One-Health concept: Novel approach

All human health care practitioners, veterinarians, public health and environmental health professionals should consider the ‘One-Health’ approach as a professional imperative for the interest of co-existence of all the living beings

The Ebola virus disease outbreak beginning in 2013 had brought the world into a standstill. With more than eleven thousand deaths (there were still many unreported fatalities) and a rapid spread to five countries in West Africa, the outbreak was deemed worst since it was first reported in 1972.

Flights to and from those African nations were cancelled, travel sanctions were imposed, and albeit late, the World Health Organisation (WHO) declared the outbreak a “Public Health Emergency of International Concern” on August 8, 2014.

Following active participation of health workers from Doctors without Borders and aids from WHO, Centre for Disease Control (CDC) and other INGOs, the outbreak was assuaged eventually.

Investigations into the occurrence of the outbreak led scientists to track the Index Case (the very first person to become infected), a one year boy in Guinea. As it turned out, the boy had been in frequent contact with bats.

Epidemiologists have found a complex cycle connecting bats, the non- human primates (such as the Gorilla and Chimpanzee) and humans leading to the transmission of Ebola virus from one host to the other.

This finding renewed the concept of integrated investigation in human and animal population for the prevention, control and treatment of shared diseases.

One-Health is a novel approach employed in understanding how the diseases are shared among humans, animals and the environment. It is based on the understanding that the health of people is based on the health of the animals around them and the wholesomeness of the environment.

In the wake of recent pandemic threats due to zoonoses such as the Ebola and Influenza A, scientists have acknowledged the need for collaboration among the physicians, veterinarians and the environmentalists/ecologist to better understand disease dynamic and thereby devise competent strategies to detect, prevent and control the spread of diseases across species.

The One -Health approach seems imperative to curb one of the major challenges in the current world; that of emerging and re-emerging diseases of animal origin. According to the WHO and World Animal Health Organisation (OIE), at least 75 percent of the emerging infectious diseases of humans have animal origin and 60 percent of the existing human infectious diseases are zoonotic in nature.

Thus the main goal of the One-Health approach is to monitor, prevent and contain public health threats.

Some of the animal diseases have transcended the cross-species barrier to infect humans constituting a zoonosis. Increase in human population and subsequent encroachment of wilderness has led to frequent contacts of people and wild animals in human-wildlife interface areas.

Also the domestic animals and pets reared by people living in such areas are most often at the receiver end in the transmission of many diseases. Diseases transmissible to humans through bites of wild canines such as the Rabies, through insect bites such as the Rift Valley Fever and through contact such as the Ebola are the consequences of proximity of humans and wildlife.

There are also concerns over the vulnerability of human health due to climate shifts. The Inter-governmental Panel for Climate Change (IPCC) has suggested significant vulnerability for people around the globe due to shifts in weather patterns and climate variability.

Studies show that increase in temperature associated with climate change opens up new niches for disease vectors to thrive. These vectors are a major player in bringing animal diseases into the human population through bites. Spread of Zika virus, Lyme disease and Dengue fever are examples of such conditions.

Climate shifts, along with urbanization and globalization, have supported interaction, reformation and adaptation of pathogenic microbes leading to their increased virulence and, thus, imposing new threats to the health of both animals and humans.

Diseases causing problems in the human health sector have solutions in the veterinary sector. Rabies and E. coli gastroenteritis are the examples. Likewise, many animal diseases are due to environmental causes.

Since human and veterinary medical professionals are essentially taking care of the same pathogens, a solitary approach to research and communication is imperative in keeping track of the shared diseases. Similarly, many of our health related issues such as the anti-microbial resistance, food sustainability, chemical pollution, etc. span multiple disciplines, and thus require a collaborative solution.

Although the foundations of the One-Health concept originated within the veterinary and human medical professions, there is a strong push towards making it a multidisciplinary network. The One-Health concept has also been endorsed by the United Nations.

A tripartite collaboration comprising the Food and Agriculture Organization, WHO and OIE has published a concept note for sharing responsibilities and coordinating global activities to address health risks at the animal-human-ecosystems interfaces.

Thus, all human health care practitioners, veterinarians, public health and environmental health professionals should consider the ‘One-Health’ approach as a professional imperative for the shared interests of healthy co-existence of all the living beings.