THE virus which causes Covid-19 is “extremely unlikely” to have entered the human population as a result of a laboratory-related incident, global health leaders have said.

China has faced claims that the Wuhan Institute of Virology could be the suspected source of the Covid-19 virus.

Sars-CoV-2 “may have originated from zoonotic transmission”, meaning it passed from animals to humans, a team of experts from China and the World Health Organisation (WHO) concluded.

Experts said the early findings indicate that the virus was introduced to humans through an “intermediary host”, which means it jumps from one species to another, and then jumps from the second species to humans.

But the “reservoir hosts” – the animals in which the virus originated – remain to be identified, they told a press conference.

The first probable case of the virus investigated by the team was on December 8, 2019. This case did not have any links to the animal market which was initially thought to be where the virus “spillover” from animals to humans occurred.

Dr Peter Ben Embarek, leader of the WHO team investigating the origins of the virus in Wuhan, said: “The findings suggest lab incident hypothesis is extremely unlikely to explain the introduction of the virus into the human population.”

Meanwhile, there is no evidence that the virus was present in Wuhan before December 2019, they said. The experts added that they “don’t know” the exact role of Wuhan’s Huanan Seafood Wholesale Market in the origin of the virus.

A cluster of cases was linked to the market, but officials also found cases among people who had no ties to the market.

Some had links to other markets and others had no links to markets at all, they said.

He added: “We don’t know the exact role of the Huanan market ... How it was introduced and spread within the market is still unknown.”