Where did covid originate? Here’s what we know and what we don’t

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WASHINGTON — The Energy Department concludes, with “low confidence,” that an accidental lab leak in China most likely sparked the coronavirus pandemic’s worst public health crisis in a century — and whether the virus is at its heart was somehow connected with scientific research.

Scientists and intelligence agencies have tried their best to answer this question, but conclusive evidence is difficult to obtain. The country’s intelligence agencies are divided and none of them changed their conclusions after looking at the Energy Department’s findings, officials said.

Scientists who have studied the genetics of the virus, and the patterns by which it spread, say the most likely reason is that the virus jumped from living mammals to humans – a scientific phenomenon known as “zoonotic spillover”. Goes to Huanan Seafood Wholesale Market in Wuhan, China, the city where the first cases of COVID-19 were reported in late 2019.

But other scientists say there is evidence, though circumstantial, that the virus came from a laboratory, possibly the Wuhan Institute of Virology, which had deep expertise in researching coronaviruses. Lab accidents happen; In 2014, after accidents involving bird flu and anthrax, the Centers for Disease Control and Prevention tightened its biosecurity practices.

The debate is politically loaded. President Donald J. The lab leak theory gained popularity among Republicans in the spring of 2020 after Trump used inflammatory words to blame China for the pandemic. Many Democrats have not agreed with the lab leak hypothesis; Some say they believe in the natural causes explanation, and others say there can never be enough intelligence to draw that conclusion.

The Energy Department’s findings have provided a boost to House Republicans, who are investigating the origins of the pandemic. But politics aside, experts say understanding the cause of the public health crisis that has killed nearly seven million people could help researchers understand how to prevent the next one.

Here’s what we do and don’t know about the origins of the coronavirus.

Tracing the origin of a virus is often difficult, but China has compounded that problem by making it very difficult to gather evidence.

By the time Chinese researchers arrived to collect samples from the Huanan market, police had sealed off and disinfected the market after several people associated with it had become ill with what would later be identified as Covid. No live market animal was released.

Some scientists also believe that China provided an incomplete picture of early Covid cases. And they worry that the directive to hospitals to report specifically market-linked illnesses early in the outbreak may have led doctors to ignore other cases, creating a biased snapshot of the spread.

Experts have tried to work around holes in the data.

Scientists have examined cases of hospitalized patients before calling on doctors to seek market linkages. They have also mapped the locations of early Covid cases in Wuhan – including both people who were initially linked to the market and those who were not – and found what they say are signs that the virus may have started to spread in the market. It is done.

Some of those same scientists have also studied maps of where investigators found the virus in the Huanan market, including walls, floors and other surfaces, and found that those samples clustered in an area of ​​the market where live animals were sold.

And some scientists have said that separate genetic analyzes of the early stages of the pandemic suggest that the virus spread among people working or shopping at the market on two separate occasions.

Other scientists have disputed that such studies can indicate the origin of the market with much confidence. For example, they have said that evidence of two separate spillovers in the market may also be evidence of the virus evolving as it spreads from person to person.


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Some have also argued that as much attention is being paid to the Wuhan Institute of Virology, not enough is paid to a separate research site in the city, the Wuhan Center for Disease Control and Prevention. The center is very close to Hunan market.

In October, Republicans on the Senate Health Committee published an analysis of the pandemic’s origins arguing that it was “most likely the result of an incident not related to the research,” while acknowledging that the findings “need to be conclusive.” Wasn’t the intention.”

The report highlighted what its authors described as “persistent biosafety problems” at the Wuhan Institute of Virology, along with holes in the natural origin theory. The report, however, relied largely on existing public evidence rather than new or classified information, and did not provide evidence to show that the Wuhan Institute stored in its archives any virus that may have caused COVID-19. The doer can be a virus, with or without scientific manipulation.

The lab leak hypothesis is bolstered, the report said, by the absence of any published evidence that SARS-CoV-2, the virus that causes Covid-19, was circulating in animals before the pandemic. Virus samples collected on refrigerators, countertops and other surfaces in the Huanan market were genetically identical to human samples, suggesting the virus was shed by humans, not animals, it said.

But some experts said the inability to find an infected animal proved nothing, as China closed the market and killed all its animals before testing.

In 2018, before the pandemic, the Wuhan Institute and its partners – including the EcoHealth Alliance, a research group whose work is funded by the United States – sought funding from the Department of Defense to conduct experiments on coronaviruses with new symptoms. That would make them highly contagious. In humans

The group project was never funded. But the report points to that proposition, noting that the virus that causes Covid-19 has the same characteristics researchers were looking for. This has convinced some scientists that a leak is possible in the laboratory. The Senate Republican report speculated that the virus may have escaped — perhaps by infecting a researcher who took it outside the lab.

The National Institutes of Health paid for some of the EcoHealth Alliance’s work in Wuhan, but NIH officials have repeatedly said the virus being studied with US taxpayer dollars bears no genetic resemblance to the virus that causes Covid-19. Do not keep But NIH Acting Director Dr. Lawrence A. Tabak recently admitted during a Congressional hearing that he did not know what else the Wuhan Institute was working on.

In May 2021, several months after taking office, President Biden ordered the nation’s intelligence agencies to conduct a 90-day investigation into the cause of the pandemic. The findings of that review were released in August 2021 and confirmed what the agencies had previously said: both the natural origin theory and the lab leak theory were plausible.

In a statement at the time, Mr. Biden called on China to be more transparent about what caused the virus to emerge there in late 2019.

The Department of Energy’s new findings are based on intelligence that isn’t publicly available, so it’s hard to know what’s responsible for the change. But the department’s use of the phrase “low confidence” indicates that its level of certainty is not high. The FBI, however, concluded with “moderate confidence” that the virus accidentally emerged from a laboratory.

Four other intelligence agencies and the National Intelligence Council have concluded with less confidence that the virus most likely emerged through natural transmission. The CIA, the country’s pre-eminent spy agency, has taken no position and remains undecided.

House Republicans are trying to investigate the origins of the pandemic and collect evidence that could shed light on its cause — including whether China hid facts about the initial outbreak and whether US tax dollars funded Wuhan. What research could have been done.

Now that Republicans are in charge of the House, investigative work is increasing on several committees, including the Intelligence Committee, the Energy and Commerce Committee and the subcommittee on the coronavirus pandemic. A spokesman said the subcommittee would hold its first hearing on the substantive question on March 8.

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