There are many ways to avoid infection, but few might be as simultaneously simple and effective as handwashing.
According to the Centers for Disease Control and Prevention, keeping hands clean is one of the most important steps a person can take to avoid getting sick and spreading germs to others. While skeptics might question just how big an impact handwashing can have, the science behind washing hands paints a pretty strong picture of just how beneficial this particular component of personal hygiene can be.

How germs get you sick
The CDC notes that feces from people and animals are considerable sources of germs, including salmonella and E. coli. These germs can get onto people’s hands after they use the toilet or change a diaper. People who handle raw meats also be exposed to such germs, as these foods can contain invisible amounts of animal feces on them. The amount of germs contained in small amounts of feces may come as a shock. Research published in the journal Applied and Environmental Microbiology found that a single gram of human feces weighing about as much as a paper clip can contain one trillion germs. 

What does handwashing do?
With so many germs floating around, it may seem as though something as simple as handwashing couldn’t be nearly as effective as it’s said to be. But the CDC notes that handwashing removes germs from hands, thereby removing an easy way for germs to enter the body and be passed on to others. For instance, many people habitually touch their eyes, nose and mouth without thinking twice, and doing so provides an easy way for germs to enter the body via the hands. By washing their hands, people can cut off this easy entryway for germs. 
Handwashing also presents germs from entering the body while eating. Germs from unwashed hands can get into people’s food and drinks, and can even multiply in some foods and beverages, potentially contributing to illness. 
Washing hands also prevents the spread of germs by preventing them from being transferred from hands to handrails, table tops or toys, where they can then spread to other people’s hands.
Handwashing is a simple yet effective way to stop the spread of germs. And it just might be the simplest way to avoid illnesses.