Q and A with the experts: explaining the surface transmission of COVID-19

Thursday, May 14, 2020

Trevor Charles
Many COVID-19 cases have been reported through community transmission, with 81 per cent of COVID-19 cases in Canada likely spreading this way.

What can be done to track the spread of COVID-19 on surfaces in our community?

We asked Trevor Charles, Director of the Waterloo Centre for Microbial Research, and Biology Professor to help us understand the spread of this virus in communities.

COVID-19 is not an airborne virus, what does this mean for how it is transmitted?

The term “airborne” is considered different from droplet-based transmission, which is how COVID-19 is spread. Virus particles are transmitted in cough or sneeze droplets traveling through the air. The recommendation for keeping 2 meters apart is so that we aren’t as susceptible to these droplets spread by others.

The virus can get onto surfaces in two different ways, it could come from droplets landing on the surface, or it could start from someone with the virus touching their face, and then the surface. Once the virus is deposited onto a surface, other people pick the virus up from touching the surface, and then touch their face to get infected. This is why we are being told to not touch our faces, and to wash our hands frequently.

How do we monitor where the virus lives when it can be on any surface?

There is actually very little surface tracking being done. Right now, most of the tracking of the virus has been done by testing patients who have exhibited symptoms. The reason for this is that, with limited testing capacity, it is most critical to identify those who are symptomatic and are infected. Once testing capacity catches up, we will see more general testing including members of the general population who do not exhibit symptoms.

For a surface, it is possible to take a swab and test if the virus is present. This will be important for providing assurances that a hotel room, restaurant or nursing home has been sanitized and safe from infectious viruses. 

Why is tracking the virus globally important?

Global tracking allows everyone to have a better idea of what is happening with movement of the virus around the world so that we have a better warning system in place. The idea is that we would be able to have a much more rapid response if we keep up to date with world-wide surveillance.

We know that the spread of COVID-19 is directly related to travel, and some studies have shown that communities often have several introductions of the disease, including possibly different variants of the disease.