London - A virus closely related to Covid-19 was found seven years ago in an abandoned Chinese mine, it has emerged.
Scientists in Wuhan launched an investigation when six men were struck down with fevers, coughs and pneumonia after working in the mine in 2012 to clear bat droppings.
Three of the men died and four later tested positive for coronavirus antibodies, after samples of the virus were sent to a laboratory in Wuhan the next year. The revelation is one of the most significant developments in tracing the origin of the disease, thought to have started in the city in eastern China last year.
It comes as former British spy chief Sir Richard Dearlove called for an "open debate" about Covid’s origins. He said: "I subscribe to the theory… that it’s an engineered escapee from the Wuhan Institute.
"I am not saying anything other than it was the result of an accident and that the virus is the consequence of gain-of-function experiments that were being conducted in Wuhan, which I don’t think are particularly sinister.
"But there is an accumulation of evidence that this is something that has to be openly discussed in the scientific community."
The copper mine in the southwest Yunnan province where the three men died in 2012 was populated by bats, shrews and rats. It was in animal droppings the virus was found, the Sunday Times reported.
The infection of the men, scientifically pinpointed the next year, was considered a "new strain" at the time. It means the first case closely linked to Covid was a 45-year-old man with the surname of Guo on April 24, 2012.