Training for health professionals

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Overview

• Direct and indirect impacts

• Projected health impacts

• Global health impacts

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Direct / indirect impacts

• Climate change can impact directly on health – e.g. through UV radiation, heat stress, accidents caused by storms.

• It can also impact indirectly – e.g. by altering conditions for disease vectors, reducing agricultural productivity, and triggering conflict over scarce resources.

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Direct / indirect impacts

"The intimate connection between food security, water security, energy security and climate change - to deal with one in

isolation is to present enormous problems”

Professor John Beddington, Chief Scientific Advisor to the Government, speaking at The Climate Connection national

launch, 2nd December 2008

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Climate Change is Happening Now

Source: IPCC 2007 (4th Assessment)

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IPCC 2007: Human Impact is Evident

Source: IPCC 2007 (4th Assessment)

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1°C 2°C 5°C4°C3°C

Sea level rise threatens major cities

Falling crop yields in many areas, particularly developing regions

FoodFood

WaterWater

EcosystemsEcosystems

Risk of Abrupt and Risk of Abrupt and Major Irreversible Major Irreversible ChangesChanges

0°C

Falling yields in many developed regions

Rising number of species face extinction

Increasing risk of dangerous feedbacks and abrupt, large-scale shifts in the climate system

Significant decreases in water availability in many areas, including Mediterranean and Southern Africa

Small mountain glaciers disappear – water supplies threatened in several areas

Extensive Damage to Coral Reefs

Extreme Extreme Weather Weather EventsEvents

Rising intensity of storms, forest fires, droughts, flooding and heat waves

Possible rising yields in some high latitude regions450 ppm CO2 eq

650 ppm CO2 eq

Projected Impacts of GlobalTemperature Change

Source: L. Rudolph, 2008

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Climate Change’s Impacts on Health

Source: Haines, et al, JAMA 2004

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Extreme Weather Events & Disease Clusters

Source: Epstein, Harvard Center for Health & Global Environment

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Human Changes to Global Activated Nitrogen Cycle, 1900-2050

• Human health risks include:– Decreased crop

yields– Nitrogen oxides

(air pollution)

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National Carbon Dioxide Emissions

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Total CO2 Emissions

UNEP 2009

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Health Burden of Climate Change Impacts

Deaths from malaria and dengue fever, diarrhoea, malnutrition, flooding, and (in OECD countries) heatwaves

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Painful spots

• Core knowledge: the effects of climate change on current responsibilities of Environmental Health– air, water, food, pest control, home health

• Areas for development: Environmental Health Practitioners as agents for carbon reduction and adaptation.– air, carbon, water, food, housing

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• Air quality

• Water safety

• Food safety

• Pest control

• Housing

Climate change affects the current responsibilities of Environmental Health

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Air qualityClimate change impacts

• Increasing temperatures combine with air pollution to increase ground level ozone, causing morbidity from respiratory disease.

• Tighter controls on pollution to air may be needed just to maintain current air quality.

• Surveillance and early warning systems for vulnerable groups.

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China Haze 10 January 2003

NASA

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Health impacts of climate change

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Projected impacts

• Heatwave-related health problems

• Cold-related illness & deaths

• Air pollution

• Flooding

• Infectious diseases - food borne, waterborne and vector-borne diseases

• Exposure to UV radiation

• Extreme weather-related events

• New threats appropriate responses

• Possible supplementary health benefits

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Pathways for Weather to Affect Health: Example = Diarrheal Disease

TemperatureHumidityPrecipitation

Distal Causes Proximal Causes Infection Hazards Health Outcome

Living conditions(water supply andsanitation)

Food sources andhygiene practices

Survival/ replicationof pathogens in theenvironment

Contamination ofwater sources

Rate of personto person contact

Consumption ofcontaminated water

Consumption ofcontaminated food

Contact withinfected persons

Incidence of mortality andmorbidityattributableto diarrhea

Vulnerability(e.g. age andnutrition)

Contamination of food sources

WHO

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Daily Temperature

Daily Diarrhea Admissions

Diarrhea increases by 8% for each 1ºC increase in temperature

Effect of Temperature Variation on Diarrheal Incidence in Lima, Peru

Checkley et al., 2000

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Corvalan et al., 2003

Pathways from Driving Forces to Potential Health Impacts

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Climate Change may entail changes in variance, as well as changes in mean

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Methods for:

• Estimating the current distribution and burden of climate-sensitive diseases

• Estimating future health impacts attributable to climate change

• Identifying current and future adaptation options to reduce the burden of disease

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Estimate Potential Future Health Impacts

• Requires using climate scenarios• Can use top-down or bottom-up

approaches– Models can be complex spatial models or be

based on a simple exposure-response relationship

• Should include projections of how other relevant factors may change

• Uncertainty must be addressed explicitly

After Kovats et al., 2003

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Sources of Uncertainty

• Data– Missing data or errors in data

• Models– Uncertainty regarding predictability of the system– Uncertainty introduced by simplifying relationships

• Other– Inappropriate spatial or temporal data– Inappropriate assumptions– Uncertainty about predictive ability of scenarios

Kovats et al., 2003

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Estimating the Global Health Impacts of Climate Change

• What will be the total potential health impact caused by climate change (2000 to 2030)?

• How much of this could be avoided by reducing the risk factor (i.e. stabilizing greenhouse gas (GHG) emissions)?

Campbell-Lendrum et al., 2003

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Comparative Risk Assessment

2020s

2050s

2080s

Greenhouse gas emissions scenarios

Global climate modelling:

Generates series of maps of predicted future climate

Health impact model: Estimates the change in relative risk of specific diseases

Campbell-Lendrum et al., 2003

Time

2080s2050s2020s

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Criteria for Selection of Health Outcomes

• Sensitive to climate variation• Important global health burden• Quantitative model available at the global scale

– Malnutrition (prevalence)– Diarrhoeal disease (incidence)– Vector-borne diseases – dengue and falciparum

malaria – Inland and coastal floods (mortality)– Heat and cold related CVD mortality

Campbell-Lendrum et al., 2003

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Due to both direct & indirect effects:

• Increased physical activity due to extended warm weather. But, outcomes could be worse due to extreme heat

• Reduced obesity and road traffic injuries through active transport

• Possibly healthy eating through adoption of sustainable farming & food policy and diets containing less animal products

• Reduced respiratory illness by improvements in air quality

• Increased home energy efficiency reducing temperature-related illness

Potential health benefits

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Global health impacts of climate change

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Climate change affects the most fundamental determinants of health: air, food, water, shelter, freedom from disease.

The impacts on human health are not evenly distributed. Developing country populations, particularly in small island states, arid and high mountain zones, and in densely populated coastal areas, are first and hardest hit.

Global health impacts

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WHO: five major health impacts of climate change

1. Malnutrition

2. Deaths and injuries caused by storms and floods. (Flooding can also be followed by outbreaks of diseases, such as cholera)

3. Water scarcity / contamination (droughts and sudden floods) – increased burden of diarrhoeal disease.

4. Heatwaves – direct increases in morbidity and mortality; indirect effects via increases in ground-level ozone, contributing to asthma attacks.

5. Vector-borne disease – malaria and dengue.

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Major global killers are affected by climate

Each year:• Weather– related disasters kill over 60,000• Undernutrition kills 3.5 million • Diarrhoea kills 2.2 million• Malaria kills 900,000

(WHO, 2003, 2008)

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• Can take the long view• Understands the science• Other health initiatives will be overtaken by the

effects of climate change• Action on climate change has health effects

itself– Positive (“health co-benefits”)– Negative

Why the health sector?

Climate Negotiations

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1) Raising awareness: of the health implications of climate change

2) Strengthening partnerships: to place health at the centre of climate change policy

3) Generating evidence: on the health effects of adaptation and mitigation policies

4) Strengthening public health systems to cope with additional threats posed by climate change

Main objectives for international public health

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With impoverished populations in the developing world the first and hardest hit, climate change is very likely to increase the number of preventable deaths. The gaps in health outcomes we are trying so hard to address

right now may grow even greater.This is unacceptable.

Climate change and health: preparing for unprecedented challenges.WHO Director General Margaret Chan.

December, 2007

1. Raising awareness

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Why health should be central:

• Main reasons for concern (e.g. disasters, food shortage, displacement, disease) are health and wellbeing issues

• Most energy and environment decisions (e.g. choice, use of fuel sources) have major direct health implications

2. Partnerships to raise the profile of health in climate change policy

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3. Providing Evidence - Health Adaptation

• Describing risks from national to global level

• Measuring the effectiveness of interventions

• Evaluating health effects from decisions in other sectors

• Improving decision-support tools

• Assessing the financial costs

Protection of handwashing against diarrhoea, highlighting studies in water-stressed situations.

Adapted from Curtis V, Cairncross S. 2003; Lancet Inf Dis 3:275-281

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"Health benefits from reduced air pollution as a result of actions to reduce greenhouse gas emissions… may offset a substantial fraction of mitigation costs" – IPCC, 2007

We have an opportunity to reduce:

- The 800,000 annual deaths from urban air pollution, and the 1.6 million from indoor air pollution

- The loss of 1.9 million lives, and 19 million years of healthy life, from physical inactivity

- The 1.2 million deaths and over 50 million injuries from road traffic accidents

3. Providing Evidence: Improving health while reducing greenhouse gas emissions

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4. Strengthening public health systems

Strengthened action on diseases of poverty: Including wider coverage with vector control and vaccination programmes.

Much of "adaptation" is basic, preventive public health:Improved surveillance and response: E.g. heatwave warnings, compliance with International Health Regulations to prevent international spread of disease.Better management of environmental health determinants: Provision of safe water and sanitation, control of air pollution

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DISCLAIMERThe views expressed in this presentation are those of the authors within the Climate TRAP project and do not necessarily reflect the views or policies of any participating organisation.