Rodents may be asymptomatic carries of SARS-like viruses, a study has warned — meaning the the ‘next COVID-19’ may well come from rats.
Researchers from Princeton University performed a genomic analysis of various mammal species, looking specifically at the receptors that SARS viruses bind to.
Researchers found evidence suggesting that certain rodent species were previously exposed to SARS virus-like coronaviruses. This likely led to them developing a degree of resistance.
SARS-CoV-2 — the virus that causes COVID-19 infection — is ‘zoonotic’, meaning that it jumped from a non-human animal into humans.
And previous research has shown that Chinese horseshoe bats can play host to numerous SARS-like without themselves showing extreme symptoms.
Identifying animals that may have similar protections against such infections — and could thus serve as viral reservoirs — is vital for preventing future pandemics.
Rodents may be asymptomatic carries of SARS-like viruses, a study has warned — meaning the the ‘next COVID-19’ may well come from rats, like the one pictured (stock image)
Mona Singh, a computer scientist at Princeton University in New Jersey and Sean King, a molecular biologist.
The duo stated in their paper that they found evidence suggesting that an ancestral rodent may have been exposed to SARS-like coronaviruses multiple times.
They suggested that this may have enabled them to develop’some kind of tolerance or resistance to SARS-like Coronaviruses.
‘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.‘
In their investigation, Dr King and Professor Singh studied the so-called ACE2 receptors that SARS viruses use to gain entry into mammalian cells — characterising the evolution of the receptors across different mammal species.
The team found that primates and other mammals not already known to be SARS hosts tended to have little evidence of past adaptation in the ACE2 receptors, which is what today leaves us vulnerable to symptomatic cases of the disease.
Among rodents, however, the duo’s genomic analysis exposed a pattern of rapid evolution in the ACE2 binding interface — evidence by a greater diversity in the amino acid sequences that code for the receptor.
This suggests that some rodent species were likely exposed to SARS-like coronaviruses repeatedly over the course their evolution and, as a consequence, that they may have acquired a form of tolerance to these types of infections.
In their investigation, Dr King and Professor Singh studied the so-called ACE2 receptors that SARS viruses uses to gain entry into mammalian cells — characterising the evolution of the receptors across different mammal species. Pictured: a SARS-CoV-2 spike protein (red) latched on to an ACE2 receptor (blue), letting it penetrate the cell (as seen in the background)
It will be vital to keep exploring the adaptations of coronavirus host animals. […]”To understand how SARS-like viruses may have been transmitted to animals, the team began.
Such studies, they continued, will also aid us in ‘finding those that are vulnerable symptomatic hosts, as humans have unfortunately proven to be.’
The full findings of the study were published in the journal PLOS Computational Biology.