The increasing awareness of just how interconnected the systems are that intertwine the lives of animals, people and their environments—and each one of their healths—has come to be expressed as “One Health”. As the human and animal global populations swell, the latter in large part to keep pace with growing food needs, human actions are placing enormous pressure on the viability and safety of the planet. Humans and their crops and livestock exact a toll on the environment; encroaching on pristine ecosystems for agriculture and development, exacerbating climate dynamics, exhausting soils and altering landscapes or contributing to further desertification. Greater urbanisation and sharp increases in international trade and transport—and the impressive speed with which pathogens can instantly become global, such as influenza, mean that in order to better protect global human health, greater care must be given to maintaining the health of ecosystems and animals. Two out of three new diseases in humans originate in the animal world—70 % of those from wildlife animals in particular (Jones et al. 2008). However, livestock raising also makes up 40 % of global agricultural GDP (FAO 2009). Livestock is especially critical in developing countries, where one billion of the poorest farmers depend on livestock for basic protein and as a way of making a living (Ashley et al. 1999).

One Health eludes any precise definition, making it hard to convey as a concept. FAO, like many, have resisted efforts to define it, recognising that part of its strength lies in the fact that it remains open to a range of disciplines that can contribute to global health. The importance of the term lies its interdisciplinarity—required for tackling complex challenges such as health, which is a continuum from the local to the global level. Although to date the effort and concept have been principally focused on infectious diseases, it is recognised that causation of disease states and the promotion of overall health is much broader. For safeguarding health, cohesion of collective efforts to improve nutrition and better understand the role of ecosystems in health requires exploration. For example by providing ecosystems services, biological diversity is maintained, thus benefiting improved biological resilience that provides a buffer against extreme events.

From an infectious disease perspective, FAO has established systems in prevention, detection, preparedness and response to better address threats at global and local levels (i.e., H5N1 avian influenza, foot-and-mouth disease, rabies, brucellosis, other high impact diseases). Critical to this work are FAO’s collaborative agreements with the World Organisation for Animal Health (OIE) and the World Health Organization (WHO), another UN agency, as a tripartite working to promote One Health in common areas where synergies can be found (such as zoonotic agents, antimicrobial resistance, disease intelligence). The tripartite, individually and collectively, is involved in setting standards, improving governance and quality control mechanisms for health, as well as honing prevention efforts, developing early warning alerts and timely responses to disease events around the world and gaining better understanding of the drivers to disease emergence, maintenance and spread. Zoonotic diseases and high impact animal diseases that have ruinous impacts on human health, livelihoods and commerce are given high priority.

FAO embraces the One Health approach by engaging the depth of resources and expertise it has as an organisation across the disciplines it has in-house: FAO has over 3,000 employees ranging from veterinarians, wildlife specialists, microbiologists, nutritionists, sociologists, lawyers, anthropologists, bioinformaticians, water engineers, crop economists, development communicators and extentionists, molecular biologists and emergency and relief responders. FAO is a One Health organisation.

Healthy animal production systems—terrestrial and aquatic; domestic and wild—converge with efforts to feed the world and manage natural resources sustainably, reducing the risk for disease outbreaks by implementing sound agricultural and development policies that improves people’s food security and source of livelihood. FAO as an organisation, and in its One Health work, fosters community participation and gender equity in terms of resources, informations, goods, services and decision-making in rural and urban areas. The approach calls for increased public and private investments to strengthen existing agriculture and development systems and an enabling environment in which to do so. Getting wholesome food to the cities, with enormous peri-urban populations living in unhygienic conditions, remains a challenge for FAO and the One Health agenda.

While many issues are “One Health” issues, FAO’s animal health service has prioritised actions and activities focusing on some ten priority infectious diseases because of their impact on food security, socio-economic importance, transboundary spread, food safety or economic security¹ and other cross-cutting issues such as antimicrobial resistance, information and surveillance systems between veterinary, wildlife and public health sectors, planning and preparedness. For FAO, the One Health priority issues extend beyond emerging and re-emerging infectious diseases, as some of the known and ancient diseases that have not been successfully addressed or curbed would benefit from an inter-disciplinary and multi-sectoral approach (i.e., tuberculosis or rabies). However, tackling single pathologies is likely not cost effective or efficient in the long run and a more encompassing approach would and could improve health across a production systems based on species or sector (i.e., small ruminant health, dairy sector). Having hygiene and biosecurity concepts practiced as if they were second nature can eliminate numerous disease threats; flock or herd health can include vaccination and treatment of the young stock for those high risk/high impact diseases.