ONE HEALTH

One World One Health: Prevent Zoonoses

August 5, 2024

One World One Health: Prevent Zoonoses

Sanjiv Kumar and Ritesh Patel

Department of Veterinary Pathology

Bihar Veterinary College, BASU, Patna-14

Introduction

The concept of “One World, One Health” recognizes the inseparable nature of humans, animals, and the environment. It highlights the immediate awareness of the relationship between ecology, veterinary diseases and public health, emphasizing the need to restore and maintain harmony and unity. A One Health approach can provide more comprehensive information on infection prevention compared to traditional environmental methods.

Any disease that is naturally transmissible from animals to humans or from humans to animals are classified as zoonotic disease. Zoonotic diseases can be caused by a number of pathogenic agents including viruses, bacteria and parasites. Interactions between animals, environment and humans play a significant role in the emergence and transmission of various zoonotic diseases. Most of these infectious diseases affecting humans originate from animals. These are directly transmitted from animals to humans or indirectly via intermediate hosts such as mosquitoes and ticks. These diseases are responsible for huge toll annually. In addition to their detrimental effects on human health, zoonoses also adversely affect animal health and reduce livestock production. The report says that around 60% of emerging human infections are zoonotic in nature and most of them originate from wildlife species. Important examples are infectious diseases like Zika virus infection, West Nile Virus Disease, Brucellosis, Bovine Tuberculosis, Rabies, Ebola and Avian influenza. Globally, zoonotic diseases have the greatest impact in low and middle income countries.

The host-pathogen interactions are affected by a wide range of environmental factors, thus illustrating the increasing need for collaboration to address zoonoses and contribute towards overall human health considering animal health as well as environmental quality. Therefore, the need for scientific methods to address today’s health and environmental challenges has never been more urgent. The One Health approach leverages the expertise of researchers from various local, national, and international disciplines, including public health and medical professionals, to tackle issues common to human, animal and environmental health. While the need for multidisciplinary research is not new, the OH concept has gained momentum. Researchers in human medicine, public health, veterinary medicine, urban planning, and environmental sciences are increasingly seeking holistic, integrated solutions to complex health problems affecting humans, animals, and the environment.

Background

The One Health System originated in the 19th century when Rudolf Virchow (1821-1902) integrated veterinary medicine into the field of human health, asserting that there was no distinction between the two. This idea set the stage for the global rise of the One Health Strategy, which gained significant momentum in the early 2000s. Since then, collaborative efforts have continued to expand. In 2008, four international organizations— the Food and Agriculture Organization of the United Nations (FAO), the World Organisation for Animal Health (OIE), the World Health Organization (WHO), and UNICEF—along with the World Bank and the United Nations Influenza System Coordinator, produced a policy report titled “One World, One Health: Safety for Safety System Interface.” A significant milestone for the One Health platform was the World Veterinary Medical Association (WVA) and World Medical Association (WMA) World Health Conference in May 2015. This conference proposed a collaborative partnership between veterinarians and doctors to improve both animal and human health. Since then, the One Health concept has gained widespread recognition, and its initiatives have grown rapidly.

Importance

To prevent and control infectious diseases, particularly zoonotic diseases, international organizations and researchers have described the interconnectedness of humans, animals, and the environment, adopting a concept known as the “One Health Concept” or “One Health Approach.” This concept aims to address global health challenges effectively. The One Health approach fosters collaboration among wildlife biologists, veterinarians, physicians, agriculturists, ecologists, microbiologists, epidemiologists, and biomedical engineers to ensure the health of animals, humans, and the environment.

The One Health approach has significant impacts on poverty alleviation, food security, and health security, especially in developing countries, through the prevention and control of zoonoses. According to Pieracci et al., the One Health approach recommends several strategies for preventing and controlling zoonotic diseases like improve coordination between human and animal health agencies, creating a national strategy, adopting veterinary public health policies in collaboration with other countries and regularly reviewing zoonotic diseases every 2-5 years to address emerging and re-emerging diseases through continuous surveillance and laboratory diagnostics. This approach supports zoonotic disease prevention and control efforts and enables effective and inclusive public health emergency planning. Overall, the One Health Initiative promotes global health security by addressing health problems such as zoonotic diseases, vaccine development, and food safety and security through coordinated projects and information exchange.

One health approach for the control of zoonotic disease

Zoonoses dynamics involve two key interfaces: the human-animal interface and the human-environment interface. Many diseases persist at low levels in animals within their habitats but can spread to humans due to factors such as deforestation, climate change, and habitat disruption. During this process, pathogens can mutate and cross species barriers, infecting humans and other species. The recent coronavirus outbreak is a prime example of a virus jumping from animals to humans and evolving into new variants. International travel and diverse human movements have also contributed to the rapid spread of COVID-19, making it a global pandemic. Implementing the One Health global initiative is essential to protect human and animal health by controlling toxic chemicals and waste, preserving biodiversity, and maintaining ecosystem balance. This approach can help prevent future disease outbreaks.

To identify new viruses with the potential to infect humans, the development and integration of surveillance and monitoring methods are crucial. Controlling hotspots, such as the livestock trade, is necessary to prevent disease transmission between animals and humans. Policies and programs should address infection risks among vulnerable groups and healthcare workers. Cooperation among all stakeholders is vital for the effective implementation of One Health principles and policies.

Experts from the CDC’s One Health Office have proposed strategies in the One Health Zoonotic Disease Prioritization to prevent and control zoonotic diseases. Their recommendations include listing of emerging and re-emerging zoonotic diseases, implementing measures to reduce the spread, strengthening One Health coordination programs and generating reports on zoonotic diseases at national, subnational, and regional levels.

Prevention of Public Health Problems through the One Health Approach

The FAO/WHO/OIE document outlines several critical aspects of animal welfare and public health to effectively implement the One Health approach:

Compliance with International Standards: Adhering to international agreements and standards ensures that practices align with globally accepted guidelines, enhancing overall health security.
Continuous Biosecurity Evaluation and Improvement: Regular evaluation and improvement of biosecurity measures are required to prevent the spread of infectious diseases among animals and from animals to humans.
Legal Framework for Incentives: Developing a legal framework that provides incentives for cooperation with the private sector can enhance resource mobilization and encourage collaborative efforts in health initiatives.
Infrastructure and Expertise: Ensuring the availability of adequate infrastructure and expertise at both national and regional levels is crucial.
Laboratory Capacity and Capability: Adequate laboratory capacity, supported by external quality assurance systems, is essential for accurate diagnosis and research.
Timely Identification and Response: There must be systems in place for the prompt identification and response to health issues affecting both animals and humans.
Emergency Preparedness and Response Plan: Maintaining an up-to-date emergency preparedness and response plan is vital. This plan should outline procedures for addressing potential health crises promptly and effectively.
Monitoring and Evaluation of Health Services: Establishing systems for the continuous monitoring and evaluation of veterinary and public health services helps in assessing their effectiveness and identifying areas for improvement.
Risk Communication: The ability to communicate risk levels accurately to the public and relevant stakeholders is necessary for effective management and prevention of health threats.
Management and Legislation: Effective management and legislation should comply with international standards, ensuring that health policies and practices meet global benchmarks.

By implementing these measures, the One Health approach aims to create a comprehensive system that effectively prevents and manages public health problems. This integrated strategy not only addresses immediate health concerns but also builds resilience against future health threats. The collaboration between various sectors, supported by robust infrastructure, legislation, and continuous evaluation, ensures a holistic response to health challenges at the intersection of human, animal, and environmental health.

Conclusion

Most human infectious diseases originate from animals, posing significant threats to human health. Factors such as altered food habits, climate change, and environmentally harmful human activities contribute to the emergence and reemergence of many zoonotic diseases by increasing contact between humans and wild animals. The devastating impact of zoonoses on human populations is exemplified by the current COVID-19 pandemic. Given the strong interconnection among animals, humans, and the environment, it is crucial to prioritize research that focuses on the One Health approach to identify critical intervention steps in pathogen transmission. Implementing robust active surveillance that targets all components of the One Health approach is essential for the early and accurate detection of zoonoses, enabling the implementation of effective control measures.

References