Coronavirus; viability on surfaces
The coronavirus survives on different surfaces for different amounts of time. Wash your hands. Soap has a biochemical structure that makes it the enemy of the coronavirus.
If you are nervous about touching things that may have been contaminated with the coronavirus, you aren’t alone. I, for one, now dread going to the mailbox in case of contamination either on my mailbox door or on the content inside the mailbox. Although the risk is probably low, it does represent a small possibility because the coronavirus can live outside the human body for a small period of time. Each virus survives on different surfaces for different amounts of time. We are just learning about the survivability of the coronavirus in various environments outside of the body.
Coronavirus survival time in various environments
On March 17 2020, the New England Journal of Medicine published the details of a study that tested the survival time (viability) of the coronavirus (SARS-CoV-2) compared to the SARS virus (SARS-CoV-1) on various surfaces and environments from everyday life. The National Institute of Health (NIH) endorsed the study that very same day, so the data should be considered as solid evidence until further studies show us differently.
The findings showed that the survival time specific for the coronavirus are as follows:
- Aerosol: up to 3 hours
- Copper: up to 4 hours
- Cardboard: up to 24 hours
- Stainless steel: 2-3 days
- Plastic: 2-3 days
The coronavirus weakness: Soap
Lucky for us, the Coronavirus does have a nemesis; soap. You have undoubtedly heard many infectious disease experts tout the benefit of handwashing. This may seem trivial to some, but it is critical to our well being at all times but especially during a respiratory disease epidemic.
How does soap kill the coronavirus?
It’s all about biochemistry! The New York Times, with contribution from Prof. Pall Thordarson, acting head of chemistry at the University of New South Wales, wrote a detailed article about the chemistry of how soap molecule destroys viruses that have a lipid outer layer.
First, it is important to understand that the coronavirus has a fatty outer envelope. Breaking this envelope splits the virus apart.
Each soap molecule has a hydrophilic (water-loving) tail and a hydrophobic (repels water) tail. When you wash your hands with soap and water, the soap molecules will wrap around the coronavirus. The hydrophobic tails of soap molecules avoid water and therefore try to escape water by squeezing into the outer lipid layer of the coronavirus, which is a forceful action that splits the coronavirus apart, thus killing the virus.
Wash your hands often and do it properly
Of course, you know how to wash your hands, but you probably could be washing them even better. Take a moment to watch the #SafeHands challenge by the World Health Organization where Dr. Tedros demonstrates how to wash our hands properly. You may actually be surprised at how many steps are required to properly wash your hands and fingernails. Don’t forget to use enough soap to make sure that you form a sudsy lather around those viruses so that they can be destroyed.
You can review hand washing tips by Health Canada here and by the Centers for Disease Control and Prevention here.