The lead investigator for the WHO mission, Peter Ben Embarek, told CNN in an extensive interview that the mission had found several signs of its wider spread in 2019, including for the first time identifying more than a dozen species of the virus in Wuhan. already in December. The team also had the opportunity to speak with the first patient Chinese officials who said they were infected, an office worker in his 40s with no travel history, reported being infected on December 8.
The slow emergence of more detailed data collected from WHO’s long-awaited trip to China may add to the concerns of other scientists studying the origins of the disease that may have spread in China long before the first official emergence occurred in mid-December. .
Embarek, who has just returned to Switzerland from Wuhan, told CNN, “The virus was widely circulating in Wuhan in December, which is a new finding.”
The WHO food safety specialist added that in December 2019, the team had received 174 cases of coronavirus in and around Wuhan from Chinese scientists. Of these, 100 had been confirmed by laboratory tests, he said, and another 74 by the patient’s clinical diagnosis. symptoms.
Embarek said it was possible that this higher number of likely serious cases noticed early on by Chinese doctors meant the disease could have affected an estimated more than 1,000 people in Wuhan in December.
“We haven’t made models of it since then,” he said. “But we know … in large numbers … of the infected population, about 15% end up in severe cases, and the vast majority are mild cases.”
Embarek said the mission – which consisted of 17 WHO scientists and 17 Chinese – had expanded the type of genetic material of the virus they examined in early cases of coronavirus in December. This allowed them to look at partial genetic samples rather than just complete samples, he said. As a result, they were able to collect 13 different genetic sequences of the SARS-COV-2 virus for the first time as of December 2019. The sequences, if examined with broader patient data in China in 2019, could provide valuable clues about geography. and timing of the outbreak before December.
Embarek said, “Some of them are from the markets … Some of them are not connected to the markets,” including the Huanan fish market in Wuhan, which is believed to have played a role in the initial spread of the virus. “This is something that we discovered as part of our mission … part of the interaction we all had together.”
Variants ask bigger questions
Changes in the genetic makeup of a virus are normal and normally harmless, and occur over time as the disease propagates and propagates between humans and animals. Embarek declined to draw any conclusions about what the 13 tribes might have meant for the history of the disease before December.
But the discovery of so many different variants of the virus could indicate that it has been circulating for longer than just that month, as some virologists have suggested before. This genetic material is probably the first physical evidence to emerge internationally to support such a theory.
Prof. Edward Holmes, a virologist at the University of Sydney, Australia, said: “ Since there was already genetic diversity in SARS-CoV-2 sequences sampled from Wuhan in December 2019, it is likely that the virus was circulating for a while . longer than that month alone. ”
Holmes, who has extensively studied the virus’s emergence, said these 13 sequences may indicate that the virus had not spread for a while before the December outbreak in Wuhan. “These data are consistent with other analyzes that the virus emerged in the human population earlier than December 2019 and that there was a period of cryptic transmission before it was first discovered in the Huanan market.”
The WHO team held a three-hour press conference with their Chinese counterparts in Wuhan last week to present their findings. Since then, more details have slowly emerged about the precise data they could – and sometimes not – have access to.
Embarek said the mission was analyzed by Chinese scientists of 92 suspected Covid-19 cases from October and November 2019 – patients with Covid-like symptoms and critically ill. The WHO team asked these 92 to be tested for antibodies in January of this year. Of these, 67 had agreed to be tested and all turned out to be negative, Embarek said. He added that further testing was needed as it remains unclear whether antibodies are still present in former Covid-19 patients a year later.
But the way these 92 cases were spread over those two months and geographically across Hubei intrigued Embarek, too, he said. Embarek said the 92, as presented to the WHO team, did not emerge in clusters, as is common in disease outbreaks. Instead, they were spread in small numbers over both months and across the entire Hubei province, where Wuhan is located.
“There was no clustering in certain places,” he said. “That would have been picked up.” It remains unclear whether these 92 cases were related to the coronavirus, and what this lack of clustering might indicate.
Embarek also said the mission was able to meet the first Covid-19 patient that China said they knew. The man, a Wuhan resident in his 40s, has not been identified and had no recent travel history.
“He has no connection with the markets,” said Embarek. ‘We also spoke to him. He has a very – in a sense – boring and normal life, no hiking in the mountains. He was an office worker at a private company. ‘
China promises cooperation
China has promised transparency in the WHO’s investigation. Responding to US criticism that it should provide access to previous raw data, the Chinese Embassy in Washington DC said: “What the US has been doing in recent years has seriously undermined multilateral institutions, including the WHO, and international cooperation on COVID-19, ”a spokesman for the Chinese embassy in the United States said in the statement.
“But the US, pretending none of this has ever happened, is pointing the finger at other countries that have staunchly supported the WHO and the WHO itself,” the statement said.
The WHO team hopes to return to Wuhan in later months to continue its research, Embarek said, although he was unable to provide concrete dates for a confirmed trip.
He said the team hopes to urgently investigate biological samples that the experts say were not available to them on this maiden trip, specifically thousands of samples from Wuhan’s blood donor bank that are two years old.
“There are about 200,000 samples available there that are now protected and can be used for a new set of studies,” Embarek said. “It would be great if we could [work] with that.”
Embarek said there could be technical difficulties accessing those samples. “We understand that these samples are extremely small samples and are only used for litigation,” he said. “There is no mechanism to allow for routine studies with such samples.”
He said some other biological test samples that might have proved useful during the Wuhan mission were not available to them either. “Many of the samples are discarded after several months or weeks, depending on the purpose for which they were taken,” he said.
Embarek said the circumstances of the mission – from intense quarantine periods and social aloofness – had led to some frustrations, along with the global scrutiny of her behavior and findings.
“We worked closely together for a month among two groups from a large group of scientists,” he said. ‘And of course it is once in a while … you get – as always, between passionate scientists – heated discussions and then discussions about this and that.
“Remember, we’ve had the entire planet on our shoulders 24 hours a day for a month, which doesn’t make the work of scientists any easier.”