The new coronavirus is "very unlikely" to pass through the laboratory

Xinhua News Agency, Beijing, March 30 (Reporter Ying Zhang) The China-WHO Joint Research Report on the Traceability of the New Coronavirus was officially released in Geneva on the 30th.

4 ways, 5 levels

From January 14th to February 10th this year, 17 Chinese experts and 17 foreign experts formed a joint expert group, which was divided into three working groups: epidemiology, molecular traceability, and animal and environment, which was carried out in Wuhan for a period of 28 days.

Based on the existing scientific evidence and findings, the joint expert team conducted a qualitative risk assessment on the possibility of the introduction of the new coronavirus into the four human transmission routes, and used "very unlikely", "impossible", "probable", "more likely" and "very likely".

The report believes that the new coronavirus is "probably to more likely" to be transmitted directly from the original animal host, "more likely to very likely" to be introduced into humans via an intermediate host, "probably" to be transmitted to humans through cold chain food, and "very unlikely" to be transmitted to humans through laboratory events .

The original source is still a mystery

In order to detect and confirm early cases of COVID-19, the Epidemiology Working Group evaluated the surveillance data on the incidence of respiratory diseases in Wuhan and surrounding areas at the end of 2019.

An evaluation study of more than 76,000 respiratory disease case records in 233 medical institutions in Wuhan two months before the outbreak of the new crown epidemic concluded that none of these cases was caused by the new crown virus infection.

The study also found that many early cases were related to the South China Seafood Market in Wuhan, but there were also many cases related to other markets, and some early cases were not related to any market.

Potential early transmission in other countries

The Molecular Traceability Working Group analyzed the genome data of viruses collected from animals.

The working group also conducted an in-depth analysis of the sequence data of virus samples collected from December 2019 to January 2020 to understand the diversity of virus sequences in the first phase of the outbreak.

The working group also evaluated published research data in different countries, which showed that the spread of the new coronavirus generally precedes the initial detection of the local case several weeks.

The relationship with the cold chain is not yet clear

The Animal and Environment Working Group did not find the presence of the new coronavirus in the sampling and testing of wild animals in China.

As of the time the South China Seafood Market was closed, environmental sampling analysis showed that 73 of the 923 environmental samples in the market tested positive for the new crown, indicating that the virus's environmental pollution is widespread, and the conclusion that the new crown virus may be transmitted to humans through contaminated products Consistent.

It has been found that the new coronavirus can be present in frozen food, packaging and cold chain products.

The report puts forward recommendations for the next step of the joint expert group’s research, including the establishment of a globally unified database, the continued search for possible early cases in a wider range of the world, and the search for animal species that may be the host of the virus by global scientists in multiple countries and locations to further understand The role of cold chain and frozen food in the process of virus transmission, etc.