During a press conference that marked the end of the World Health Organization’s 12-day China-based investigation into the coronavirus’ origins, WHO experts seemingly ruled out the possibility of a lab leak, instead asserting that the disease likely crossed into humans from animals. Establishing the virus’ origin is critical for future pandemic prevention, yet the Chinese government delayed the WHO’s investigation for over a year. When Australian Prime Minister Scott Morrison called for a WHO investigation in April 2020, the Chinese government launched a trade war against Australia and released a set of “14 disputes,” one of which was the call for an independent COVID-19 investigation. The Chinese government has placed significant restrictions on internal coronavirus research, even mandating that all medical research undergo government audit before publication. In recent weeks, Chinese foreign policy officials have claimed, without evidence, that the coronavirus was imported into China on frozen food. The opacity of the WHO’s investigation—team members did not give detailed interviews nor did they publish a schedule of their research itinerary—did nothing to dispel skepticism about the rigor of their work. At The New York Times, Javier C. Hernández reported on the investigation’s preliminary findings, some of which bolstered claims made by Chinese officials:

The W.H.O. team opened the door to a theory embraced by Chinese officials, saying it was possible the virus might have spread to humans through shipments of frozen food, an idea that has gained little traction with scientists outside China. And the experts pledged to investigate reports that the virus might have been present outside China months before the outbreak in Wuhan in late 2019, a longstanding demand of Chinese officials.

[…] The team also played down the idea that the virus might have leaked accidentally from a Chinese-run laboratory, a notion that even some skeptical scientists say is worth exploring. This theory is different than a widely discredited one pushed by some Republicans in the United States, which claimed that a lab in China manufactured the virus for use as a bio-weapon.

[…] The team did not report major breakthroughs but said it had found important clues. The virus was circulating in Wuhan several weeks before it appeared at the Huanan Seafood Wholesale Market, where some of the earliest clusters were initially reported, the experts said. It most likely emerged in bats and spread to humans through another small mammal, though the experts said they have not been able to identify the species. [Source]

– Wuhan local govt invites us to in-person presser at a different time to original WHO presser, says it cannot be streamed online
– Chinese state media announce they will stream the presser
– Hooray, the WHO's livestream link is working after all
(2/2)

— Yuan Yang (@YuanfenYang) February 9, 2021

One key goal was to understand what happened in early December 2019, says @Peterfoodsafety.
"Did we did we change dramatically the picture we had beforehand? I don't think so.
Did we improve our understanding? Did we add details to that story. Absolutely."

— Kai Kupferschmidt (@kakape) February 9, 2021

The frozen food import theory is controversial. Chinese state media have intimated that Wuhan’s initial outbreak was triggered by imported frozen food, but the WHO’s own website says, “There is no evidence to date of viruses that cause respiratory illnesses being transmitted via food or food packaging.” At The Wall Street Journal, Jeremy Page, Chao Deng, and Drew Hinshaw reported on the WHO team’s new embrace of the frozen-food hypothesis despite team-lead Ben Embarek’s previous rejection of the theory:

Another member of the WHO team, Peter Daszak, went further, telling reporters after the press conference that the focus of the investigation was shifting toward countries—especially in Southeast Asia—that could have been the source of animals or animal products sold in Wuhan’s Huanan Market.

“We’ve done a lot of work in China and if you map that back, it starts to point towards the border and we know there is very little surveillance on the other side in the whole region of Southeast Asia,” he said. “I think our focus needs to shift to those supply chains to the market, supply chains from outside China, even.”

[…] WHO researchers, including Dr. Ben Embarek, had previously deemed the likelihood of transmission to humans through frozen food as being very low. Only a handful of potential incidences of transmission have been documented during the past year.

“It seems to be extremely rare, and that being the source of the infection seems to be extremely rare, and that is happening in a world where you’re having half a million cases now every day,” Dr. Ben Embarek said in a Jan. 31 interview. “Transposing that onto last year in Wuhan when the virus is not widely circulating in the world and thinking that could be the introduction is not the most likely scenario.” [Source]

Daszak has deep connections to the Wuhan Institute of Virology (WIV) that he is investigating, having previously worked closely with the institution’s preeminent virologist Shi Zhengli on investigations into the 2003 SARS outbreak. In an interview with CNN, Daszak admitted that his evidence for the frozen-food theory comes entirely from the Chinese CDC’s research, not the WHO team’s own fieldwork.

A second major focus of the investigation was the Wuhan Institute of Virology, where Shi Zhengli led “gain of function” experiments on bat-based coronaviruses, which potentially make lab-based diseases deadlier or more contagious. Former United States Secretary of State Mike Pompeo claimed, without evidence, that the virus had leaked from the Institute after a lab accident. Citizen-journalist Zhang Zhan investigated the WIV before her imprisonment. The WHO team said that a lab leak was “extremely unlikely” based on conversations with scientists at the WIV. At The Washington Post, Gerry Shih and Emily Rauhala reported on the scientific community’s reaction to the WHO’s dismissal of the lab-leak theory:

“Just saying that they have really good safety protocols is not an answer in my view,” said Marc Lipsitch, a professor of epidemiology at Harvard’s T.H. Chan School of Public Health, who was not among the scientists on the trip. “That alone does not put my mind at rest.”

[…] “If the only information you’re allowing to be weighed is provided by the very people who have everything to lose by revealing such evidence, that just doesn’t come close to passing the sniff test,” said David A. Relman, a microbiologist at Stanford University.

Relman suggested that the WHO team should have sought complete, detailed records from the laboratories about their experiments and the raw genomic sequence data of their research going back a decade. [Source]

Team also looked at the BSL4 lab in Wuhan Institute of Virology and "it was very unlikely that anything could escape from such a place”, says @Peterfoodsafety.

— Kai Kupferschmidt (@kakape) February 9, 2021

Do I understand this correctly? (Emphasis: I have no comment/assertion on lab accident hypothesis.) The team is asserting that they can *rule out* lab screw-up but *not* frozen food? That it's plausible that SARS-CoV-2 was introduced into China through frozen food from elsewhere?

— zeynep tufekci (@zeynep) February 9, 2021

Chinese authorities are now calling for the WHO to search for the coronavirus’ origins outside of China’s borders. During the press conference, Liang Wannian of China’s National Health Commission, which led a team of 17 investigators attached to the WHO’s mission, claimed that the virus might have been spreading outside of Wuhan before December. The Chinese ambassador Cui Tiankai suggested that the WHO team investigate the United States, seemingly indicating he believed the virus started there. Foreign Ministry spokespeople have previously suggested that the virus originated in a United States military base. In a public letter, famed Chinese journalist Cheng Yizhong said, “to deny the virus’ origin is not only base and uncivilized, but is also equal to slandering the place where the virus appeared.” In a survey of Chinese medical practitioners, Global Times, a state-run tabloid, pushed the unfounded idea that the coronavirus was imported into Wuhan from a foreign country:

The WHO should conduct virus-tracing work in other countries, as it is a global pandemic, and the origins cannot be found in just a single place, Feng Duojia, president of the China Vaccine Industry Association, told the Global Times on Thursday. “Wuhan is just a stop for virus origin tracing, and those experts should not expect to find an answer here. Also, it is scientifically impossible, as there were cases found in other countries even before the outbreak in Wuhan was reported,” he said.

[…] “The WHO’s investigation of virus sources probably won’t come to anything if international experts did not go to other countries, because Wuhan is definitely not where the virus originated from,” Lu said.

[…] “Given more cases were found in other countries much earlier than in China, a key question that the WHO team needs to ask and get an answer after the Wuhan trip will be: How was the virus introduced into China, as it’s unlikely a domestically grown virus but one brought in by travelers or via other means,” Wang Guangfa, a respiratory expert at Peking University First Hospital, who went to Wuhan in the early stages of the outbreak, told the Global Times on Thursday. [Source]

The article was accompanied by a graphic presenting a revisionist timeline of the pandemic:

Meanwhile…Zeng Guang, the former chief epidemiologist at the Chinese CDC, says that the US should be focus of the search for origin of the coronavirus. "There also exists the possibility that the new coronavirus emerged in the US earlier than Wuhan." https://t.co/fixZQIw0fo

— Chris Buckley 储百亮 (@ChuBailiang) February 9, 2021

As his final point, Prof Liang explains the cold chain transmission mechanism at length. "Huanan has a substantial number of stores sell cold chain products…but it's not clear the initial [outbreak] can be mapped" to these stores.

— Gerry Shih (@gerryshih) February 9, 2021

WHO team members have denied any undue political interference from Chinese officials, and stood behind their research. In an interview with CBS’ Face The Nation, Maria Van Kerkhove, a leader of the WHO’s coronavirus team, said that the investigation was based on good science:

MARGARET BRENNAN: World Health Organization investigators a year after the outbreak began in China have now been allowed in to look at what happened on the ground. Is this just a show by the Chinese government?

DR. VAN KERKHOVE: No, it’s not. In fact, we have a team of 10 international scientists. You called them investigators, but indeed they’re- they’re scientists from a number of different technical fields, as well as people from WHO, my colleagues. And we have colleagues from FAO and OIE who are supporting the mission as well. And this is- these are studies that are ongoing to find the virus origins and understand the intermediate hosts. You know, what were the zoonotic origins of this pandemic? And this is really, really critical from a public health perspective so that we know and we can take steps further to prevent this from happening again. They’re very good discussions that are having on the ground. There are constructive exchanges between this international team from 10 different countries, as well as the Chinese counterparts, looking at the earliest cases, looking at studies from the markets. They’ve had visits to hospitals. They’ve had visits to two laboratories, including the Wuhan Institute of Virology, as well as visiting different levels of the Chinese Centers for Disease Control. So, we’re hoping for the reports as soon as possible, and that will be made available as soon as it can be. [Source]