distribution among the city’s residents in January, however, it is important for those who are at high risk for Legionnaires’ to contact their primary healthcare professional to get tested for the disease.


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