Expert Speak Health Express
Published on Aug 02, 2024

A holistic One Health approach is crucial for tackling zoonotic diseases, focusing on prevention, collaboration, and innovation for better health security

Incorporating “One Health” into the health-security agenda

The recurrence of the deadly Nipah virus has placed India on high alert and is indicative of the urgent need to understand health security with an ecological perspective. The One Health strategy emphasises on “an integrated, unifying approach that aims to sustainably balance and optimise the health of people, animals, and ecosystems. It recognises the health of humans, domestic and wild animals, plants, and the wider environment (including ecosystems) are closely linked and interdependent.” It aims to bring to the foray a multidisciplinary dimension to health security with a key emphasis on the interdependence and interconnectedness between humans, animals, and the environment. While policymakers and international organisations promote One Health, in reality, however, there exists a gap between theory and practice. 

One Health strategy 

Studies from the COVID-19 pandemic demonstrate that the global health response prioritised virus containment strategies, in the form of social distancing and mask mandates, and increased resource allocation towards the production of vaccines and antivirals. While these measures were beneficial, the responses have failed to determine the causative factors of the pandemic, which lay at the heart of the human-animal-environment interface. For instance, early warning and surveillance systems, and multidisciplinary stakeholder collaboration would have provided clarity on the mechanism of SARS-CoV2 emergence and little attention would have been devoted to speculative analyses on the origin of COVID-19. Accordingly, to prevent and limit the outbreak of future zoonotic diseases the health security agenda needs to incorporate a One Health strategy by focusing on the factors that cause viral pathogens to cross the species barrier. This can be achieved through the Pandemic Fund, a mechanism to operationalise a One Health approach by strengthening India’s animal health security towards pandemic preparedness. This will enable the identification and implementation of actions that control the risk of cross-species transmission and would thus form a crucial step in the preparedness for the next epidemic or pandemic. 

Studies from the COVID-19 pandemic demonstrate that the global health response prioritised virus containment strategies, in the form of social distancing and mask mandates, and increased resource allocation towards the production of vaccines and antivirals.

The story of Nipah 

The ongoing Nipah virus outbreak in Kerala is an ideal example of a devastating zoonotic disease with global implications that necessitates the inclusion of a One Health approach to health security. Nipah virus is a highly pathogenic zoonotic virus that is considered by the WHO as a global threat with epidemic potential. The virus displays high mortality in humans and no vaccine is currently available. The first reported outbreak in humans occurred in Malaysia in 1998 and since then, south and southeast Asia have been identified as regions that are highly prone to outbreaks. India has witnessed more than six outbreaks since 2001, with a majority of the outbreaks occurring in Kerala. Human infection is typically acquired from direct contact with secretions from Nipah virus’s natural reservoir, the fruit bat (genus Pteropus), consumption or contact with virus-contaminated fruit products, or direct human-human contact. Infections acquired from pigs, an intermediate host of the Nipah virus, were reported in cases identified in Malaysia and Singapore. 

The first reported outbreak in humans occurred in Malaysia in 1998 and since then, south and southeast Asia have been identified as regions that are highly prone to outbreaks.

Technical input and funding from the WHO have enabled Kerala to respond rapidly to the recent outbreaks through stringent public health responses in form of social distancing, mask mandates, containment strategies, and curfews. These responses are adept at preventing further human-human transmission and are beneficial once the virus has spread within the human population. In addition, for the Nipah virus, and for the vast majority of zoonotic diseases, medical treatment is limited as therapeutic interventions may be restricted to emergency use or may not be fully licensed. Taking into consideration the lack of vaccines and therapeutics, the extreme containment strategies employed, and Nipah’s epidemic potential, there is a critical need to adopt preventative strategies before an outbreak ensues. 

An inclusive strategy 

An ideal surveillance system that is capable of providing information on probable outbreaks would involve surveillance and detection of the Nipah virus within its ecosystem, discernment of possible intermediate hosts, and identification of causative factors that trigger viral spillover events. Viral spillover events or crossing of a viral pathogen from animals to humans is the major cause of disease outbreaks in humans but health security frameworks seldom incorporate strategies to identify its causative factors. 

Viral spillover events or crossing of a viral pathogen from animals to humans is the major cause of disease outbreaks in humans but health security frameworks seldom incorporate strategies to identify its causative factors. 

In the case of the Nipah virus, studies indicate that anthropogenic activities alter the ecology of bats and trigger spillover events. Activities including, deforestation, dense human settlements around bat-populated areas, and urbanisation have contributed to changes in the bat ecosystem. Resultantly, these changes alter the roosting and feeding habitats of bats and their viral shedding habits. Land degradation and deforestation, for example, have generated more human-populated habitats, and these events are likely to cause bats to interact frequently with humans. Secondly, these kinds of stressors impact viral shedding activities and can cause enhanced shedding (and thus, chances of infection) in human-dominated areas. In a similar vein, there may be additional factors, anthropogenic or other evolutionary drivers that contribute to spillover events. A One Health approach would entail monitoring bat populations and habitat preferences using remote sensing, Geographic Information System (GIS), and AI tools. These analyses can provide a robust assessment of the drivers of spillover events. Identification of these factors can lead to behavioural actions, such as, modification of ecosystems to diminish the probability of spillover events, adoption of steps to minimise contact with bats during particular seasons, and implementation of alternative farming practices, which can ultimately aid in preventing future outbreaks. 

Existing One Health initiatives 

A strategic partnership between the international organisations, the Quadripartite—the Food and Agriculture Organisation of the United Nations (FAO), the United Nations Environment Programme (UNEP), the World Health Organisation (WHO), and the World Organisation for Animal Health (WOAH)—advance One Health initiatives and have launched the One Health Joint Plan of Action, which addresses mechanisms to bolster the capacity to respond to emerging challenges at regional, national, and global levels. Similarly, the United States (US) and the United Kingdom (UK) have adopted a One Health approach with the USA’s Centers for Disease Control and Prevention (CDC) advancing the Global Health Security Agenda through coordinated surveillance support to global partners, while the UK One Health endeavour centres on antimicrobial resistance and its spread between food, humans, animals, and the environment. Regional neighbours, China and Brazil, have directed One Health efforts by developing health infrastructure under the Belt and Road Initiative and by surveilling vector-borne diseases, respectively. India’s National One Health Mission recently convened its inaugural executive committee meeting with emphasis placed on “integrated disease control,” while The Centre for One Health under the National Centre for Disease Control is actively involved in collaborations with stakeholders for controlling zoonotic diseases.  

Looking ahead 

A holistic approach that considers the human-animal-ecosystem interface is needed to tackle emerging zoonotic infectious diseases. The adoption of preventative strategies is by far the greatest tool at our disposal but it requires an integration of a One Health approach to the health security agenda to determine what causative agents trigger viral outbreaks in the human population. Collaborative efforts through the Quadripartite, regional neighbours, and national projects can strengthen the approach to combating emerging infectious diseases. Sharing of real-time information and resources, and the development of innovative technologies for surveillance and control will be valuable. The adoption of a pragmatic approach to health security, where there not only exists a reactive machinery to combat public health crises, but elaborate efforts to develop preventative measures against infectious disease is a pressing priority. India can take this opportunity to champion the integration of a One Health approach to addressing future health challenges.  


Lakshmy Ramakrishnan is an Associate Fellow at the Observer Research Foundation.

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Author

Lakshmy Ramakrishnan

Lakshmy Ramakrishnan

Lakshmy is an Associate Fellow with ORF’s Centre for New Economic Diplomacy.  Her work focuses on the intersection of biotechnology, health, and international relations, with a ...

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