Vector-borne diseases (VBDs) are emerging as a significant threat to both human and animal health, with recent years seeing a troubling increase in their prevalence and spread. The World Organisation for Animal Health (WOAH) has highlighted this growing concern in their latest report “Animal Health Situation Worldwide” covering 2023 and early 2024, presented during its 91^st General Session. This analysis brings some additional elements related to the intricate relationship between climate change and the dynamics of VBDs, underscoring the urgent need for effective surveillance and control measures.

Climate change’s impact on
vector-borne diseases (VBDs)

VBDs, which include diseases transmitted by vectors such as mosquitoes, ticks, and flies, thrive in certain environmental conditions. The climatic conditions of tropical regions make them particularly vulnerable to these diseases. However, climate change is reshaping this landscape, altering vector density, activity periods, and geographical distribution. These changes facilitate the expansion of VBDs into new areas, posing significant risks to previously unaffected regions. 

WOAH’s report on the “Animal Health Situation Worldwide” underscores the complexity of this issue, noting that both biological and non-biological pathways influence VBD transmission. There is clear evidence that climate change is a critical driver in the spread of these diseases. Observational data corroborate this, showing an increasing trend in the maximum latitudes at which VBDs are reported, closely mirroring global temperature anomalies.

Revealing emerging trends 

Data reported through the early warning system of the World Animal Health Information System (WAHIS), from 2023 and early 2024 (as of 11 March 2024), reveal that VBDs were responsible for a total of 2,422 outbreaks across 28 countries and territories, in the context of exceptional epidemiological events. These events mainly include first occurrences, recurrences and new strains. The Americas notably experienced a large outbreak of western equine encephalomyelitis, with 1,461 outbreaks, while Europe reported 697 outbreaks of various VBDs. 

Of the 90 diseases of terrestrial animals currently listed by WOAH, almost a third are vector-borne (entirely or for which vectors play an important role), some of which have shown a significant evolution in 2023 and early 2024.

Infection with West Nile fever virus, bluetongue virus, lumpy skin disease virus and western equine encephalomyelitis virus were the most frequently reported in 2023 and early 2024, in the context of exceptional events. Infection with lumpy skin disease virus, for which exceptional events were predominant in Asia, accounted for 144 outbreaks, making it the most reported VBD outside Europe and the Americas through early warning. Notably, 99% of these VBD outbreaks in 2023 and early 2024 were detected in temperate regions, indicating a worrying shift in their geographical distribution. 

Monitoring the expansion of VBDs 

These challenges are not new and date back several years. In response, WOAH had launched in 2022 the PROVNA project, aimed at enhancing VBD surveillance in North Africa. This initiative seeks to define ‘ecoregions’ within the study area, identify vulnerable zones, and develop a prototype application to predict climatic and environmental changes.  

A notable case study presented in the report is the recent spread of infection with epizootic haemorrhagic disease (EHD) virus. Traditionally confined to regions like North America and parts of Asia, EHD has expanded its range significantly since 2006, with new reports from countries around the Mediterranean and into Europe. This spread exemplifies the broader trend of VBD expansion driven by climate and environmental changes. 

Taking action for global health 

WOAH’s report paints a vivid picture of the escalating threat posed by vector-borne diseases in the context of climate change. As it stands at its centenary, WOAH reiterates the need for robust surveillance systems, international collaboration, and adaptive strategies to manage this growing challenge. As climate change continues to influence the spread and impact of VBDs, the global community must respond with urgency and innovation to safeguard both human and animal health. Because animal health is our health. It’s everyone’s health. 

For more detailed insights, explore the full report.

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After seven successful years, one of the World Organisation for Animal Health’s flagship projects, EBO-SURSY, is coming to a close. Highlighting its significant impact on animal health, the project has produced a final impact report underscoring its commitment to improving everyone’s health. The primary focus of this EU-funded program has been on the protection of wildlife health, and the health of the human communities who live beside them. 

Partnered closely with ten countries in West and Central Africa, the project applied a One Health approach, strengthening national and regional early detection systems for zoonotic wildlife diseases. By improving ways to detect and prepare for outbreaks of viral haemorrhagic fevers like Ebola and Lassa fever, the EBO-SURSY Project has helped build a healthier world for animals and humans alike. 

Empowering the animal health workforce

A key component in strengthening a health system is investing in personnel. Without technical knowledge, techniques, material, or resources to excel in their profession, staff cannot thrive and perform to their best ability. To bridge these gaps, the
EBO-SURSY Project hosted a wide range of capacity-building activities, including training programmes and scholarships. It gave animal and human health stakeholders all along the chain the means to build robust surveillance systems in their countries, which will encourage long-term, positive impacts.  

In addition, the project has also given stakeholders the opportunity to network and build relationships across the One Health spectrum, including animal, human, wildlife, or environmental health professionals. These strengthened relationships are the backbone of a comprehensive health system.   

Building trust with communities 

Because of zoonotic spillover, humans and wildlife alike are increasingly vulnerable to many diseases such as viral haemorrhagic fevers. People living near or within natural ecosystems such as rainforests are generally isolated and lack access to information on how to safeguard themselves, wildlife and domestic animals.  

Informed communities are empowered to protect themselves, other humans and wildlife, and EBO-SURSY was committed to building their knowledge. By looking out for tell-tale signs of zoonoses, including unusual deaths and behaviour in wildlife, local communities are the first in line to alert national Veterinary Services or wildlife authorities.

The EBO-SURSY Project, in partnership with local journalists and youth reporters, reached out to communities through radio campaigns focused on raising awareness on wildlife diseases and prevention strategies.

Overall the efforts of the project led to:

Predicting and preventing outbreaks 

Building capacity and raising community awareness are essential steps in establishing strong national surveillance systems, but they are not enough. It’s imperative for countries to implement plans to monitor pathogens and provide clear, accessible guidance for both professionals and the public during an outbreak. 

To empower national Veterinary Services and wildlife professionals build effective surveillance protocols step-by-step, the EBO-SURSY Project held several regional workshops. Some attendee countries went further, holding national-level workshops with EBO-SURSY support, to refine their draft protocols for priority diseases and to gain national support to pass them into legislation.

Because efficient surveillance protocols must be grounded in scientific fact, the
EBO-SURSY Project was committed to scientific research on key viral haemorrhagic fever diseases. It organised field investigations and supported multi-scale research through its consortium partners, Le Centre de coopération internationale en recherche agronomique pour le développement (CIRAD), Institut de recherche pour le développement (IRD) and Institut Pasteur. 

All three are known for their scientific excellence in the prevention and control of zoonoses, and worked with local stakeholders in the project countries with the aim of providing data-driven predictive models and risk assessment tools. 

• 197 field investigations to support scientific research of 5 viral haemorrhagic fevers, coronavirus, monkeypox and more.  
• 43,000 animal samples and 6,000 human samples taken to track diseases at the animal-human interface and improve scientific studies.  
• 43 scientific studies were published as a result of EBO-SURSY funded research in the fields of ecology, genetics and socio-economics.  
• 25 methodologies and diagnostic tools have been improved or developed.

A new future for wildlife health  

As the EBO-SURSY Project concludes its commitments this year, it is about to enter a new phase with the support of the European Union.  

Over the next years, it aims to expand its geographic scope to 17 countries and include more scientific partners, as well as additional One Health stakeholders. The project will go even further in helping national Veterinary Services set up efficient surveillance systems, and apply scientific findings from phase one into policy, legislation, and professional guidance to safeguard health. 

 

Over 50 million people worldwide depend on fisheries and aquaculture for their livelihoods. However, aquatic animal diseases can jeopardise the economic and environmental sustainability of this source of income. For instance, on a global scale, disease outbreaks cost the aquaculture industry over US$6 billion per year. 

As the emergence of new diseases is likely to continue, driven by factors such as climate change, unsustainable farming practices or unregulated trade, careful management of the health of aquatic animals is crucial. Most of these diseases severely impact the aquatic animal production sector, but also the open ecosystems in which these populations often live. 

The World Organisation for Animal Health has been at the forefront of preserving the significant contributions of aquatic animals, supported by its international network of experts for over 50 years. 2021 marked the launch of its global Aquatic Animal Health Strategy: an ambitious call to action to improve the sustainability of aquatic animal health systems. 

Guided by this strategy, we are bringing together different actors from the international community to coordinate joint actions in response to the challenges met by the aquatic sector. By working together, we can make our vision of improved aquatic animal health and welfare worldwide a reality.  

The OIE Aquatic Animal Health Strategy is a cornerstone towards more sustainable aquatic ecosystems.

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Animal Welfare and the United Nations Sustainable Development Goals

The 3rd OIE Animal Welfare Global Forum provided a platform for information sharing about the SDGs and how animal welfare plays a role in achieving the SDGs, an exchange of ideas and perspectives, and the development of proposals for future work.

Consult the PTT of the 3rd OIE Animal Welfare Forum:

1. OIE Global Animal Welfare Forum and OIE Animal welfare activities, Matthew Stone, OIE Deputy Director General
2. United Nation Sustainable Development Goals, Isaiah Otieno, United Nations Environment Programme (UNEP)
3. Example of linkage: Dog population management, Alexandra Hammond-Seaman, ICFAW
4. Example of linkage: Beef cattle production, Francisco Galindo, UNAM, OIE Animal Welfare Collaborating Consortium for the Americas
5. Animal welfare and the Sustainable Development Goals, Linda Keeling, Swedish Centre for Animal Welfare (SCAW)
6. Examples of linkage: Pig production systems, Jacques Servière, IMS
7. Examples of linkage: Farm fish production systems, Stian Johnsen, OIE Standards Department

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