Legionnaires’ disease outbreaks investigated by the CDC typically reveal:
- About 2 in 3 (65%) are due to process failures, like not having a Legionella water management program.
- About 1 in 2 (52%) are 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%) are due to equipment, such as a disinfection system, not working.
- About 1 in 3 (35%) are due to changes in water quality due to reasons external to the building itself, like nearby construction.
- About 1 in 2 (48%) are due to more than one of the above problems.