SARS-CoV-2 related viruses found in trade-confiscated pangolins in Vietnam

SARS-CoV-2 related viruses found in trade-confiscated pangolins in Vietnam
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Beijing: Pangolins confiscated from the illegal wildlife trade in Vietnam host SARS-CoV-2 related coronaviruses, according to a study which suggests that the risk from trade in the animals goes beyond markets in China.

A team led by researchers from the Wildlife Conservation Society (WCS) noted that previously, only pangolins confiscated in China had tested positive for SARS-CoV-2 related coronaviruses.

The study, published in the journal Frontiers in Public Health on Wednesday, provides further evidence that the transnational nature of the wildlife trade can facilitate coronavirus and other viral transmission and amplification along the trade chain.

It also supports previous research which found that pandemic and epidemic prevention must also be focused on pathogen spillover from wildlife.

The researchers detected SARS-CoV-2 related coronaviruses, circulating in Sunda pangolins confiscated from the illegal wildlife trade in Vietnam.

Their analysis revealed that the coronaviruses identified in these pangolins were closely related to those previously detected in the animals confiscated from the illegal wildlife trade in Yunnan and Guangxi provinces, China.

"We know that SARS-like coronaviruses -- SARS-CoV-2 and SARS-CoV-1 -- can cause serious disease in humans, said the study's lead author, Nguyen Thi Thanh Nga of WCS's Vietnam programme.

"This study confirms the presence of coronaviruses in the SARS-CoV family in trafficked pangolins in Vietnam. Eliminating the trade in pangolins and other wild mammals and birds will eliminate this high-risk pathway for viral spillover and pathogen emergence," Thi Thanh Nga said.

All four species of Asian pangolins, including the Sunda and Chinese pangolin are considered Endangered or Critically Endangered across their geographic range.

The researchers tested specimens from a total of 246 pangolins from wildlife confiscation events that occurred in Vietnam in the years 2016 to 2018.

They found that specimens collected from seven individual pangolins in 2018 tested positive for a SARS-CoV-2 related coronavirus.

In addition to testing pangolins for SARS-CoV-2 related coronaviruses, the researchers reviewed media reports of pangolin trafficking cases involving Vietnam between 2016 and 2020.

Multiple pangolin confiscation events sampled in Vietnam involved other live wildlife including a mix of non-human primates, reptiles, and birds.

The findings support long-held concerns that the live wildlife trade, moving wild animals out of their natural habitats and into human dominated landscapes and large urban centres, poses a serious and increasing risk of initiating epidemics in human populations, the researchers said.

The study also indicates that current international recommendations are too narrowly focused on open markets and do not address the much longer wildlife supply chains, trade of both legally and illegally sourced wildlife from its source.

The research highlights the need for wildlife trade policy reform to curb the risks of future pandemics.

It also suggests mitigation measures must consider that the wildlife trade spillover interface contains novel viruses, which are not detected with current sample screening practices or procedures.