With Mission to China, W.H.O. Tries to Rehabilitate Its Image

A team of World Health Organization scientists said on Tuesday in China that the coronavirus probably first spread to humans through an intermediate animal host and was “extremely unlikely” the result of a lab accident.

The findings, delivered after 12 days of field work by the team visiting Wuhan, China, were the first step in what will most likely be a painstaking process to trace the origins of the global pandemic, a question that is critical to helping prevent a recurrence.

“All the work that has been done on the virus and trying to identify its origin continue to point toward a natural reservoir,” said Dr. Peter K. Ben Embarek, a food safety scientist with the W.H.O., who is leading the team of experts, speaking at a news conference in Wuhan, the city where the coronavirus was first discovered late in 2019.

Dr. Embarek dismissed the idea that the virus might have emerged from a laboratory in Wuhan, a theory that has gained currency among some officials and experts in the United States and elsewhere. “It was very unlikely that anything could escape from such a place,” he said, citing safety protocols.

The W.H.O. experts largely focused their comments on