Transcript CCHH - UCAR

Health Impacts of Climate
Variability and Change
Kristie L. Ebi, Ph.D., MPH
[email protected]
June 2006
Pathways for Weather to Affect
Health: Diarrheal Disease
Distal Causes
Proximal Causes
Temperature
Humidity
Precipitation
Survival/ replication Consumption of
of pathogens in the
contaminated water
environment
Living conditions
(water supply and
sanitation)
Food sources and
hygiene practices
Infection Hazards Health Outcome
Contamination of
water sources
Consumption of
contaminated food
Contamination of
food sources
Contact with
infected persons
Rate of person
to person contact
Incidence of
mortality and
morbidity
attributable
to diarrhea
Vulnerability
(e.g. age and
nutrition)
Potential Health Effects of Climate
Variability and Change
IPCC TAR–Potential Health
Impacts of Climate Change
• Increase in the geographic range of potential
transmission of malaria & other vector-borne
diseases
• Increase in heatwaves, often exacerbated by
increased humidity & urban air pollution
• Any increase in flooding could increase drowning,
diarrheal & respiratory diseases
• Increase in water- and food-borne diseases
The severity of impacts will depend on the capacity
to adapt & its effective deployment
Drivers of Health Issues
• Population growth
• Urbanization
• Public health funding
• Scientific developments
• Environmental conditions
• Populations at risk
–
–
–
–
Poor
Children
Increasing population of elderly residents
Immunocompromised
Estimating the Global Health
Impacts of Climate Change
Campbell-Lendrum et al. 2003
• 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)?
Comparative Risk Assessment
Greenhouse gas
emissions scenarios
Time
2020s
2050s
Global climate modelling:
2080s
Generates series of maps
of predicted future climate
Health impact model:
Estimates the change in relative
risk of specific diseases
2020s
Campbell-Lendrum et al. 2003
2050s
2080s
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)
Falciparum malaria (incidence)
Inland and coastal floods (mortality)
Heat and cold related CVD mortality
Campbell-Lendrum et al. 2003
Exposure: Alternative Future
Projections of GHG Emissions
• Unmitigated current GHG emissions trends
• Stabilization at 750 ppm CO2-equivalent
• Stabilization at 550 ppm CO2-equivalent
• 1961-1990 levels of GHGs with associated
climate
Source: UK Hadley Centre models
Campbell-Lendrum et al. 2003
Estimated Death and DALYs
Attributable to Climate Change
2000
Floods
2020
Malaria
Diarrhea
Malnutrition
120 100 80
60
40
20
Deaths (thousands)
Campbell-Lendrum et al. 2003
0
2
4
6
8
DALYs (millions)
10
Climate Change vs. Urban Air
Pollution
Millions of DALYs
Climate change
Urban Air Pollution
Africa Region
South-East Asia Region
Eastern Mediterranean Region
Latin America and Caribbean
Region
Western Pacific Region
Developed Countries
3000 2500 2000 1500 1000 500
0
500 1000 1500 2000 2500 3000
Burden of disease by region: Climate change and urban air pollution. Disability
Adjusted Life Year per million. World Health Report 2002.
Conclusions
• Climate change may already be causing a
significant burden in developing countries
• Unmitigated climate change is likely to
cause significant public health impacts out
to 2030
– Largest impacts from diarrhea,
malnutrition, and VBD
• Uncertainties include:
– Uncertainties in projections
– Effectiveness of interventions
– Changes in non-climatic factors
Campbell-Lendrum et al. 2003
Maximum Temperature
August 10, 2003
Chicago – Midway
(July Daily Maximum)
Now GFDL 2095
29.2° C 33.7° C
84.6° F 92.7° F
Standard deviation = 3.7° C
6.7° F
p = 36.3%
p = 5.7%
35.0° C
95.0° F
18.1° C 21.8° C
64.6° F 71.2° F
25.5° C 29.2° C 32.9° C 36.6° C 40.2° C 43.9° C 47.6° C
77.9° F 84.6° F 91.2° F 97.9° F 104.4° F 111.0° F 117.7° F
Emission Pathways, Climate Change,
and Impacts on California
Scenario
Heatwave days (Los
Angeles)
Length of heatwave
season
Heat-related
mortality (Los Angeles)
B1
A1fi
4X
6-8X
5-7
weeks
9-13
weeks
2-3X
5-7X
Hayhoe et al. 2004
Health Impacts of Floods
•Immediate deaths and
injuries
•Non specific increases
in mortality
•Infectious diseases –
leptospirosis, hepatitis,
diarrhoeal, respiratory,
& vector-borne diseases
•Exposure to toxic
substances
•Mental health effects
•Increased demands on
health systems
Philip Wijmans, LWF/ACT Mozambique, March 2000
Floods in Europe
1992: 1346 killed in Tajikistan
1993: 125 died in Yekaterinburg, Russia
1996: 86 died in the Biescas campsite, Spain
1998: 147 died in Sarno, Italy
2002: 120 died in Central Europe
Source: "EM-DAT: The OFDA/CRED International Disaster Database, www.em-dat.net - Université Catholique de
Louvain - Brussels - Belgium" Created on: May-23-2005. - Data version: v05.05
2000 Flood in Mozambique
• Heavy rains from Cyclones Connie and Eline in
February 2000 caused large scale flooding of the
Limpopo, Incomati, Save, and Umbeluzi rivers
– Environmental degradation and poor river system
management and protection contributed to the crisis
• 700 people died, 250,000 people were displaced
and 950,000 required humanitarian assistance (of
which 190,000 were children under the age of 5)
– 14,800 people were rescued by helicopter
Average Relative Change in Malaria
Incidence Before , During, and After El
Niño Events, Venezuela
Mean Change
2.0
Coast (1910-1935)
1.8
Whole country
Average of both
1.6
1.4
1.2
1.0
0.8
-2
-1
0 (Niño) +1
Time Lag (years)
+2
Bouma & Dye 1997
0°C average in Jan
“freeze line”
Malaria in Zimbabwe
Cases by Month
Source:
South African Malaria Research Programme
Ebi et al. Submitted
• Patterns of stable
transmission follow
pattern of
precipitation and
elevation (which in
turn influences
temperature)
• >9,500 deaths and
6.4 million cases
between 1989-1996
• Recent high-altitude
outbreaks
Climate and Stable Malaria
Transmission
• Climate suitability is a primary determinant
of whether the conditions in a particular
location are suitable for stable malaria
transmission
• A change in temperature may lengthen or
shorten the season in which mosquitoes or
parasites can survive
• Changes in precipitation or temperature may
result in conditions during the season of
transmission that are conducive to increased
or decreased parasite and vector populations
Ebi et al. 2005
Baseline
Ebi et al. 2005
2025
Ebi et al. 2005
2050
Ebi et al. 2005
2075
Ebi et al. 2005
2100
Ebi et al. 2005
Climate Change and Malaria Under
Different Scenarios (2080)
• Increase: East Africa, Central Asia, Russian Federation
• Decrease: Central America, Amazon
[within current vector limits]
Change of consecutive months
A1
> +2
+2
A2
-2
< -2
B1
B2
Van Lieshout et al. 2004
Effect of Temperature Variation on
Diarrheal Incidence in Lima, Peru
Daily
Diarrhea
Admissions
Daily
Temperature
Diarrhea increases by 8% for each 1 ºC increase
in temperature
Checkley et al. 2000
Temperature-Salmonella Models [fully adjusted]
lcl
ucl
rr
lcl
ucl
1500
rr
300
England & Wales
Switzerland
1000
200
500
100
0
0
0
5
10
Average 2 month temperature
lcl
ucl
15
20
0
rr
10
Average 2 month temperature
lcl
ucl
20
rr
80
150
Netherlands
Scotland
60
100
40
50
0
20
0
5
10
Average 2 month temperature
15
20
0
5
10
Average 2 month temperature
15
China Haze 10 January 2003
NASA
Air Pollution and Health
Number of days with surface ozone >180 µg/m3
1999
Summer 2003
EEA
Current and projected ranges of beech trees in the U.S.
Current
range
Current growth
GFDL — Geophysical Fluid Dynamics Laboratory
Source: U.S. Environmental Protection Agency, 1998.
GFDL
scenario
GISS
scenario
Projected new growth
GISS — Goddard Institute for Space Studies
Adaptation Needed Because:
• Climate change can not be totally avoided
• Climate change may be more rapid and more
pronounced than current estimates
• The severity of impacts will depend on the
capacity to adapt and its effective deployment
– Immediate benefits can be gained from better
adaptation to climate variability and extreme events
• Climate change brings opportunities as well as
threats
Thank you