In an effort to bolster global health security and improve the response to infectious disease outbreaks, the World Health Organization (WHO) has introduced a comprehensive global framework designed to investigate the origins of new and re-emerging pathogens. Developed in collaboration with the Scientific Advisory Group for the Origins of Novel Pathogens (SAGO), this new framework aims to fill critical gaps in the understanding of pathogen emergence, providing a structured and unified approach for scientific investigations.
While various tools and methods exist for investigating infectious disease outbreaks, this marks the first time a unified approach has been established for uncovering the origins of a novel pathogen. The framework offers a “how-to” guide, detailing the necessary investigations and scientific studies required to trace the emergence of pathogens, with updates planned based on user feedback and evolving needs.
Growing Threat of Emerging Pathogens
As recent outbreaks and pandemics have demonstrated, both human and animal health face increasing threats from known pathogens such as Ebola, Nipah, avian influenza, Lassa, and Monkeypox viruses, as well as novel pathogens like MERS-CoV, SARS-CoV-1, and SARS-CoV-2. Given the rising frequency of zoonotic spillovers—where pathogens jump from animals to humans—the ability to swiftly contain outbreaks and trace their origins has become more critical than ever. Such actions are not only essential for scientific understanding but also a moral and financial imperative in preventing global health crises.
Key Elements of the Global Framework
The WHO’s global framework outlines six key technical elements necessary for investigating pathogen origins. These studies and investigations are aimed at identifying how pathogens emerge, how they are transmitted, and how outbreaks can be prevented in the future. The six elements include:
- Early Investigations: This involves identifying potential sources of exposure and collecting samples at the source of the outbreak to understand the novel pathogen’s characteristics and establish diagnostic assays.
- Human Studies: These studies aim to understand the epidemiology of the pathogen, its clinical presentation, transmission modes, and earliest detection in syndromic surveillance samples.
- Human/Animal Interface Studies: These investigations focus on identifying potential animal reservoirs, intermediate hosts, and reverse zoonoses (pathogens transmitted from humans to animals).
- Environmental and Vector Studies: These studies examine insect vectors or other environmental sources of infection to trace the pathogen’s earliest presence in the environment.
- Genomics and Phylogenetics Studies: The framework emphasizes the importance of genomic sequencing to identify precursor strains, trace the pathogen’s evolution, and map its spatial distribution over time.
- Biosafety and Biosecurity Studies: These studies investigate whether breaches in laboratory or research activities may have contributed to the pathogen’s emergence.
Strengthening Global Health Preparedness
The WHO’s global framework serves as a valuable resource for scientists, public health officials, and investigators worldwide. It provides detailed guidance on when and how to initiate multi-disciplinary investigations and offers recommendations on the tools and capacities needed to carry them out effectively. Key elements of this guidance include establishing strong human, animal, and environmental surveillance systems, enforcing biosafety and biosecurity regulations, and ensuring laboratory expertise in testing and sequencing.
Importantly, the framework underscores the need for countries to share their findings rapidly and transparently, enabling timely implementation of measures to halt transmission and prevent further pathogen spillover events. This approach aligns with the International Health Regulations (IHR) and advocates for a One Health approach, which integrates human, animal, and environmental health to combat infectious diseases more effectively.
The Importance of Timely and Transparent Investigations
Timely investigations into the origins of pathogens are crucial not only for containing outbreaks but also for understanding how to prevent future pandemics. By identifying how and why pathogens emerge, public health authorities can take proactive measures to stop outbreaks before they begin and reduce the risk of pathogen spillover from animals to humans. Additionally, these investigations can help confirm or rule out the possibility of laboratory biosafety breaches, which have been a point of contention in some past outbreaks.
Dr. Tedros Adhanom Ghebreyesus, Director-General of the WHO, emphasized the importance of this global framework, stating, “Understanding when, where, how, and why epidemics and pandemics begin is both a scientific and moral imperative. This framework provides comprehensive guidance on the studies needed to investigate the origins of emerging pathogens. Had it been in place during COVID-19, the quest to understand its origins may have been less contentious and more successful.”
Dr. Tedros also reiterated WHO’s call for China to share all available information on the origins of COVID-19 to allow for thorough investigations of all hypotheses.
A Collaborative Global Effort
Established in November 2021, SAGO comprises independent experts from around the world tasked with identifying the best scientific approaches to understanding pathogen origins. The group plays a key role in developing this global framework, which is part of WHO’s broader efforts to strengthen health emergency preparedness and prevention systems in collaboration with Member States and global health partners.
By implementing this framework, the WHO hopes to improve the global capacity to understand, prevent, and mitigate future pandemics. Sharing findings from these investigations swiftly and transparently will enable the world to act more decisively in controlling the spread of infectious diseases and protecting both human and animal health.Top of FormBottom of Form
