As the coronavirus continues to evolve, the scientific and public health focus has been on new variants in which some mutations make the virus more contagious, or even more deadly.
These changes in the virus are all that scientists call point mutations, replacing one little bit of genetic code with another. Coronaviruses as a group are not known to mutate rapidly, but the pandemic caused by the SARS-CoV-2 virus means that millions and millions of people are infected by billions and billions of virus particles, which offers countless chances for change.
However, there is another more important way in which coronaviruses change. Individual viral particles exchange larger portions of genetic material with another virus. If two different types of coronavirus live in the same cell, the result may not be a new variant, but a new species.
Three researchers from the University of Liverpool who wrote in the journal Nature Communications predicted from a computer analysis that such events were much more likely than previously thought, and recommended monitoring target species after possible emergence of new ones. coronavirus diseases to watch.
The work has shown in some directions where scientists are already mindful. They identified the smaller Asian yellow bat and the larger and intermediate horseshoe bats as animals where more likely to recombine. But their analysis also pointed to animals that scientists have focused less on, such as the common pig, than a creature that needs to be monitored.
Marcus SC Blagrove, a virologist who co-authored the report with Maya Wardeh, who specializes in computer analysis of the spread of animal diseases, and Matthew Bayliss, a veterinary epidemiologist, said coronaviruses are known for “swapping large chunks everywhere.”
The emergence of new diseases through this process is not common, because an animal must be infected simultaneously with two different types of coronaviruses.
Jeremy Luban, a virologist at the University of Massachusetts, said that such a double infection with two types of viruses repeating in one cell had not yet been documented in humans. But exactly such a recombination is how SARS apparently originated, and researchers think that SARS-CoV-2 may also be the result of the combination of two viruses.
Dr. Luban said he believes “this kind of work is extremely important” because it can come with surprising insights that can follow experiments and fieldwork.
The group of researchers in Liverpool used a kind of computer analysis called machine learning to look at a number of different data points, including the genetic structure of coronaviruses and mammalian species, as well as their behavioral similarity and geographical proximity to make predictions. had.
They predict that 40 times as many mammalian species may be infected with four or more different species of coronaviruses as are currently known, and that up to 126 species of mammals may be susceptible to infection by SARS-CoV-2.
As a reality test, they pointed out that their analyzes correctly predicted some known associations of animals and viruses. The modeling highlights the palm clinkers, the animal from which it appears that SARS has spread to humans as a potential focal point for evolution of the coronavirus.
In general, they warned that the possibility of recombination leading to the emergence of a new dangerous coronavirus is highly underestimated.