By Bunmi Yekini
The World Health Organization’s (WHO) Scientific Advisory Group for the Origins of Novel Pathogens (SAGO) has released its final report on the origins of SARS-CoV-2, the virus responsible for the COVID-19 pandemic, reaffirming the theory of a zoonotic spillover while stressing that all possible hypotheses—including a laboratory-related incident—remain on the table due to gaps in crucial data.
The 27-member international panel of scientists worked for over three years, analyzing peer-reviewed research, field data, intelligence reports, and interviews. Their findings, released today, conclude that “the weight of available evidence… suggests zoonotic spillover… either directly from bats or through an intermediate host.”
However, the panel noted that significant information needed to fully evaluate all hypotheses has not been provided, particularly from China.
“I thank each of the 27 members of SAGO for dedicating their time and expertise to this very important scientific undertaking over more than three years,” said Dr Tedros Adhanom Ghebreyesus, WHO Director-General. “As things stand, all hypotheses must remain on the table, including zoonotic spillover and lab leak. We continue to appeal to China and any other country that has information about the origins of COVID-19 to share that information openly, in the interests of protecting the world from future pandemics.”
The report emphasizes that WHO had requested access to hundreds of genetic sequences from early COVID-19 patients, data on animals sold at Wuhan markets, and records on laboratory conditions in the city, but China has yet to share these materials.
“As the report says, this is not solely a scientific endeavour, it is a moral and ethical imperative,” said Dr Marietjie Venter, Chair of SAGO and Distinguished Professor at the University of the Witwatersrand, South Africa. “Understanding the origins of SARS-CoV-2 and how it sparked a pandemic is needed to help prevent future pandemics, save lives and livelihoods, and reduce global suffering.”
SAGO’s work stems from a 2020 World Health Assembly resolution that tasked WHO with investigating the virus’s origins. An earlier joint WHO-China mission in early 2021 led to an initial report. SAGO, established in July 2021, had a dual mandate: to create a global framework for investigating emerging pathogens and to apply that framework to COVID-19’s origins.
Despite 52 convenings, multiple briefings with scientists, and access to some data, the report underscores that the investigation is still incomplete. WHO and SAGO say they are ready to evaluate any new evidence should it become available.
“The work to understand the origins of SARS-CoV-2 remains unfinished,” said the WHO in a statement. “We welcome any further evidence and reaffirm our commitment to transparency and scientific rigor in the search for answers.”