Key Learning Objectives
Discover what “flattening the curve” means and why it’s important.
Understand how washing hands frequently helps reduce risk of viral infections.
Find out why washing with soap and water is the first choice by public
health authorities and use of hand sanitizers is plan B.
Learn the recommended hand washing technique to prevent viral infections.
What’s Flattening the Curve Mean? Why Are Your Prevention Actions Important?
A key part of managing the COVID-19 pandemic is preventing the infection of as many new people as possible. This is especially important right now, because the growth in the rate of new infections, if left unchecked, could exceed the medical system’s capacity to treat them.
One of the public health goals of prevention is “flattening the epidemic curve*,” which essentially means decreasing the growth of new infections now, so they can be spread out over time. This is the reason why businesses are asking employees to work from home and governments are enacting policies to support social distancing strategies. In essence, public health wants to push some of the infections that might otherwise occur in the next weeks to sometime in the future … the further into the future the better.
*To find out more about what flattening the curve means, we recommend reading National Public Radio’s Flattening A Pandemic's Curve: Why Staying Home Now Can Save Lives.
If there were something you could buy and use that would lower your odds of getting the types of viral infections that cause respiratory infections, would you buy and use it? The good news is that there is something … it’s soap.
This spreading out of infections over time helps for a few reasons. It decreases the risk of medical services being overwhelmed right now. It gives time to adjust to better deal with the problem. It helps health care clinics and hospitals use available resources for the people most in need. It buys time to manufacture and deliver more of the items they’ll need for treatment. And, it means that more of the cases will occur some time in the future when better treatments are available.
The goal of flattening the curve isn’t to stop all infections; it’s to decrease new infections now, because the next few weeks are when the healthcare system is at the most risk of being unable to keep pace. Social distancing is one way to flatten the curve. But anything each of us can do to prevent ourselves and others from getting sick now, will help the medical system care for people most in need. With that in mind, we want to give you more information on why and how, by following better handwashing techniques, you can contribute to flattening the curve.
Interrupting Viral Spread From Surfaces to Mucosal Membranes
One way that viruses, like the SARS-CoV-2 virus causing COVID-19, and those that cause the common cold and flu, spread is through respiratory droplets produced when an infected person coughs or sneezes. The virus in these droplets ends up on nearby surfaces (or on other people nearby).
How long a virus will survive on a surface depends on the type of virus and the kind of surface. Scientists will know much more about the virus causing COVID-19 in the future, including how it is transmitted. But preliminary research published as a letter to the editor in the New England Journal of Medicine on March 17, 2020 suggests the SARS-CoV-2 can survive on surfaces; surviving for longer on steel and plastic surfaces (up to 2-3 days) compared to copper or cardboard (less than 1 day).
When we touch a surface with a virus on it, it’s possible the virus will stick to our skin. Once a virus is on our hands, it can get transferred to the eyes, nostrils or mouth (i.e., mucosal areas). These areas give viruses a much more direct way to get into the respiratory areas where they can multiply and cause the symptoms of colds and flu.
Washing hands frequently is one of the most important prevention steps you can take to protect yourself and others near you against colds and flu. Along with social distancing, it’s a primary emphasis of the public health recommendations for preventing COVID-19 infection.
Okay. All we need to do to interrupt viral transmission is stop touching our face. Sounds easy in theory, but in practice this is really hard. One of the takeaways from research is that most people are constantly touching these areas of the face (but are not aware of it). In a small study of medical students, on average they touched their faces 23 times … per hour! A bit under half of these touches were to the mouth, nose, or eyes. In another study that only measured touches to the mouth, nose, and eyes, the average was almost 16 per hour.
Since stopping subconscious behaviors like face touching is difficult, we need a strategy that we can act on. This is where hand washing with soap and water enters the picture. It is a way to prevent the possible spread of viruses from surfaces, to hands, to the mucosal areas of the face.
What’s the Evidence for Handwashing?
We want to share two pieces of evidence on why frequent hand washing is important for prevention. The first is from what has been dubbed “Operation Stop Cough.”
In 2001, Scientific American published an article called Navy Recruits Wash Their Hands of Coughs and Colds. The background was that the military had found out that many new recruits developed some form of cough or flu-like illness in the first few months of their training. Since new recruits live in dormitories, once one was infected, there was increased risk the illness would spread among other recruits living and working in close proximity.
In 1996 a Navy base in Illinois started “Operation Stop Cough” in an effort to see if encouraging certain behaviors could reduce colds and flu. According to Scientific American: "As part of the program, commanding officers instructed recruits to wash their hands at least five times a day. To facilitate this task, the navy installed liquid-soap dispensers at all sinks and allowed wet sinks to pass inspection. In addition, drill instructors received monthly education from preventive medicine personnel on the importance of handwashing."
The results of this program were published in the American Journal of Preventive Medicine in the August 2001 issue in an article titled Handwashing and respiratory illness among young adults in military training. One reported result was: "A 45% reduction in total outpatient visits for respiratory illness was observed after implementation of the handwashing program." So, from a public health perspective, all of the recruits benefited from the program (i.e., the program itself flattened the curve).
Another interesting, and not unexpected finding was that “...frequent handwashers self-reported fewer respiratory illness episodes when compared to infrequent handwashers.” While the program improved the results of all the recruits, the individuals who washed their hands the most, benefited the most.
The last finding was that adhering to the handwashing program was challenging for many of the recruits, especially in the time-constrained setting of military training. This should also not be unexpected. Turning new behaviors into habits takes effort AND time; it requires focus and work.
If we want to shift the viral prevention odds in our favor, washing hands 5+ times a day is one way to do it. Scientific evidence suggests that hygienic measures, such as handwashing, are one of the most effective ways to prevent upper respiratory tract infections. This is especially true around younger children.
The second study is of a web-based educational program called PRIMIT (PRImary care trial of a website based Infection control intervention to Modify Influenza-like illness and respiratory infection Transmission). The results of PRIMIT were published in the Lancet in 2015. A brief summary of the study and results was in Science Daily. We’ll summarize the key points.
PRIMIT used a website to educate more than 16,000 United Kingdom households on the importance of washing hands frequently as a way to prevent the spread of colds and flu. This study took place during cold and flu seasons from January 2011 to March 2013. Participants took part in 4 web-based sessions, with each session delivered at one week intervals (i.e., they had to wait one-week between each session of the course).
Taking the PRIMIT course (1) reduced the risk of catching and passing on respiratory tract infections to other household members, and (2) resulted in about 10-15% fewer doctor visits and antibiotic prescriptions. Only about half (51%) the individuals in the PRIMIT group reported at least one respiratory infection compared with close to 6 out of 10 (59%) in the group that did not take the online course. The risk of catching a flu-like illness was about 20% lower in the PRIMIT group. So, the education didn’t prevent all infections, but did significantly flatten the curve.
Why Does Washing Hands Reduce Viral Infections?
The Centers for Disease Control and Prevention (CDC) officially recommends washing your hands with soap and water thoroughly for at least 20 seconds, especially after going to the toilet or when hands are visibly dirty, before eating and after blowing one's nose, coughing, or sneezing. They also recommend to use hand sanitizers only as a backup, when you can’t use soap.
We’ve shared two studies that have reported reductions in colds and flu. But why does handwashing work? And why is the first choice soap and water, and not hand sanitizers?
The short story is that good old fashioned soap kills many types of viruses, including coronaviruses. But there’s a caveat to this: It kills viruses only if they are exposed to the soap for a sufficient amount of time. Long enough turns out to be about 20 seconds. During these 20 seconds, the soap will be putting increasing stress on the fatty membranes of the virus, eventually pulling it apart, killing the virus.
Washing with soap and water for 20 seconds is a better strategy for reducing cold and flu viruses on hands than using hand sanitizers.
The other thing soap does, and this is one of the reasons it’s used to wash dishes and clothes, is it sticks to fatty substances (like the grease on a plate) and allows them to be rinsed away with water. Some degree of the protection against viruses is believed to occur because of this “sticking to and washing away effect.” The outer membranes of coronaviruses and the cold and flu viruses are made of fatty substances. Trying to wash the virus off with water alone is unlikely to work. The glue-like interaction between the virus and skin is too strong. But when soap is added, like with the grease and dirt from our dishes and clothes, water can wash away viruses.
For a more detailed explanation, we recommended investing about 5 minutes to watch a Youtube Video called “The Tiny Compound That Makes Soap A Coronavirus Killer.”
We also encourage you to watch an AsapSCIENCE Youtube video from about the 55 second mark till 1 minute 35 seconds. During that 40 second segment, the AsapScience team discusses an experiment that compared washing with soap and water for 40 seconds … verse a few types of hand sanitizers … verse doing nothing. They measured the amount of influenza A virus found on the hands of hospital workers. Doing nothing was not a good strategy. Hand sanitizers worked. But the best results on eliminating the virus from hands occurred with washing with soap and water for 40 seconds.
What Should I Do? How Should I Do It?
Advice to wash your hands frequently is a vague goal (i.e. it’s not measurable). One of the keys to transitioning new behaviors into habits is to make the behavior something measurable. In general, disease prevention experts recommend that we wash our hands 5-6 times a day. “Operation Stop Cough” also selected 5 times a day as its criteria. So a useful first step, at least from a biohacking perspective, is to decide how many times a day you’ll wash your hands, and then track it. We recommend choosing a number of 5 or higher.
From a habit perspective, it’s best to anchor at least some of these 5+ times of hand washing to other actions or habits you already take. Possible options are events like after using a doorknob to enter a room or before every time you eat or drink.
It’s easiest to create new habits when we anchor them to existing habits. Find things you are already doing and add washing your hands to those activities every time you do them.
We’ve already mentioned that to get more antiviral benefits from washing with soap and water, it’s important to wash your hands for at least 20 seconds. It’s also important to wash them in the right way. Watch this 90-second YouTube video tutorial on proper handwashing technique created by the World Health Organization. The 5 key steps to remember are:
Wet your hands with clean, running water (warm or cold), turn off the tap, and apply soap.
Lather your hands by rubbing them together with the soap. Lather the backs of your hands, between your fingers, and under your nails.
Scrub your hands for at least 20 seconds.
Rinse your hands well under clean, running water.
Dry your hands using a clean towel or air dry them.
We mentioned the PRIMIT study when we talked about some of the scientific evidence of hand washing. You can access the same course and lessons online at https://www.lifeguideonline.org/player/play/primitdemo. It takes about 15 minutes of time to go through the information.
The brain doesn’t tend to put much effort into remembering—never mind acting—on things it only encounters once. This changes if it can be convinced they are important. Repetition is one of the best methods for doing this convincing. In other words, you’re likely to get more benefits from reviewing this brief 15-minute course a few times over the next couple of weeks as opposed to just once. If you have teenagers, or other people in your household, it can be something you share with them.
We recommend printing a copy of page 8 from the PRIMIT course (When Could You Wash Your Hands More?) and putting it somewhere you'll see it. This will serve as a reminder of the times it's most important to wash your hands. This page also serves as a commitment reminder, since you’ll be selecting the frequency you plan on washing your hands more for each item.
If you have younger children, Henry the Hand Champion Handwasher School Visit Video might be a useful resource.
More from Henry the Hand can be found at www.henrythehand.com.
For many of us (this author included) washing hands frequently, and in the correct way, is not a habit. James Clear (author of Atomic Habits) is an expert on new habits. If you want strategies to help you or others you care about in building healthy habits, visit his website to view The Habits Guide: How to Build Good Habits and Break Bad Ones or listen to him interviewed by Dave Asprey on Bulletproof Radio.
The last thing we want to mention has to do with time and energy. These are finite resources: Using them for one thing means less is available for others. One option for interrupting viral transmission from surfaces to our face is to sanitize everything we might touch … before touching them. But like with facial touching, much of our touching is subconscious. And this strategy can take a lot of time and effort, which might be better purposed for some other activities.
One of the fundamental premises of the biohacking movement is to pursue strategies that give us more return for less investment of time, energy, or money. Washing hands fits into this spirit of biohacking. This does not mean you shouldn’t sanitize things. But it does mean that If you’re only able to commit to one hygiene action, washing hands frequently should be it.