Frequent hand washing is the best line of defense against illness and the spread of germs, both at home and in public institutions, such as hospitals and schools, says the Centers for Disease Control and Prevention. When viruses and bacteria hitch a ride on unwashed hands, the result can range from a benign cold to an infectious disease.
Function
Unlike cleansers that contain an antibacterial agent, plain soap and water do not kill germs on hands. Instead, the soap attaches to the dirt and other materials on your hands, and then the water sweeps them away. Viruses, fungi and bacteria stick to the oils and dead skin that are always present on hands. When the soap molecules surround them, the oil and dead skin--and the germs that have attached themselves--lose their hold and go down the drain, taking with them the potential for illness.
Method
Using soap and water remains the best way to keep hands clean. The Mayo Clinic recommends this method of proper hand hygiene: Wet your hands under running water, then apply the soap, lathering well. Rub your hands together for at least 20 seconds, not neglecting the wrists or the areas between your fingers and underneath your nails. Sing the "Happy Birthday" song to yourself twice to approximate the correct time for lathering, the Centers for Disease Control says. Rinse the soap off completely and then dry your hands with a paper towel or air dryer.
Time Frame
Wash your hands immediately after going to the bathroom, changing a diaper or dealing with animal waste, blowing your nose, handling the garbage or other potentially germ-ridden items, treating wounds or touching someone who's ill or handling raw meat, says the Mayo Clinic. Wash your hands before making a meal or eating, tending a sick or injured person and putting in or taking out contact lenses.
Significance
A study published in the Lancet medical journal in 2005 involved promoting hand-washing in households in Pakistan in an effort to reduce cases of diarrhea and lower respiratory infection, which kill millions of children under 5 worldwide every year. Some households were given plain soap and some antibacterial soap; all were visited by researchers who recorded the incidence of illness and encouraged the inhabitants to wash their hands often. Children under 5 in these households had only half as many cases of diarrhea and pneumonia as children in households where hand-washing was not promoted. The kind of soap did not make a significant difference, researchers said.
Considerations
If soap and water are not available, alcohol-based hand sanitizers provide a solution, making quick work of killing most germs. Read the label to be sure the sanitizer contains at least 60 percent alcohol, and apply the gel liberally when you use it. LiveScience.com points out that soap and water should be the first choice, especially in bathrooms and kitchens, because alcohol cannot clean organic matter off your hands and does not work well on a few food-borne germs such as E. coli.
