By Gu Yekai
Origin tracing of COVID-19 shall be conducted in multiple countries and regions based on extensive consultations among WHO member states, said a senior official of China’s National Health Commission (NHC) at a press conference on the COVID-19 origin-tracing work Thursday.
Zeng Yixin, deputy head of the NHC, said he was “shocked” to learn that an origin-tracing proposal released by the WHO last week has listed the hypothesis that violations of laboratory protocols in China could have resulted in the virus’ leak as one of the major research objectives.
“In some respects, this plan disrespects common sense and defies science. It is impossible for us to accept a plan like this,” he said during the news conference held by the State Council Information Office.
Up to now, none of the Wuhan Institute of Virology (WIV) staff members and postgraduate students have been infected by the novel coronavirus, the lab has not carried out the gain-of-function experiment on the pathogen, and there is no so-called artificial novel coronavirus in the WIV, he reiterated.
In addition, WHO experts concluded that lab leak is extremely unlikely after personally visiting the WIV, Zeng said, adding that such conclusion must be respected as the experts were elaborately selected by the WHO and are very authoritative and experienced in their respective fields.
On March 30 this year, the WHO officially released a report on the global tracing of COVID-19 origins. The China part of the report made a good start of the global tracing work, Zeng remarked. More and more scientific evidence indicated that the report is valuable, authoritative, and able to withstand the test of science and history. The conclusion of the report is science-based, and the report was also made upon scientific principles, he said.
Through joint efforts of scientists from multiple countries, positive progress has been achieved in the study into the origin of the coronavirus. Xu Nanping, vice minister of the Ministry of Science and Technology introduced that as of July 19, Chinese scientists had issued 225 papers on COVID-19 origin tracing in cooperation with research teams from the US, the UK, and other countries, and 352 papers had been released by domestic research teams. Besides, Chinese and US medical experts had convened six video conferences on epidemic prevention and control.
According to Xu, the COVID-19 information database established by China National Center for Bioinformation has collected and shared 2.53 million genome sequences, providing services for nearly 300,000 users in 177 countries and regions around the world.
Zeng said the Chinese government has always supported science-based origin tracing, but it opposes politicizing the work. The second-phase study shall be an extension of the first-phase one, and be conducted based on extensive consultations among WHO member states, he added.
What was done in the first stage of origin tracing, especially by those that have reached a clear conclusion, should not be repeated. What should be carried out is the origin tracing of early cases, molecular epidemiology, and intermediary hosts in multiple countries and regions based on extensive consultations among WHO member states, Zeng said.
At present, the academic community generally believes that the novel coronavirus originated from the nature. Wang Chen, president of the Chinese Academy of Medical Sciences and Peking Union Medical College said at the conference that cold chains remained an important transmission channel amid the epidemic, and the evidence chain of transmissions by cold chains is relatively substantial. Given global trade and exchanges of personnel and goods, the human-to-object transmission in cold chain environment has made pathogen transmission even more complicated. Wang suggested that cold chains should be a significant clue in ongoing virus origin tracing.
The appeal for launching wide-ranging investigations worldwide is becoming stronger, as more evidence pointing to earlier infections outside China has surfaced recently, said Liang Wannian, team leader from the Chinese side of the WHO-China team studying the origins of COVID-19.
For instance, a skin sample taken from an Italian resident in November 2019 yielded traces of the virus, and traces also were found in human sewage samples collected in Brazil in November 2019. The first infection in Wuhan was reported on Dec 8, 2019.
“These examples show that Wuhan may not be the ground zero for virus spillover,” he said, adding that the virus likely underwent a complicated transmission cycle between animals, humans and objects.
Studies of early patients, bio samples, genomic sequences, natural hosts, intermediate hosts and cold chain infection, cannot be conducted without joint efforts of multiple places worldwide, he noted.
Wang said origin tracing is complicated and diverse, adding that vision shall not be restricted, but broadened in order to find the origins of the coronavirus. It is important to get the direction of origins tracing multiple-site, multiple-orientation and systemic research and study around the globe, he remarked.