Ancestral rodents possibly have been infected with SARS-like COVID-19 repetitively, which has made them form a fighting towards the pathogens, according to new research. This also means that they are likely to have no symptoms that carries SARS-like coronaviruses in them.
The findings of the research have been published in ‘PLoS Computational Biology Journal’ and has been conducted by Sean King and Mona Singh of Princeton University. The virus SARS-CoV-2 that causes coronavirus infection is of zoonotic origin–it jumped from a non-human animal to humans.
According to the earlier conducted researches, it has been found that Chinese Horseshoe bats are a host of numerous SARS-like viruses and that can tolerate these viruses without life-threatening symptoms. Identifying other animals that have improved tolerance mechanisms to coronaviruses is important for awareness of potential viral reservoirs that can spread new pathogens to humans.
In the new research, King and Singh performed an evolutionary analysis, across mammalian species, of the ACE2 receptors, used by SARS viruses to gain entry into mammalian cells. Primates had highly conserved sequences of amino acids in the sites of the ACE2 receptor known to bind SARS viruses. Rodents, however, had a greater diversity — and an accelerated rate of evolution — in these spots.
Overall, the results indicated that SARS-like infections have not been evolutionary drivers in primate history, but that some rodent species have likely been exposed to repeated SARS-like coronavirus infections for a considerable evolutionary period.
“Our study suggests that ancestral rodents may have had repeated infections with SARS-like coronaviruses and have acquired some form of tolerance or resistance to SARS-like coronaviruses as a result of these infections,” the authors said.
“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,” the authors added.
