A little dirt never hurt, right?

The dirty percentages of truth behind our hand washing practices.

By now you’ve probably read, or at least glanced at, several articles or posters about why hand washing is important. These sources have probably stressed that proper hand washing decreases the spread of diseases like influenza and foodborne illnesses, but if you’ve had this year’s flu you may have decided that all the due-diligence of hand washing is just hogwash. Or maybe you believe that “a little dirt never hurt” and that exposing yourself to a few germs will actually build your immune system. So, is all our hand washing actually working, and is it worth doing?

First of all, let’s look at how much hand washing we are actually doing. A 2013 study done by Michigan State University (MSU) showed that approximately 67 percent of people living in and around the MSU area washed their hands with soap and water after using a public bathroom (participants were 40 percent males and 60 percent females). Unfortunately the majority of those people washed for only five to 14 seconds, while it is recommended that hands be washed with soap and warm water for 20 seconds. Only five percent of those studied washed for greater than 15 seconds, and a whopping 10 percent of people did not wash at all. Other studies in 2008 and 2006, respectively, showed that college-aged males washed their hands only 43 percent of the time after urinating and 78 percent of the time after having a bowel movement (69 percent and 84 percent for women), and that restaurant food handlers washed hands only 32 percent of the time after doing an activity which required it. Astounding numbers in my book, but what does it all mean?

It means we’re all ingesting quite a few germs, our own and others, on a daily basis. While not all germs make us sick, many do, and some even cause death. Both the National Institute of Health (NIH) and Center for Disease Control (CDC) have studied the effects of hand hygiene on reducing the spread of disease. They show that proper hand washing (with regular soap and warm water) can reduce the incidence of gastrointestinal illness (such as Norovirus, Salmonella and other diarrheal diseases) by 31 percent and respiratory illness (like influenza and colds) by 21 percent. In people with weaker immune systems (very young, elderly, HIV positive, cancer, etc.) the incidence of diarrheal disease can be diminished by 58 percent with proper hygiene. In other words, when it comes to diarrheal illnesses that are easily transmitted from hands to other people, food, utensils, toys, etc. the best defense is good hand washing. These are illnesses for which there is no way to “build immunity” and you are likely to get sick from them whenever you have been exposed to enough germ cells, which is why your kids may contract several “stomach bugs” each season.

In the case of respiratory illness like colds and influenza there is some evidence that exposure to germs at a young age will boost immunity when you’re older. However, there are hundreds of different flu strains and you only gain immunity to one or two a year if you get sick. Given that the flu mutates rapidly, the chances of you having immunity to the next strain is pretty slim, however when you get to the elderly stages of life you might find that you are sick less often.

Now let’s do a little math problem to bring it all together. Let’s say you and/or your family contracted the ghastly Norovirus three separate times this winter and missed a total of three days of work (or your kids have missed three days of school) because of it. With proper hand washing 100 percent of the time, you can decrease those missed days by at least one! Add to that the number of people who have not contracted the illness thanks to your proper hygiene. Michigan State University Extension recommends staying home when sick, and properly washing hands with soap and warm water for 20 seconds. Hands should always be washed after using the bathroom, before preparing and serving food, after cooking with raw meats and eggs, and after blowing the nose, being around those that are sick, or cleaning up after a sick person.

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