in a room adjacent to the family’s indoor pool. The family had recently converted the pool’s sanitation regime to UV and hydrogen peroxide. Subsequent analysis of the pool water found M. intracellulare, as well as M. avium and M. marinum. The boy was admitted to the emergency room with severe difficulty breathing and required supplemental oxygen.

Ultimately, his entire family contracted the disease, but after treatment, they were cured.

A follow-up medical visit two years later showed that their respiratory symptoms were gone, although they did show mild but possibly permanent lung damage.

In 2013, a study was published in the European Respiratory Review that identified hot tub lung as “an occupational hazard.” In the article, the authors presented seven separate NTM cases of people (ages 30 to 64) whose job it was to clean hot tubs at three different hotels. Five of the workers became very sick while two were totally asymptomatic but tested positive for M. avium.

The three spa facilities were similar in construction and maintenance. They all used UV light and hydrogen peroxide as disinfectants, and the workers all cleaned the nylon-sheet particle filters with pressure washers.

All of the workers recovered spontaneously without antibiotics or corticosteroids when the filters were replaced with sand filters and the pressure washing stopped.

The authors of the study recommend that pressure washing filters should be avoided.

It is important to note that in the U.S., chlorine and bromine are the preferred and recommended sanitizers so as to maintain a constant sanitizer residual, and UV or ozonebased disinfectants are recommended to be used on a secondary and/or supplemental basis.

Furthermore, such a pool or spa with a constant halogen-based residual prevents the formation of the biofilms that harbor the disease in pools and spas.