After flu shot, hand washing best defense against winter illness CHARLOTTE, N.C., Jan. 20 (UPI) -- With this year's flu epidemic in full force, U.S. hygiene experts urge everyone to step up how often and how effectively they wash their hands. The U.S. Centers for Disease Control and Prevention says the single best way to prevent seasonal flu is to get vaccinated each year. Aside from the vaccine, however, proper hand washing is essential, said Paul Alper, vice president strategy and business development for DebMed and 30-year veteran of the hand hygiene industry, Alper said the right way to wash your hands is to: Wet your hands with clean, warn running water and apply soap. Rub your hands together to make a lather and scrub them well; be sure to scrub the backs of your hands, between your fingers and under your nails. Continue rubbing your hands for at least 20 seconds. Need a timer? Hum the "Happy Birthday" song from beginning to end, twice. Rinse your hands well under running water Dry your hands using a clean towel or air dry them. If soap and water are unavailable, use an alcohol-based hand sanitizer that contains at least 60 percent alcohol to clean hands, Alper said.