|MadSci Network: Microbiology|
Most tests of antibacterial soaps have looked at the bacteria that are naturally on skin, rather than bacteria that cause disease. Killing normal skin bacteria may not favor disease prevention — there is some difference of opinion about this. Disease bacteria are probably killed pretty well by the antibacterial ingredients in soaps; however, other kinds of disease agents, such as viruses and protozoa, are fairly resistant. I don't really think much gets transmitted from person to person on the bar of soap, but disease agents (not just "germs," which are mostly harmless) need to be removed from the skin in washing; it is not absolutely necessary that they be killed in the process. It is important to wash hands after using the toilet and before eating. People who prepare food for others to eat should wash their hands before beginning and often while they work, especially after handling raw meat or poultry, and maybe even after handling raw vegetables. Recently published tests again seem to suggest that careful use of regular soap and water, making sure to rub all over the hands and rinse carefully, probably does as good a job as is needed. Some say you should spend at least 20 seconds on this. Others think that drying the hands afterward is also important — I'm not exactly sure why. At least, if you are preparing food, you should probably dry your hands on a paper towel or a cloth towel that has only been in contact with clean hands. Most important, if you are doing something that requires frequent hand washing, is to use a soap that doesn't irritate the skin. If your skin gets irritated by the soap, you are less likely to wash as often as you should. Antibacterial soaps aren't a substitute for thorough washing, and because not all disease agents are bacteria, it's washing that is most important.
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