One world, one health
The world is becoming a smaller place - more people travel, trade is global and the sheer number of humans and livestock existing on this planet is more than it has ever been. With all these changes, it is becoming easier for diseases that originate in animals (zoonotic diseases) to infect humans and to rapidly spread across the globe.
In order to protect human health, public health experts are focusing their attention on preventing the emergence and spread of new and existing diseases - diseases such as H1N1, Avian Influenza, Lyme disease, West Nile virus, Monkeypox and Mad Cow Disease (also called bovine spongiform encephalopathy).
These diseases are complicated by the fact that their spread from animals to humans is influenced by many factors related to animal, human and ecosystem health. West Nile virus is a good example. This virus is transmitted to people through the bite of a mosquito and can lead to paralysis or death. Public health experts must consider the dynamics of mosquito populations (abundance, length of breeding season, breeding conditions), the types of birds that carry the virus and their migration patterns, and environmental conditions (climate change) that create favourable mosquito breeding conditions. In this case, public health experts need to look at strengthening areas of animal health and the environment in order to protect human health.
This integrated, holistic and preventative approach to protecting human health is referred to as One World One Health, a name coined by the Wildlife Conservation Society in 2004.
The Wildlife Conservation Society periodically holds meetings to discuss One World One Health. At their first meeting on this topic in 2004, the Society released the Manhattan Principles - 12 principles highlighting the importance of animal health, ecosystem health and human health in the prevention of zoonotic diseases.
Since then, six major international organizations (the World Health Organization, the Food and Agriculture Organization, the World Organization for Animal Health, the United Nations Children's Fund, the United Nations System Influenza Coordination, and the World Bank) have developed a framework on One World One Health. In 2009, the Public Health Agency of Canada hosted an Expert Consultation to discuss the ways in which One World One Health could be moved forward. Participants recommended finding better ways to share data, work together across fields and build expertise in developing countries.
The One World One Health concept continues to emerge all over the world. Better understanding of the relationships between animal health, human health and ecosystem health is needed to protect public health. No single sector or country can achieve this alone. The strength of One World One Health is that it relies on cooperation and partnership across disciplines and among countries to protect a common global interest - effective public health.