According to the study, published in the journal Research Biochemical and Biophysical Research, virus-like particles, or VLPs, “faithfully mimic the extracellular structure of the SARS-CoV-2 virus.”
The researchers from the University of Utah in the USA said that the empty shell VLPs are made with the same lipids and three types of proteins as present in the active virus SARS-CoV-2, but without its RNA genetic material that causes infections.
“However, the VLPs do not have a genome and therefore do not pose an infectious threat that enables rapid studies with lower safety requirements,” they wrote in the study.
In the current research, the scientists tested the virus-like particles on a glass surface under dry and humid conditions.
The researchers explained that the SARS-CoV-2 virus is commonly spread when an infected person releases tiny droplets of aerosol from the lungs through sneezing, coughing or sneezing. send out suddenly.
They said these droplets have a high surface-to-size ratio and dry quickly – so both wet and dry viruses come into contact with a surface or travel directly into a new host.
Virus particles in room temperature or outdoors in colder weather can last longer.
Using advanced microscopy methods, the researchers observed how the structure of the VLPs changed under these variable conditions.
They extracted VLP samples to different temperatures under two conditions – with the particles inside a melting buffer solution, and with the grains dried out.
In a melting and bare state, the scientists found that raising the temperature to about 93 degrees Fahrenheit for 30 minutes reduced the outer structure.
According to the researchers, the effect was stronger on the dry grains than on those under liquid protection.
In contrast, they said, grains in room temperature or outdoors in colder weather may stay infectious longer.
Although humidity may affect the distance traveled by the virus particles in cough and sneezing aerosols in the air before drying out, the researchers found little effect of humidity on the survival of the virus. Surface VLPs.
“When it comes to fighting the spread of this virus, you have to fight with each grain individually. And so you have to understand what causes each individual grain. decline, “explained Michael Vershinin, co – author of the study from the University of Utah.
“What is surprising is how little heat is needed to break down a surface that is warm to the touch, but not hot. The packaging of this virus is very sensitive to temperature,” Vershinin said.
To stay infectious, the scientists said that the SARS-CoV-2 membrane requires a specific network of proteins arranged in a specific order.
When that structure falls apart, they said it will become more infectious, suggesting that as temperatures begin to fall in winter, surface particles may remain infectious longer.