As the coronavirus pandemic sweeps the globe, the biggest barrier impeding the fight is our lack of knowledge about how the virus works. A recent study examined the survivability of the new virus, SARS-CoV-2, on surfaces compared with its closest known relative SARS-CoV-1.
The study, published on 17 March in the New England Journal of Medicine specifically studied the aerosol and surface stability of the pathogen.
Five environmental conditions were tested; aerosols, plastic, stainless steel, copper, and cardboard. These environments are surfaces that are often encountered in medical and more casual settings.
Results
Viable SARS-CoV-2 entities were detected up to 72 hours after application to the plastic and stainless steel surfaces, though the levels were greatly reduced from the starting point.
Though still a metal, SARS-CoV-2 had a different reaction to copper with no viable levels detected after even four hours. SARS-CoV-1 took eight hours to be unviable on copper by comparison.
On cardboard the virus survived a shorter time than on plastic and stainless steel as expected. But there was a large difference between SARS-CoV-1 and SARS-CoV-2. SARS-CoV-1 became unviable on cardboard after just eight hours, while SARS-CoV-2 took 24 hours.
Cardboard is a very relevant surface to industry, as many packages are sent around the world in this medium
In an aerosol form the two virus both had similar half-lives of just over an hour.
So the newer virus does not appear to be as stable for as long on copper as its relative, but a fair bit longer on cardboard. Cardboard is a very relevant surface to industry, as many packages are sent around the world in this medium.
The scientists performing the study concluded: “We found that the stability of SARS-CoV-2 was similar to that of SARS-CoV-1 under the experimental circumstances tested. This indicates that differences in the epidemiologic characteristics of these viruses probably arise from other factors, including high viral loads in the upper respiratory tract and the potential for persons infected with SARS-CoV-2 to shed and transmit the virus while asymptomatic.”
The Rocky Mountain Laboratories team further explained the results infer that aerosol and fomite transmission of SARS-CoV-2 is plausible, since the virus can remain viable and infectious in aerosols for hours and on surfaces up to days.
For SARS-CoV-1 the transmission was associated with nosocomial spread and super-spreading events and it appears this pandemic, though far greater, echoes this method.