*Nothing in this article is intended as medical advice. Seek guidance from a physician if you have any questions.*
Time and time again, data has demonstrated that Americans are not very good at sanitizing their hands. Survey data from January 2020 indicates that less than half of Americans wash their hands after going to the bathroom. Worse, studies have shown that doctors wash their hands just over half of the time between patients.
These signs do not bode well. In our collective moment, handwashing and sanitation are of the utmost importance as Covid-19 may possibly be the worst disease outbreak in modern history. As the United States Centers for Disease Control states, “Handwashing is one of the best ways to protect yourself and your family from getting sick.” Today, we’ll take a deep dive into a couple different forms of hand sanitation, how to use them, and discuss their relative advantages.
Why Sanitize at All?
Before beginning a discussion on the exact means of hand sanitation, we should first explore why it is important at all. Simply put, people spread disease. During most epidemics, human beings are one of the primary ways that contagious diseases are able to propagate. This was true of the second measles outbreak in the 1980’s, the polio outbreak in the early to mid 20th century, the diphtheria epidemic in the 1920’s, and the Spanish flu of 1918. These diseases all have one thing in common: they are pathogenic. Pathogenic diseases are those that are caused by pathogens, or disease-causing microorganisms. In the vast majority of instances the pathogen is either a virus (measles, chickenpox, flu, herpes, HIV, Covid-19) or a bacterium (cholera, leprosy, tuberculosis, syphilis.)
Depending on a large number of variables including type of pathogen, climate, and cleaning procedures, pathogens can live on a variety of different surfaces for months. In the case of Covid-19, the length of time that the virus can survive outside of a host (i.e. you and me) is still up for debate. Estimates in late March 2020 produced figures around 72 hours, which is consistent with existing data on other coronaviruses, the family that Covid-19 belongs to.
Considering that humans tend to manipulate almost every object in their environment with their hands, sanitizing that part of the body can be an effective means of damping disease transmission. Say for example you are shopping at a grocery store. If you pick up 15 items but only purchase 10 of them, your germs are left on the 5 items left in the store. Multiply these numbers by hundreds of shoppers and suddenly public spaces becomes magnets for germs. Clean hands can be a fantastic way to make sure those germs don’t make their way into your body, or the body of anyone around you.
The first, and probably most obvious means of sanitation is handwashing. The CDC lists many different instances in which you should wash your hands. These include when interacting with food (preparing, eating, cleaning), when in contact with diseased or injured individuals (treating a wound, caring for the sick), interacting with pets, and touching anything obviously dirty (blowing your nose, taking out the trash, etc.) In light of the current pandemic, the CDC also now recommends washing your hands before and after entering or exiting a new building, especially before entering a residence.
Handwashing does not kill bacteria, and that is not the point. Handwashing is meant to be an effective way of removing bacteria from your hands. The soap acts as something called a nonpolar solvent, meaning that it is very good at removing dirt and oils - both places that pathogens love to hide (some soaps also include antibacterial agents, but those do nothing against viruses.) The data shows that this is very effective. Studies indicate that handwashing for just 15 seconds reduces overall bacterial counts by 90% and an extra 15 seconds brings that number to over 99%.
- Wet your hands with running water, turn the tap off, apply soap.
- Lather your hands with soap. This step is meant to make sure that the soap molecules touch every nook and cranny on your hands.
- Scrub both of your hands for at least 20 seconds. As you may have heard before, this is, conveniently, roughly the amount of time to sing the song “Happy Birthday” twice.
- Turn the tap back on, wash all soap off your hands.
- Dry your hands on a clean towel or let them air dry.
In recent weeks, article after article has been written about the national and world-wide shortages of hand sanitizer. The shortage is so acute in some places that breweries and distilleries have stepped up and began manufacturing hand sanitizer in place of beer and spirits. There is a good reason that people are flocking to store to purchase bottles as soon as they’re in stock: it is an effective means of killing pathogens.
Hand sanitizer is effective for a different reason that soap. While soap aims to remove bacteria and virions from the hands, hand sanitizer aims to kill. For bacteria and viruses, the alcohol in the hand sanitizer effectively disrupts the structure of the membrane (for bacteria) or the viral capsule (for viruses), effectively killing them. The most effective hand sanitizers contain between 60% and 70% ethyl alcohol. This concentration is even more effective than 100% alcohol. This is because the small amount of water in the solution helps the alcohol to penetrate to the bacteria and virions.
So, how exactly is the use of hand sanitizer different from hand washing? The CDC lists several steps to effective hand sanitation:
- Hand sanitizer works most effectively when hands are clean and unsoiled. Organic matter (dirt, oil, grime, etc) “protects” the pathogens from the effects of the hand sanitizer. So, if your hands are dirty, make sure you wash them soon for maximal effect.
- Apply hand sanitizer to the palm of one hand.
- Rub vigorously, like when hand washing, to make sure the solution comes into contact with all parts of your hand.
- Unlike soaps, hand sanitizer can dry your hands out. It can be a good idea to apply hand moisturizer occasionally to prevent drying.
Article by: Patrick O'Hare