One Health – The importance of rationalising what always was

One Health – The importance of rationalising what always was

Attempting a definition 

Health – today recognised as a right by most countries, is ironically difficult to define. While the World Health Organisation invokes numerous aspects of health such as physical, mental and social; other definitions consider spectrality in health, still others offer an operational definition for health. Despite these variations, that health is a potentiality that allows one’s life to be cherished has been accepted – authors and governments across ages have explored the numerous connotations of health. ‘One Health’ is a concept that compounds this acceptance, purporting that the health of all living things should be considered together. Various bodies have undertaken the laborious process of defining One Health. The Centers for Disease Control definition incorporates collaboration and multi-sectorality; the One Health Global Network definition emphasizes the interconnectedness of humans, animals and plants. For the purpose of this exposition, One Health is operationally summarised as a united approach to the health of all living things. 

Some Illustrations 

The prospect of One Health is best understood by case study. 

For instance, antimicrobial abuse in livestock leads to antimicrobial resistance in animal-affecting bacteria; studies have shown that in case of these bacteria infecting human beings, this predilection is carried forth. This has deeper implications – the livestock industry, including the harvest of produce, already contributes disproportionately to the carbon footprint; bio-economics studies the conversion of sunlight into energy by biological systems and attempts to draw parallels with economical models. In such analyses, antimicrobial resistance in animals worsens what is already a less than optimal process, for antimicrobial resistance is associated with increased treatment and research costs. Food security, another fundamental right, is practically inseparable from health – as evidenced by the Sustainable Development Goals; although antimicrobials may be employed in livestock to further food security.

Another example drawing out the inter-linked nature of health systems is the case of the West Nile Virus. The virus affects avian as well as human populations, but the seasonal propensities of the virus varies between these two populations. Early-season West Nile Virus associated avian mortality is a signal of an incoming human infection, a phenomenon that epidemiologists have attempted to monitor. The underlying concept is that those factors that promote spread within humans also tend to do so within birds; therefore, an integrated approach is of the essence. Contamination of water sources - by bacteria and chemicals - leads to poisoning of all living beings using those sources. Special consideration must be given to biomagnification, a phenomenon which occurs when a pollutant cannot be excreted by biological systems. For instance, mercury ascends the food chain, from fish to human beings, increasing in quantity. Environment monitor programmes thus track biological oxygen demand, an indicator of bacteria in water, along with the amount of chemical pollutants - a potent illustration of how indicators of ecosystem health point also describe human health; in other words, common indicators of health - impelling to thought the concept of One Health. 

Zoonoses 

Zoonoses are a unique case study; pathogens do not consider species boundaries, jumping across them regularly. Whereas some parasites such as Taenia solium affect different species at different points in their lifecycle, some bacteria and viruses can infect multiple species simultaneously. The Japanese Encephalitis virus underlines the latter principle - it infects Ardeid birds, such as herons but amplifies itself in pigs, before infecting human beings, with Culex mosquitoes facilitating transmission. Japanese Encephalitis control programmes, thus, tend to be multi-pronged with vaccination, anti-mosquito and animal host control angles. Sanitary measures for Taenia solium and Japanese encephalitis infection base themselves on the realization that better sanitation in the pig population leads to decreased infection in human beings. Analytically, control measures in the animal populace lead to outcomes in the human populace, a strong case for why health should be looked at holistically. 

Respiratory viruses, such as some species of influenza, are interesting in that they undergo mutations - reassortment and rearrangement - in a variety of hosts, including humans, pigs and birds. Very often, pigs act as mixing vessels, facilitating the genesis of new strains -

strains which tend to spread rapidly owing their expression of previously non-existent antigens. Drawing from these principles, regional governments initiate control programmes, including butcher shops and other sites of man-animal interaction. Other zoonotic diseases such as COVID-19 and Ebola have been attributed to wet markets and bushmeat harvesting - practices that are unregulated and often unsanitary; this points towards one direction - excellent animal health is essential for excellent human health. 

A special example is Rabies, spreading primarily through the bite of infected dogs, public health specialists have resorted to dog vaccination and sterilization as preventive techniques. 

Ecology 

Ecological studies have always considered humans in the context of the environment. Nature bears no prejudices towards social boundaries, indiscriminately engaging all entities, living and non-living. Ecologically, an organism is not an isolated system; but rather, a part of a whole. A situation which is 'healthy' for an infectious bacterium is not so for its host. Biodiversity, now encompassing bacteria, protozoa and fungi, in addition to plants and animals is ecologically a marker of health. Tangentially, the gut microbiome holds a host of interesting truths. Metabolic syndrome, malnutrition and mental health are all influenced by the metabolic activity of the gut microbiome. Further, the microbiota aid in digestion and supplement the mucosal immune system; antiobiotic abuse alters this delicate balance such that both the host and the commensals lose out. Climate change too factors into the equation. Warmer climates drives many sub-tropical countries into a tropical weather ecosystem, boosted by unpredictable torrential rainfall. This enables the breeding of insect vectors, such as flies and mosquitoes, augmenting a cycle of poor health. Further, studies have shown permafrost to contain genetic material of pathogens from past ages, potential triggers of pandemics. Finally, encroachment upon wilderland and deforestation, disturbs the ecological balance of an area, driving mass animal migrations and provoking unfavourable human-animal interactions; repercussions range from zoonotic diseases to physical conflict. The former is exemplified by the Kyasanur Forest Disease outbreaks in Karnatka which were set off by the felling of trees to promote mining. 

One Health allows us to circumvent these apparent contradictions, a healthy ecosystem is one where biological processes, chiefly photosynthesis and reproduction, take place uninhibited.

From this point of view, the goals of health and environment conservation align themselves. One Health is an opportunity for us to re-envisage human-nature interactions. Human endeavours are in many ways shaped by an anthropocentric (human centred) tinge. By placing the Planet at the forefront, and man, animals, plants and all other living things as its organs, human activities will be looked at in a new, ecologically sustainable angle. 

Evolutionary analysis 

Extending the above arguments, species have been through evolutionary pressures, morphed into more efficient versions of themselves. Efficiency, here, means better success at scouring for food and mating. From a Darwinian perspective, the elimination of one species in an ecosystem, or its poor health translates into weaker selective pressures, causing the health of all organisms to decline. A forest fire, producing a clearing by eliminating vegetation, makes it easier for predators such as eagles to capture prey like rats, the resultant decline in the rodent population and the succeeding increase in the eagle population, will cause food chain collapse. Tropical regions, with more sunlight, trap more energy, have more luscious environments and hence more biodiversity. At the same time, polar regions, immersed in ice-caps, have tenacious organisms like polar bears and seals that are highly efficient in sequestering energy. The pervading theme throughout these expositions, is that the health of organisms cannot be considered in isolation. 

Food Security 

Food sourcing is where the concept of One Health becomes most evident. The various kinds of interspecies relationships such as mutualism, parasitism and commensalism are almost always based on food. Parasites having poor digestive systems, depend on complex organisms for nutrients; Mycorrhizal fungi transfer nutrients to trees which then convert them into substrates, enabling the fungi to utilize them. However, there is another angle to this relationship. The recent locust attacks on farmlands in Northern India, indicate a stark underlying reality. Resources are always limited and living things must compete for them. The Irish potato famine, the inspiration for many a sad melancholy, was set off by fungi infecting potatoes and triggered the death of millions. Still, these observations needn't be treated as excluding of One Health. Considering that organisms are the food sources of other

organisms and that some conflict promotes life (philosophically as well!), the archetypal food cycle evidences One Health. 

Economy 

Some consideration must be given to economical networks. Livestock and plant produce, figments of food security are , financially, units of trade. Any break in the supply chains of these products will threaten supply chains of many food and related industries. Yet, this argument shouldn't be seen as demeaning of the health of plants and animals. That our lives are ever connected must impel us to rationalize our mutual dependance, and reconcile any disparities. With globalisation promoting the interconnectedness of human beings, it is prime that we consider its repercussions - the loss of forest cover as we and the objectification of other living things. 

Culture 

Excitingly, globalisation itself holds the key to this problem. Cultures have always held that all living things are manifestations of the divine. Literary classics such as Valmiki's 'Ramayana' and Shakespeare's 'As You Like It', have used dead animals and fading plants as metaphors for death and privation - in the eyes of society's greats One Health was always the norm. It would seem that separating health is inorganic and unwise as well. In thousands of years of civilization, humans and animals have formed and sanctified a bond that ensues not only interdependence but a universal family - the Indian Concept of the Vasudeva Kutumbakam. Literally translating to 'the family of the lord indwelling in all souls (atmas)', this motif lays importance on the common divinity of all sentient beings. When defining health, respect was given to its role in promoting the enjoyment of life and its place as a right; the concept of the universal family upholds this principle as a guiding light for all living things. 

Concluding remarks 

While One Health is certainly a reality, there remains the question of actualization. How do we synthesise this concept into action? The wise have always upheld that all thought that doesn't lead to action is betrayal. This essay cannot hope to address such a gargatuan question

- still, in the process of surmising One Health some points have become evident. Firstly, One Health is a joint endeavour - it must encompass people from all walks of life - the citizenry, medical professionals - both human and animal, farmers, health workers and researchers. Secondly, the levels of prevention hold true for One Health as well. Efforts must be directed towards primary prevention with surveillance, control and investigation for this is the most sustainable, wholesome and benefitting. As for a unified One Health System, akin to the NHS in the UK - considering the potentiality of life for each living thing empathetically, addressing their health to be as valuable as ours should be the only way forward. No one knows what the future holds for our planet, but with this principle in mind, life presently on Earth becomes a fruit to be cherished . From this point of view, One Health is indeed a dire need.