Many food-borne pathogens such as Shigella, Escherichia coli, Salmonella and Hepatitis A can hitch a ride on hands. Food-safety experts do not consider it compulsive for parents or anyone caring for small children to wash their hands eight to ten times a day. If you are not changing diapers, you probably ought to be washing your hands five or six times daily, more if necessary. Whenever possible, use liquid soap from a pump bottle or wall-mounted dispenser. Bacteria have been shown to grow on bar soap.
Thorough hand drying is probably as important as hand washing to prevent food-borne illness.
Researchers at Auckland Hospital in New Zealand have demonstrated that rinsed but undried hands can transfer tens of thousands of bacterial cells to food. A fresh paper towel is more hygienic than a cloth towel that is damp or has not been recently laundered. Hot air dryers are efficient in theory, but people rarely use dryers long enough. The same New Zealand researchers showed that ten seconds of drying with a cloth towel removed 96 percent of the water from a person's hands, but it took forty-five seconds to achieve this level of dryness using an air dryer. Often, people complete the hot air-drying process by wiping their hands on their clothes, or they apply makeup and comb their hair while their hands are still moist, studies have shown.