On a molecular level, soap molecules disrupt the fatty layer or coat that surrounds the virus, once the external viral coat is broken down, the virus is no longer able to function. The soap molecules need some time to react with the viral coat and break it up. That is why it is recommended to lather soap and water by rubbing your hands thoroughly for a minimum of 20 seconds each time you wash our hands.
According to the CDC, handwashing is one of the best ways to protect yourself and your family from getting sick. Wash your hands often with soap and water for at least 20 seconds, especially after blowing your nose, coughing, or sneezing; going to the bathroom; and before eating or preparing food. If soap and water are not readily available, use an alcohol-based hand sanitizer with at least 60% alcohol.
WARNING: The FDA has recently announced that Methanol is not an acceptable ingredient for hand sanitizers and must not be used due to its toxic effects.