Hot tub lung: Am I at risk?

What is "hot tub lung"? How can I prevent it?

- John / Indiana

Answer

"Hot tub lung" is an uncommon infection or allergic reaction of the lungs due to inhaling the bacterium Mycobacterium avium (M. avium) from a hot tub. M. avium belongs to the same class of bacteria that cause tuberculosis, but it's not contagious.

Hot tubs provide an ideal environment for the growth of bacteria, such as M. avium. Bacterial growth is more likely to occur in tubs that aren't cleaned as often as recommended. Also, added chlorine loses most of its disinfectant properties at temperatures above 84 F (29 C).

The bacteria get into your lungs when the bubbling hot tub water evaporates. The bubbles rise to the surface, burst and disperse the bacteria into the air. Hot tub lung can be easily prevented by properly maintaining your hot tub, or asking about the maintenance of hot tubs at spas or hotels.

The Centers for Disease Control and Prevention recommends these guidelines for the proper treatment and maintenance of water in hot tubs:

• 2 to 5 parts per million (ppm) of chlorine
• 7.2 to 7.8 pH level

During operation, test the water frequently. Also, clean the system and change the water once a month or more often according to the manufacturer's recommendations.

When using a hot tub you don't maintain, you can ask:

• To see records of the most recent health inspection of the hot tub
• If the chlorine and pH levels of the hot tub are checked at least twice daily
• If chlorine and pH levels are checked when the hot tub is most heavily used
• If the maintenance staff of the pool has had specialized training to operate a hot tub

If you do not believe a hot tub has been properly maintained, don't enter it. Even with proper precautions, there is still a small risk you could become infected. Signs and symptoms of M. avium infection usually include:

• Shortness of breath
• Fatigue
• Fever or chills
• Wet cough
• Tightness in the chest

Your doctor may make a diagnosis of hot tub lung based on:

• Chest X-rays
• Computerized tomography (CT) scans of the lungs
• Removal of lung tissue (biopsy) for microscopic examination and culture

Treatment of hot tub lung includes:

• Discontinuing use of the hot tub
• Corticosteroids
• Supplemental oxygen, in severe cases

The role of antibiotics in the treatment of this condition is controversial. In many cases, the inflammation seems to be a hypersensitivity reaction that improves without antibiotic treatment.