Planetary Health Notes

Planetary health focuses on safeguarding the health and well-being of current and future generations through good stewardship of Earth's natural systems.
It involves rethinking how we feed, move, house, power, and care for the world.

Boyden's Biosensitivity Triangle:
- Highlights the interconnectedness of human activities, human health, and planetary health.
Cultural Transformation:
- Emphasizes the need to manage ourselves to leave no one behind.
- Considers our culture, mindset, values, education, regulations, rules, laws, and economic systems.
Five Pathways for Rethinking and Transition:
- Feeding the World: Transitioning to more sustainable agri-food systems.
- Moving the World: Re-evaluating and transforming transport systems.
- Housing the World: Rethinking housing for people, animals, workplaces, and industries.
- Powering the World: Urgent transition to renewable energy.
- Caring for the World: Reducing the environmental footprint of the healthcare system and caring for nature.
Bottom Line: Our future depends on the health of the natural world.

Eco-Social Approach:
- Understanding health problems and challenges by recognizing ecological, economic, and social determinants of health.
- Complementing biomedical approaches with this integrated perspective.
Systems Thinking:
- Acknowledging the interdependence of all species on Earth, including microorganisms.
- Balancing focus on pathogens with recognition of beneficial microorganisms (e.g., trillions on our mucosa).
Intergenerational Health Equity:
- Considering the legacy and implications for future generations.
- Looking beyond current populations to the impact on generations ahead.
Indigenous and Local Knowledge:
- Valuing Indigenous and local knowledge through a transdisciplinary approach.
Planetary Consciousness:
- Bringing awareness of planetary implications to health research, education, policy, and practice.
- Considering the impact of choices and behaviors on our health and the health of natural systems.

Human ecology is a way of understanding patterns of human health, alongside epidemiology as a core method in health research, education, policy, and practice.
Stephen Boyden's work emphasizes that all human activities have potential positive or negative impacts on our health and the health of the planet.
Acknowledges the ecological determinants of health alongside social determinants.
Reinforces the importance of systems thinking and understanding unintended consequences.
Highlights need to consider feedbacks when making changes in one part of the system.

MJA Lancet Countdown on Health and Climate Change:
- An annual report tracking trend lines for indicators such as:
  - Number of people displaced by weather-related disasters (2008-2020).
  - Annual person days exposed to landscape fire in Australia.
  - Average annual number of days exceeding heat stress risk thresholds in Australian cities.
Carbon Footprint of Healthcare:
- Assessment of the carbon footprint of Australian healthcare: Approximately 7% of Australia's emissions are attributable to the healthcare system.
- Global assessment of the environmental footprint of healthcare, considering emissions and waste.
Climate Change in Australia’s Healthcare Systems Report:
- Systematic review of how health systems worldwide are responding to climate change.
- Policy and institutional analysis of climate and health policy-making.
- Case studies from various geographic regions in Australia.
- Economic analysis using the health burden from bushfires as an example.

Planetary Health: The health of human civilisation and the state of the natural systems on which it depends.

Escalating Human Pressures:
- Pressures on the global environment.
Environmental Changes and Ecosystem Impairments:
- Climate change, ozone depletion, deforestation, land degradation, wetland loss, biodiversity loss, freshwater depletion, urbanization, and damage to coral reefs.
Health Effects:
- Direct Health Effects: Floods, heat waves, bushfires, water shortages, landslides, and pollution.
- Ecosystem Mediated Health Effects: Alterations to infectious disease risk, reduced food yields, depletion of natural medicines, and mental health consequences.
- Indirect, Deferred, and Displaced Health Effects: Loss of livelihoods, displacement, slum dwelling, conflict, and inappropriate adaptation and mitigation.

Climate change (temperature extremes, $CO_2$ fertilization, impact on pests, mould, and fungi).
Land degradation and soil erosion.
Water scarcity.
Loss of pollinators.
Overfishing and ocean acidification.

More than 3 million deaths annually from ambient particulate pollution.
More than 4 million deaths from household-level pollution from burning solid fuels.
Totaling over 7 million air pollution-related deaths worldwide.

Emergence of new infections (H5N1, SARS, Ebola, Zika, SARS-CoV-2) due to environmental and social changes.
Climate change, urbanization, and forest clearance leading to spillover of pathogens from wild to domestic animals to humans.
Accelerated rates of emergence of new pathogens.

Global average life expectancy increased from the low 50s to the high 60s between 1960 and 2010, and is now in the low 70s.
Disparities in life expectancy remain, with lower expectancy in Africa, South Central, and West Asian regions.

Health improvements have come at the cost of unprecedented exploitation of the planet.
Escalating carbon dioxide emissions, ocean acidification, energy use, global deforestation, water use, and fertilizer use.