The hunt for the origins of COVID-19 has gone dark in China, the victim of political infighting after a series of stalled and thwarted attempts to find the source of the virus that killed millions and for months.
The meaningful domestic and international efforts to trace the virus from the first weeks of the outbreak, despite statements supporting open scientific inquiry, an Associated Press investigation found. That pattern continues to this day, with labs closed, collaborations shattered, foreign scientists forced out, and Chinese researchers barred from leaving the country.
The investigation drew on thousands of pages of undisclosed emails and documents and dozens of interviews that showed the freeze began far earlier than previously known and involved political and scientific infighting in China as much as international finger-pointing.
As early as Jan. 6, 2020, health officials in Beijing closed the lab of a Chinese scientist who sequenced the virus and barred researchers from working with him.
Scientists warn that willful blindness over the origins of the coronavirus leaves the world vulnerable to another outbreak, potentially undermining coordinated by the (WHO) set to culminate in May.
At the heart of the question is whether the virus jumped from an animal or came from a laboratory accident. A says there is insufficient evidence to prove either theory, but the debate has further tainted relations between the U.S. and China.
Unlike in the U.S., there is virtually no public debate in China about whether the virus came from nature or from a lab leak. In fact, there is little public discussion at all about the source of the disease, first detected in the central city of Wuhan.
Crucial initial efforts were hampered by bureaucrats in Wuhan trying to avoid blame who misled the central government; the central government, which muzzled Chinese scientists and subjected visiting WHO officials to stage-managed tours; and the U.N. health agency itself, which may have early opportunities to gather critical information in hopes that by placating China, scientists could gain more access, according to internal materials obtained by the AP.
In a faxed statement, China's Foreign Ministry defended China's handling of research into the origins, saying the country is , shared data and research, and "made the greatest contribution to global origins research." The National Health Commission, China's top medical authority, said the country "invested huge manpower, material, and financial resources" and "has not stopped looking for the origins of the coronavirus."
It could have played out differently, as shown by the , a genetic relative of COVID-19, nearly 20 years ago. China initially hid infections then, but WHO complained swiftly and publicly. Ultimately, Beijing fired officials and made reforms. The U.N. agency soon found SARS likely jumped to humans from civet cats in southern China and international scientists later collaborated with their Chinese counterparts to pin down bats as SARS' natural reservoir.
But different leaders of both China and WHO, China's quest for control of its researchers, and global tensions have all led to silence when it comes to searching for COVID-19's origins. Governments in Asia are pressuring scientists not to look for the virus for fear it could be traced inside their borders.
Even without those complications, experts say identifying how outbreaks begin is incredibly challenging and that it's rare to know with certainty how some viruses begin spreading.
"It's disturbing how quickly the search for the origins of [COVID-19] escalated into politics," said Mark Woolhouse, PhD, a University of Edinburgh outbreak expert. "Now this question may never be definitively answered."
Clouds of Secrecy
Secrecy clouds the beginning of the outbreak. Even the date when Chinese authorities first started searching for the origins is unclear.
The first publicly known search for the virus took place on Dec. 31, 2019, when Chinese Center for Disease Control (CDC) scientists visited the Wuhan market where many early COVID-19 cases surfaced.
However, WHO officials heard of an earlier inspection of the market on Dec. 25, 2019, according to a recording of a confidential WHO meeting provided to AP by an attendee. Such a probe has never been mentioned publicly by either Chinese authorities or WHO.
In the recording, WHO's top animal virus expert, Peter Ben Embarek, PhD, mentioned the earlier date, describing it as "an interesting detail." He told colleagues that officials were "looking at what was on sale in the market, whether all the vendors have licenses, [and] if there was any illegal [wildlife] trade happening in the market."
A colleague asked Ben Embarek, who is no longer with WHO, if that seemed unusual. He responded that "it was not routine," and that the Chinese "must have had some reason" to investigate the market. "We'll try to figure out what happened and why they did that."
Ben Embarek declined to comment. Another WHO staffer at the Geneva meeting in late January 2020 confirmed Ben Embarek's comments.
The AP could not confirm the search independently. It remains a mystery if it took place, what inspectors discovered, or whether they sampled live animals that might point to how COVID-19 emerged.
A Dec. 25, 2019, inspection would have come when Wuhan authorities were aware of the mysterious disease. The day before, a local doctor sent a sample from an to get sequenced that turned out to contain COVID-19. Chatter about the unknown pneumonia was spreading in Wuhan's medical circles, according to one doctor and a relative of another who declined to be identified, fearing repercussions.
A scientist in China when the outbreak occurred said they heard of a Dec. 25 inspection from collaborating virologists in the country. They declined to be named out of fear of retribution.
WHO said in an email that it was "not aware" of the Dec. 25 investigation. It is not included in the U.N. health agency's official .
When China CDC researchers from Beijing arrived on Jan. 1 to collect samples at the market, it had been ordered shut and was already being disinfected, destroying critical information about the virus. Gao Fu, PhD, then head of the China CDC, mentioned it to an American collaborator.
"His complaint when I met him was that all the animals were gone," said Columbia University epidemiologist Ian Lipkin, MD, PhD.
Robert Garry, PhD, who studies viruses at Tulane University, said a Dec. 25 probe would be "hugely significant," given what is known about the virus and its spread.
"Being able to swab it directly from the animal itself would be pretty convincing and nobody would be arguing" about the origins of COVID-19, he said.
But perhaps local officials simply feared for their jobs, with memories of firings after the 2003 SARS outbreak still vivid, said Ray Yip, MD, MPH, the founding head of the U.S. CDC outpost in China.
"They were trying to save their skin, hide the evidence," Yip said.
The Wuhan government did not respond to a faxed request for comment.
Another early victim was Zhang Yongzhen, the first scientist to publish a sequence of the . A day after he wrote a memo urging health authorities to take action, China's top health official ordered Zhang's lab closed.
"They used their official power against me and our colleagues," Zhang wrote in an email provided to AP by Edward Holmes, PhD, an Australian virologist.
On Jan. 20, 2020, a WHO delegation arrived in Wuhan for a 2-day mission. China did not approve a visit to the market, but they stopped by a China CDC lab to examine infection prevention and control procedures, according to an internal WHO travel report. WHO's then-China representative, Gauden Galea, MD, told colleagues in a private meeting that inquiries about COVID-19's origins went unanswered.
By then, . Among Chinese doctors and scientists, the sense grew that was hunting for someone to blame.
"There are a few cadres who have performed poorly," Chinese leader Xi Jinping said in in February. "Some dare not take responsibility, wait timidly for orders from above, and don't move without being pushed."
The government opened investigations into top health officials, according to two former and current China CDC staff, and three others familiar with the matter. Health officials were encouraged to report colleagues who mishandled the outbreak to Communist Party disciplinary bodies, according to two of the people.
Some people both inside and outside China speculated about a laboratory leak. Those suspicious included , but also researchers close to WHO.
The focus turned to the Wuhan Institute of Virology, a high-level lab that experimented with some of the world's most dangerous viruses.
In early February 2020, some of the West's leading scientists, headed by Jeremy Farrar, MD, PhD, then at Britain's Wellcome Trust, and Anthony Fauci, MD, then director of the U.S. National Institute of Allergy and Infectious Diseases at NIH, banded together to assess the origins of the virus in calls, a Slack channel, and emails.
They drafted a paper suggesting a natural evolution, but even among themselves, they could not agree on the likeliest scenario. Some were alarmed by features they thought might indicate tinkering.
"There have [been] suggestions that the virus escaped from the Wuhan lab," Holmes, the Australian virologist, who believed the virus originated in nature, wrote in a Feb. 7, 2020, email. "I do a lot of work in China, and I can [assure] you that a lot of people there believe they are being lied to."
American scientists close to researchers at the Wuhan Institute of Virology warned counterparts there to prepare.
James LeDuc, PhD, head of a Texas lab, emailed his Wuhan colleague on Feb. 9, 2020, saying he'd already been approached by U.S. officials. "Clearly addressing this will be essential, with any kind of documentation you might have," he wrote.
The Chinese government was conducting its own secret investigation into the Wuhan Institute. Gao, the then-head of the China CDC, and another Chinese health expert revealed its existence in . Both said the investigation found no evidence of wrongdoing, which Holmes, the Australian virologist, also heard from another contact in China. But Gao said , and some experts suspect they may never be released.
WHO started negotiations with China for a further visit with the virus origins in mind, but it was China's Foreign Ministry that decided the terms.
Scientists were sidelined and politicians took control. China refused a visa for Ben Embarek, then WHO's top animal virus expert. The itinerary dropped nearly all items linked to an origins search, according to draft agendas for the trip obtained by the AP. And Gao, the then-head of the China CDC who is also a respected scientist tasked with investigating the origins, was left off the schedule.
Instead, Liang Wannian, PhD, a politician in the Communist Party hierarchy, took charge of the international delegation. Liang is an epidemiologist close to top Chinese officials and China's Foreign Ministry , not science-backed policies, according to nine people familiar with the situation who declined to be identified to speak on a sensitive subject.
Liang ruled in favor of shutting the Wuhan market at the beginning of the outbreak, according to . Significantly, it was Liang who promoted an imported into China. Liang did not respond to an emailed request for comment.
Most of the WHO delegation was not allowed to go to Wuhan, which was under lockdown. The few who did learned little. They again had no access to the Wuhan Institute of Virology or the wildlife market and obtained only scant details about China CDC efforts to trace the coronavirus there.
On the train, Liang lobbied the visiting WHO scientists to praise China's health response in their public report. Bruce Aylward, MD, a senior adviser to WHO Director-General Tedros Adhanom Ghebreyesus, PhD, saw it as the "best way to meet China's need for a strong assessment of its response."
The new section was so flattering that colleagues emailed Aylward to suggest he "dial it back a bit."
"It is remarkable how much knowledge about a new virus has been gained in such a short time," read the final report, which was reviewed by China's top health official before it went to Tedros.
As criticism of China grew, the Chinese government deflected blame. Instead of firing health officials, they declared their virus response a success and closed investigations into the officials with few job losses.
"There were no real reforms, because doing reforms means admitting fault," said a public health expert in contact with Chinese health officials who asked not to be identified because of the sensitivity of the matter.
In late February 2020, the internationally respected doctor Zhong Nanshan, MD, and said that "the epidemic first appeared in China, but it did not necessarily originate in China."
Days later, Chinese leader Xi . A leaked directive from China's Publicity Department ordered media , and a public WeChat account reposted an essay claiming the U.S. military created COVID-19 at a Fort Detrick lab and spread it to China during a 2019 athletic competition in Wuhan. Days later, a Chinese Foreign Ministry spokesperson .
The false claims enraged U.S. President Donald Trump, who began publicly blaming China for the outbreak, calling COVID-19
Chinese officials told WHO that blood tests on lab workers at the Wuhan Institute of Virology were negative, suggesting they hadn't been previously infected with bat coronaviruses. But when WHO pressed for an independent audit, Chinese officials balked and demanded WHO investigate the U.S. and other countries as well.
By blaming the U.S., Beijing diverted blame. , where many Chinese were upset by racially charged criticism. But outside China, it fueled speculation of a lab-leak cover-up.
By the time WHO led in January 2021, a year into the pandemic, the atmosphere was toxic.
Liang, the Chinese health official in charge of two earlier WHO visits, continued to promote the questionable theory that the virus was shipped into China on frozen food. He suppressed information suggesting it could have come from animals at the Wuhan market, organizing market workers to tell WHO experts no live wildlife was sold and cutting recent photos of wildlife at the market from the final report. There was heavy political scrutiny, with numerous Chinese officials who weren't scientists or health officers present at meetings.
Despite a lack of direct access, the that a lab leak was "extremely unlikely." So it came as an infuriating surprise to Chinese officials when, months later, WHO chief said that it was to rule out the lab-leak theory, saying such lab accidents were "common," and pressed China to be more transparent.
China told WHO any future missions to find COVID-19 origins should be elsewhere, according to a letter obtained by AP. Since then, global cooperation on the issue has ground to a halt; an independent group convened by WHO to investigate the origins of COVID-19 in 2021 has been stymied by the lack of cooperation from China and other issues.
Chinese scientists are still under heavy pressure, according to 10 researchers and health officials. Researchers who published papers on the coronavirus ran into trouble with Chinese authorities. Others were barred from travel abroad for conferences and WHO meetings. Gao, the then-director of the China CDC, was investigated after of COVID-19 data, and again after giving interviews on the virus origins.
New evidence is treated with suspicion. In March 2023, scientists announced that genetic material collected from the market showed mixed with COVID-19 in early 2020, data that WHO said should have been publicly shared years before. The findings were posted, then removed by Chinese researchers with little explanation.
The head of the China CDC Institute of Viral Disease was forced to retire over the release of the market data, according to a former China CDC official who declined to be named to speak on a sensitive topic.
"It has to do with the origins, so they're still worried," the former official said. "If you try and get to the bottom of it, what if it turns out to be from China?"
Other scientists note that any animal from which the virus may have originally jumped has long since disappeared.
"There was a chance for China to cooperate with WHO and do some animal sampling studies that might have answered the question," said Tulane University's Garry. "The trail to find the source has now gone cold."