Transcript Public Health Impacts: Direct Effects

Climate Change Public Health Impacts
Helene G. Margolis, PhD
Source: NASA
California Public Health Association – North
2008 Annual Meeting
UC Davis, Davis, California
March 14, 2008
Environmental Health Investigations Branch
Division of Environmental &
Occupational Disease Control
University of California, Davis
Department 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 subpopulations, .e.g., lower socioeconomic groups, elderly, people of color.
The relative impacts are a function of individual & population Vulnerability
The impact of environmental factors on populations… begins with impacts on individuals.
Biological
Susceptibility
Potential for Elevated
Most Vulnerable Exposure & Dose
’ Response
Individual’s
Exposure & Dose
Biological/Genetic
Factors
Physical Environmental
Factors
Social/Behavioral
Factors
In a lifetime everyone passes through stages of vulnerability.
Environmental Impacts of Global Warming & Sequelae
Greenhouse Gases =>
◊ Changing 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 (CO2)
◊ Ozone & photochemicals
“Exposures”
Extreme Weather Events
Heat Waves
Floods
Droughts
Wildfires
Air Pollution (O3, PM, GHG)
Nuisance Plants
Allergens
Pesticides
Ecological Shifts =>
Distribution & abundance of :
hosts, vectors, pathogens
of Vector-Borne Diseases
Water-Borne Pathogens
Water-Food Supply &
Quality
Malnutrition, diarrhea, harmful
algal blooms
“Public Health Impacts”
Acute Morbidity/Mortality
Injury
Heat-related illness
Chronic dz. acute events
Toxin-related illnesses
Chronic Disease
Respiratory
(Asthma, COPD, Allergy)
Cardiovascular
(Atherosclerosis, ...
Communicable Disease
V-B: West-Nile, malaria,
dengue, encephalitis,
hantavirus, Rift Valley fever
W-B: Cholera,
cryptosporidiosis,
campylobacter, leptospirosis
Population Displacement
Psychosocial
Source: IPCC Climate Change 2007: The Physical Science Basis: Summary for Policymakers
Public Health Impacts: Direct Effects
• 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 & exhaustion
Risk Factors
Cramping
Heavy perspiration
Weakness
Exertion
Dehydration
Children ≤ 5 years or Age >60 years
Lack of air conditioning
Social isolation
Chronic diseases (CVD, COPD)
Cognitive and mobility impairments
Low socio-economic status
Housing characteristics
Heat Stroke
Core body temperature >104°F
Multi-organ system dysfunction
Often fatal despite treatment
Public Health Impacts: Direct Effects
• 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: Simultaneous Risks
Built Environment & Co-Exposures: Heat Islands, Topography & Ozone
El Dorado County
Built-up rural area
Public Health Impacts: Direct Effects
2006 Heat Wave in California
Heat-Related Deaths in Counties with ≥10 Deaths
July 15 – August 1, 2006
99% of cases lived in zip codes where > 50%
of residents live below Poverty Guide Line
Source: R. Trent, T. Kim. 2007. CDPH
Public Health Impacts:
Indirect Impacts of Direct Effects
• 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 succumbed
plus 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: Fresno Bee/Mark Crosse
Source: Modesto Bee/Marty Bicek
Public Health Impacts: Effects Arising from
Ecological Shifts & Environmental Degradation
• Insect- & Animal-Borne Diseases
Temp, 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 costly
1993 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: Closing Thoughts
Vulnerability, Disparities & Social Responsibility
To reduce vulnerability at individual, population or community levels:
Promote good health (reduces risk, increases resilience)
Ensure access to health care, medical management
Improve standard of care for all groups (Increase physician awareness)
Reduce potential exposure (individual, community)
Prevention & Response
Ensure response is adequate & does no harm
(e.g., cooling centers & transportation; not fans)
In developing/applying solutions think about unintended 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
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 Impacts: Closing Thoughts
Actions
– 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 Thoughts
Global Responsibility
Source: Patz, J. Nature: 438 (November 2005)
“Climate Change Public Health Impacts Assessment
and Response Work Group”
CDPH: EHIB
Helene Margolis, Ph.D., M.A.
Paul English, Ph.D., M.P.H.
Thomas Kim, M.D.
Kathleen Fitzsimmons, M.P.H.
CDPH: EPIC
Roger Trent, Ph.D.
CDPH: DCDC
Anne Kjemtrup, D.V.M., Ph.D.
Jonathan Kwan, Ph.D.
CDPH: EHLB – IAQS
Jed Waldman, Ph.D.
OEHHA
Bart Ostro, Ph.D.
Scripps Institution of
Oceanography
Alexander Gershunov, Ph.D.
UC Berkeley/LBNL
Thomas McKone, Ph.D.
Richard Jackson, M.D.
NRDC
Gina Solomon, M.D., M.P.H.
Miriam Rotkin-Ellman, Ph.D.
Zev Ross Spatial Analysis
Ithaca, NY
Contact Information:
Helene G. Margolis, Ph.D., M.A.
[email protected]
[email protected]
916-552-9837
Thank
You!