https://youtu.be/X0dzqLuQPrU
Frequent outbreaks triggered by imported frozen products; reports suggesting traces of coronavirus found elsewhere earlier than Wuhan… so is COVID-19 outbreak in Wuhan also result of imported cold-chain products? Check GT special investigative report…
Italian newspaper Corriere Della Sera reported in November that a new coronavirus was circulating in Italy in September 2019, a study by the National Cancer Institute (INT) of the Italian city of Milan shows, indicating that the virus may have existed in Italy months before it was first detected in China.
The Italian researchers’ findings, published by the INT’s scientific magazine Tumori Journal, show 11.6 percent of 959 blood samples from healthy volunteers enrolled in a lung cancer screening trial between September 2019 and March 2020 had developed coronavirus antibodies well before February.
Peter Forster, a geneticist from Cambridge, also told the Global Times that he is not surprised that there might be cases earlier than China.
Foster suggests it is useful to think of three stages in the origins of the coronavirus: when and where did it cross the species barrier from bats to humans and when and where did it start spreading successfully among humans. “My dating suggests sometime between September and December 2019,” said the virologist, proposing finally to look at when the globally dominant infectious coronavirus subtype arose.
“Everyone agrees it was prominent in Northern Italy in February 2020. Some scientists said it came to Italy from China, but I am not so sure,” he said.
Evidence of both epidemiology and virology are needed to find out where the virus comes from, said the Beijing-based anonymous expert. If the pandemic originated from a certain place, there should be signs of an early outbreak. It is also possible that the virus already existed, but not seriously enough to cause an outbreak, he said, noting that there is only a small probability of the latter scenario, and no solid evidence to support it.
From a virology perspective, a full gene sequence of cases from that place should be obtained for observation and for determining when the virus was transmitted to this place via time and the virus’ variation point, said the expert.
“If we have doubts that the virus was originated from places other than Wuhan, we can compare its sequencing with the virus that was found in Wuhan. [We should] compare their homology and variability, to see if the virus found in other places is in its early stage, or it is evolved,” he said.
There are reports from several countries that early blood samples tested positive for the virus, but they can provide no evidence of the nucleic sequence, so the possibility of a false negative cannot be ruled out, said the anonymous expert.
He believes that if antibodies can be found in the blood serum, then the virus can also be found there. Even if the virus is not infectious anymore, it is easily detected, as its nucleic acid is protected by the coat of the virus and it is very stable and sensitive.
International cooperation urged
Although those virologists have pictured a clear route map to trace the origin of the virus, the real path to finding the origin is laden with difficulties.
The anonymous expert said that in terms of tracing the virus origin, the momentum for international scientists to cooperate has retrogressed compared with the pre-COVID-19 period.
“Scientists are reluctant to become involved in politics, they are eyeing international cooperation. Yet researchers from all over the world are acting with caution, avoiding troubles, and refusing casual communication. I don’t think it’s an ideal atmosphere for cooperation.”
This has drawn attention from international bodies. WHO Director-General Tedros Adhanom Ghebreyesus urged countries on November 30 not to politicize the hunt for the origins of the new coronavirus, saying that would only create barriers to learning the truth.
When talking to Tedros in September, director of China's National Health Commission Ma Xiaowei vowed to enhance cooperation with the WHO on virus prevention, origin tracing and vaccine development. China is pushing forward the work on the virus origin tracing, and is willing to strengthen cooperation and communication with the WHO, Ma said.
Chinese Foreign Ministry spokesperson Zhao Lijian said on November 24 that while tracing the origin domestically, China has been earnestly implementing WHA resolutions.
"We are the first to invite WHO experts in for origin-tracing cooperation." Zhao said, adding that "We hope all relevant countries will adopt a positive attitude and cooperate with WHO like China does, making contributions to global origin-tracing and anti-epidemic cooperation."
“International communication on the virus origin should be frequent and open for all. But some countries weighed in and complicated the issue,” said Yang, who noted that the world has achieved great progress in fighting COVID-19 in the past year, including treatment of the disease and vaccine R&D.
Tracing the virus origin should not be a battle against each other; instead, an information, data sharing mechanism is helpful to bring the virus under control, Yang said.
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