NEW YORK (Reuters Health) - Better think twice before soothing those aching muscles in a whirlpool bath or hot tub. A new study shows that whirlpool bathtubs can be a breeding ground for a host of disease-causing bacteria.
Dr. Rita B. Moyes a microbiologist at Texas A & M University tested 43 water samples from both private and public whirlpool bathtubs. "Every tub tested had some kind of microbial growth," she told Reuters Health.
"And I was just getting the few organisms I was testing for, so it is probably just the tip of the iceberg as far as what is really present. Also, I did no viral testing," Moyes emphasized.
In 95 percent of the tubs, bacteria derived from feces were present, while 81 percent had fungi and 34 percent contained potentially deadly staphylococcus bacteria.
Moyes explained that a teaspoon of normal tap water contains about 138 bacteria and many samples are bacteria-free. A teaspoon of whirlpool tub water, on the other hand, contains an average of more than 2 million bacteria.
The interior pipes of whirlpool baths that are not filtered or chemically treated, and non-maintained hot tubs, are prime areas for potentially infectious microbes to congregate and grow, Moyes noted. These organisms often form a biofilm - a community of organisms, which work together and are more resistant to cleaners.
When the jets are switched on, the bacteria-packed water gets blown into the tub. "Due to the movement of the water, an aerosol is created that carries these organisms down into your lungs or other orifices - something that doesn't happen in a regular tub," Moyes explained.
The bacteria found in whirlpool baths can lead to a number of diseases, including urinary tract infections, skin infections, and pneumonia.
So who is most at risk? "Of course the young and the old and the immunocompromised should not be exposed, including breathing in the aerosol from outside the tub," Moyes said.
"A chemically maintained hot tub should not be a problem to a healthy person but if you are having recurring infections, consider the tub as a potential source," she added. Moyes' research is published in an online journal called PM Engineer.