Coronavirus found in pangolin smuggled into China: study
According to the researchers, including those at the University of Hong Kong, the findings suggest that pangolins are a second mammalian host for coronavirus.
They said that the sale of pangolins in wildlife markets should be strictly prohibited to minimize the risk of future transmission of the virus to humans.
While the evidence suggests that bats may be the reservoir for the virus that causes the pandemic, SARS-CoV-2, the researchers said the identity of the intermediate host animals, which may have facilitated their transfer to humans, remains unknown. .
A seafood market linked to the first cases of the recent outbreak of respiratory disease was removed shortly after the outbreak began, the scientists said, preventing the search for the animal species that is the source of the coronavirus.
They said that a possible host are pangolins, the mammal most commonly illegally trafficked, used as food and in traditional medicine.
In the study, Yi Guan and colleagues analyzed samples taken from 18 Malay pangolins that were obtained from smuggling operations in southern China between August 2017 and January 2018.
They detected SARS-CoV-2-related coronaviruses in 5 of these animals.
In a subsequent analysis, they reported the presence of similar coronaviruses in three out of 12 additional animals seized in a second province in 2018, and in an additional animal from a third province from which a sample was collected in 2019.
The virus noted that the viruses isolated from these samples have a sequence similarity of approximately 85-92 percent with SARS-CoV-2.
The scientists said that a virus shows great similarity in the sequence of the receptor binding domain, a region that encodes the “peak” of the virus that facilitates entry into host cells.
However, they said that all the pangolin coronaviruses identified to date lack a specific alteration in their sequences that is observed in human SARS-CoV-2.
They said this creates uncertainty about its role in transmitting the new coronavirus to humans.
According to the researchers, pangolins are the only mammals that, apart from bats, have been infected with a SARS-CoV-2-related coronavirus.
According to the findings, they said there is a potentially important role for pangolins in the ecology of coronaviruses.
However, scientists said pangolins cannot be directly involved in the transmission of SARS-CoV-2 to humans.
They said these mammals should be handled with caution, suggesting that more control of pangolins is needed to understand their role in the emergence of coronaviruses with the potential to infect humans.
“The discovery of multiple lineages of pangolin coronaviruses and their similarity to SARS-CoV-2 suggests that pangolins should be considered as potential hosts in the emergence of new coronaviruses, and should be removed from wet markets to prevent zoonotic transmission,” they wrote. investigators. in the study.