How does not washing your hands make you a healthier person?
Category: Health Published: May 3, 2013
By: Christopher S. Baird, author of The Top 50 Science Questions with Surprising Answers and Associate Professor of Physics at West Texas A&M University
Avoiding hand washing will make you ill, not healthy. There seems to be a trendy viewpoint recently that having bad hygiene will make you healthier in the long run because it will boost your immune system by exposing you to more germs. This view is false, although it can be traced back to a true principle. The life-saving application of vaccines operates on the principle that if you expose your immune system to a certain germ, it will learn to recognize and build up an immunity against that germ that lasts for years. The trendy viewpoint therefore arose that having bad hygiene is like giving yourself mini-vaccines and will boost your immune system, making you healthier in the long run. This extrapolation from vaccines to bad hygiene is wrong for several reasons:
1. A specific vaccine only makes you immune to a specific disease, it does not boost your entire immune system in general. Vaccinating a child against measles will not make him immune to polio. That is why a child must receive so many different vaccines, that is, to protect him against all the major infectious diseases. Getting sick from a germ on your unwashed hands will only boost your immunity against that specific germ. But there are thousands (perhaps millions) of different types of infectious germs. The common cold alone can be caused by over 200 different viruses. To become immune to the common cold, you would have to get sick 200 times with each different strain of the virus. Even after doing that, you would still not protected for the reason mentioned next.
2. Germs evolve. When your body becomes immune to a certain germ, it is only developing immunity to the version that has infected you. Later versions of the same germ may have evolved into a different enough organism that your immune system is not able to recognize it. This is why the influenza vaccine must be reformulated every year. The influenza vaccine is updated annually to protect against the most current strains of the virus (or at least the most common current strains; it can't protect against all strains as the virus is constantly evolving into new strains). Getting sick from the a germ on your unwashed hands may make you immune to that particular strain, but will not make you immune to later versions that have evolved.
3. Vaccines consist of germs that have been altered to provoke the desired immune boost without giving you the disease. Germs on your unwashed hands have not been. To create a vaccine, scientists take a germ and either kill it, deactivate its toxicity, weaken it, or make a non-toxic copy. When the altered germ is injected into a patient, its molecular shape is learned and remembered through the production of antigen-specific antibodies. But because the germ has been rendered non-toxic, the patient reaps the benefits of immunity without actually getting the disease. In contrast, the germs on your unwashed hands are fully active and able to cause disease. You may develop immunity to a particular hand-borne pathogen, but you may also die or sustain long-term impairment in the process.
Hand washing has been one of the greatest advances in medicine. Before the concept of germs was developed, Dr. Ignaz Semmelweis made an interesting discovery. As described in the biography written by Sir William Japp Sinclair, Dr. Semmelweis was working in the Vienna General Hospital in the 1840's when he found a discrepancy in mortality rates between the two different child-birthing clinics of the hospital. On average, about 10% of the birthing mothers in the First Clinic died of childbed fever, while less than 4% of the mothers died of childbed fever in the Second Clinic. Year after year, the mortality rate was consistently higher in the First Clinic. Word got out and laboring mothers begged to be admitted to the Second Clinic and not the First Clinic. Upon examination, Dr. Semmelweis discovered that the only difference between the two clinics was that the physicians in the First Clinic also performed autopsies, whereas those in the Second Clinic mostly did not. He reasoned that the deadly disease was being carried from the corpses to the birthing mothers on the hands of the physicians. Upon instituting a strict chlorine hand-washing policy in mid-1847, the fever death rate in the First Clinic dropped from 18% in April to 1% in July. In the following year, the death rate dropped to zero. Tragically, Dr. Semmelweis' discovery was ignored and ridiculed by the medical establishment of his time.
The CDC states "Keeping hands clean through improved hand hygiene is one of the most important steps we can take to avoid getting sick and spreading germs to others. Many diseases and conditions are spread by not washing hands with soap and clean, running water." To stay healthy, you should wash your hands when preparing food, eating food, caring for an invalid, using the toilet, treating a wound, changing diapers, coughing or sneezing into your hands, and after touching garbage. Because of the immense impact of hand washing on health, many states and countries have laws requiring employees to wash hands before handling food and after using the toilet. The CDC estimates that about 500,000 children die each year as a result of not washing their hands. While we have focused on hand-washing in particular, these concepts apply broadly to all hygiene. Being lazy towards germs will make you less healthy in the long run, not more.