Experts at the Center for Genomic Regulation (CRG) have found out which species are most susceptible to SARS-CoV-2 infection. The results are published in the journal PLOS Computational Biology.
Studies have shown that ducks, rats, mice, pigs, and chickens have a lower susceptibility to infection than humans, or not at all.
“Knowing which animals are susceptible to SARS-CoV-2 helps us prevent later outbreaks of infection,” says Luis Serrano, ICREA research professor, CRG director, and senior author of the study.
In this article, ten species of living beings have been studied. Five of them – humans, cats, ferrets, civets, and dogs – have contracted SARS-CoV-2. There are no infection reports in the other five species – mice, rats, pigs, chickens, and ducks.
The researchers used computer simulations to test how the coronavirus uses its spike proteins, which protrude from the virus’s surface, to enter the cells of various animals. The main entry point to the cell surface is the ACE2 receptor, which binds to a spike protein. There are many different variants of ACE2 in human populations and different species. The researchers also tested the “codon adaptation index” of various species – how effectively the coronavirus hijacks a cell’s machinery after it has entered. The more efficient the process, the better the coronavirus can make the proteins it needs to replicate.
Humans, chickens, and ducks have the highest codon adaptation index, while other species are less adapted.
Looking at both the binding affinity and the codon adaptation index, the researchers concluded that humans, followed by ferrets, cats, civets, and dogs, are the most susceptible animals to infection with the coronavirus.
Understanding the infectivity of SARS-CoV-2 in different species can better inform public health measures, reduce human contact with other susceptible animals, and avoid the potential prolongation of the COVID-19 pandemic, the scientists conclude.