Editorial: The 2025 World Health Assembly Pandemic Agreement and the 2024 Amendments to the International Health Regulations Combine for Pandemic Preparedness and Response

In 2023, the World Health Organization (WHO) identified climate change as the greatest threat to human health, recognizing its impact on vector-borne infections, changing patterns of transmission and virulence of endemic pathogens, and the risks of emerging pathogens and pandemics [1]. The global inequalities in controlling the impact on human health, including the increase in vector-borne diseases at individual and population levels have been recognized, as has the need for pandemic preparedness [2,3]. In 2025, news about national and global cuts to healthcare funding, clinical trials, and vaccine research has eroded confidence in collaborative global health security [4].

The importance of pandemic preparedness is highlighted by two recent and important findings in the US. First, the increasing number of measles outbreaks in children and adults have resulted from large numbers of unvaccinated individuals being exposed to a highly transmissible virus [5,6]. These factors have resulted in recent health alerts for individuals attending mass gatherings, including outdoor festivals, this summer [6,7]. Since late 2022, the spread of influenza A(H5N1) viruses has been observed between species, including from birds and mammals to humans, due to mutations associated with increased transmissibility [8,9]. However, in May 2025, Brock and colleagues utilized an established ferret model to demonstrate the airborne release of A/Michigan/90/2024, an H5N1 isolate from a dairy farm worker in Michigan [10]. Air sampling was able to detect transmissible airborne H5N1 virus [10]. The extent of airborne transmission of H5N1 is currently unclear. However, if the H5N1 virus follows the same evolutionary pathway in transmission to humans as was observed with SARS-CoV-2, the next viral pandemic following COVID-19 could be H5N1 avian influenza (bird flu) [9,10]. These findings underscore the importance of ongoing surveillance of emerging H5N1 strains, particularly those associated with livestock exposure, as well as the need for pandemic preparedness and early prevention measures.

On June 1, 2024, the 77th World Health Assembly of the WHO reached a consensus on amendments to the 2005 International Health Regulations, following nearly two decades of implementation and lessons learned from the COVID-19 pandemic [11,12]. The 2024 amended International Health Regulations have been identified as representing a new universal legal framework for global health, pandemic preparedness, and response and will enter into force in September 2025. [11,13]. The key amendments to the International Health Regulations include equity, financing, and implementation of pandemic preparedness and response [11,13]. The International Health Regulations were first adopted by the World Health Assembly in 1951 and have remained the only international legal framework for the prevention and control of the global spread of infectious diseases [14,15]. Revisions to the International Health Regulations were driven following the COVID-19 pandemic with the realization that domestic and global improvements were required to prevent, detect, and respond to pandemics in a timely and effective manner [13,16]. In the years leading up to the 2024 International Health Regulations amendments, it became clear that what was required was a shift from a technical and operational tool to a regulatory and political document, prioritizing equity in pandemic prevention and response while retaining and making minor changes to some fundamental recommendations [11,13]. For example, through amendments to Articles 1 and 12, the Director-General of the WHO may now declare a pandemic emergency or an acute public health emergency of international concern (PHEIC) in the event of a communicable disease [11,13].

Other amendments in the 2024 International Health Regulations aim to strengthen implementation at multiple levels of governance, and a related advisory subcommittee has been established under Article 54 of the 2024 International Health Regulations [11,13]. The most significant changes include the insertion of equity provisions, primarily imposed on the WHO [11,13]. For example, a revised Article 13 now requires the WHO Secretariat to facilitate access to health products during a Public Health Emergency of International Concern (PHEIC) or pandemic emergency [11,13]. A revised Article 44 now establishes a commitment to facilitate sustainable financing for the benefit of developing countries, with a new coordinating financial mechanism under the authority of the WHO Health Assembly [11,13]. The 2024 amendments are likely to have significant implications for the future of global health law and pandemic preparedness, as they will shape the conditions required to achieve global health equity by stimulating investment in R&D, setting priorities, mobilizing resources, and monitoring and enforcing standards [14,15]. Therefore, the 2024 amendments to the International Health Regulations represent a significant shift toward integrating political and legal considerations into the International Health Regulations framework, ensuring that they continue to be a cornerstone of international public health cooperation and progress [11,13,16]. However, the practical value of the 2024 amended International Health Regulations remains to be determined, and its effectiveness will be evaluated in conjunction with the implementation of the 2025 WHO Pandemic Agreement [17,18].

On May 20, 2025, the 78th World Health Assembly of the WHO adopted the Pandemic Agreement [17]. In a plenary session of the World Health Assembly, chaired by Dr. Tedros Adhanom Ghebreyesus, WHO Director-General, 124 governments adopted the WHO Pandemic Agreement and its 35 Articles [17,18]. The 2025 WHO Pandemic Agreement was developed following three years of negotiations that identified gaps and inequities in the global response to the COVID-19 pandemic [17]. The WHO Pandemic Agreement is an international legal agreement negotiated under Article 19 of the WHO Constitution and is the second such legal agreement, following the WHO Framework Convention on Tobacco Control, which was adopted in 2003 and entered into force in 2005 [17,18]. The Pandemic Agreement aims to enhance international collaboration to ensure a more effective and more equitable response to future pandemics, guided by the World Health Organization (WHO) [17]. The Pandemic Agreement follows the 2024 amendments to the International Health Regulations [11,13].

The WHO Pandemic Agreement document outlines the principles, approaches, and tools to enhance international coordination for pandemic prevention, preparedness, and response, including equitable and timely access to vaccines, diagnostics, and therapeutics [17]. The WHO Member States have also directed the IGWG to initiate steps to enable the establishment of the Coordinating Financial Mechanism for pandemic prevention, preparedness, and response and the Global Supply Chain and Logistics Network (GSCL) to facilitate equitable, timely, rapid, safe, and affordable access to health products for countries in need during public health emergencies [17]. Importantly, pharmaceutical manufacturers participating in the PABS system will play a crucial role in ensuring equitable and timely access to pandemic-related health products tailored to meet public health needs, with a particular focus on the needs of developing countries [17].

The adoption of the 2025 WHO Pandemic Agreement brings hope and common sense at a time of concern when pandemic preparedness remains a major global health challenge [19]. Over the past five years, valuable lessons have been learned from the COVID-19 pandemic, particularly in vaccine development and data sharing [20]. However, national and political agreements on funding and biosecurity, as well as collaboration between world leaders, have stalled but could be activated by the 2025 WHO Pandemic Agreement [17]. At a time of national and global funding cuts to research and development (R&D) in healthcare, it is notable that Article 9 of the 2025 WHO Pandemic Agreement emphasizes the need for sustained R&D, which received early and unanimous approval from Member States [17]. The 2025 WHO Pandemic Agreement not only highlights the importance of continually supporting science as part of pandemic preparedness but also emphasizes the need to invest in R&D infrastructure and skills, as well as in clinical trials [17]. Respect for equity and human rights is included as a principle, goal, and outcome of pandemic prevention, encompassing participation in clinical trials, research outputs, and equitable access to and sharing of data [17].

The next round of negotiations aims to develop the Pathogen Access and Benefits Sharing (PABS) system (Article 31.2) through an Intergovernmental Working Group (IGWG), which will be considered at the 2026 World Health Assembly [17]. If adopted, the Pandemic Agreement will take effect in 2026 [17]. The Pathogen Access and Benefits Sharing (PABS) system, currently an annex to the WHO Pandemic Agreement, is based on the WHO Pandemic Influenza Preparedness (PIP) Framework [21,22]. The PABS system aims to provide a mechanism to achieve equity in the 2025 WHO Pandemic Agreement by addressing two main areas: ensuring that scientists and public health researchers have access to samples to identify pathogens and genetic sequencing data and securing products that include diagnostic kits, vaccines, and therapeutics for distribution to countries during a pandemic [21,22]. Following lessons learned from the COVID-19 pandemic, the PABS system also aims to secure samples for research and development (R&D) and provide a legal mechanism for equity in low- or middle-income countries (LMICs) for access to diagnostic kits, vaccines, and therapeutics from the pharmaceutical market [21,22]. However, even before the PABS system has been finalized, several challenges have been identified that remain to be negotiated [21,22]. The current 2025 WHO Pandemic Agreement outlines minimal standards for a PABS system, leaving many details to be determined in future negotiations [17]. For example, a focus has been on human samples and information, although the majority of emerging infectious diseases are zoonoses [21,22].

Additionally, current negotiations have yet to address international environmental law regarding access and benefit-sharing rules for indigenous and local communities, as well as ensuring that benefits outweigh costs, including those of manufacturers [21,22]. The distribution of vaccines, therapeutics, and diagnostics will be based on public health risk and need; however, the definitions of risk and need require further clarification [21,22]. The PABS system is expected to include private contracts or Standard Material Transfer Agreements (SMTAs) between the WHO and participating manufacturers, but it is unclear how these contracts will be evaluated by contractors and stakeholders [21,22]. Other factors that remain to be negotiated in the PABS system include tracking and tracing materials and sequence information, pathogen digital sequence information (DSI), database access and use, and striking the right balance on intellectual property (IP) rights [21,22]. The WHO Member States have yet to resolve these issues with the PABS system annex document in the past three years, which means that the next year will be crucial to the success of implementing the 2025 WHO Pandemic Agreement.

Conclusions

The implementation and success of the 2025 WHO Pandemic Agreement will depend on the support of heads of government and the provision of sustainable financing for its implementation in all countries. It is important to recognize that the 2025 WHO Pandemic Agreement now complements the revised International Health Regulations, which were adopted in 2024 [11]. Both the revised 2024 International Health Regulations and the 2025 WHO Pandemic Agreement outline principles and mechanisms for countries to collaborate in preventing, predicting, and responding to potential threats to public health from pandemics [11,17].