A friend of mine recently lost her security deposit at the holiday home she and her fellow hens were renting for a weekend. Why? Well, she dropped a microwaveable lasagne into the hot tub.

Could happen to anyone.

Despite trying their hardest to sieve out all the bits of minced beef and curdled white sauce that bubbled up to the surface, it was all in vain. The damage was done.

A stray lasagne might be the least of your holiday hot tub worries, though.

There may be a host of other nasties lurking invisibly in the water. Despite the potential wellbeing benefits of heat and hydrotherapy, enjoying a relaxing dip in the hotel hot tub could do more harm than good.

For example, it’s possible to contract a respiratory condition, colloquially referred to as hot-tub lung.

It’s triggered by microbes called mycobacteria, from the same family as those which cause the infection tuberculosis (TB).

Like in TB, hot-tub lung bacteria generate patches of inflammation in the lung tissue. This results in symptoms such as shortness of breath, cough and fever. The lung changes can be seen on an X-ray or CT scan of the chest, and may appear quite profound.

The hot tub acts as a perfect environment for........

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