Climate Change Public Health ImpactsClimate Change Public Health Impacts

Helene G. Margolis, PhD

Environmental Health Investigations Branch Division of Environmental &Occupational Disease Control

Source: NASA

California Public Health Association – North

2008 Annual MeetingUC Davis, Davis, California

March 14, 2008

University of California, DavisDepartment of Internal Medicine

Overview

• Changing Planet: Net Results• Public Health Impacts: Opening Thoughts

– Comment on the current ‘big picture’ – Taking a broad perspective on “Vulnerability”

• Direct Effects• Effects Arising from Ecological Shifts &

Environmental Degradation• Public Health Impacts: Closing Thoughts

Our Changing Planet: Net Results Predicted Weather-related Consequences

“Virtually certain” Over most land areas • Warmer and fewer cold days and nights• Warmer and more frequent hot days and nights

“Very Likely” Over most areas

• Warm spells / heat waves. Frequency increases• Heavy precipitation events. Frequency (or proportion of total rainfall

from heavy falls) increases

→ increased risk of floods and/or damage to buildings hgm

“Likely”• Area affected by droughts increases• Intense tropical cyclone activity increases• Increased incidence of extreme high sea level (excludes tsunamis)

Source: IPCC Climate Change 2007: The Physical Science Basis: Summary for Policymakers

Public Health Impacts: Opening Thoughts Climate change will lead to amplification of: Most existent public health challenges....

Serious consequences in developed nations,catastrophic consequences in struggling nations.

Including health risks known to be associated with outdoor and indoor environments….

Currently no great surprises.

However, amplification will highlight and/or reveal weaknesses in public health and societal infrastructures.

Those weaknesses reflect vulnerabilities – at level of nations, regions, State, local (County, community, neighborhood), populations & individuals

Identification of those vulnerabilities in advance of crisis will serve us well in mitigation of climate change impacts.

Vulnerability: Conceptual Framework

As for most public health issues…

There are disparities in how climate change will impact different sub-populations, .e.g., lower socioeconomic groups, elderly, people of color.The relative impacts are a function of individual & population Vulnerability Vulnerability

In a lifetime everyone passes through stages of vulnerability.

Biological/Genetic Factors Physical Environmental Physical Environmental

FactorsFactorsSocial/Behavioral Social/Behavioral

FactorsFactors

’Individual’s Response

Exposure & Dose

Potential for Elevated Potential for Elevated Exposure & DoseExposure & DoseMost VulnerableMost VulnerableBiological Biological

SusceptibilitySusceptibility

The impact of environmental factors on populations… begins with impacts on individuals.

Environmental Impacts of Global Warming & SequelaeEnvironmental Impacts of Global Warming & Sequelae Greenhouse Gases =>Greenhouse Gases =>◊ ◊ Changing ClimateChanging Climate

↑ Long-term Ave. Temp. ↑ Freq. Hot Days/Nights

(& Heat Waves)↓ Freq. Cold Days/Nights↑ Heavy Rainfall Events

(without ↑ in total annual

precipitation)

↓ Snowfall & Snow pack↓ Mountain Glaciers↑ Drought (Areas, Freq. & Duration)↑ Tropical Cyclones &

Hurricanes (Freq. & Intensity)

↑ Extreme High Sea Level ◊ ◊ Plant Growth (COPlant Growth (CO22))◊ ◊ Ozone & photochemicalsOzone & photochemicals

““Exposures”Exposures”Extreme Weather Events

Heat WavesFloodsDroughts

WildfiresAir Pollution (O3, PM, GHG)Nuisance Plants

AllergensPesticides

Ecological Shifts =>Distribution & abundance of :

hosts, vectors, pathogens of Vector-Borne DiseasesWater-Borne Pathogens

Water-Food Supply & Quality

Malnutrition, diarrhea, harmful algal blooms

““Public Health Impacts”Public Health Impacts”Acute Morbidity/Mortality

InjuryHeat-related illnessChronic dz. acute eventsToxin-related illnesses

Chronic DiseaseRespiratory (Asthma, COPD, Allergy)

Cardiovascular (Atherosclerosis, ...

Communicable DiseaseV-B: West-Nile, malaria, dengue, encephalitis, hantavirus, Rift Valley feverW-B: Cholera, cryptosporidiosis, campylobacter, leptospirosis

Population DisplacementPsychosocial

Source: IPCC Climate Change 2007: The Physical Science Basis: Summary for Policymakers

• Extreme weather events (Heat waves, storms, floods, droughts, hurricanes, tornadoes)

– Short-time course events present immediate risk of • Death

• Injury & complications of injuries (e.g., wound infections)

• Infectious disease outbreaks

– Hurricane Katrina: ~1000 cases of diarrheal diseases (e.g., norovirus) among evacuees in Texas & Mississippi.

• Increased risk of exposures to toxic agents

• Psychosocial stress

• Disruption & Displacement

– Longer-time course events (e.g., droughts) • Greater adaptive capacity; Still pose risks to public health

Public Health Impacts: Direct Effects

• Temperature-related Illness and Mortality– Fewer cold- and heat-related deaths in past 30 yrs (US)

• Attributed to higher % of homes with central heat & AC

– Heat Wave: National Weather Service definition (e.g.)

≥ 3 consecutive days with temperatures ≥ 90°F (32.2°C)

Heat stress & exhaustionCrampingHeavy perspirationWeakness

Heat StrokeCore body temperature >104°FMulti-organ system dysfunctionOften fatal despite treatment

Public Health Impacts: Direct Effects

Risk Factors ExertionDehydrationChildren ≤ 5 years or Age >60 yearsLack of air conditioning Social isolationChronic diseases (CVD, COPD)Cognitive and mobility impairmentsLow socio-economic statusHousing characteristics

• Prevention requires knowledge not assumptions– Heat-related morbidity/mortality risk is greater in cooler

climates than in warmer climates• More northern latitudes and higher elevations• Attributed to less capacity to acclimatize through physiological,

behavioral, technological means.– Built environment

– Access/Use of AC

• Example: Weather-related influence on hospitalizations for cardiovascular diseases & stroke greater in San Francisco than in Los Angeles (Ebi KL et al. Int J Biometeorol 2004;49(1):48-58)

– Fans may contribute to heat stress & illness when high humidity (> ~33%) and high temperatures (≥ 90°F (32.2°C)) or temperatures ≥ 100°F (37.8°C).

Public Health Impacts: Direct Effects

Built Environment & Co-Exposures: Heat Islands, Topography & Ozone

El Dorado CountyBuilt-up rural area

Public Health Impacts: Simultaneous Risks

Heat-Related Deaths in Counties with ≥10 DeathsJuly 15 – August 1, 2006

Source: R. Trent, T. Kim. 2007. CDPH

99% of cases lived in zip codes where > 50% of residents live below Poverty Guide Line

Public Health Impacts: Direct Effects 2006 Heat Wave in California

• Economic impacts of heat wave on dairy industry ~ $1 Billion. 2006 California heat wave kills 16,500 dairy cows statewide.

(Other estimates – 25,000 in Central Valley or 1% of State’s Dairy Herd succumbedplus 70,000 poultry (Source:

http://news.bbc.co.uk/1/hi/world/americas/5223172.stm)

Central Valley saw disruption of animal breeding and>10% reduction in milk-production. Source: Fresno Bee: Mark Crosse

• Wide array of potential “downstream” public health risks e.g., water quality, communicable disease, psychosocial stress

Misters give cows some relief at Pacheco Dairy in Kerman, Fresno County.

Source: Modesto Bee/Marty BicekSource: Fresno Bee/Mark Crosse

Public Health Impacts: Indirect Impacts of Direct Effects

• Insect- & Animal-Borne DiseasesTemp, humidity, rainfall & sea level influence geographic distributions & population growth of infectious disease-causing pathogens (e.g., viruses, bacteria) & reservoir hosts (e.g., rodents, deer, birds) & vectors (e.g., mosquitoes, ticks, fleas)

which exist in complex ecologic relationships

Examples: 1992/1993 Hanta Virus outbreak (HV pulmonary syndrome) (New Mexico, Arizona, Colorado, Utah) drought followed by El-Nino

related heavy rainfall; ↑ mouse population & movement indoors 1999 West Nile Virus (WNV) – Arbovirus (mosquito-borne virus) associated with drought conditions First US cases in NY during hottest summer on record to that date CA -- by 2004 – 830 human cases across 58 counties

Public Health Impacts: Effects Arising from Ecological Shifts & Environmental Degradation

• Emergent & Re-emerging Infectious Diseases

– Potentially: • Malaria• Dengue• Viral encephalitides• Cholera• etc, etc., etc.

http://www3.niaid.nih.gov/research/topics/emerging/default.htm

Public Health Impacts: Effects Arising from Ecological Shifts & Environmental Degradation

• Water- & Food-Borne Diseases(Longer-term changes & extreme weather events)Naturally occurring toxins (e.g., phytoplankton – red tides)Infectious disease pathogens

• Relatively rare in U.S. Adequate food safety systems Good drinking water supply systems

• One failure can be costly1993 Cryptosporidiosis outbreak in Milwaukee

400,000 people infected$96 million ($32M direct medical; $65M lost

productivity) Attributed to drinking water contamination

Coincided with Mississippi River flooding• Reduced snow pack, altered rainfall….

↓ water supply (surface & groundwater)↓ water quality

Public Health Impacts: Effects Arising from Ecological Shifts & Environmental Degradation

• ↑ Temperature + ↑ UV radiation + primary emissions

= ↑ secondary air pollutants (ground-level ozone, particulates)• Predicted ↑ extreme heat episodes = ↑ electric power use

(= ↑ emissions & pollutant formation)

• Particulate Matter (PM) ≤ 10 (PM2.5, PM10-2.5) associated with

premature deaths Annual CA: 8800 (3000, 15,000 probable range)

hospitalizations Annual CA: 9500 (4600, 14,000 probable range)California Air Resources Board

• Ozone associated with 3-fold increased risk of new onset asthma among children who participate in ≥ 3 team sports

McConnell et al., Lancet 359: 386-391, 2002.

• Nitrogen dioxide & other combustion-related pollutants associated with permanent deficits in children’s lung function growth. Gauderman et al. New Engl. J. Med. 351(11):1057-67, 2004.

Public Health Impacts: Effects Arising from Ecological Shifts & Environmental Degradation

• Increases in Aeroallergens & Plant Biomass

• CO2 is essential to photosynthetic processes promotes plant growth

• ↑ CO2 = ↑ Invasive plant species

• ↑ Temperatures + ↑ CO2 = ↑ Ragweed in urban locations

(grew faster, flowered earlier, greater above-ground biomass & pollen)Ziska LH et al. J Allergy Clin Immunol 2003;111(2):290-5.

• ? Increase in asthma & allergy in urban communities?(↑ exposures to allergens or allergen+ diesel emissions)

Diaz-Sanchez, D. et al. Current Allergy and Asthma Reports 2003;3(2):146-52.

• ↑ Biomass + more arid conditions = ↑ risk of wildfires(↑ risk of injury & ↑ air pollution)

Public Health Impacts: Effects Arising from Ecological Shifts & Environmental Degradation

• Increased Risk of Exposure to Pesticides & Herbicides– Response to shifts in distributions of vector species,

agricultural pests and nuisance or invasive plants will likely lead to increased use of pesticides & herbicides

– ↑ Use in urban areas

(e.g., West Nile Virus eradication programs

short-term use may have + cost-benefits

long-term/frequent use cost-benefits unknown.)

– Residential developments near agricultural areas

Public Health Impacts: Effects Arising from Ecological Shifts & Environmental Degradation

To reduce vulnerability at individual, population or community levels:Promote good health (reduces risk, increases resilience)Ensure access to health care, medical managementImprove standard of care for all groups (Increase physician awareness)

Reduce potential exposure (individual, community)Prevention & ResponseEnsure response is adequate & does no harm(e.g., cooling centers & transportation; not fans)

In developing/applying solutions think about unintended consequencesunintended consequences. .

Investment of resources to mitigate climate-change health impacts can also contribute significantly to improvement of overall health of the public.

Public Health Impacts: Closing Thoughts Vulnerability, Disparities & Social Responsibility

Public Health Impacts: Closing Thoughts Actions

Public health networks– Develop a comprehensive and coordinated strategy to prevent or mitigate the hazards posed.– Strategies can capitalize on existing surveillance systems and databases to detect, track, evaluate, prepare for and respond to those hazards with optimum adaptive strategies. – Capitalize on existing public health, clinical and societal infrastructure to apply adaptive strategies.– Identify weaknesses in infrastructure/strategies & fix.

– Public health and environmental protection strategies need to be integrated, complementary...

• For example – Community actions to increase air conditioning in residences, need to be accompanied by actions that promote more green-energy production strategies.

– Public health and environmental protection strategies need to be Equitable.

– Public health community needs to be a partner in promotion of ‘climate change solutions.’

– Education & Outreach • Get the messages right & get them coordinated.

Public Health Impacts: Closing ThoughtsActions

Source: Patz, J. Nature: 438 (November 2005)

Public Health Impacts: Closing Thoughts Global Responsibility

“Climate Change Public Health Impacts Assessment and Response Work Group”

CDPH: EHIBCDPH: EHIBHelene Margolis, Ph.D., M.A.Paul English, Ph.D., M.P.H.Thomas Kim, M.D.Kathleen Fitzsimmons, M.P.H.

CDPH: EPICCDPH: EPICRoger Trent, Ph.D.

CDPH: DCDCCDPH: DCDCAnne Kjemtrup, D.V.M., Ph.D.Jonathan Kwan, Ph.D.

CDPH: EHLB – IAQSCDPH: EHLB – IAQSJed Waldman, Ph.D.

OEHHAOEHHABart Ostro, Ph.D.

Scripps Institution of Scripps Institution of OceanographyOceanography

Alexander Gershunov, Ph.D.

UC Berkeley/LBNLUC Berkeley/LBNLThomas McKone, Ph.D.Richard Jackson, M.D.

NRDCNRDC

Gina Solomon, M.D., M.P.H.

Miriam Rotkin-Ellman, Ph.D.

Zev Ross Spatial AnalysisZev Ross Spatial AnalysisIthaca, NY

Contact Information:

Helene G. Margolis, Ph.D., M.A. Helene G. Margolis, Ph.D., M.A.

hmargoli@cdph.ca.govhelene.margolis@ucdmc.ucdavis.edu 916-552-9837

Thank You!