Tedros Adhanom Ghebreyesus, director-general of the World Health Organisation (WHO), says there will be further investigation into the origin of COVID-19 and its transmission to humans.
He stated this at a briefing of member states on Thursday, following the release of the report by the WHO team which visited China to investigate the origin of the virus.
An international team of experts, which travelled to China in January, had said after an investigation that it was “extremely unlikely” that the virus emanated from a Chinese laboratory.
Commenting on the team’s investigation, Ghebreyesus said the theory that the virus originated in a laboratory in Wuhan, China, cannot be completely ruled out yet.
He expressed readiness to deploy another team of scientists to carry out more research.
“The team reports that the first detected case had symptom onset on the 8th of December 2019. But to understand the earliest cases, scientists would benefit from full access to data including biological samples from at least September 2019,” he said.
“In my discussions with the team, they expressed the difficulties they encountered in accessing raw data. I expect future collaborative studies to include more timely and comprehensive data sharing.
“I welcome the recommendations for further studies to understand the earliest human cases and clusters, to trace the animals sold at markets in and around Wuhan, and to better understand the range of potential animal hosts and intermediaries. The role of animal markets is still unclear.
“The team has confirmed that there was widespread contamination with SARS-CoV-2 in the Huanan market in Wuhan, but could not determine the source of this contamination. Again, I welcome the recommendations for further research, including a full analysis of the trade in animals and products in markets across Wuhan, particularly those linked to early human cases.
“I concur with the team’s conclusion that farmers, suppliers and their contacts will need to be interviewed. The team also addressed the possibility that the virus was introduced to humans through the food chain. Further study will be important to identify what role farmed wild animals may have played in introducing the virus to markets in Wuhan and beyond.
“The team also visited several laboratories in Wuhan and considered the possibility that the virus entered the human population as a result of a laboratory incident. However, I do not believe that this assessment was extensive enough. Further data and studies will be needed to reach more robust conclusions.
“Although the team has concluded that a laboratory leak is the least likely hypothesis, this requires further investigation, potentially with additional missions involving specialist experts, which I am ready to deploy.”
He commended China and other stakeholders for their cooperation, and added that the WHO will embark on further field visits to determine the origin of the virus.