In recent years, environmental hazards, unprecedented scale of economic and industrial growth, changing face of societies world over and emergence of new and old infectious diseases have forced man to acknowledge the interdependency of the fate of the planet in general and human societies in particular. The research community has responded by developing an ecosystem approach to human health or EcoHealth to come up with a more contemporary and relevant way of addressing these present day issues that impact the environment and those living within its confines, namely animals, humans and livestock. The main principles on which the concept of EcoHealth rests includes trans-disciplinarily, systems thinking, multi-stakeholder participation, equity, environmental sustainability and evidence for community-based interventions.
EcoHealth, which evolved in the mid-1990s as a paradigm conceived by the International Development Research Centre (IDRC) scientists to better understand linkages between nature, society and health, was introduced in Southeast Asia in the mid-2000’s immediately after the SARS and avian influenza outbreaks. This was followed by the setting up of theAsia Partnership on Emerging Infectious Diseases Research (APEIR) in 2006, focusing actively on Cambodia, China, Lao PDR, Indonesia, Thailand and Vietnam. Since then, a comparatively expansive portfolio of activities has been stimulated, especially over the last decade.
EcoHealth’s focus on Southeast Asia
The impact of rapid pace of agricultural and livestock intensification is having a profound impact on ecosystems and human health. In Southeast Asia particularly, given the intensive use of chemical fertilisers, pesticides and irrigation technology, in combination with high-yielding crop varieties, there is intense pressure on the environment and its natural resources. To address some of these concerns, integrative approaches of EcoHealth and the closely related One Health have come to be viewed as highly attractive concepts, duly endorsed by the WHO, FAO and OIE.There is growing consensus amongst them to generate evidence that can strengthen understanding of the dependence of health on ecosystems, as well as establish a need to widen EcoHealth approaches that can address the interconnected and up-stream drivers of health and well-being: environmental, social and economic factors.
Adopting the EcoHealth approach to a JE study in North India
The EcoHealth movement has been gaining greater momentum in India and within RCZI’s own initial work too. While embarking on the study, “Identifying Sources, Pathways and Risk Drivers in Ecosystems of Japanese Encephalitis in an Epidemic-Prone North Indian District”, in 2013, a group of researchers at RCZI came together as “EcoHealth Research Core Group” (ERCG) to adopt EcoHealth’s knowledge-to-action framework to guide the study. JE causes frequent seasonal outbreaks in rural India with high morbidity and mortality in children, specifically in eastern Uttar Pradesh, where transmission patterns and risk drivers remain under-explored. Despite repeated outbreaks of JE, limited information exists on these risk drivers.
Following a trans disciplinary methodology and study protocol, RCZI conducted the study in three blocks of Kushinagar district. The EcoHealth approach which was duly backed by a multidisciplinary team of investigators, helped shape a framework for collecting and managing data points from different disciplines in a single research study providing insights into disease causation from a multidimensional perspective while generating knowledge that is actionable, acceptable, relevant and feasible. From this emerged inputs for recommendations and policies based on a comprehensive understanding of disease ecology.
Emphasising a unique, inter sectoral approach to understand JE transmission, it studied the association of ecological, physical, biological and social factors on transmission of JE virus among different host populations in Kushinagar. Given the strong EcoHealth focus of the study, the core group that comprised of an epidemiologist, entomologist, veterinary public health specialist and a virologist with a public health background. The institutional partners were rechristened as the ERCG. Together, they lookedatsocio-cultural dynamics which can strongly influence disease transmission and outcomes. The team was able to identify a set of integrated research questions as also integrate research questions arising from sector-specific knowledge gaps. In doing so, they made use of a range of methods, such as household surveys, focus group discussions, in-depth interviews, virus detection in humans, pigs and mosquitoes and geospatial analysis. This integration of research questions adhered to principles of EcoHealth research and generation of evidence-based recommendations for policymakers.
A participatory approach ensured that stakeholders, moreso local communities, were engaged at all stages of the study, generating knowledge that was actionable. The multidisciplinary team of researchers adhered to the trans disciplinary approach from the stage of developing an integrated conceptual framework that focused on JE from the perspective of a biotope and not from the perspective of disease or discipline, thus transcending disciplinary silos. The mixed methods approach with a strong qualitative component was then used to establish a more sound understanding of local factors, making recommendations socially and environmentally sustainable.
Overcoming some of the challenges of the Ecohealth approach
The trans disciplinary approach led to identification of key knowledge gaps and generation of important hypothesis for future enquiries. However, the broad base of EcoHealth which at times chooses ‘breadth’of enquiry over ‘depth’ was seen as challenge. For example, a more meaningful understanding of local ecology and its implications on vector bionomics would have been possible through a longitudinal study involving multiple rounds of vector collections over different years and eco-zones. Similarly, presence of viral RNA in the blood of healthy children merits studying its clinical and public health significance over time. The linkages between changing agricultural practices, ecological developments, social inequities with disease transmission and health seeking is another issue that has important significance and which needs to be studied in greater detail.
The study concluded with findings that reinforced the relevance of the EcoHealth perspective to studying JE in Uttar Pradesh. Going forward, this could be used to form the basis for an interdisciplinary approach to addressing not just JE but also other diseases that overlap the human-animal-environment interface.
Charron DF: Ecohealth research in practice innovative applications of an ecosystem approach to health. Ottawa: Springer; 2012.
Henry A, Ellis B, Kapan D, Krend K, Bennett S, Wilcox BA: Technical notes and exercises for ecosystem characterization with reference to aedes vectors of dengue: developed for the First Community of Practice (COP) workshop for research teams participating in the TDR/IDRC research initiative on eco-bio-social research in Asia. Bangkok: Center for Vectors and Vector Borne Diseases, Faculty of Public Health, Mahidol University; 2006.
JE outbreaks are being reported from previously unknown foci. Further, encephalitis outbreaks of other aetiologies in endemic areas have only added to their complexity. For programme managers, researchers and community health professionals, access to accurate and updated information is key to planning interventions and other relief measures.read more