Infection prevention experts are calling COVID-19 an infodemic, meaning misinformation spreading quicker than the virus itself. Everyday we are reading updates on the increasing number of cases and deaths. We are unfortunately not talking about the positive: the increased number of cases who have recovered.
As more time passes, researchers are sharing and publishing more information about the virus itself. One of the exciting studies that is being published in the New England Journal of Medicine investigates the length of time that SARS-CoV-2, the virus that causes COVID-19 disease, can survive on surfaces. It is generally believed that COVID-19 is transmitted in droplet form after sneezing or coughing. The importance of this is that droplets are heavier and can only stay suspended in air for a short period of time before dropping to land on a surface. If you are close enough for the virus particles to reach you after someone coughs or sneezes, you can become infected.
The ability for the virus to survive in the air and on surfaces has a direct impact on its ability to transmit from person to person. The study investigated and compared SARS-CoV-2 and the original SARS virus to determine their aerosol stability and surface survival capability. When it came to stability of SARS-CoV-2 on surfaces, researchers looked at the ability to survive on the surface for up to 7 days. The testing conducted indicated that viable virus could be found on plastic and stainless steel for up to 72 hours. The virus was found to survive better (higher concentrations for longer) on plastic. On copper, SARS-CoV-2 did not survive past 4 hours and on cardboard, it did not survive past 24 hours. When it came to the viability of SARS-CoV-2 surviving as an aerosol, researchers used 3 hours as the point of time to test and found that viable virus was found in aerosols throughout the duration of the study.
Gaining clarity into SARS-CoV-2’s ability to survive on surfaces and after being “shed” via coughing and sneezing is an important piece of the puzzle. The shorter timeframe it can survive, the better our chance of stopping its spread. It’s important to understand that these tests were conducted under carefully controlled conditions in a lab. In the real world, where conditions (e.g. temperature, humidity and sunlight) can impact the ability to survive as well. For example, we know that sunlight can help in reducing the infectivity of viruses on surfaces.
The long and the short is we still have so much more to learn about this virus. There is speculation that infected people may be shedding the virus and infecting others before they even exhibit symptoms. If true, this certainly impacts the speed with which we can curb the pandemic. However, many countries are taking precautions such as cancelling large gatherings, closing schools and restaurants as well as asking for people to work from home and follow social distancing, all of which will help curb transmission. If the virus is only capable of surviving for 3 days as opposed to initial indications of much longer, then we can continue wage war against SARS-CoV-2 and be victorious by all working together.