One Health - Park's PSM (28th Edition)

Definition

• Endorsed jointly by WHO, FAO (Food and Agriculture Organization), and OIE (World Organisation for Animal Health)
• The 28th edition of Park's introduces One Health as an integrated framework acknowledging that human health cannot be separated from animal health and environmental health

The Triad of One Health

         HUMAN HEALTH
              /\
             /  \
            /    \
           /      \
ANIMAL HEALTH ---- ENVIRONMENTAL HEALTH

1. Human Health - medicine, public health, epidemiology
2. Animal Health - veterinary sciences, livestock and wildlife health
3. Environmental Health - ecosystems, climate, land use, water, biodiversity

Historical Background / Origin

Why One Health? - Key Facts

• >60% of all emerging infectious diseases in humans are zoonotic (originating from animals)
• 75% of new or emerging infectious diseases in humans are of animal origin
• >200 zoonotic diseases are recognized
• India has the largest livestock population in the world (~11% of global animal population) and 68.86% of population living in rural areas in close contact with animals - making zoonotic spillover a major risk

Important Zoonotic Diseases (Relevant to One Health)

• Anthrax, Brucellosis, Leptospirosis, Plague, Q fever, Tuberculosis, Ornithosis

• Rabies, Japanese encephalitis, Kyasanur Forest Disease (KFD), Monkeypox, Nipah, COVID-19, Avian Influenza (H5N1), Ebola

• Hydatid disease, Toxoplasmosis, Taeniasis/Cysticercosis

Classification of Zoonoses (Park's)

One Health - Drivers / Why Now?

1. Deforestation and habitat loss - brings wildlife into contact with humans/livestock
2. Intensive animal farming - facilitates disease amplification and AMR
3. Climate change - shifts vector distribution (e.g., dengue, malaria)
4. Globalization - rapid spread of pathogens across borders
5. Antimicrobial Resistance (AMR) - shared threat across human, animal, environmental sectors
6. Urbanization - increases human-animal-environment interface

Core Areas of One Health Action

1. Zoonotic disease prevention and control
2. Antimicrobial Resistance (AMR) - the most emphasized cross-cutting issue
3. Food safety and food systems
4. Vector-borne diseases
5. Environmental contamination and biosafety
6. Pandemic preparedness

One Health in India

• Launched under the Office of the Principal Scientific Adviser (PSA) and ICMR
• Goal: "To build an integrated disease control and pandemic preparedness system in India by bringing human, animal and environmental sectors together for better health outcomes, improved productivity and conservation of biodiversity"

• Largest livestock population globally
• High density of human-wildlife interface
• High zoonosis burden (brucellosis, leptospirosis, rabies, KFD)
• One of the largest consumers of antibiotics globally (AMR risk)
• Recent examples: COVID-19, Lumpy Skin Disease in cattle, Avian Influenza outbreaks

Control of Zoonoses - The One Health Framework

• Diagnosis, treatment, destruction (culling), quarantine, immunization of animal reservoirs

• Food hygiene, safety of animal products (wool, hides, meat, milk), proper disposal of animal carcasses, disinfection

• Immunization of high-risk groups
• Chemoprophylaxis
• Occupational health monitoring
• Health education
• Early diagnosis and treatment
• Environmental decontamination

One Health vs Related Concepts

Key Institutions in One Health

• WHO - Human health lead
• FAO - Food/animal health lead
• OIE/WOAH (World Organisation for Animal Health) - Animal health lead
• UNEP - Environmental lead
• OHHLEP (One Health High-Level Expert Panel) - Quadripartite body (WHO + FAO + WOAH + UNEP)
• NCDC, India - Coordinates zoonotic disease surveillance
• ICMR + NII + ICAR - Research coordination under National One Health Mission

Important One-Liners for Exams

• One Health = "One world, one health" - Interdependence of human, animal, environmental health
• The term "One Health" was popularized by William Karesh and Robert Cook (2004)
• Calvin Schwabe (1984) - "One Medicine" precursor

• 75% of emerging human infections are zoonotic

• AMR is the most important cross-cutting One Health challenge
• Quadripartite organizations = WHO + FAO + WOAH + UNEP
• India's One Health Mission is coordinated by PSA (Principal Scientific Adviser) office