BEIJING: The Chinese experts gave comprehensive and clear cut answers on the origin of COVID-19 during a conference held in Beijing by the State Council Information Office (SCIO) a couple of days ago.
The experts included Xu Nanping, Zeng Yixin, Wang Chen, Liang Wannian and others gave replies to the questions regarding the origin of coronavirus.
At the start Zeng Yixin said China had organised a multidisciplinary team to do a lot of work on origin tracing, despite arduous epidemic prevention and control tasks. It was on the basis of this work that our experts and the WHO experts to China discussed and jointly formulated the Terms of Reference (TOR) last July. Since then, China has carried out origin-tracing studies in strict accordance with the TOR.
The report is an account of the China part of the global study of the virus origins. The expert team reached the following conclusions. The coronaviruses found in bats and pangolins are most highly related to SARS-CoV-2 and share the highest homology with SARS-CoV-2 by sequencing. However, neither of the viruses identified so far from these mammalian species is sufficiently similar to SARS-CoV-2 to serve as its direct progenitor. Although the homology is high, there is still much difference. Based on research results in various fields, such as clinical epidemiology, zoology, and environmental testing, the joint study team assessed the likelihood of different possible pathways for the introduction of the virus. First, direct zoonotic spillover is considered to be a possible-to-likely pathway. Second, introduction through an intermediate host is considered to be a likely-to-very-likely pathway. To put it simply, this means the virus would have been transmitted from an animal reservoir to an intermediate host, followed by transmissions to humans. This is a likely-to-very-likely pathway.