The practice of handwashing
Handwashing is a simple, but very effective measure against disease and pathogen spreading. By keeping handwashing as a habit, we might significantly reduce the risk of getting sick or infecting others. Studies have also shown that the best way to clean your hands is simply with soap and clean, running water. The soap/detergent compromises the cell membrane, which is mostly composed of lipids (Mcdonnell and Russell, 1999). The soap also helps to dissolve dirt and loosen hydrophobic material from the surface of your hands and thus can be removed by the running water. Handwashing with only water has been found to reduce the presence of bacteria to 23%, while additional soap reduced the presence of bacteria to 0.2-8% (Burton et al., 2011; Jensen et al., 2017). This decrease is comparably low if we consider the average number of microbial cells on human hands, which is around 1 billion per cm2 (McGinley et al., 1988). A 1% reduction still results in 10-100 million cells. This number might encourage you to use soaps or other sanitizing products that contain antibacterial agents such as iodine (traditionally for wound disinfection), triclosan (common in liquid soaps), and triclocarban (common in bar soaps).
It is probably hard to believe, but actually, most of the manufacturers of these products did not provide the necessary and adequate data to establish the safety and effectiveness of their antibacterial soaps for public use. Available studies to date show that antimicrobial soap is only more effective when heavily-soiled hands and mostly did not reduce the risk for viral infections (Larson et al., 2004; Perez-Garza et al., 2017). Moreover, the long-term exposure to the active ingredients in these products might even pose health risks. In the case of triclosan in the USA, it is so widely used in various consumer goods and personal care products, that 75% of the US population was estimated to be exposed to this compound on a regular basis. Due to the absorption, accumulation, and transformation, triclosan has been suggested to pose health risks, such as bacterial resistance or hormonal effects (Weatherly and Gosse, 2017). Consequently, FDA issued a rule establishing that over-the-counter consumer antiseptic wash containing 19 specific active ingredients can no longer be marketed until proven safe for long-term daily use and more effective than plain soap and water in preventing illness and the spread of certain infections (FDA, 2016).
What’s more important is to practice a proper handwashing technique (Figure 1). Out of key variables such as soap concentration and volume, lather time, water temperature, and active ingredients, lathering time (20 s) significantly influenced handwashing efficacy (Jensen et al., 2017). Fingertips and the areas beneath fingernails especially require extra attention since it harbors the most microorganism and is most difficult to clean (McGinley et al., 1988; Lin et al., 2003). Although it is recommended to wash your hands for 15-30 s, it is not a magic number, and it is also essential to use your common sense. If your hands are extra dirty or if you will cook for other people, you might want to wash slightly longer. Whether you sanitize your hands with soap or other sanitizing products, you should also be cautious. Excessive usage might cause side effects, e.g., dermatitis due to dysbiosis of skin microbiota marked by the rise of Staphylococcus aureus (Murillo and Raoult, 2013; Beiu et al., 2020). You should clean your hands particularly after being in public areas, before meals, after coughing/sneezing, after using the toilet, and when you think your hands are actually dirty. Whatever drying methods you use, it is good to ensure low residual moisture to minimize touch-contact-associated bacterial transfer following handwashing (Patrick et al., 1997; Gustafson et al., 2000). While handshaking is not encouraged during this pandemic situation, no shake-hands while your hands are wet, even after this situation is over.
Next to this, hand-sanitizing gels or wipes with ethanol 60-70% are commonly marketed. However, these are not equivalent substitutes and should be treated only as an alternative, better-than-nothing option when soap and running water are limited or not available rather than mere convenience. Studies have shown the limited spectrum of activity of alcohol-based sanitizing products, e.g., against Gram-negative bacteria, but not against bacterial spores, or nonenveloped viruses such as the enteric viruses (Todd et al., 2010; De Aceituno et al., 2015; Foddai et al., 2016).
How to wear mask properly (CDC, 2020a)
Cloth face coverings are an additional step to help slow the spread of airborne pathogens (Leung et al., 2020), e.g., COVID-19 when combined with everyday preventive actions and social distancing in public settings. The idea is to wear the face-covering to help to protect others in case you’re infected but don’t have symptoms, and others will do the same to protect you. Therefore, you should keep the covering on your face the entire time you’re in public.
Who should NOT use cloth face coverings: children under age 2, or anyone who has trouble breathing, is unconscious, incapacitated or otherwise unable to remove the mask without assistance.
Cloth face coverings are NOT surgical masks or N-95 respirators. Surgical masks and N-95 respirators must be reserved for healthcare workers and other medical first responders, as recommended in CDC guidance.
Wear your Face Covering Correctly
Wash your hands before putting on your face covering
Put it over your nose and mouth and secure it under your chin
Try to fit it snugly against the sides of your face
Make sure you can breathe easily
Don’t put the covering around your neck or up on your forehead
Don't touch the face covering, and, if you do, wash your hands
Take Off Your Cloth Face Covering Carefully, When You’re Home
Untie the strings behind your head or stretch the ear loops
Handle only by the ear loops or ties
Fold outside corners together
Place covering in the washing machine (learn more about how to wash cloth face coverings)
Be careful not to touch your eyes, nose, and mouth when removing and wash hands immediately after removing.
Cloth face coverings should be washed after each use. It is important to always remove face coverings correctly and wash your hands after handling or touching a used face covering.
How to clean your mask/ face covering correctly (CDC, 2020b)
Washing machine
You can include your face covering with your regular laundry.
Use regular laundry detergent and the warmest appropriate water setting for the cloth used to make a face covering.
Washing by hand
Prepare a bleach solution by mixing 20 ml bleach per 1L water.
Check the label to see if your bleach is intended for disinfection (hypochlorite). Some bleach products, such as those designed for safe use on colored clothing, may not be suitable for disinfection. Ensure the bleach product is not past its expiration date. Never mix household bleach with ammonia or any other cleanser.
Soak the face-covering in the bleach solution for 5 minutes.
Rinse thoroughly with cool or room temperature water.
How to dry the mask
After washing, make sure to dry cloth face-covering after washing thoroughly. With a dryer, use the highest heat setting and leave in the dryer until completely dry. With air dry, lay the mask flat and allow it to dry completely. If possible, place the cloth face-covering in direct sunlight.
After all, wearing a mask is not enough to protect us from COVID-19. Following basic hygiene practices and keeping social distancing is necessary.
Stay at least 1.8 m away from others
Avoid contact with people who are sick
Wash your hands often, with soap and water, for at least 20 seconds each time
Use hand sanitizer if soap and water are not available
S.A.D Team
References
Beiu, C., Mihai, M., Popa, L., Cima, L., and Popescu, M. N. (2020). Frequent Hand Washing for COVID-19 Prevention Can Cause Hand Dermatitis: Management Tips. Cureus 12. doi:10.7759/cureus.7506.
Burton, M., Cobb, E., Donachie, P., Judah, G., Curtis, V., and Schmidt, W. P. (2011). The effect of handwashing with water or soap on bacterial contamination of hands. Int. J. Environ. Res. Public Health 8, 97–104. doi:10.3390/ijerph8010097.
CDC (2020a). How to Safely Wear and Take Off a Cloth Face Covering | CDC. Available at: https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/how-to-wear-cloth-face-coverings.html [Accessed June 28, 2020].
CDC (2020b). How to Wash a Cloth Face Covering | CDC. Available at: https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/how-to-wash-cloth-face-coverings.html [Accessed June 28, 2020].
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