Some modern rodent populations could be asymptomatic carriers of SARS-like coronaviruses, according to the study’s authors.
A new study, published in the journal PLOS Computational Biology, suggests that rats could be asymptomatic carriers of SARS-like viruses, which means the ‘next COVID-19’ could emerge from rats.
Princeton University researchers examined the genomes of numerous mammalian species, focusing on the receptors that SARS viruses bind to.
They discovered that some rat species had been repeatedly exposed to SARS-like coronaviruses in the past, causing them to develop resistance.
If we talk about the virus that causes COVID-19 infection, SARS-CoV-2, is zoonotic, meaning it spreads from a non-human animal to humans.
Furthermore, an earlier study has shown that Chinese horseshoe bats may harbour a large number of SARS-like viruses without developing severe symptoms.
Identifying animals with similar defenses against such diseases — and hence serve as viral reservoirs — is critical for preventing future pandemics.
“Our study suggests that ancestral rodents may have had repeated infections with SARS-like coronaviruses,” wrote the study authors in their paper.
As a result of these infections, they are likely to have developed “some form of tolerance or resistance to SARS-like coronaviruses as a result of these infections.”
“This raises the tantalizing possibility that some modern rodent species may be asymptomatic carriers of SARS-like coronaviruses — including those that may not have been discovered yet.”
Dr. King and Professor Singh investigated the so-called ACE2 receptors that SARS viruses employ to enter mammalian cells, characterizing the receptors’ evolution across different mammalian species.
The researchers discovered that monkeys and other mammals not previously identified as SARS hosts had no evidence of historical adaptation in the ACE2 receptors, which makes us vulnerable to symptomatic cases of the disease today.
Both genomic examination of rats, however, revealed a pattern of rapid development in the ACE2 binding interface, as evidenced by a larger diversity in the amino acid sequences that code for the receptor.
This shows that some rodent species were likely repeatedly exposed to SARS-like coronaviruses throughout their history, and as a result, they may have developed a tolerance to these diseases.
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