The World Health Organization recommends that more investigations be done into the theory that Covid-19 was leaked from a Chinese lab. Although initially dismissed as a conspiracy theory, some experts and officials have taken it seriously.

The WHO has made a U-turn. It was heavily criticised last year for saying that it was “extremely unlikely that” the virus had leaked from an lab. They have also been accused of being too trusting and deferential towards China.

Beijing responded to the report on Friday and suggested, without supporting evidence, that the virus could have originated in an American laboratory.

A spokesperson for the Foreign Ministry Zhao Lijian stated that the lab leak theory was a fabrication by anti-China forces to achieve political ends. This has nothing to do science. We have always supported and actively participated in science-based global viruses tracing. However, we strongly oppose any form of political manipulation.

He called for investigations into “highly suspect laboratories such as Fort Detrick in Maryland” and the University of North Carolina, where China suggested, again without evidence that the U.S. was creating the coronavirus bioweapon. NBC News reached out to the Department of Defense as well as the University of North Carolina in order to get a response.

Thursday’s first report of the Scientific Advisory Group for the Origins of Novel Pathogens (also known as SAGO) reflected the WHO’s shift in direction.

Because of the links that many patients had to Wuhan’s seafood market in December 2019, the SAGO said the market played an “important role” in the outbreak.

It said that there were still gaps in our knowledge, including how the virus reached the market and where it spread to humans.

The report suggested “further investigation” into the possibility that this could have occurred in a laboratory, and “all other” possible routes.

China suggested previously that Covid might have been brought into its country as frozen food. The WHO report on Thursday suggested that the cold chain theory should also be explored.

NBC News attempted to reach China’s Information Office for the National Heath Commission Friday for comment, but was informed that the officials were gone for the day.

Once, a lab leak was viewed as fringe conspiracy theory. It was clouded by the false belief that its supporters believed that Covid-19 had been deliberately released to be a bio-weapon. Many of its supporters believed that the virus might have escaped from a laboratory, namely the Wuhan Institute of Virology. This was based on an accident during virus testing. This was confirmed by Thursday’s report.

In 2012, President Joe Biden ordered U.S. spy agencies that they compile a report on Covid’s possible origins. The report stated that at least one American intelligence agency believed it could have escaped from the lab, but the community is still divided.

Jean-Claude Manuguerra (co-chair) of the 27-member international SAGO said that some scientists may be allergic to the idea, but urged them not to be too rigid, The Associated Press reported.

The report stated that three of the members of the group disagreed with the idea that the laboratory-leak theory should not be investigated. These were Professor Yun-Gui Yang from China and Dr. Vladimir Dedkov from Russia.

The WHO has made a significant shift with Thursday’s report. In a February 2021 report, they said that it was “extremely unlikely”. After months of criticism and pressure from outsiders, Tedros Adhanom Ghebreyesus, Director General, admitted that it was premature to rule out the idea in July. “I have worked at the laboratory, and accidents happen.”

Tedros was accused in the beginning of Covid-19 of being too eager for President Xi Jinping to be pleased. China increased its funding for the WHO by $30 million in 2020, just as President Donald Trump pulled out completely from it.

China also took too long to provide data and warn the world about the potential dangers of the virus’ rapid spread.

Recent events have seen the Sino-WHO relationship take a major blow, with Beijing censoring Tedros for criticizing its “zero-Covid” policy.

Jamie Metzl is a member of a WHO advisory panel that is not related to the SAGO. He told the AP that the Chinese government was still refusing to share vital raw data and would not permit the required, thorough audit of the Wuhan laboratories.