It is “extremely unlikely” the novel coronavirus came from a laboratory incident in China, according to a joint mission investigating the origins of the pandemic.
Investigators believe the most likely cause of the initial outbreak was the virus jumping from an “intermediary host species” to humans.
An international team of World Health Organisation scientists, working with experts in China, have been researching how the COVID-19 pandemic began.
The team has visited key locations in Wuhan, where the first cases were reported, and spoken to patients, first responders and Chinese scientists.
Evidence so far suggests the novel coronavirus may have jumped from animals to humans, but the team told a news conference it is not yet sure exactly which animals it came from or where this occurred.
Scientists also revealed the novel coronavirus could have been circulating in regions outside Wuhan before the first reported cases of the outbreak.
Unpublished data suggests samples of SARS-CoV-2 were found several weeks before the first reported cases in Wuhan, the head of China’s National Health Commission’s expert panel of COVID-19 response Liang Wannian said.
However, he said there was no evidence that COVID was spreading in Wuhan before December 2019, when the first cases were reported, after officials looked at research samples, pharmaceutical sales and hospital records.
There was also no evidence of “large outbreaks” before December 2019 in Wuhan or elsewhere, according to a World Health Organisation spokesperson.