The World Health Organization said on Tuesday that the original animal carrier of COVID-19 has not yet been identified, as the organization ruled out that a ab leak caused the outbreak.
The remarks were as WHO held a press conference in Wuhan after spending four weeks in the city investigating the origins of the virus.
According to Liang Wannian, a Chinese expert from Tsinghua University, bats and pangolins have been ruled out as the animal reservoir for COVID-19.
“Coronaviruses most highly related to SARS-CoV-2 are to be found in bats and pangolins, suggesting they could be the reservoir of the virus that causes COVID-19, on the basis of high similarity and sequences between the standard viruses and SARS-CoV-2. However, the viruses identified so far from neither of these species are sufficiently similar to SARS-CoV-2 to serve as direct progenitor of the SARS-CoV-2,” Liang said at a press conference of the WHO’s expert team.
However, Peter Ben Embarek, a WHO expert specializing in food safety, said the investigation to identify the origins of the coronavirus points to a natural reservoir in bats, although it’s unlikely that they were in Wuhan.
There is no evidence of COVID-19 circulation in any animal species in China in late 2019, Embarek added.
“It has not been possible to pinpoint any animal species as a potential reservoir for this disease, and they indicate that currently and also back in 2019 it does not look like there was circulation of the virus in any animal species in the country,” the expert said.
He also said that the COVID-19 outbreak was most likely caused by introduction through intermediary host species, while a laboratory leak is extremely unlikely to have triggered the outbreak.
“We identified four main hypotheses or groups of hypotheses on how the virus could have been introduced in the human population: direct zoonotic spillover; introduction through intermediary host species; food chain, frozen food products, surface transmission; and finally a laboratory-related incident…Our initial findings suggest that introduction through an intermediary host species is the most likely passway and one that will require more studies and more specific targeted research … The findings suggest that a laboratory incident hypothesis is extremely unlikely to explain the introduction of the virus into the human population,” Ben Embarek said.