🛁 Outdoor Hot Tubs & Aspergillosis — The Key Issues

For someone with aspergillosis (especially chronic pulmonary aspergillosis or ABPA), **outdoor hot tubs are usually not recommended — or at the very least, should be approached with serious caution.

❗ 1. Fungal Exposure Risk (including Aspergillus):

• Hot tubs — even well-maintained ones — are prone to harbouring fungal spores, biofilms, and moulds, especially in:

  • Filters and jets

  • Under the covers and around the edge

  • The aerosolised mist from bubbles and heat

• Aspergillus and other moulds can thrive in warm, damp, organic-rich environments — exactly what a hot tub is.

❗ 2. Risk of “Hot Tub Lung” (hypersensitivity pneumonitis):

• Caused by inhalation of waterborne organisms, especially Mycobacterium avium and fungal spores.

• Can mimic or worsen chronic lung conditions and is dangerous in someone with underlying aspergillosis.

⚠️ 3. Chlorine or Bromine May Not Be Enough:

• While disinfection kills many bacteria, fungal spores and biofilm-forming organisms can persist — especially in jets or hard-to-reach areas.

🟡 If a patient insists on using a hot tub, they should:

• Only use tubs maintained to hospital-grade cleanliness standards (rare in private settings)

• Avoid if there’s any cover of mould, visible residue, or musty smell

• Use during off-peak times to reduce aerosol exposure

• Avoid placing head near water jets or breathing in rising steam

• Limit time in the tub and shower immediately afterward

• Consider wearing a high-grade mask while near the tub when not submerged

✅ Safer Alternatives for Relaxation:

• Dry saunas (if tolerated)

• Warm baths indoors in clean, ventilated bathrooms

• Gentle hydrotherapy pools with strict water quality controls

🔍 Summary:

For someone with aspergillosis, outdoor hot tubs are generally not recommended due to the risk of fungal aerosol exposure and potential lung flare-ups. Even “clean” tubs can harbour hidden risks.