One Health: A Unified Approach to Protecting the Health of People, Animals, and the Planet
By Zachary Liebowitz | September 19th, 2024
In recent years, the concept of One Health has emerged as a vital framework for addressing the intricate connections between human, animal, and environmental health. With growing recognition of how human activities impact ecosystems and a greater appreciation of the human-animal bond, this multidisciplinary approach seeks to create holistic solutions that improve health outcomes across the board.
At its core, the One Health framework is a collaborative and integrating strategy that recognizes the interdependence of the health of humans, animals, and the environment. The idea is that the well-being of one affects the others. For example, changes in the environment, such as deforestation or pollution, can disrupt wildlife ecosystems, leading to new zoonotic diseases that can jump from animals to humans, such as COVID-19 or Ebola.
One Health recognizes that health issues cannot be adequately addressed in isolation. Bringing together veterinarians, physicians, environmental scientists, policymakers, and public health experts is the best way to identify and mitigate shared risks at their sources. This approach is especially critical in today’s interconnected world, where the boundaries between animal, human, and environmental health are increasingly blurred.
One Health and Toxicology: A Natural Fit
Environmental pollutants like pesticides, heavy metals, and endocrine-disrupting chemicals don’t just affect one species—they can have ripple effects across ecosystems. These pollutants can accumulate in animals, make their way into human food systems, and eventually contribute to chronic diseases in humans, such as cancer or neurological disorders.
For example, consider the widespread use of neonicotinoid pesticides, which have been linked to declining bee populations. This decline doesn’t just affect pollinators. It also threatens food security by disrupting the agricultural systems that depend on them. Similarly, persistent organic pollutants like polychlorinated biphenyls accumulate in the environment, leading to adverse health effects in both wildlife and humans, often through contaminated water and food sources.
The One Health framework encourages the integration of toxicological data into larger discussions about environmental policy, wildlife conservation, and human health interventions. By doing so, it supports more effective and sustainable approaches to managing the complex, interlinked threats posed by pollutants.
Zoonotic Diseases: The Human-Animal Health Interface
One of the most pressing areas where the One Health framework demonstrates its value is in the prevention and control of zoonotic diseases—those that spread between animals and humans. The majority of emerging infectious diseases, including some of the most notorious such as HIV/AIDS, influenza, and the more recent SARS-CoV-2 (the virus responsible for COVID-19), originated in animals.
Traditional public health strategies focus on human populations, which means that they miss early signals of emerging diseases in animal populations. By adopting a One Health approach, researchers and policymakers can better monitor and control zoonotic diseases before they spread to humans. This requires close cooperation between veterinarians, ecologists, epidemiologists, and public health officials to detect, track, and respond to outbreaks early.
Additionally, the emergence of antimicrobial resistance as a serious human health issue highlights the need for a One Health approach. The overuse of antibiotics in both human medicine and animal agriculture has accelerated the development of bacteria that are resistant to many antibiotics. These superbugs can spread across species and environments, posing an urgent global health crisis. Only by addressing antibiotic use holistically—across human healthcare, animal farming, and environmental management—can we hope to curb this threat.
Climate Change and One Health: A Global Challenge
Combatting climate change offers and opportunity to employ the One Health approach to address critical problems.. Rising global temperatures, shifting weather patterns, and extreme climate events are altering ecosystems and habitats. These changes can affect vector-borne diseases such as malaria and Lyme disease by expanding the habitats of mosquitoes and ticks into new regions. Similarly, warmer waters can increase the spread of harmful algal blooms, which produce toxins that impact marine life and contaminate seafood consumed by humans.
In this context, One Health provides a necessary framework for understanding how climate change impacts the environment, as well as the health of all species. By recognizing the interconnectedness of these systems, scientists and policymakers can develop more effective strategies for mitigating and adapting to the health risks posed by climate change.
A Path Forward
The One Health approach offers a powerful tool for tackling the complex, interrelated health challenges of the 21st century. As we face global issues such as climate change, zoonotic diseases, and environmental pollution, adopting a collaborative and interdisciplinary mindset and embracing One Health is essential. By recognizing the interconnectedness of human, animal, and environmental health, One Health not only provides a roadmap for more effective disease prevention and health promotion but also helps build a more sustainable and resilient future for all species.
In the end, the health of the planet is the health of all its inhabitants—human and animal alike—and One Health offers the best opportunity to safeguard both.
The views expressed do not necessarily reflect the official policy or position of Johns Hopkins University or Johns Hopkins Bloomberg School of Public Health.
