WHO food safety and animal diseases expert Peter Ben Embarek made the assessment at the end of a visit to the central Chinese city of Wuhan, where a team of scientists is investigating the possible origins of the coronavirus. The first cases were discovered in the city in December 2019.
The Wuhan Institute of Virology has collected extensive virus samples, leading to allegations that it may have caused the original outbreak by leaking the virus into the surrounding community. China has strongly rejected that possibility and has promoted other theories that the virus may have originated elsewhere. The team is considering several theories for how the disease first ended up in humans.
“Our initial findings suggest that the introduction through an intermediary host species is the most likely pathway and one that will require more studies and more specific, targeted research,” Embarek said.
“However, the findings suggest that the laboratory incidents hypothesis is extremely unlikely to explain the introduction of the virus to the human population,” Embarek said.
Transmission through the trade in frozen products was also a likely possibility, Embarek said.
Along with the institute, the WHO team that includes experts from 10 nations has visited hospitals, research institutes, a traditional market tied to the outbreak and other sites on their visit.
The visit by the WHO team took months to negotiate after China only agreed to it amid massive international pressure at the World Health Assembly meeting last May, and Beijing has continued to deny calls for a strictly independent investigation.
Chinese authorities have kept a tight hold on information about the possible causes of the pandemic that has now sickened more than 105 million people and killed more than 2.2 million worldwide.