A joint report into the origins of COVID by the World Health Organization (WHO) and China has found it is "extremely unlikely" that the virus escaped from a lab, according to a draft version seen by AP News.
The leaked report comes after weeks of investigations by the WHO team, which arrived in the Chinese city of Wuhan in January.
The draft report, which may still be changed ahead of its official release, was provided to AP on Monday by a Geneva-based diplomat who wanted to remain anonymous. It is expected to be released publicly in the coming days following multiple delays. The report states the most likely way in which COVID began spreading between humans was via animals. It said it was likely that there could have been a direct spread from bats to humans, but even more likely that some secondary animal took the virus from bats to humans.
The closest relative of the COVID virus has been found in bats, but other animals such as mink and cats are also susceptible which could make them carriers.
It also stated there was a possibility humans could have caught the virus when it was already present in cold-chain food products, but added this was not likely.
The report could not confirm whether or not the global COVID outbreak started at the Huanan seafood market in Wuhan, where some of the earliest groups of cases were first detected.
Many scientists have cast doubt on the idea that COVID originated in a lab, but Robert Redfield, former director of the Centers for Disease Control and Prevention (CDC), has supported the idea.
Redfield told CNN on March 26: "I am of the point of view that I still think the most likely etiology [cause] of this pathogen in Wuhan was from a laboratory—escaped.
"That's not implying any intentionality. It's my opinion. But I am a virologist, I have spent my life in virology. I do not believe this somehow came from a bat to a human, and at that moment in time the virus that came to the human became one of the most infectious viruses that we know in humanity for human to human transmission.
"Normally when a pathogen goes from a zoonote [sic] to a human, it takes a while for it to figure out how to become more and more efficient in human to human transmission. I just don't think this makes biological sense."
Paul Duprex, a virologist and director of the center for vaccine research at the University of Pittsburgh, criticized Redfield's stance and said he has seen no evidence to support it. He told USA Today: "There's a fundamental difference between having a theory and testing a theory and showing evidence that your theory is a fact."