Handwashing to prevent the flu: What water temperature and how long?

Most of you should be aware, by now, that frequent hand washing not only helps protect you from the flu, but also a variety of other potential infections. It also helps, if you are carrying a disease, to prevent you from spreading it to others. But, should you use hot water or not? And, how long should you wash your hands? How much is enough?As to the temperature of the water, a new report suggests that hand-washing with hot water may not be more effective in reducing disease.

The New York Times “Really?” column reports, “With swine flu sweeping across the country, health officials are reminding Americans to wash their hands often to reduce the spread of the disease. … However, there has been much debate about whether hot water was really more effective than cold.”

According to the FDA, “hot water comfortable enough for washing hands is not hot enough to kill bacteria.” It is, however, “more effective than cold water because it removes oils from the hand that can harbor bacteria.”

But in 2005, researchers “found no evidence that hot water had any benefit, and noted that it might increase the ‘irritant capacity’ of some soaps, causing contact dermatitis.”

As to how long to wash your hands? About as long as it takes to sing or hum “Happy birthday to you, happy birthday to you, happy birthday dear swine flu. Happy birthday to you.”

Most everyone knows the song and it’s about the right amount of time.

So, what do I recommend? Just wash your hands frequently, choose a comfortable water temperature (hot, warm, or cold) and hum “Happy Birthday” as you lather.

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