Hand Hygiene in Times of Coronavirus – Protecting Our First Line of Defense in the Fight against the Virus
Wearing a protective mask that covers our nose and mouth, maintaining social distancing and regularly washing our hands are protective measures that have been an integral part of our everyday lives for over half a year now. Our skin is our first line of defense against the dreaded coronavirus – and it now needs to be particularly resistant during this transitional period, which makes taking care of it more important than ever.
The number of new coronavirus infections is now rising rapidly again. Given that these infections spread through droplets, the only way we can get the virus under control is if we all actively do our bit. To avoid catching COVID-19, we need to maintain social distancing, wear face masks so as not to inadvertently spread the virus if we become infected without realizing, regularly ventilate enclosed spaces and wash our hands at every opportunity. Specific recommendations apply to hand washing in particular – we should spend at least 30 seconds on this process and clean carefully between the fingers.
Everyone unconsciously touches their face with their hands several times a day, which makes hand hygiene especially vital in the fight to stop the virus spreading. That also makes it essential to protect and look after the most important barrier protecting us from the outside world – our skin.
„We must ensure our skin doesn’t dry out despite the vigorous cleaning that is so important right now,” explains Dr. Mira Jakobs, Scientific Affairs Manager for Bepanthen at Bayer’s Leverkusen site. “If the skin loses too much moisture, it can no longer carry out its protective function to full effect. Even though we can’t become infected with coronavirus via our skin, other pathogens and harmful substances can then easily get into our bodies,” she warns.“
But how exactly does regular washing protect us against viruses? “Washing your hands thoroughly reduces the number of germs on them by up to a thousand times. That means there is less risk of pathogens getting into your mouth when you eat or into your body via the mucous membranes of the mouth, nose or eyes, for example. It also makes you less likely to pass them on to family members, friends or colleagues,” explains Marius Dörr, who is responsible for dermatological OTC products at Bayer. “And soap also plays a key role here. It’s a detergent, which means it can penetrate between fatty and water-soluble materials. Since all bacteria and many viruses are surrounded by a cell membrane, that is to say a double layer of fat molecules, soap breaks down the integrity of these pathogens and kills them,” he continues.
Our skin currently has to deal with more than frequent hand washing, though. We sanitize our hands on entering a shop or restaurant and many of us repeat the process when we head back out onto the street. After all, we have touched shopping carts, door handles and above all plastic cards and money, which may be contaminated with viruses.
A new study conducted by Australia’s national science agency CSIRO has shown that, under laboratory conditions, coronaviruses can survive for up to 28 days on smooth surfaces such as glass, stainless steel and vinyl.1,2 Examples of such surfaces include cell phone touch screens and ATMs, but also plastic banknotes like the ones in circulation in Canada. Other investigations had already demonstrated that the virus remains active for some time on plastic and stainless steel surfaces, for example.
Given that ATMs, ticket machines and self-service checkouts in supermarkets have surfaces that are touched by numerous people but may not be cleaned and disinfected regularly, these scientific findings underline the significance of hand hygiene. It is particularly important now that infection rates are rising again worldwide, even though there is currently no robust evidence suggesting the virus can be transmitted and infect people through contact with contaminated objects or surfaces. Smear infections from surfaces contaminated with viruses cannot be ruled out.3
Selecting the right sanitizer
To avoid overtaxing the skin unnecessarily, selecting the right sanitizer is crucial. “It’s important to check whether products are intended for surfaces or hands. Most products for hands also contain skincare or moisturizing substances so as not to put undue strain on the skin barrier,” says Jakobs.
Furthermore, not all sanitizers are equally effective. According to the Robert Koch Institute, products with indications such as “limited virucidal efficacy” (effective against enveloped viruses), “limited virucidal efficacy PLUS” or “virucidal” marked on the packaging are proven to work.4
Although washing and sanitizing your hands takes its toll on your skin, it is particularly vital in times of a pandemic. That makes it all the more important to maintain the skin’s protective function and not allow it to dry out. And there’s only one thing that helps here – cream, cream and more cream!
With a total surface area of 1.5 – 2 m2, the skin is the largest human organ. It accounts for approximately 8 – 12 percent of our bodyweight and has a large number of different functions.
As the organ separating our bodies from the environment, its protective function plays a particularly important role.
Our skin comprises three layers – the epidermis, the dermis and the subcutis. The epidermis is especially important for the skin’s barrier function. It is made up of a number of sub-layers. The innermost layer (basal cell layer) contains the pigment-producing cells, which are responsible for coloring the skin, and the epidermal stem cells, which continually divide and form new skin cells.
These newly formed cells make their way from the basal layer toward the skin’s surface. As they do so, a number of conversion and differentiation processes take place within them. They become flatter, adjust the metabolism and keratinize until they ultimately become incorporated into the outermost layer of the epidermis as corneocytes (horny cells), hence the term horny layer.
At the end of their development cycle, the keratinized cells become detached from the surface of the skin and are replaced by new ones, thereby continuously regenerating the epidermis.
2 See https://www.dw.com/de/studie-coronavirus-l%C3%A4nger-%C3%BCberlebensf%C3%A4hig/a-55238391 (October 15, 2020)