Global health security: from reaction to resilience

Global health security — the collective capacity of countries to prevent, detect and respond to public health events — is at a crossroads. Conceived for a world of discrete outbreaks, this approach has traditionally focused on the rapid containment of infections and cross-border health emergencies. But today’s health threats are increasingly complex and interconnected, and they do not arrive one pathogen at a time. 

Converging crises are exposing the limits of this reactive, singular and fragmented model. The COVID‑19 pandemic, along with multi-country outbreaks of Ebola, mpox and dengue have revealed how current global health security approaches struggle to keep pace with existing, emerging and re-emerging threats — and how they must shift from reactive, siloed responses to integrated resilience. 

Responding to emerging and evolving disease threats

The alarming pace of change and complexity of vector-borne and zoonotic infectious diseases is a wake-up call to how critically a shift for global health security is needed. Transmitted between animals and humans, directly or through other organisms, they emerge at the intersection of climate, environment, human behaviour and animal health. 

An effective framework to respond to these disease threats entails moving beyond episodic and emergency response to address upstream drivers of these diseases, such as climate change, urbanization, human-animal interactions and the changing role of information. This would improve health systems’ resilience and response to multi-pathogen and complex outbreaks.   

As vector-borne and zoonotic diseases adapt and spread into new geographies, they disproportionately affect populations with limited access to health services and essential resources, including refugees and people living in informal settlements. Together with surveillance systems that were not designed for such complexity, the current spread of these diseases exposes the limits of existing approaches, and demonstrates how resilience to these threats can be strengthened by applying integrated, equitable and locally grounded strategies. 

Where current global health security approaches fall short

Despite decades of investment, global health security systems often respond to outbreaks once they escalate, rather than anticipating emerging risks. Surveillance and data sharing systems are often designed to be disease-specific, which misses complex outbreaks involving multiple pathogens, and they frequently wane after outbreaks slow down or dissipate. Moreover, many countries rely on centralized, top-down systems that are slow to respond and often overlook local or Indigenous knowledge. 

Meanwhile, climate change is accelerating the spread of diseases such as dengue, malaria and Lyme disease, and creating conditions for new threats. Rising temperatures, shifting rainfall patterns and extreme weather events are changing habitats where vectors such as mosquitoes, ticks and flies can survive and spread, bringing diseases to regions where they were previously underreported.  

Antimicrobial resistance is further compounding these risks by reducing the effectiveness of existing treatments for bacterial infections. At the same time, population displacement, driven by conflict, economic pressures and climate shocks, is reshaping disease dynamics in ways that traditional global health security frameworks struggle to capture. For example, during the Sudan conflict that forcibly displaced more than 15 million people, the country faced one of the worst cholera outbreaks in recent times. 

All the while, misinformation and disinformation about outbreaks are eroding public trust in health institutions and science, weakening the social foundations required for prompt and effective responses.  

Taken together, these intersecting pressures point to a strategic opportunity: we can improve global health security using approaches that are collaborative, community-driven, equitable and integrated. A framework that considers the complexities of vector-borne and zoonotic diseases can help ground these efforts and improve the chances of success. 

Reframing global health security in a polycrisis world

Using a framework that looks at vector-borne and zoonotic diseases goes beyond single pathogens or groups of closely related diseases and allows for a focus on the ecosystems, structures, behaviours and inequities that shape risk. As a result, it is critical to reframe global health security around the disease threats emerging at the human-animal-environment interface, with emphasis on how they are shaped by climate, mobility and socio-ecological change. 

To transition from reactivity to resilience, global health decision-makers, funders and policymakers must rethink global health security. Priority investments should support: 

• Credible and accessible community-level data. Data needs to be trusted by local communities. This requires sustained investment in local research institutions, data collection methodologies, and mechanisms to analyze and use the data to shape community-level decisions. 
• Surveillance and early warning systems. These systems are the first line of detection and response. A robust set of systems capturing human, environmental and animal health data can detect unusual patterns earlier. Advances in modelling and analysis, including the use of responsible artificial intelligence solutions trained on local data, can support prevention, preparedness and response efforts. 
• Monitoring pathogen dynamics. While systems and ecosystems shape risk, targeted attention to how single pathogens or groups of pathogens evolve and interact cannot be underestimated. Investments should support integrated research, surveillance and response strategies that anticipate pathogen evolution, antimicrobial resistance and cross pathogen dynamics. 
• Equity-centred approaches. Prioritizing equity and inclusion, with attention to legal, social and gender norms and systemic discrimination ensures marginalized populations are not overlooked, and interventions are designed together with affected communities. 

Solutions-driven investments for a healthier future

As vulnerabilities expand and shift, so must research and funding priorities. Investments should bridge research, innovation and policy, supporting regional leadership in decision-making and enabling response mechanisms that address compounded climate, disease and health system threats.  

IDRC’s long history of supporting projects through a systems approach, balancing short-term and long-term needs to both prevent and respond to animal-to-human diseases, shows how locally led research can generate solutions that are scientifically robust, credible and socially grounded. Building on these lessons will be essential to strengthening outbreak prevention and preparedness and to promoting a more equitable and resilient global health security architecture — one that is fit for a changing world and that can benefit communities everywhere.