Science-- there's something for everyone

Wednesday, April 7, 2010

To avoid the common cold, use hand sanitizer

Ronald Turner, Janice Fuls and Nancy Rodgers of the University of Virginia School of medicine tested whether alcohol based hand sanitizers were better than plain ol’ soap and water for avoiding the common cold. They found that hand sanitizers were significantly more effective against at least one cause of colds.

About a third of all colds are caused by rhinoviruses. The researchers contaminated the hands of healthy volunteers with these viruses, and then asked them to follow one of several different hand washing protocols, including no treatment, using plain water, using soap and water, and using hand sanitizer. Hand sanitizer removed 80% of rhinoviruses, whereas soap and water only removed 30%. Adding organic acids (such as lactic acid) to the ethanol-based sanitizers gave even more protection, killing the viruses for up to four hours.

I have to admit that I was surprised by this result. Of course, you have to use the hand sanitizer properly. Here are the guidelines for using hand sanitizer from the Mayo Clinic:

  • Use a product that is at least 60% alcohol
  • Apply enough of the product to wet your hands completely
  • Rub your hands together, covering all surfaces (including under your nails) for up to 25 seconds, or until completely dry.
  • And of course, if your hands are visibly dirty, go back to soap and water!