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Relax, your shower head won't hurt you Add to ...

Some health scares just aren't worth fretting about. Take, for example, this week's news that the shower head in your bathroom may be harbouring potentially hazardous microbes.

University of Colorado researchers analyzed 45 showerheads from nine U.S. cities and found 30 per cent held a slew of bacteria, including "significant" levels of Mycobacterium avium, which is linked to respiratory infections.

According to the research team, led by Norman Pace, Mycobacterium avium and related pathogens were clumped together in slimy "biofilms" that clung to the dark, dank interior of the shower heads.

The findings, published in the Proceedings of the National Academy of Sciences, raise the possibility that water passing through the shower head could produce a spray of infected droplets, which can be inhaled into your lungs.

So should you be concerned about getting a bacteria blast with your morning shower? Even the researchers say healthy individuals have little need to worry. People are frequently exposed to this type of bacteria without ill effects.

But Dr. Pace indicated that those with compromised immune systems - such as AIDS patients, pregnant women and some elderly folk - may be at risk of getting an infection that produces a persistent dry cough, shortness of breath and general weakness.

However, other experts challenged the suggestion that immune-compromised individuals face significantly elevated odds of getting sick.

"These are not common infections even in the high-risk patient population," said Andrew Simor, head of microbiology and infectious diseases at Sunnybrook Health Sciences Centre in Toronto.

"Mycobacterium avium is widespread in the environment," he noted. "It's in the water supply; it's in the soil. So all of us are frequently exposed to the organism in our general environment - not just from shower heads."

Dr. Simor also pointed out that the University of Colorado scientists used a highly sophisticated means of detecting bacteria.

Normally, researchers will take a swab of a potentially contaminated site and then try to grow, or culture, the microbes in the lab. But in this case, they used relatively new techniques that can identify infinitesimally small bits of genetic material from the bacteria.

"The method they used is very powerful - no question about that. It will find more evidence of organisms than a standard culture. But the drawback to this method is that it may be too sensitive - it can actually pick up DNA from organisms that used to be there but are no longer viable," Dr. Simor said. In other words, the bacteria may be already dead.

The bottom line: Go ahead and enjoy a fret-free shower.

And if you're still feeling paranoid, check to see if you have a metal shower head. According to Dr. Pace, the microbes have a harder time growing on metal than plastic.

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