P4 lab (center) on the Wuhan Institute of Virology campus in Wuhan, central China's Hubei province, on May 13, 2020.


P4 lab (center) on the Wuhan Institute of Virology campus in Wuhan, central China’s Hubei province, on May 13, 2020.
Photo: Hector Retamal / AFP (Getty Images)


Scientists brought together by the World Health Organization to investigate the origin of the covid-19 outbreak announced their early findings. They concluded that the first known cases followed in a seafood market in Wuhan, China, in December 2019 likely did not represent the original source of the outbreak. They also considered the probability of a lab accident causing the pandemic to be “extremely low” and predicted that the virus did not circulate locally in humans long before the first cases were discovered.

The international team of scientists began their research in mid-January 2021 and traveled to various parts of China, including the Huanan Seafood Market in Wuhan, a study in which the first cases of pneumonia, then mysterious, were reported in late December 2019. Mission with local scientists from China, as part of an agreement with the Chinese government to enter the country. At a press conference held in Wuhan on Tuesday, scientists revealed what they have learned so far.

The team’s results are not final, and criticism of China’s handling of the pandemic will undoubtedly continue, especially in the early stages. Activists and local journalists accused The Chinese government is trying to silence scientists and the public who tried to warn about the covid-19 threat when it was first discovered. And it took the country about a month to acknowledge that the virus could actually spread from person to person.

Even recently AP reported In December, as China tried to limit the efforts of scientists to investigate the origin of the outbreak, some officials supported unfounded theories that the virus originated elsewhere in the world. However, AP’s reported WHO scientists were given as many access as they wanted during this investigation.

The team said, among other things, they found a lot of evidence that the Huanan cases were not the first cases of covid-19 in humans. One key finding, according to Liang Wannian, China’s chief scientist on the mission, was the signs of diversity in the coronavirus (formally called SARS-CoV-2) samples taken from these cases. This probably means that the Huanan cluster is not the original transmission event.

The team also analyzed hospital surveillance data from Wuhan and the surrounding Hubei province and found no unusual increases in flu-like illnesses before December 2019. This suggests that Wannian was “not a significantly unrecognized circulation. SARS-CoV-2 in Wuhan in the second half of 2019.” It should be noted that this finding contradicts other evidence. China and other countries proposition the virus may have made people sick in November 2019 or earlier.

Another part of the research involved visiting the Wuhan Institute of Virology, which was chosen by some as the possible source of a lab accident that somehow released the coronavirus to the community (some even claimed that the virus was deliberately created and distributed). There is no conclusive evidence for this theory appeared until today studies He found no indication that the coronavirus was artificially made in the laboratory. The WHO team concluded that the laboratory leak theory was impossible enough to effectively cover the book.

“The findings show that the laboratory event hypothesis is highly unlikely to explain the virus’s entry into the human population,” said Peter Ben Embarek, leader of the WHO mission and an expert on infectious disease and food safety, in the press. conference.

Embarek said the most likely probability for the origin of the pandemic is that the coronavirus spreads from bats to an intermediate host (possibly pangolins) and from there to humans. Another possibility that is still under investigation is that the virus could be transmitted to humans through frozen food products. evidence He claimed that he could live for a short time in these conditions. However, the researchers did not go into detail as to how this path might have occurred. And WHO scientists still do not rule out the possibility of infecting humans by bats alone.