WOAH has launched the Guidelines Mitigating Disease Transmission Risk at the Wildlife–Livestock Interface to Facilitate Safe Trade, providing Veterinary Services with practical guidance to manage disease transmission risks where wildlife and livestock interact. The guidelines respond directly to Members’ needs to control transboundary animal diseases while maintaining continuity of safe national and international trade.

Why Did WOAH Develop These Guidelines?

Transboundary animal diseases (TADs), such as African swine fever (ASF), avian influenza (AI) and foot and mouth disease (FMD) continue to spread worldwide, with serious consequences for animal health, trade and livelihoods. In many countries where these diseases are endemic, infections can pass between wild and domestic animals, sustaining infection transmission cycles that are difficult to control because of the complex factors and risk pathways involved.

Importantly, for some diseases, WOAH standards allow the recognition of animal health status in effectively separated subpopulations and require that Members do not ban international livestock trade on the sole ground of disease occurrence in wildlife.

In this context, Members have requested WOAH guidance on managing risk at wildlife–livestock interface (WLI) for disease control purposes, while preserving the animal health status of domestic subpopulations for business continuity.

How Were the Guidelines Developed?

In 2024, WOAH launched a consultancy to develop technical guidelines addressing disease management at the wildlife–livestock interface.

The guidelines were authored by Prof. Christian Gortázar, Dr Joaquín Vicente and Dr Ursula Höfle from the Instituto de Investigación en Recursos Cinegéticos (IREC), Universidad de Castilla-La Mancha and the Spanish National Research Council (CSIC), Spain—an internationally recognised team with extensive expertise in this field.

In January 2025, the first draft underwent peer review by a WOAH ad hoc Group, which provided expert opinions and recommendations while ensuring that regional perspectives were considered. The WOAH Scientific Commission for Animal Diseases (SCAD) also reviewed the draft to confirm scientific soundness and alignment with WOAH international standards. Additionally, the WOAH Working Group on Wildlife  was consulted to ensure wildlife-related aspects were accurately addressed.

Following these reviews and revisions, the guidelines were officially published on the WOAH website in December 2025.

How Should the Guidelines Be Used?

The guidelines offer practical approaches for managing disease spillover risk between wildlife and livestock across a wide range of farming systems. They propose a structured methodology enabling Veterinary Services to manage WLI scenarios through customised risk mitigation programmes tailored to local conditions and needs.

Rather than offering prescriptive solutions, the guidelines present a flexible framework for addressing wildlife–livestock interfaces. Case studies and field examples illustrate how risk mitigation measures can be adapted to different epidemiological contexts.

Effective disease risk management must be tailored to local realities, taking into account geography, production systems, wildlife species and the target disease. All interventions should align with WOAH international standards and relevant national regulations.

Their effective use requires a solid background in veterinary sciences, particularly disease epidemiology, and benefits from knowledge of wildlife ecology. A clear understanding of the specific WLI scenario, farming practices and key risk pathways is essential for successful implementation.

WOAH encourages Members to make use of the guidelines to better implement the provisions outlined in the international standards and to share their experiences with the Organisation.

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Resources

Recording of the launch webinar on 15 January 2026: Webinar: Launch of Guidelines ‘Mitigating Disease Transmission Risk at the Wildlife – Livestock Interface to Facilitate Safe Trade’ – WOAH – World Organisation for Animal Health

An interview with Dr William B. Karesh (Member of the Working Group on Wildlife and Executive Vice President for Health and Policy at EcoHealth Alliance). 

Briefly, what is El Niño? 

William B. Karesh: El Niño means Little Boy in Spanish. South American fishermen first noticed periods of unusually warm water in the Pacific Ocean in the 1600s. The full name they used was El Niño de Navidad, because El Niño typically peaks around December. During normal conditions in the Pacific Ocean, trade winds blow east to west along the equator, taking warm water from South America towards Asia. To replace that warm water, cold water rises from the depths — a process called upwelling. El Niño and La Niña are two opposing climate patterns that break these normal conditions by weakening trade winds. Scientists call these phenomena the El Niño-Southern Oscillation (ENSO) cycle. El Niño and La Niña can both have  global impacts on weather patterns, causing extreme environmental events, such as wildfires, with strong societal and economic repercussions on our interdependent ecosystems.  Episodes of El Niño and La Niña typically last nine to 12 months but can sometimes last for years. El Niño and La Niña events occur every two to seven years, on average, but they don’t occur on a regular schedule. 

In which direct and indirect ways do weather events prompted by
El Niño–Southern Oscillation (ENSO) affect animal health? Which animals are affected the most?  

W.B.K: Weather conditions affect animal health both directly with temperature extremes/extreme temperatures and water availability (droughts and floods) as well as indirectly with changes in the availability of nutritional and food resources, abundance of vectors, and crowding, dispersal or movement of animals. The weather extremes may result in dehydration and mal-nutrition in both wild and domestic animals and increases in vector-borne diseases such as Rift Valley fever, yellow fever, and malaria. 

Since it occurs on a cyclical basis, should we be able to plan for it? What are the warning signs that ENSO is starting and how much time do we have to prepare? 

W.B.K: Using data collected from ocean buoys and satellite systems such as sea temperature, currents, and atmospheric conditions, climate scientists have developed predictive models that can forecast ENSO events with increasing accuracy several months in advance.  A key predictive indicator is a shift in Pacific trade winds and a lowering in ocean surface temperatures in the equatorial region of the western Pacific Ocean. While the specific degree and time length of the effects may vary a bit, the general pattern of the changes in different locations remain consistent across/in between ENSO events and thus can be used locally for planning purposes. 

What can be done by animal health services and environmental services to be prepared and resilient before an El Niño event? 

W.B.K: The first step is to review the impacts of previous ENSO events at the specific local or region level of concern and tailor preparedness and mitigation plans for the anticipated changes such as increased or decreased rainfall. This understanding of the potential impacts can then be used to develop plans that are locally relevant and engage key agencies and community stakeholders in planning and preparedness, as well as design communication strategies for different audiences.  Activities may include assuring availability of response equipment and supply stockpiles, refresher training of personnel, planning for water availability or flood control, contingency planning for feed/food availability and supply chains, outbreak or mortality event response capabilities, etc. 

How can we support unmanaged wild animal populations during climatic events? 

W.B.K: Where droughts are anticipated, access to water may bring livestock and wildlife into closer proximity. This allows for increased disease transmission from livestock to wildlife or to reduce safe access to water by wildlife. Access to water by people, livestock and wildlife can be discussed and planned by engaging relevant stakeholders and relevant authorities. Anticipated changes in ocean temperatures have predictable effects on fish populations and fisheries, and affect food stocks for marine birds and mammals. Fish harvesting quotas should be adjusted to avoid the depletion of fish stocks, and prevent the starvation of wildlife.

What is the Working Group on Wildlife doing to increase awareness of the impacts that extreme events have on wildlife health? 

W.B.K: The WGW released an early warning for the coming ENSO event for health authorities and the general public. It stands by to advise WOAH, its Members and other interested parties as requested and as the wildlife situation evolves.

You coined the expression “One Health” in 2003 to describe the interdependence of healthy ecosystems, animals and people. How has this concept evolved in the past twenty years, and what are the accomplishments of the One Health approach that underline its significance today? 

W.B.K: The increased attention to ENSO events provides an excellent example of growth of One Health thinking among different sectors that consider how environmental changes can have consequences on health and well-being. The One Health concept has become a starting point for the development of many programs and projects at local, national and international levels to expand cost efficiency and co-benefits. In financial terms, investments in using a One Health approach have exceeded tens of billions (USD) since its inception. 

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