“One Health”: Responding to Pandemics with a Holistic Approach to Human, Animal and Environmental Health

How the Invasion of Natural Environments Backfires

Where did the coronavirus come from, pangolins?  Bats?  We still don’t know the exact circumstances behind its outbreak in China in late 2019, but there is one thing we are sure of since the global Covid-19 epidemic began: invasive human activities have had disastrous effects on the biosphere, and often backfire spectacularly. 

The examples continue to multiply: Ebola, H5N1, Marburg, Nipah, SARS, HIV, West Nile, and Zika viruses: they have resulted from close human contact with wild animals and pathogens. In one case deforestation forced bats to move closer to inhabited areas; in another case, expansion of farmland exposed laborers to natural reservoirs of pathogens; and in several regions, climate change has created conditions that favor the arrival and breeding of mosquitoes in new areas.

“Risks of contamination grow from several factors: increased human contact with new natural environments that are potential reservoirs of pathogens, trade in wildlife, domestic animals and wildlife kept in captivity in close quarters, and intensive livestock farming under deplorable sanitary conditions in urban peripheral areas,” says Gilles Kleitz, Director of the Ecological Transition Department at Agence Française de Développement (AFD). 

In fact, three out of the five or so new diseases that appear each year originate in animals. And – as we can see today with the Covid-19 crisis – we may be able to use medicine to treat human beings now, but it’s of no use in preventing or anticipating the risk of a future epidemic.

A New Outlook on Health

Reducing these risks will depend on an acknowledgement of the interdependence among three fields of health. That is the new outlook embodied in One Health, an approach that emphasizes greater cooperation among professionals in different fields on national and regional bases.

“When doctors, veterinarians, ecologists, agronomists, sociologists and anthropologists can all contribute their views, we can better understand the multifaceted aspects of a problem,” says Marie Edan, Head of the Project Team for Agriculture, Biodiversity and Rural Development at AFD, and veterinarian by profession. “Mad cow disease made us realize just how blurry the boundary is between animal and human health.”

Preventing Diseases at the Source

The One Health concept was developed in the early 2000s. Three international organizations began to implement it in 2010: the World Health Organization (WHO), the World Organisation for Animal Health (OIE), and the Food and Agriculture Organization of the United Nations (FAO). In the early years, particular emphasis was placed on the control of zoonoses (diseases communicable between animals and humans, such as rabies), antimicrobrial resistance, and food safety.

The three organizations signed a memorandum of understanding in 2018 to fight future health threats. They are working together to develop stronger national and regional services covering human and animal health and food safety, to promote research for better understanding of diseases of animal origin, and to detect those disease occurrences faster in an effort to stop them from spreading.

According to the OIE, prevention of diseases at the source is the most effective and economical solution to protect humans. The organization argues that veterinary services can play a crucial role in this prevention. By protecting animal health and well-being, veterinarians cab improve human health and food security, in particular through better control of livestock.

However, many countries, particularly in Africa, have for several decades been suffering from state withdrawal from animal health services, with serious public consequences.“We are encouraging governments to establish interministerial working groups to develop strategies that combine human, animal, and environmental health,” says Monique Eloit, Director General of the World Organisation for Animal Health. “One Health is a state of mind, an approach that everyone can adopt as their own. Many topics need to be viewed through that lens and addressed through joint action.” 

Regional Surveillance Network

In 2009, for example, AFD supported the creation of a network for epidemiological surveillance and alert management. It is coordinated by the Indian Ocean Commission in five countries: the Union of the Comoros, France, Madagascar, Mauritius and the Seychelles. In 2013, this group established a unit for animal health, and joined forces with the regional surveillance network led by CIRAD, a French agricultural research and international cooperation organization.

“We provide backing for a team of epidemiologists in the collection and sharing of field data,” says Patrick Dauby, Project Head at the AFD Health Division. “When a human and animal health alert occurs, samples are taken and an investigation is made to obtain precise information based on weak signals as quickly as possible.” In the Comoros, veterinary services investigated a case of animal-to-human transmission of Rift Valley fever in 2016. By investigating up the chain, the specialists discovered that livestock imported into the country was not systematically subject to health checks.

Innovative NGO Projects

“In Morocco, Libya, and Chad, we provide support for a project carried out by the Commission for Controlling the Desert Locust. Swarms of these locusts can consume up to 100,000 tons of organic matter per day and threaten the food production of whole regions. The project will improve surveillance of locust populations, in particular via computer models than can identify areas at risk of locust multiplication. That way we can focus prevention efforts on at-risk areas.” says Marie Edan.

In May, AFD also launched a “FISONG” (a periodic innovation facility for NGOs) with a budget of €2.5 million. Its aim is to fund one or more projects that implement an innovative One Health approach in Africa – projects that promote prevention, above all.

For now, few projects focus on issues other than zoonoses, but several have been created with the environmental and climate-change aspects of the One Health approach. The French Facility for Global Environment (FFEM) has supported a project in Uganda to develop agroecology and protect biodiversity north of the Kibale National Park. In parallel, the project is studying the impact of chemical pollutants commonly used in agriculture on human and animal health.

The European Union has taken up the approach, too. It has earmarked €90 million to a “One Health” research and development program over the 2018-2022 period. It brings together some 40 European organizations, including ANSES, the French Agency for Food, Environmental and Occupational Health & Safety.

From Concept to Reality on the Ground 

Though expanding, One Health is still in its infancy in operational terms. According to a study published in Lancet Planetary Health, about a hundred organizations were working on projects using at least two of the One Health components in Africa, Asia, and Europe at the end of 2017. “The concept will grow in importance and become more concrete in the years to come,” says Patrick Dauby. “The current health crisis sheds new light on the urgent need to design public policies that incorporate the One Health components.”

Meanwhile, the Covid-19 crisis is highlighting the lack of resources allocated to health systems in different parts of the world. Indeed, in their strategies to fight the spread of the coronavirus since the start of the epidemic, most countries have implemented such measures as lockdowns, mask-wearing, and social distancing – effectively putting most of the burden on their populations.  “This crisis is a tragic reminder that health is a social good," says Patrick Dauby. "And when we don’t invest enough, we pay a much higher price economically and socially."

For Monique Eloit, countries that have already adopted or experimented with health approaches that simultaneously consider humans, animals, and the state of the environment have proven to be best prepared to deal with the pandemic.

“The problem we currently face is weak health facilities. We spend a lot of money on polio immunization and tuberculosis screening, and – while those are important – it comes at the expense of hiring enough health professionals with suitable training," says Monique Eloit, OIE Director General. 

While One Health emphasizes the human and animal components, the focus may be too short-term and to the detriment of the health of the ecosystem, which faces continuing, long-term threats. Climate change already has many effects on human health, and the decline in biodiversity poses grave threats, notably to our food security.

“Whatever happens, we must shift towards a balance of the overall ecosystem,” observes Marie Edan. For that equilibrium to be attained, One Health will have to become not just a concept, but a way of life.