Hundreds of mammal species can serve as incubators for coronaviruses to mix with each other, forming new viruses and stimulating the future. pandemics, predicts a new study. These species include wild animals, such as bats and monkeys, as well as domestic animals, such as pigs and cats.
The study, published February 16 in the journal Nature communication, emphasizes the potential for coronavirus to infect a wide variety of hosts. In fact, the work identifies hundreds of animal species that can become infected with known coronaviruses, although many of these infections have not yet been observed in nature.
Coronaviruses form a large family of viruses that can infect birds and mammals; SARS-CoV-2, the virus that causes COVID-19, is only one member of the coronavirus family. For the research, the team drew the genetic sequences of 411 coronaviruses from GenBank, a National Institutes of Health database, and selected these sequences using a computer algorithm. The sequences represented 92 different species of coronavirus, while some species were represented by more than one virus strain.
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The algorithm predicted that on average each virus had more than 12 mammalian hosts. It was predicted that each selected animal species would, on average, be a potential host for more than five coronaviruses.
Animals that can host many coronaviruses are the biggest threat; when several coronavirus strains enter the same cell, their genes can be mixed and linked while repeating, thus generating new patches viruses.
It genetically card shuffling, known as ‘recombination’, can be especially dangerous if SARS-CoV-2 genes are exchanged with another coronavirus, the authors write. This is because the resulting virus may be just as contagious to humans as SARS-CoV-2, but may infiltrate additional tissues or cause worse diseases. The model identified 126 non-human species that could potentially house the SARS-CoV-2 and at least one other coronavirus, which could unfold this disturbing scenario.
“More astonishing than any individual animal was the wide variety of animals predicted to be large numbers of coronaviruses,” write the authors Maya Wardeh, a computer scientist, and Marcus Blagrove, a virologist from the University of Liverpool. England. a joint statement to Live Science. ‘Everyone knows this bats is important, but we found very high risk hosts throughout the mammals, including rodents, primates [and] ungulates. ‘
That said, just because two coronaviruses can infect the same animal does not mean they can and will recombine, said Arinjay Banerjee, a virologist at McMaster University in Ontario who was not involved in the study. Recombination requires that the viruses enter the same cell type and that the infections peak at the same time, including logistics. But the new study provides a useful list of mammalian species that should be monitored for coronavirus infections and recombination events in the future, he said.
A network of potential infection
To predict which mammals are likely to be coronavirus hosts, the authors used a computer algorithm which mapped the links between potential hosts and known coronaviruses. The algorithm analyzed known coronaviruses and looked at which animals they are known to infect. Other animals that were closely related, lived in similar habitats or ate the same diets were then looked at, as they probably suspected that they also contained similar populations in the coronavirus. The algorithm also compared the genome sequence of different coronaviruses, with the idea that closely related coronaviruses could probably infect similar hosts.
After these compounds were found, the algorithm determined which mammals could possibly contain many coronaviruses and thus be the focal points of coronavirus recombination.
The team selected 876 mammalian species using this algorithm, including 185 known coronavirus hosts. The remaining 691 species belonged to the same species as a known host. The algorithm tested potential links between these animals and the 411 coronaviruses for which the complete RNA sequence is already known.
“These 411 viruses contain all seven coronaviruses that are known to infect humans, as well as the complete range of other coronaviruses whose genomes are sequenced,” the authors said.
Although all sequences of SARS-CoV-2 were included in the analysis, they were treated as a single entity in the analysis. “SARS-CoV-2 variants are all very similar, with only relatively small mutations; we would not expect our results for the specific specifications of the host to differ between them,” the authors told WordsSideKick.
Of the 126 species identified as potential hosts for SARS-CoV-2, several animals had the highest risk of recombination. Some of these animals have been identified as possible recombination hosts for SARS-CoV-2, as well as for the related virus SARS-CoV, which caused outbreaks of severe acute respiratory syndrome in the early 2000s.
The Asian palm cookie (Paradoxurus hermaphroditus) was a predicted host for 32 coronaviruses, in addition to SARS-CoV-2. The larger horseshoe bat (Rhinolophus ferrumequinum) and intermediate horseshoe bat (Rhinolophus affinis), hosts were predicted for 67 and 44 additional coronaviruses, respectively, and the pangolien (Manis javanica) for 14.
In addition to these suspected hosts, the model highlighted wild animals that have not yet been linked to SARS-CoV-2 recombination. It has the smaller Asian yellow bat (Scotophilus kuhlii), chimpanzee (Pan troglodytes) and African green monkey (Chlorocebus aethiops). The common hedgehog (Erinaceus europaeus), European hurry (Oryctolagus cuniculus) and domestic cat (Happy cat) is also likely to host co-infection and recombination, the model predicted.
But the “most prominent result for a SARS-CoV-2 recombination host is the domestic pig (Sus scrofa“,” predicts that 121 coronaviruses will be in addition to SARS-CoV-2, the authors write.
“Given the large number of coronaviruses that predict our framework with which the pig may be infected, we would suggest that the pigs be monitored at ‘high risk’. [living conditions], “the authors told WordsSideKick. Pigs kept close to other high-risk farm animals, for example, would be considered high-risk, while pigs in isolation from other animals would have a relatively low risk, they said.
High-risk scenarios
The study also identified 102 potential species infected with SARS-CoV-2 and MERS-CoV, the coronavirus, which causes Middle Eastern respiratory syndrome (MERS). MERS has a much higher mortality rate than COVID-19, estimated at about 35%, so the recombination of these two viruses can be extremely dangerous, which can make the resulting virus highly transmissible and likely cause serious illnesses, the authors said.
The model also predicted possible interactions that did not include SARS-CoV-2 at all. The team found that many genetically diverse coronaviruses could potentially mix and exchange their RNA; For example, 291 mammalian species were predicted from coronaviruses from four or more different subgenera, a taxonomic subcategory below the genus and above the species.
However, coronaviruses of the same subgenus are likely to recombine as viruses from different subgenera, Banerjee said. ‘We do not know whether different subgenera would recombine; ‘it is unlikely, but it has not been demonstrated experimentally,’ he said.
The domestic pig, the lesser Asian yellow bat and the larger and intermediate horseshoe bats have all acted as likely hosts for these recombination events, but additional species also appear on the high-risk list. This especially includes the dromedary camel (Camelus dromedarius), a known coronavirus host and the primary transmitter of MERS-CoV to humans.
Looking ahead, the authors of the study plan to develop a similar model for bird species to see which birds may be a source of coronavirus recombination; known hosts of bird coronavirus contain the turkey (Meleagris gallopavo) and guinea fowl (Numida meleagris), inter alia, according to a 2005 report in Bird pathology. After collecting the data on birds, the team wants to model how often potential coronavirus hosts in the animal kingdom come into contact with each other.
“This will allow the estimation of the location where a host species is most at risk, and it could focus more specifically on ‘what and where’,” the authors said. In addition, they plan to include clinically relevant data in their predictions, and discuss which viruses are known to cause diseases in humans and what symptoms they cause.
For now, the likelihood of recombination in different types is uncertain, as well as the risk that these theoretical mash-ups could make people sick, Banerjee said. But “my take away from this manuscript is [to] “Extend surveillance to well-known and undervalued potential reservoirs of coronaviruses,” said Banerjee. reservoir for coronaviruses.
Such early identification of potential hosts for coronaviruses could help scientists develop targeted surveillance programs to capture recombination “as it happens and before a major outbreak,” the authors wrote. And in the event of an outbreak, scientists could easily refer to the record of coronaviruses found in high-risk animals to identify the new pathogen, Banerjee said.
Originally published on Live Science.