By now, you’ve probably learned a lot about COVID-19. But what happens to your skin in the face of viruses?
After releasing our article “How to kill SARS-CoV-2 and prevent COVID-19: finding calm in the science,” we received many questions from you about how exactly SARS-CoV-2 infects us, and particularly, what happens to our skin if met with the virus. While we don’t have experimental data specifically on SARS-CoV-2, we can share what we know about how our skin typically defends against viruses, in general.
Our skin is our largest organ, and covers most of our body, so microbes like bacteria, viruses, and microscopic fungi are constantly landing on our skin. Sometimes those microbes are pathogens (anything that causes a disease), like SARS-CoV-2. Our skin prevents pathogens from entering the body using three simple defenses: the acid mantle, antimicrobial peptides, and the stratum corneum.
THE ACID MANTLE
The acid mantle is a thin acidic film (pH ~ 4-6) on our skin, formed from sebum, sweat, and acid produced by healthy bacteria in our skin microbiome. Many viruses don’t survive well in acidic conditions like the acid mantle because they prefer the neutral pH (pH ~ 7) of our blood and the inside of our body. Soaps are usually alkaline (pH > 8 -- the opposite of acidic), so they raise the pH and temporarily destroy the acid mantle (but they also wash away germs, so we in effect trade one for the other temporarily when we wash our hands)*. Unfortunately, SARS-CoV-2 is stable at a wide range of pH, so the acid mantle likely won’t rapidly disintegrate this virus if it lands on your skin. 😞 Therefore, with SARS-CoV-2, it is that much more important to keep your skin microbiome as healthy as possible!
Pro tips:
1) You can use Wild Resilience to help support a balanced skin microbiome. With a proprietary blend of targeted phages, this serum kills bad bacteria on your skin, leaving good bacteria to flourish.
2) Using pH-balanced cleansers and soaps (pH ~ 5-7) can be less disruptive to your acid mantle and support overall skin health and wellness, especially if you regularly wash your skin. For example, atopic dermatitis, or eczema, is associated with dry, alkaline (pH > 8) skin that encourages the growth of pathogenic bacteria that can make the atopic dermatitis worse and weaken the skin defenses.
ANTIMICROBIAL PEPTIDES
Antimicrobial peptides are small biological molecules that can be produced by any cell, including bacteria, fungi, and human cells, to deactivate microbes. Two commonly used antimicrobial peptides that you may have heard about are the antibiotics polymyxin B, which you can find in Neosporin, and vancomycin, which is used in the hospital to treat infections that are resistant to other antibiotics. Both of them are made by bacteria. In the same way, bacteria and fungi in your skin microbiome can make antimicrobial peptides to help maintain your skin health by preventing pathogens from growing. This is one key reason why keeping the skin microbiome healthy and balanced is key to maintaining overall skin health. Your skin cells can also naturally produce antimicrobial peptides. For example, LL-37 is an antimicrobial peptide produced by your skin cells. People who experience eczema, psoriasis, or rosacea have too much or too little LL-37, leading to inflammation from an imbalanced skin microbiome and from pathogens that may start to grow on the skin. LL-37 is really powerful, because it can inhibit and destroy all sorts of bacteria and lots of different viruses, including some of the viruses that cause colds and the flu. No one has tested if LL-37 can inhibit SARS-CoV-2 specifically, but because LL-37 is so effective against a wide range of viruses, we would hypothesize that it is probably one way that your skin protects you against SARS-CoV-2.
THE STRATUM CORNEUM
Both the acid mantle and skin microbiome sit on a top layer of skin cells called the stratum corneum, which is 15-30 cells deep. This is the layer of skin that you actually see in the mirror. The stratum corneum is made of corneocytes, which are dead cells filled with keratin and glued together with lipids and intercellular matrix. The stratum corneum is like a wall, where the individual corneocytes are like bricks, and the lipid-filled intercellular matrix is like mortar. Together they create a water-tight barrier that stays moist. The wall is also very good at keeping out pathogens. What’s really interesting is that it’s impossible for viruses to infect the stratum corneum because viruses need to replicate in living host cells, but corneocytes can’t be infected because they are dead! In fact, even viruses that can infect the skin to cause problems like the measles rash, warts, chicken pox, and shingles always need to infect our bodies from a break in the stratum corneum (like a wound) or through our nose, mouth, or eyes. They can’t penetrate the stratum corneum from outside of our bodies by themselves. That really shows how effective the stratum corneum is at preventing viral infections, including viruses like SARS-CoV-2.
The acid mantle, antimicrobial peptides, and the stratum corneum are three effective ways that our skin keeps pathogens at bay. So if SARS-CoV-2 lands on your skin, you likely don’t have anything to worry about if your skin microbiome is healthy and you consistently wash your hands with soap and water.
However, our body has holes, both literally and figuratively, in its external defenses. Our eyes, nose, and mouth are susceptible to pathogens. Usually it’s something we breathe or ingest that gives us an infection. SARS-CoV-2 is no exception, so it is important to follow CDC guidelines, namely:
1) Please stay home as much as you can -- follow your county’s recommendations
2) When out, maintain a safe social distance of 6-13 feet from others so that you don’t breathe in aerosols from someone else’s breathing or speaking; and wear a mask to prevent the spread of aerosols from your own breathing and speaking
3) Keep up a gentle, but effective skincare routine to keep your skin microbiome balanced.
If you don’t know where to start, check out our FREE skincare PDF. You can also try Wild Resilience, which has been proven in clinical trials (99.9% confidence interval) to be effective in balancing your microbiome.
We hope that this article has shed some light on the fact that your skin really is an amazing organ that is working hard for you, which includes trying to keep SARS-CoV-2 out of your internal system. Make sure to show your skin some love and gratitude each and every day by hydrating, cleansing, and moisturizing. 💖
At Ellis Day Skin Science, we’re here to be a resource for you -- to support you in your skin health journey. If you have further questions about the impact of viruses on your skin or how viruses function, just email us at hello@ellisdayskinscience.com. We look forward to hearing from you.
About Ellis Day Skin Science
We believe that modern skincare must be revolutionized to elevate skin health. And we believe the answer is in the wild, natural world, which includes the surface of your skin.
At Ellis Day Skin Science, we pioneer natural phage-based products that target and kill bad bacteria associated with inflammation, damage, and aging, and enable good bacteria to flourish. By doing so, we aim to reset your microbiome for optimal skin health.
We use cutting-edge science to leverage nature, creating products that are just as kind and conscientious as they are effective, so that all can feel empowered with balanced, clear, radiant, and resilient skin.
Citations:
Breuer, J., and R. Whitley. "Varicella zoster virus: natural history and current therapies of varicella and herpes zoster." Herpes: the journal of the IHMF 14 (2007): 25-29.
Fluhr, Joachim W., and Peter M. Elias. "Stratum corneum pH: formation and function of the ‘acid mantle’." Exogenous Dermatology 1.4 (2002): 163-175.
Byrd, Allyson L., Yasmine Belkaid, and Julia A. Segre. "The human skin microbiome." Nature Reviews Microbiology 16.3 (2018): 143.
Izadpanah, Arash, and Richard L. Gallo. "Antimicrobial peptides." Journal of the American Academy of Dermatology 52.3 (2005): 381-390.
Chin, Alex, et al. "Stability of SARS-CoV-2 in different environmental conditions." medRxiv (2020).
Currie, Silke M., et al. "The human cathelicidin LL-37 has antiviral activity against respiratory syncytial virus." PloS one 8.8 (2013).
Barlow, Peter G., et al. "Antiviral activity and increased host defense against influenza infection elicited by the human cathelicidin LL-37." PloS one 6.10 (2011).