Humans, followed by ferrets and, to a lesser extent, cats, civets and dogs are the animals most likely to be infected with the new coronavirus, according to a new study that analyzed ten different species for their susceptibility to the virus it causes. COVID-19. .
The findings, published in the journal PLOS Computational Biology, found that ducks, rats, mice, pigs, and chickens had lower or no susceptibility to coronavirus compared to humans, while cats, ferrets, civets, and dogs have documented cases. of SARS. CoV-2 virus infection. “Knowing which animals are susceptible to SARS-CoV-2 helps us prevent the accumulation of animal reservoirs from which the coronavirus can re-emerge at a later date,” said Luis Serrano, co-author of the study from the Center for Genomic Regulation (CRG ). in Barcelona, Spain.
“Our findings offer a clue as to why minks, which are closely related to the ferret, are being infected with the disease, which is likely to be made worse by their crowded living conditions and close contact with human workers,” Serrano said.
While the scientists also found potential susceptibility in cats, they said felines do not coexist with humans under the same conditions as other animals, possibly explaining why there are no known cases of people being infected by their pets.
In the study, the scientists used computer models to test how the coronavirus uses its spike proteins, which protrude from the surface of the virus, to infiltrate the cells of different animals.
Citing previous research, they said the main entry point on a cell’s surface is the ACE2 receptor, which binds to the spike protein through a lock and key mechanism. While there are many different variants of ACE2 within human populations and in different species, the scientists said that the types of ACE2 receptors in humans, ferrets, cats, dogs, and civets have the highest binding affinities for the viral spike protein, while mice, rats, chickens and ducks have little binding energy.
However, the scientists said that binding affinity alone is not sufficient to measure a cell’s susceptibility to infection.
The researchers also tested how efficient the coronavirus is at controlling cellular machinery in different species once it enters, also known as the codon adaptation index.
According to scientists, the more efficient this process, the better the coronavirus will be able to create the proteins it needs to replicate. They said that humans, chickens and ducks have the highest codon adaptation index, while the other species are worst adapted. Considering both binding affinity and this index, the researchers concluded that humans, followed by ferrets, cats, civets, and dogs, are the animals most susceptible to coronavirus infection.
They also found that different human variants of ACE2 showed differences in stability and binding to the spike protein, a sensitivity that scientists believe may be the basis for why some people suffer severe COVID-19 symptoms. “We have identified mutations in protein S that dramatically reduce the ability of SARS-CoV-2 to enter the cell, protecting the host from capture by COVID-19,” said study co-author Javier Delgado of CRG.
“We are now designing miniproteins from the human ACE2 protein to ‘distract’ the virus’s attention from entry into cells and block an infection. If new mutations of the viral spike protein emerge, we could design new variants to block them, ”Delgado added.
The researchers believe that understanding the infectivity of SARS-CoV-2 in different species can better inform public health measures, help reduce human contact with other susceptible animals, and prevent possible prolongation of the pandemic. (PTI)