The number of cases of the deadly Legionnaires' Disease have quadrupled due to bad water management, a new study by the Centers for Disease Control warns.
According to the CDC’s "Vital Signs" report report:
- The number of people with Legionnaires’ disease grew by nearly 4 times from 2000–2014.
- Legionnaires’ disease is deadly for about 10% of people who get it.
- Almost all (9 in 10) outbreaks were caused by problems preventable with more effective water management.
“Legionnaires’ disease is on the rise,” the CDC warns, noting that about 5,000 people were diagnosed in the past year with the deadly lung infection from more than 20 outbreaks caused by “breathing in small droplets of water contaminated with Legionella.”
Approximately 80% of Legionnaires’ disease outbreaks that CDC investigated from 2000 through 2014 occurred in hotels, long-term care facilities, and hospitals. Most Legionnaires’ disease outbreaks CDC investigated occurred because water systems in buildings were not well-maintained.
The most common source of building-associated Legionnaires’ disease outbreaks was drinkable water (56%), such as water used for showering, followed by cooling towers (22%), and hot tubs (7%). Other sources included industrial equipment (4%) and a decorative fountain/water feature (4%).
In nearly half of cases, more than one type of water management failure was identified. Descriptions of failures that contributed to the outbreaks show:
- About 2 in 3 (65%) were due to process failures, like not having a Legionella water management program.
- About 1 in 2 (52 percent) were due to human error, such as a hot tub filter not being cleaned or replaced as recommended by the manufacturer,
- About 1 in 3 (35 percent) were due to equipment, such as a disinfection system, not working.
- About 1 in 3 (35%) were due to changes in water quality from reasons external to the building itself, like nearby construction.
CDC is urging building owners and managers to follow newly published standards that promote water management programs aimed at reducing the risk of Legionnaires’ disease. To support building owners and managers in this, CDC released a toolkit on Developing a Water Management Program to Reduce Legionella Growth & Spread in Buildings: A Practical Guide to Implementing Industry Standards.
The CDC report examined 27 building-associated Legionnaires’ disease outbreaks investigated by CDC across 24 states and territories, Mexico, and Canada. For each outbreak, CDC researchers recorded the location, source of exposure, and deficiencies in environmental control of Legionella.
