With drug-resistant infections on the rise, disinfecting yourself and your surroundings may seem like a good idea. However, research has clearly shown that this may exacerbate problems rather than solve them.
When it comes to preventing the spread of contagious disease, handwashing tops the list of effective strategies.1 The key is to do it, and to do it correctly, using proper products and techniques.
Studies suggest compliance with handwashing practices in healthcare settings is surprisingly low, typically no higher than 40 percent.2 An estimated 1 in 4 patients also leave the hospital with a superbug on their hands, suggesting patients also need to become more mindful about handwashing when in a health care setting.3
Unfortunately, many still labor under the mistaken assumption you need antibacterial soap to get the job done right. Many also believe using an air dryer is preferable to using a towel when in a public restroom. Surprising as it may seem, air dryers may actually spread FAR more germs than paper towels!
Moreover, as we're learning more about the human skin microbiome, researchers have noted that fewer bacteria are not necessarily better. Diverse communities of bacteria thrive on perfectly healthy skin. In fact, they're very much needed for optimal health. Hence "clean" does not mean bacteria-free.
In their paper, "Cleanliness in Context: Reconciling Hygiene With a Modern Microbial Perspective,"4 microbial ecologists at the University of Oregon argue that cleanliness isn't as simple as ridding your skin of as many microbes as possible.5
A "scorched earth" strategy may actually do more harm than good, as by removing too many beneficial bacteria you become vulnerable to more harmful ones. According to the authors:
"Most evidence suggests that the skin microbiota is likely of direct benefit to the host, and only rarely exhibits pathogenicity …
The skin is a complex immunological organ with both innate and adaptive immune cells, including multiple dendritic and T-cell subsets; antimicrobial peptides, proinflammatory cytokines, and chemokines that are secreted by keratinocytes to support an immune response …
This complex ecological context suggests that the conception of hygiene as a unilateral reduction or removal of microbes has outlived its usefulness.
As such, we suggest the explicit definition of hygiene as 'those actions and practices that reduce the spread or transmission of pathogenic microorganisms, and thus reduce the incidence of disease.'"
In their paper, the scientists examine different methods of hand drying as an aspect of this redefinition of cleanliness. As it stands, there are studies showing both pros and cons of hot air or jet drying and using paper or cloth towels.
"Utilizing a definition of hygiene that explicitly relies on reduction in disease spread rather than alterations to bulk microbial load would address concerns raised on both sides of the debate," the scientists note.
The Problem With Hot Air and Jet Dryers
Public restrooms have largely traded out paper or fabric towel dispensers for warm air dryers or jet dryers. But research suggests this may actually be counterproductive, promoting rather than preventing the spread of disease-causing bacteria.
Warm air driersblow heated air for 30 to 40 seconds per use. According to the featured paper, "most research has shown that warm air dryers may increase the number of bacteria on the hands after use." The reason for the increase in bacterial load is thought to be due to:
Bacteria inside the dryer mechanism being blown out during use
Bacteria-enriched air being recirculated
Bacteria found in the deeper layers of skin being liberated when rubbing your hands together beneath the hot air stream
Some combination of the above
Moreover, the authors note that the temperature of the air in these dryers is not hot enough to actually kill bacteria. Their purpose is solely to promote evaporation so your hands become dry.
Jet dryers are a newer alternative. These units use a high-speed jet of unheated air, drying hands in as little as 10 to 15 seconds, again by promoting the rapid evaporation of water. According to the authors:
"Many jet air dryers (e.g., the Dyson AirbladeTM) are marketed as designed with a high-efficiency particulate air (HEPA) filter built into the airflow system, which reduces the risk of redistribution of airborne microbes to the hands.
However, there is concern about the propensity of such rapid air movement to aerosolize microbes from users' hands or the surrounding environment … Particular attention has been paid to the distance such rapid air movement is capable of dispersing potentially contaminated droplets from the hands …"
In one recent study,6 jet dryers were found to spray 1,300 times more viral material into the surrounding area than paper towels, dispersing the viral load up to 10 feet away from the dryer.7,8
Paper Versus Cloth Towels
In healthcare settings, the Centers for Disease Control and Prevention (CDC) and World Health Organization (WHO) both advise using paper towels to dry your hands.
The reason for this is because the bulk of the data suggests paper towels can effectively remove surface bacteria from your hands, and effectively prevent the spread of contaminated water droplets from your hands into the environment.
As noted in a 2012 meta-analysis of a dozen studies published in the Mayo Clinic Proceedings:9
"[M]ost studies suggest that paper towels can dry hands efficiently, remove bacteria effectively, and cause less contamination of the washroom environment.
From a hygiene viewpoint, paper towels are superior to electric air dryers. Paper towels should be recommended in locations where hygiene is paramount, such as hospitals and clinics."
That said, the waste paper can be a source of bacteria, and depending on how the paper towels are manufactured and stored, the paper itself could be a source of contamination, especially if the paper towels are produced with recycled materials.
Cloth towels are the fourth and final alternative, typically used in private homes, although some public restrooms will still use a roller-type fabric towel rack. Not surprisingly, cloth towels have the highest risk of cross-contamination, although they're comparable to paper towels when you're measuring the reduction of bacteria on your hands after drying.
According to a 2014 University of Arizona study,10 towels may be the most germ-ridden item in your home. Tests revealed a staggering 89 percent of kitchen towels and nearly 26 percent of bathroom towels were contaminated with coliform bacteria — microbes associated with food poisoning and diarrhea.
The primary reason for this is the moisture cloth towels retain, which serves as a perfect breeding ground for bacteria. To properly cleanse towels of potentially harmful bacteria, be sure to wash them in HOT water, as most of these organisms live at body temperature.
While the issue of hand drying is important, it should not overshadow the issue of actually washing your hands in the first place. As noted by The Verge:11
"All this discussion of drying, though, ignores one obvious, overwhelmingly important fact: [I]t's washing your hands that's key when it comes to personal hygiene, and people just don't wash their hands enough.
When you look at advice and research from agencies tasked with public health like the CDC and WHO, there's scant mention of drying techniques because getting people to wash is tricky enough. In a U.K. study,12 99 percent of people visiting a public bathroom said they had washed their hands after going to the toilet. Recording devices showed that only 32 percent of men and 64 percent of women actually had."
Anytime you visit a health care facility. Before leaving the premises, be sure to wash your hands
Before and after food preparation, especially if you're cooking poultry, raw eggs, meat or seafood. It's also advisable to wash your hands directly before sitting down to eat
After you've used the restroom, and after each diaper change
Before and after caring for someone who is ill, and/or treating a cut or wound
How to Properly Wash Your Hands
Hand washing is a simple and effective way to reduce your exposure to potentially disease-causing germs and reduce your chances of getting sick and/or spreading disease to others. Unfortunately, research14 suggests as little as 5 percent of people wash their hands in a way that will actually kill infection and illness-causing germs. To be truly effective for disease control, be sure to follow the following handwashing guidelines:
1.Use warm, running water and a mild soap. You do NOT need antibacterial soap, and this has been scientifically verified. Even the U.S. Food and Drug Administration (FDA) has stated15 "there is currently no evidence that [antibacterial soaps] are any more effective at preventing illness than washing with plain soap and water."
It's even been found to aggravate the growth of liver and kidney tumors.18 In pregnant women, triclosan has been shown to affect hormone regulation, and may interfere with fetal development.19,20,21,22
Alcohol-based products are also best avoided. While they've been shown to significantly reduce bacterial diversity on your hands, this decreased bacterial diversity may actually increase your likelihood of carrying potential pathogens on your hands by eliminating naturally-occurring protective species.23
2.Work up a good lather, all the way up to your wrists, scrubbing for at least 15 or 20 seconds (most people only wash for about six seconds).
3.Make sure you cover all surfaces, including the backs of your hands, wrists, between your fingers and around and below your fingernails. See suggested techniques in the video above.
4.Rinse thoroughly under running water.
5.Thoroughly dry your hands, ideally using a paper towel. In public places, also use a paper towel to open the door as a protection from germs that the handles may harbor.
As noted at the beginning of this article, your skin is actually an important primary barrier against germs, so obsessive-compulsive washing, especially in dry environments, can actually increase your risk of getting sick by drying out your skin, allowing potentially harmful bacteria entrance into your body. So, maintain a balance — wash when advisable (see above) but avoid washing your hands to the point of irritating your skin.