Legionella the Overwhelming Cause of Hospitalizations and Deaths in Drinking Water Disease Outbreaks
Waterborne disease outbreaks in the United States are not uncommon, with dozens reported each year. These outbreaks have hundreds of contributing factors, but Legionella is by far the greatest cause of both hospitalizations and deaths. According to the CDC’s National Outbreak Reporting System (NORS) summary of six years, Legionella accounted for 97% of all hospitalizations and 98% of all deaths. CDC also states that 9 out of 10 Legionella outbreaks could likely be prevented with a good Legionella water management program paired with Legionella testing.
The severity of a Legionella outbreak was particularly notable given that the study looked at drinking water outbreak causes that included those associated with biofilms, enteric illnesses (viruses, bacteria, and parasites), and chemicals or toxins. In total, the outbreaks were identified to have 454 contributing factor types.
While enteric illnesses associated with viruses, bacteria, and parasites accounted for the majority – 61% – of all illnesses, but only 2% of hospitalizations, and no deaths.
In contrast, biofilm-related outbreaks were far more serious, and Legionella alone accounted for 97% of the hospitalizations and 98% of the deaths. Moreover, the study found that Legionella-associated outbreaks were increasing in number over time.
Outbreak reports cited the premise or point of use location most frequently as the contributing factor for Legionella and other biofilm-associated pathogen outbreaks with the leading contributing factors that were reported 2% or more of the time being:
- Legionella species in the water system
- Legionella-promoting water temperatures and chlorine levels within the potable water system inside the building
- Water temperature greater than 86 degrees F
- Aging plumbing components (e.g. pipes, tanks, or valves)
- Deficiency in building or home-specific water treatment after water meter or property line
- Contamination at point of use (tap)
- Legionella-promoting chlorine levels within the potable water system inside the building
- Temperature control in hot water systems
- Deficiency or contamination of equipment or devices using or distributing water
- Contamination of plumbing during construction or repair
- Stagnation of water because of sporadic occupancy
The report concluded that primary prevention of Legionella-associated outbreaks through biofilm control and water management remains critical in healthcare and non-healthcare settings.
Given the severity of Legionella-related waterborne disease outbreaks associated with drinking water, every facility must have a well-defined, up-to-date water management plan, regular testing, and proper mitigation and remediation of Legionella. The independent, certified Legionella control experts at Legionella Control Systems can provide expert guidance to help you protect your facility occupants. Contact them right now at info@legionellacontrolsystems.com or 888-416-8626.
