Chinanews.com, March 31. On the afternoon of the 31st, the Chinese expert group of the China-WHO Joint Research on the Traceability of the Novel Coronavirus held a press conference on the joint research report. Liang Wannian, the leader of the joint research Chinese expert group, is introducing the joint traceability research The main conclusion was that the large-scale test of animal products in the South China Seafood Market did not find a positive result.
In terms of the main conclusion, Liang Wannian introduced that a coronavirus with a high degree of similarity to the new coronavirus gene sequence was found in bats and pangolins, but the similarity is not enough to make it the direct ancestor of the new coronavirus.
Animals such as mink and cats are highly susceptible to the new coronavirus, suggesting that bats, pangolins or mustelidae, cats, and other species may all be potential natural hosts.
Through extensive early case surgery and process sample testing, it was found that a certain scale of transmission of the new coronavirus occurred in the Wuhan population in December 2019. The earliest case detected so far appeared on December 8, and the earliest case related to the South China Seafood Market appeared. On December 12, most of the cases were concentrated in the second half of December.
The South China Seafood Market is one of the outbreak points of the new crown epidemic, but at the same time, the spread may also occur in other places in Wuhan.
Environmental sampling and testing after the closure of the South China Seafood Market showed that the environment was generally polluted by the new crown virus, especially the aquatic product stalls.
It is suggested that this market may have the possibility of introducing viruses through cold chain products, animals or animal products contaminated by infected persons.
Large-scale testing of animal products in this market did not find positive.
For cold chain products, we have not yet conducted relevant tests.
No new coronavirus was found in bats in Hubei Province and a large number of livestock, poultry, and wild animals in various parts of China. No evidence of the new coronavirus circulating in livestock, poultry, and wild animals before and after the outbreak was found.
The joint expert group conducted a scientific assessment of the possibility of the new coronavirus being transmitted from natural hosts through cold-chain food, directly from natural hosts, through intermediate hosts, and laboratory transmission. The evaluation conclusions are divided into five levels. It is divided into five levels: extremely unlikely, impossible, possible, more likely, and very likely, which is a five-level classification.
The direct spillover of zoonotic diseases is regarded as a possible to more possible way, and introduction through intermediate hosts is regarded as a way from more likely to very likely. There is a range, especially for intermediate hosts. From more likely to very likely.
The introduction of products through the cold chain and food chain is regarded as a possible way; the introduction through the laboratory is regarded as an extremely unlikely way.
Liang Wannian said that the joint expert group has reached a consensus that, from a scientific point of view, these assumptions are not geographically restricted. The expert team has been adhering to the concept of openness from the very beginning, because the introduction of the virus, the introduction of the virus from animals to people, and the outbreak of the South China Seafood Market may have gone through a long time, or it may have been a long-distance movement. Including cross-border activities, so we need to have a broader vision, not limited to a certain place, but to focus on all parts of the world, and gather all kinds of information collected from various fields and channels around the world to help us better understand This virus, trace the source of the virus, and what happened before the outbreak in Wuhan.