The World Health Organization’s Scientific Advisory Group for the Origins of Novel Pathogens (SAGO), a team of 27 independent international experts, has released its latest report on the origins of SARS-CoV-2—the virus that caused the COVID-19 pandemic.

SAGO’s work has helped deepen the understanding of how the virus may have emerged. However, the group stated in its report that much of the information needed to fully assess all possible theories about the virus's origin has still not been made available.By Sa“I thank each of the 27 members of SAGO for their time and expertise over more than three years,” said WHO Director-General Dr. Tedros Adhanom Ghebreyesus. “Right now, we must keep all possible explanations open—including transmission from animals (zoonotic spillover) and a potential lab-related incident. We continue to urge China and any other country with relevant information to share it openly, for the sake of preventing future pandemics.”

In its report, SAGO examined the main theories about how COVID-19 began. It concluded that the strongest evidence so far supports the idea that the virus likely came from animals—either directly from bats or through another animal species.

WHO has asked China to share several important pieces of information: hundreds of genetic sequences from people infected early in the outbreak, detailed data on animals sold at markets in Wuhan, and information about lab work and safety protocols in Wuhan laboratories. As of now, China has not provided this information to WHO or SAGO.

SAGO’s first report, with preliminary findings and recommendations, was published on June 9, 2022. The new report updates that work by including additional scientific studies (both published and unpublished), field investigations, interviews, audit results, and intelligence and government reports.

The group has held 52 meetings in various formats and consulted with scientists, researchers, journalists, and others.

“This is not just about science—it’s a moral and ethical responsibility,” said Dr. Marietjie Venter, Chair of SAGO and a professor at the University of the Witwatersrand in South Africa. “Understanding how SARS-CoV-2 started and spread is crucial to preventing future pandemics, saving lives, and reducing suffering.”

In late 2020, WHO Member States passed a resolution asking the organization to study how COVID-19 began. As part of that effort, a team of international and Chinese experts visited China in early 2021 and released a report in March of that year.

In July 2021, Dr. Tedros formed SAGO with two main goals:

To create a global framework for investigating new and re-emerging pathogens, which was published last year.
To use that framework to study how COVID-19 started.
The search for the true origins of the virus is ongoing. WHO welcomes any new evidence and says SAGO will continue its work and review any new information that becomes available.