Hand hygiene is one of the simplest and most effective ways to reduce the spread of germs. Yet for years, many people assumed that waterless hand sanitizers offered the same level of cleanliness as washing with ordinary soap and water. In 2005, researchers highlighted an important distinction: while alcohol-based sanitizers can be highly effective in many situations, plain soap and water remain the gold standard when hands are visibly dirty or contaminated. The findings helped reinforce a public health message that has become even more relevant in the years since. Washing hands is not just about killing germs—it is also about physically removing dirt, oils, chemicals, and microorganisms that sanitizers alone may leave behind.
The science begins with understanding what happens to our hands throughout the day.
