By Nicole Bosse
Published 2020 April 3 – From Special Issue on COVID-19
As cases of the novel coronavirus (COVID-19) surge across the world in what is now regarded as a global pandemic, governments and healthcare institutions are struggling to find ways to keep the number of infections low and contained. One common practice recommended by every expert and deemed to be effective in fighting off the virus would be the simple act of handwashing with soap and water (Center for Disease Control and Prevention 2020). How exactly does this work, and why is it so successfully in preventing the virus from infecting our bodies?
The presence of a lipid bilayer surrounding the genetic material of the SARS-CoV-2 virus is what makes it vulnerable against the use of soap. Soap contains amphiphiles, which are molecules that possess both hydrophilic and lipophilic regions, or water-loving and fat-loving properties respectively (Thordarson 2020). When mixed with water, these molecules assemble themselves in a spherical arrangement wherein the hydrophilic heads face outwards and the tails face inward. The lipid bilayer membrane of the SARS-CoV-2 virus is arranged in a similar way, and contains many important proteins that are needed by the virus to enable them to perform different
functions crucial in their process of reproduction and infection. Because the hydrophobic tails of soap molecules want to evade water when we wash our hands, they insert themselves into the lipid membranes of viruses which destabilizes the entire structure and causes the membrane to rupture. Fragments and particles of the destroyed virus are then also trapped within the structure of the soap molecules, allowing them to be washed away in water (Jabr 2020).
Disinfectant products such as those containing around 60-80% ethanol can also be used when the option to wash with soap and water is not available, although it is considered to be not as reliable as handwashing. While sanitizers and alcohol do also destabilize the lipid membranes of viruses, it is possible that we are unable to completely cover every corner of our skin, such as the areas between the fingers properly, which could allow for the continued presence of the virus (Thordarson 2020). Having wet or sweaty hands can also cause hand sanitizers to be diluted and not as effective in combating the presence of the virus. Thus, it is recommended that handwashing remain the primary way to clean ourselves because it is able to cover the entire surface of our hands and other body parts effectively (Resnick 2020).
Center for Disease Control and Prevention. 2020. Coronavirus disease 2019 (COVID-19). [cited 2020 March 19]. Available from: https://www.cdc.gov/coronavirus/2019-ncov/prepare/ prevention.html
Jabr F. 2020. Why soap works. (cited 2020 March 19). Available from: https://www.nytimes.com/2020/03/13/health/soapcoronavirus-handwashing-germs.html
Resnick B. 2020. How soap absolutely annihilates the coronavirus. (cited 2020 March 19). Available from: https://www.vox.com/scienceand-health/2020/3/11/21173187/coronaviruscovid-19-hand-washing-sanitizer-compared-soap-isdope
Thordarson P. 2020. The science of soap – here’s how it kills the coronavirus. (cited 2020 March 19]. Available from: https:// http://www.theguardian.com/commentisfree/2020/mar/12/ science-soap-kills-coronavirus-alcohol-baseddisinfectants