The ‘One Health’ approach in a dynamic world

What is One Health?

Recently, it has become increasingly common to hear the term One Health used and the importance of applying this integrated approach that brings together human, environmental and ecosystem health. On the occasion of the One Health Day promoted by the One Health Commission, the One Health Initiative and the One Health Platform Foundation, we want to explore the importance of this approach and why in the global context it is more important than ever.

The One Health approach connects closely related and interdependent human, animal and environmental health to collaboratively address, prevent, predict and respond to global health threats. In other words, this approach proposes that the health of people, animals and the environment are intrinsically linked and that health problems in one of these areas have an impact on the others, hence the importance of incorporating it into public health.

Although the term ‘One Health’ is relatively new, this concept was already present in the scientific community in the 19th century. They saw certain similarities within the processes that occur during the course of a disease between animals and humans. It was a German physician, Rudolf Virchow, in the 19th century who coined the term ‘zoonosis’ and promoted the idea of establishing connections between human and veterinary medicine. However, it has been in the last few decades that the term ‘zoonosis’ has become more and more widely used.

Fig. 1. Multiple global changes in the human-animal-environment ecosystem that create tipping points for infectious disease outbreaks. Source: Netherlands Center for One Health.

The Importance of the One Health Approach to Zoonotic Disease Prevention in a Globalised World

In an increasingly globalised world, where population density is growing and climate change is defining new scenarios, this approach and the connections between these fields are key to address, control and prevent diseases. Specifically, to prevent zoonoses, diseases that can spread between animals and humans, such as dengue fever, or Zika, which are mosquito-borne diseases.

As of 2024, more than 12 million dengue cases and more than 8,000 dengue-related deaths have been reported in 86 countries/territories worldwide. Autochthonous (not travel-associated) cases of dengue have been reported in Europe, with 63 cases in Italy, 68 in France and 8 in Spain.

This situation exemplifies the need to work under this global public health approach. It is important to control mosquito populations (animal health) and their habitat (environmental health), in order to implement prevention measures (human health).

By mobilising multiple sectors, disciplines and communities at different levels to work together in a synchronised way, new ideas can be developed to address the causes and look for long-term solutions, such as biological mosquito control, monitoring and environmental management.

Mosquito Alert and its contribution to the One Health approach

Mosquito Alert contributes to this mission through projects such as the One Health Pact, VEO Project and E4Warning. These projects have in common the anticipation of infectious disease outbreaks in humans and animals, and focus primarily on vector-borne diseases, specifically mosquitoes.

The increasing spread of invasive mosquitoes in Europe, such as the tiger mosquito (Aedes albopictus), poses a risk because it can transmit diseases such as dengue, Zika and chikungunya. However, the presence of the common mosquito (Culex pipiens), also carries this risk, as this species can transmit viruses, mainly among birds, but which can occasionally be passed on to humans.

The ultimate goal of this project is to prepare integrated disease surveillance and early detection systems, as well as to promote community education to reduce the risks that may arise. In short, to create a network for an early and effective response to possible outbreaks.

Interdisciplinary work for a more effective response

As human, animal and environmental health are interrelated, the most effective way to strengthen our response to these new risks is to work in an interdisciplinary way. Breaking down the boundaries between disciplines and bringing together sectors such as veterinary medicine, animal health and the environment.