Over time, we learn more and more about the coronavirus. Australian researchers have recently made an interesting finding. The SARS-CoV-2 virus, which causes COVID-19, stays on surfaces for 28 days under certain conditions.
To prevent the disease, Accent is often done on proper ventilation of closed spaces and aerosol particles (drops containing the virus released when coughing or talking), although we must not forget that the source of infection can also be the surface.
While the results of this study are important, this does not mean that the whole house should be washed with alcohol immediately. Let us first consider the experiment directly.
The researchers placed the SARS-CoV-2 strain in a special solution that is qualitatively similar to human saliva. The final virus concentration in this solution was 4.97 × 107 / ml. The researchers said that such concentrations of the virus in saliva are quite virulent and it is similar to the saliva of an infected person.
The scientists then placed the virus solution on various surfaces, such as iron, glass, cotton, paper, etc., and waited for it to work. It was found that after the solution “dried”, the virus remained on virtually all of the above surfaces for 28 days. The exception was cotton, on which infected particles could no longer be observed after 7 days.
“For context, the same experiment was conducted on the flu virus, and it lasted 17 days on the surface, which once again indicates the resistance of SARS-CoV-2,” said Debbie Eagles, co-author of the study.
We did not mention one important circumstance of the study: the experiment was conducted in complete darkness, ie in the absence of ultraviolet radiation. This means that the resistance of the virus may be different beyond laboratory conditions.
Scientists do not yet know how many viral particles are needed to infect humans. However, researchers suggest that it is quite possible to disperse the high virulence solution from the surface.
The role of temperature in the spread of the virus is likely to be less noticeable, as the pandemic has proved devastating even in hot countries. It is expected that India, in cases of coronavirus, will soon overtake the US.
The scientists point out the circumstance that the above experiment was not conducted on real saliva. “Human saliva contains a lot of enzymes that break down the virus,” said Ron Eccles, a researcher at Cardiff University.
“In my opinion, infectious viruses only last a few hours on the surface, not a few days.”
The above research has become an excuse for unfounded panic for many. The main route of transmission of the virus is from person to person. That is, the virus is primarily spread through saliva, which is excreted when coughing and talking. It is quite easy to clean the virus from the surface with a 70% alcohol solution.