WHO Panel Reaffirms All COVID-19 Origin Theories Open as Evidence Gaps Remain

After more than three years of intensive investigation, the World Health Organization’s (WHO) Scientific Advisory Group for the Origins of Novel Pathogens (SAGO) has released its long-anticipated report on the origins of SARS-CoV-2, the virus responsible for the COVID-19 pandemic. Despite some progress in understanding potential transmission pathways, the panel of 27 independent global experts concluded that crucial data remains missing, and all origin hypotheses—ranging from zoonotic spillover to a laboratory incident—remain scientifically plausible.

Findings of the Final Report

The SAGO report consolidates findings from peer-reviewed research, field investigations, government and intelligence reports, interviews, and briefings. Central to the report’s conclusions is the observation that the “weight of available evidence… suggests zoonotic spillover,” most likely through direct contact with bats or via an intermediate animal host. However, the lack of essential data has prevented the committee from eliminating any possible theory, including the possibility of a laboratory-associated origin.

This conclusion echoes the group’s earlier interim findings published in June 2022 and updates the evaluation with new, though still incomplete, evidence. It is the result of 52 formal meetings, continuous expert deliberations, and engagements with external stakeholders, including scientists, journalists, and public health institutions.

WHO Leadership Reiterates Call for Transparency

In releasing the report, WHO Director-General Dr. Tedros Adhanom Ghebreyesus expressed his gratitude to the SAGO members for their dedication and scientific rigour.

“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,” Dr. Tedros stated. “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.”

Despite repeated requests from WHO and SAGO, China has yet to provide several key datasets that could help resolve the origins question. These include:

• Hundreds of genetic sequences from COVID-19 patients in the early stages of the outbreak

• Detailed records of animals sold in Wuhan’s markets before and during the outbreak

• Comprehensive information on biosafety protocols and research activities conducted in Wuhan-based laboratories

A Global Effort Rooted in Scientific and Moral Responsibility

Dr. Marietjie Venter, Chair of SAGO and Distinguished Professor at the University of the Witwatersrand in South Africa, emphasized that the effort to trace the virus's origins transcends scientific inquiry alone.

“As the report says, this is not solely a scientific endeavour, it is a moral and ethical imperative,” Dr. Venter said. “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.”

She emphasized that while the road to scientific certainty is long and often marked by geopolitical complexity, understanding the biological, social, and environmental contexts of pandemics is essential for future global health preparedness.

From Joint Investigations to SAGO Formation

The origins investigation began in earnest following a resolution by WHO Member States during a Special Session of the World Health Assembly in late 2020. In early 2021, a joint mission of Chinese and international experts visited China and released its report in March 2021, categorizing zoonotic spillover as “likely to very likely” and lab-related origin as “extremely unlikely”—a conclusion met with international scrutiny due to limited data access.

In July 2021, Dr. Tedros launched SAGO with a dual mandate:

1. To develop a standardized global framework for studying the origins of emerging and re-emerging pathogens.

2. To apply that framework to the case of SARS-CoV-2.

The framework, published in 2024, is already influencing broader efforts to trace the emergence of other pathogens such as MERS, Ebola, and H5N1 avian influenza.

An Unfinished Scientific Journey

Despite years of investigation, SAGO’s work confirms that the origins of SARS-CoV-2 remain scientifically unresolved. Without full cooperation from all relevant nations and institutions—especially those with access to primary data from the early stages of the outbreak—the global community may never arrive at a conclusive answer.

Nevertheless, the SAGO report is clear: the pursuit of answers must continue. WHO and SAGO remain open to reviewing and incorporating any new credible information that surfaces, no matter its source. The panel has reaffirmed its commitment to updating the global community as more data becomes available.

Lessons for the Future

The SAGO process highlights the complex interplay between science, politics, and public trust. It also underscores the importance of global transparency, the free exchange of data, and the creation of robust surveillance systems to prevent and respond to future pandemics.

The WHO has used the SAGO experience to advocate for stronger international agreements on pathogen sharing and biosafety standards. As the world faces increasing threats from climate-linked zoonoses and rapid urbanization, understanding the origin of one pandemic may be key to preventing the next.