Coronavirus particles on surfaces can remain infectious longer when temperatures drop in winter: study

Houston: Scientists used virus-like particles to predict how environmental factors affect the survival of the novel coronavirus on surfaces and found that the COVID-19 virus can remain infectious longer when temperatures drop in winter. Read Also – More than 50 percent of the Indian population expressed caution in taking the COVID-19 vaccine

According to the study, published in the journal Biochemical and Biophysical Research Communications, virus-like particles, or VLPs, “faithfully mimic the external structure of the SARS-CoV-2 virus.” Also Read – COVID-19: US FDA Expert Group Approves Modern Vaccine For Emergency Use

Researchers from the University of Utah in the United States said VLPs are hollow shells made of the same lipids and three types of proteins found in an active SARS-CoV-2 virus, but without its RNA genetic material that causes infections. Read also – Parliamentary Home Affairs Committee will hold meeting on COVID-19 situation | Here’s what to expect

“VLPs, however, do not possess a genome and therefore do not present infectious threats, which allows for rapid studies with reduced security requirements,” they wrote in the study.

In current research, scientists have tested virus-like particles on glass surfaces in both dry and wet conditions.

The researchers explained that the SARS-CoV-2 virus is commonly spread when an infected person expels tiny droplets of mucus-laden aerosols from the lungs via sneezing, coughing, or abrupt exhalation.

They said these droplets have a high surface-to-volume ratio and dry quickly, so both wet and dry virus particles come into contact with a surface or travel directly to a new host.

Using advanced microscopy techniques, the researchers observed how the structure of the VLPs changed under these changing conditions.

They exposed the VLP samples to various temperatures under two conditions: with the particles inside a liquid buffer solution and with the dried particles.

In both liquid and bare conditions, scientists found that raising the temperature to about 93 degrees Fahrenheit for 30 minutes degraded the external structure.

According to the researchers, the effect was stronger on dry particles than on those protected by liquids.

Conversely, they said particles in room temperature conditions or outside in cooler weather can remain infectious longer.

While the humidity likely affected the distance of the viral particles in the cough and sneeze aerosols into the air before they dried, the researchers saw minimal influence of humidity on the survival of VLPs on surfaces.

“When it comes to fighting the spread of this virus, it is necessary to fight each particle individually. And so you need to understand what causes each individual particle to degrade, “explained Michael Vershinin, co-author of the study at the University of Utah.

“What is surprising is how little heat it took to break them down: surfaces hot to the touch, but not hot. The packaging of this virus is very sensitive to temperature, “added Vershinin.

To remain infectious, the scientists said the SARS-CoV-2 membrane needs a specific network of proteins arranged in a particular order.

When that structure falls apart, they said it becomes less contagious, suggesting that when temperatures start to drop in winter, particles on surfaces may remain infectious for longer.

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