11 - Key Concepts of One Health Flashcards
Traditional approach to infectious disease
- Human centric
- Only considers the implication of direct/immediate factors that impact on disease
- Addresses immediate issues but not risk factors
- More useful for direct transmission anthropopathic diseases
Miasma
Idea that diseases were caused by bad air
Black death
- Caused by Yersinia pestis
- Spread by flea vector harbored by rats in an environment exacerbated by human activity (poor hygiene. population density, travel
One health
- Interaction of human health, environmental health and animal health
- Full scope includes non infectious disease, vaccination, individual health translational medicine
How have humans altered the environment
- Moving into new environments
- Habitat destruction
- Pollution
- Farming
- Over population
- Waste
Emergence of new diseases in the era of environmental change
- Increase in new and reemerging diseases
- Increase in antibiotic drug resistance and rapid spread of pathogens
- Increased interaction with sylvatic animals
- Increased reliance on intensive animal farming
Why are new diseases emerging
- Increasing and aging population (more susceptible people)
- Intensive agriculture, increased land use, incursions into new environments
- Environmental damage, pollution, damage to health
- Increased use of antibiotics in farming
- Climate change (vector borne disease)
- Rapid global travel, trade and transport
How many new pathogens reported in last three decades and what % of which are zoonotic
More than 30, ~70% are zoonotic
Global hotspots for disease
Either:
- Interactions between human and wild life
- Regions of high population and transport
- Regions of war/natural disasters
- Regions of environmental damage
Animals and disease spread
- Pets
- In farming management
- Food
- In environment (sylvatic spread e.g. animal markets )
Stage 5 human exclusive agent
Only human transmission
Stage 4 long outbreak
Transmission from animals or (many cycles) humans
Stage 3 limited outbreak
Transmission from animals or (few cycles) humans
Stage 2 primary infection
Transmission only from animals
Stage 1 agent only in animals
No human transmission
Urban/epidemic cycle
Human <–> urban vectors or amplifying host
Enzootic/sylvatic cycle
- Reservoir host <–> primary vectors (enzootic vectors) –> dead end hosts
- Amplifies urban cycle
Epizootic/rural cycle
Amplifying host <–> primary or accessory vectors
what leads to re emergence of infectious disease
- Naive humans moving to area of high endemic transmission or bringing new diseases to naive populations
- Population growth
- Industrialisation
- Geopolitical
Impacts of human activity
- Travel
- Animal husbandry and agriculture
- Increasing population
- Environment interaction
- Climate change
Travel
- Human travel
- Infected food transported across the world every day (cannot keep up with disease
detection and surveillance) - Enhances spread of pathogens, infected people, vectors and infected reservoirs
Animal husbandry and Agriculture
- More intensive farming and destruction of habitat
- Reliance on mass production - Increasing use of chemicals, fertilisers and antibiotics
- Increasing food recycling poses danger to health
Increasing population
- Increased stress on the environment
- Increased interaction in new environments lead to increase risk of new disease emergence
- Increased geopolitical instability
- Ageing populations, increased susceptibility
Environment interaction
- Increasing usage of natural resources
-Increased generation of waste - Increasing pollution
- Food contamination, poor
environmental health –> poor human health
Climate change
- Co2 and pollution main drivers
- Earth is a finite environmental system
- Politically difficult to address
- Need a one health approach to sustain human life, animal diversity and environmental integrity
Microbial health
- Human health dependent on bodies microbial health (microbiome)
- Food and environment directly determines microbial makeup
- Microbial health determines both infectious and non transmissible disease
- Microbes important in animal health and environmental health
- Microbes as drivers and markers of health
