Bridging Climate Action and Health Security through One Health

Climate change is increasing the risk of infectious disease outbreaks, threatening health security around the world.

As world leaders gather this week for the 81st session of the United Nations General Assembly (UNGA 81), Africa’s experience shows why climate change and health cannot be separated.  A One Health approach is essential to managing growing risks at the intersection of people, animals, and the environment. World leaders should prioritize One Health to address growing risks.

One Health recognizes that human health cannot be separated from our environments

Most emerging infectious diseases originate at the interface between humans, animals, and the environments they share, making cross-sectoral, evidence-driven responses essential to effective health security.

Climate change exacerbates the risk of zoonotic spillover, as shifting rainfall patterns, habitat disruption, and rising temperatures expand the range of disease vectors and pushing wildlife, livestock, and human beings into closer contact.  Globally, nearly 60% of emerging infectious diseases and 75% of new human pathogens detected over the last three decades have originated from animals.

Africa’s disease landscape reflects this reality. Over the last decade, zoonotic outbreaks in Africa, including diseases such as mpox, Ebola, Lassa fever, and Marburg virus, among others, increased 63 percent compared to the previous decade. And given the interconnectedness of the modern world, a zoonotic disease outbreak in one country can quickly become a global outbreak.

In the development of the Africa Health Security (AHS) Index, African experts on our Reference Group highlighted how Africa’s unique disease landscape influences the ability to detect, monitor, and respond to biological threats across the continent. A One Health approach is critical to addressing this gap.

AHS Index reveals progress and critical gaps

Since 2021, African countries have strengthened their capacities to respond to biological threats. Capacities to prevent, detect, and respond to zoonotic diseases increased by 11.1 points, from 28.6 in 2021 to 39.7 in 2026. Access to basic water and sanitation infrastructure, a critical element of preventing water-borne outbreaks such as cholera, also improved. In 2026, the average percent of households with access to water increased to 69% from 51% in 2021. Similarly, 46% of households have access to sanitation infrastructure, up from 38% in 2021. More than half of countries now have a strategy or plan to build resilience to climate change.

Despite this progress, gaps remain. Just 43 percent of African countries conduct disease surveillance in animal populations despite the growing risk of zoonotic spillover events that affect human health. Many African countries are also at risk for economic disruption due to natural disasters, with 54% of countries facing very high- or high-risk levels.

Regional institutions such as Africa CDC and the African Development Bank are central to closing these gaps, and intergovernmental organizations such as the World Health Organization have acknowledged One Health as an integral component to advancing global health security.

A path forward 

To further strengthen preparedness capacities across the continent, the AHS Index recommends adopting a One Health approach to disease surveillance. To advance this goal, African national governments, regional entities, and other stakeholders can:

• Integrate surveillance data from domestic and wild animal populations into existing public health surveillance platforms
• Convene ministries of health, agriculture, environment, and wildlife alongside community members to develop response readiness strategies and protocols in case of zoonotic outbreak
• Draw on existing strategic frameworks, such as the Africa CDC’s Framework for One Health Practice in National Public Health Institutes to bolster climate action and health security capacities

The AHS Index shows that African countries have already prioritized a One Health approach, building the surveillance systems, legislation, and partnerships necessary to advance pandemic and epidemic preparedness. But progress remains uneven, and climate-driven biological risks are accelerating faster than many health systems can adapt.