Transcript Health impacts of climate change

The Effect of Climate on Infectious
Disease
• What changes will occur epidemiologically?
• How do we correlate changes in climate to
global changes in infectious disease?
• What technologies and tools are used to
analyze, predict, and monitor disease spread?
Robin Cochran-Dirksen
Kinds of health impacts resulting from
climate change:
• Direct- result from weather extremes.
• Consequences from ecological disruption.
• Consequences resulting from climate-induced
•
economic disruption, e.g. traumatic, infectious,
nutritional, psychological
Changes in human health as a result of climate
change will be indicated by alterations in geographic
range and seasonality of infectious diseases.
Robin Cochran-Dirksen
Robin Cochran-Dirksen
Challenges to connecting changes in
infectious disease to climate change.
•Climate influences are modulated by
interactions with other ecological processes,
social conditions, and adaptive policies.
•Climate change is just one environmental
change that simultaneously impact human
health.
Determinants of vectorborne diseases
• Vector survival and reproduction
• Biting rate
• Incubation rate
Robin Cochran-Dirksen
The tasks of the researchers
1. Establishing baseline relationships between
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weather and health.
Seeking evidence of early effects of climate
change.
Scenario-based predictive models
Evaluating adaptation options
Estimating the co-incidental benefits and
costs of mitigation and adaptation.
Robin Cochran-Dirksen
Environmental factors affecting
infectious disease
• Warmer temps enhance vector breeding and
reduce the pathogens maturation time within
the vector.
• Expanded pathogen/vector range introduces
the pathogen to populations with little
protective immunity.
Robin Cochran-Dirksen
Social factors affecting health
• Population density
• Level of economic development of the country
• Food availability
• Pre-existing health status
• Availability of health care
Robin Cochran-Dirksen
Historic evidence of the connection of
climate to infectious disease
• The link of climatic events has been studied
for a century in the Punjab.
Robin Cochran-Dirksen
Applying Technologies: Types of
Models
•Statistical
•Process Based
•Landscape-based Models
Robin Cochran-Dirksen
Statistical Models
• Work by deriving the relationship between
current geographic distribution and the
current location-specific climatic conditions
• These models have been applied to climate
impacts on malaria, dengue fever and in the
U.S., enchephalitis.
Robin Cochran-Dirksen
Process-based (mathematical) models
• Use equations that express the scientifically
documented relationship between climatic
variables and biological parameters- e.g.,
vector breeding, parasite incubation rate,
Robin Cochran-Dirksen
Landscape-based Modeling
• Combines the first two models with the use of
spatial analytical methods, to study the effects
of both climatic and other environmental
factors (e.g. different vegetation types- often
measured, in the model development stage by
ground-based or remote sensors).
Robin Cochran-Dirksen
Models allow them to create rubrics:
Robin Cochran-Dirksen
A Specific Example of Model
Application
• A study called Regional-scale climatevariability synchrony of cholera epidemics in
West Africa was published in 2007 in
Infectious Disease
• Methods: Wavelet and derived analyses of the
evolution of the periodic component over
time.
Robin Cochran-Dirksen
Wavelet analyses
Robin Cochran-Dirksen
Robin Cochran-Dirksen
Another example
• A monitoring program over several years in a
lake in Austria in order to identify the
preferred niche.
• Findings: they discovered a significant
correleation of the frequency of V. cholerae
with temperature, zooplankton biomass, and
conductivity.
Robin Cochran-Dirksen
Robin Cochran-Dirksen
The Future
Climate Change Global Risks, Challenges & Decisions
Conference
Held in Copenhagen 10-12 March, 2009 was attended
by more than 2,500 delegates from almost 80
countries.
The synthesis report will be published in June and
presented to all participants at the UN Climate
Change Conference to be held in December
Robin Cochran-Dirksen