Collaborative Health Practices

Implementing a comprehensive health philosophy necessitates collaboration among veterinarians, physicians, environmental health specialists, wildlife experts, and social scientists.

Beyond human collaboration, addressing global health challenges requires combining methodologies and insights from the three One Health sectors into a unified strategy.

The necessity for such a multidisciplinary approach is encapsulated in the words of veterinarian Adam Little: “Compartmentalization of knowledge inhibits progress. Only through collaborative efforts can we properly analyze and tackle the complex health issues society faces today.”

Numerous initiatives, programs, legislative proposals, and research endeavors are working to enhance this interdisciplinary collaboration. Examples include the One Health Initiative, the European One Health Action Plan against Antimicrobial Resistance, a course at Massey University linking biosecurity with health, the One Health Network in South Asia, and the Netherlands Centre for One Health.

Let’s explore how these concepts apply to a specific health issue.

Understanding Japanese Encephalitis

Japanese encephalitis (JE) is a viral inflammation of the brain caused by a flavivirus, part of the same family that includes Zika, dengue, and yellow fever viruses.

This disease is primarily found in Southeast Asia, with 87% of reported human cases from 2011 to 2015 originating in India, Nepal, China, and Vietnam. Children and young adolescents are particularly vulnerable, making JE a leading cause of viral encephalitis in this region.

Most individuals infected show few to no symptoms, but those who do exhibit symptoms face a fatality rate of up to 30%. While there is no antiviral treatment available, vaccinations can prevent future infections.

#### The Intersection of Animal, Ecosystem, and Human Health

The JE virus (JEV) is mainly transmitted to humans and horses through mosquitoes, particularly the Culex tritaeniorhynchus, which acquires the virus by feeding on infected pigs. Other hosts include water birds, chickens, bats, pigeons, reptiles, amphibians, and ducks.

JEV thrives in warm, rainy seasons in temperate regions and persists year-round in tropical climates, often in rice cultivation areas.

For instance, the black-crowned night heron, a water bird, plays a role in spreading the virus due to its migratory behavior and its presence in rice fields.

The sensitivity of both animal and human health to climate and ecosystem changes is evident in various studies.

Researchers like Hui Zhang et al. note that changes in climate have allowed JEV to be detected at higher altitudes in Tibet, China. Similarly, Meghnath Dhimal et al. warn that climate change may increase the risk of JE epidemics in Nepal, correlating rising temperatures with higher incidence rates.

James Pearce et al. indicate that the virus's transmission is extending to northern latitudes, and Ioanna Lytra and Nikolaos Emmanouel found a significant population of Culex tritaeniorhynchus in Western Greece's rice fields.

Additionally, Philip Mellor and Colin Leake suggest that warmer temperatures may enable less efficient JEV carriers to become primary transmitters, potentially broadening the virus's geographical distribution.

Furthermore, Mukhtor Turaev illustrates that the black-crowned night heron can migrate beyond its usual range while adapting to human environments under ecological pressures.

Increased meat production in Asia, particularly pork, chicken, and duck, along with a shift from rural agriculture to large-scale livestock farming, places more potential JEV hosts in proximity to humans, increasing infection chances.

Urbanization trends also contribute, as more individuals move to peri-urban areas and engage in urban animal husbandry for economic survival.

Despite typically being associated with rural settings, the risks of JEV transmission and incidence cannot be overlooked in urban environments.

Indeed, JEV has been detected in pigs in Can Tho city, Vietnam, and in multiple human cases across several major Asian cities.

Collaborative One Health Strategies

Having explored the interdependence of the One Health components, how does a One Health approach manifest in the case of JE?

One example can be found in Papua New Guinea (PNG), where a multi-partner initiative funded by the Australian government aimed to enhance surveillance and response systems for quicker identification and containment of JE from February 2019 to June 2020. This project fostered partnerships between local public health and veterinary organizations.

In Bangladesh, while humans are typically vaccinated against JE, a One Health project funded by Grand Challenges Canada from March 2014 to September 2015 focused on vaccinating pigs to reduce transmission risks to humans. This was a practical and cost-effective approach due to the area's small pig population.

Finally, in Cambodia, Laos, Vietnam, and Myanmar, a project supported by Institut Pasteur (IP) aims to build a comprehensive understanding of JE pathogens while enhancing hospital capacities for diagnosis and care. This initiative integrates environmental, epidemiological, and sociological analyses with surveillance and outbreak investigation methodologies.

According to researchers involved in the IP project, recognizing our interconnectedness and the threats posed by disease transmission can significantly enhance our understanding of JE epidemiology.

The Future of One Health

In light of the ongoing challenges posed by the SARS-CoV-2 virus, many around the globe have long advocated for stronger collaboration between animal and human health sectors.

The changes in climate and ecosystems over recent decades—particularly their impacts on both human and animal well-being—are increasingly difficult to ignore.

As we begin to grasp the intricate connections between the natural environment, humans, and animals, it becomes clearer that the One Health concept merits significant attention in its own right.