What action should be taken if Legionella is found in a sample from a Whirlpool spa?

The most appropriate course of action when Legionella is detected in a sample from a Whirlpool spa is to continue the current operation and maintenance program but with increased water temperature. This is based on the understanding that Legionella thrives in warm water environments, typically in a range from 77°F to 113°F. Operating the spa at a higher temperature can help to inhibit the growth of Legionella.

It's important to note that simply closing the spa might not address the underlying problem of Legionella presence. Closing the spa could be a temporary solution, but does not contribute to eliminating or managing the bacteria effectively over time.

On the other hand, removing all water and disinfecting the spa is an extreme measure. While disinfection is necessary, it must be part of a broader strategy, including assessing and improving ongoing water management practices.

Reducing the water temperature is counterproductive. Lower temperatures would actually create a more favorable environment for Legionella growth rather than mitigate the risk. The focus should be on maintaining water conditions that suppress the growth of the bacteria while implementing comprehensive water management protocols.