epidemiology applications: disaster and environmental epidemiology session 5, part 1
TRANSCRIPT
Epidemiology Applications: Disaster and Environmental Epidemiology
Session 5, Part 1
Learning ObjectivesSession 5, Part 1
• Identify epidemiology methods that can be used regardless of epidemiologic specialty
• Describe the Community Assessment for Public Health Emergency Response (CASPER) process
• List 4 functions of environmental epidemiology
OverviewSession 5, Part 1
• Framework for epidemiology specialties
• Disaster epidemiology methods
• Environmental epidemiology
Framework for Epidemiologic Applications
Reminder: What is Epidemiology?
• Study risk associated with exposures• Identify and control epidemics• Monitor population rates of disease and exposure
*Last JM, ed
“Study of the distribution and determinants of health-related states or events in specified populations, and the application of this study to the control of health problems.”
--From A Dictionary of Epidemiology, 3rd ed.
Goals of Epidemiology in a Health Department
• Collect and use high quality data
• Understand limitations of data
• Work to improve data collection and quality
• Use analytic results for planning and evaluation of disease and injury prevention programs
• Contribute new information for the understanding and prevention of disease and injury
Methods for Accomplishing Epidemiologic Goals
• Acute response
• Ongoing surveillance
• Epidemiologic analysis
• Dissemination of results
• Advocacy and enforcement
Disaster Epidemiology
Disaster Epidemiology-Defined
• CDC defines as: The use of epidemiology to assess the short- and long-term adverse health effects of disasters and to predict consequences of future disasters
• Unites various topic areas of
epidemiology, e.g. communicable disease, chronic disease, injury, mental health, etc.
Disaster Epidemiology Methodologies
• Rapid assessments using CASPER methods
• GIS and GPS Technology
• Examples of rapid needs assessment/ CASPER in disaster and non-disaster settings
– Example 1: PHRST 5 Tool
– Example 2: Hurricane Irene in NC, 2011
– Example 3: Community Health Assessments
– Example 4: KI distribution survey in NC, 2010
Definition of CASPER
• Format:– Face-to-face survey with
people living in affected area
• Target audience:– Decision-makers
• Benefits– Quick and low-cost– Accurate and useful
information
Hurricane Hugo, near Charleston, SC, September, 1989.Source: CDC Public Health Image Library
Purpose of a CASPER
Determine type and magnitude of needs to plan and implement relief efforts
What CASPERs are NOT
• Do not deliver food, medicine, medical services or other resources to the affected area
• Do not provide direct services to residents such as cleanup or home repair
CASPERSample Selection
• Select a sample area– Storm path, damage reports, service areas
• Randomly select 30 population weighted geographic clusters in sample area
• Randomly select 7 households within each geographic cluster
• 210 total surveys, 10 survey teams
GIS as a CASPER Tool
• Tools for storing, manipulating, analyzing and displaying spatial data
• Used to construct maps that communicate spatial data– Raster-based: Data and image stored in a
regularized grid made of pixels [Satellite]– Vector-based: Data and image stored separately in
map layers (points, lines, polygons) – [EpiInfo’s Epi Map, ArcMap]
• Map layers use x-y coordinate system based on latitude and longitude
GPS (Global Positioning System)
Field Team 1
Field Team 2
Field Team 3
Field Team 4
Field Team 5
Field data collection using handheld computers equipped with GPS, GIS software and data collection forms.
Field Data Collection
GIS Software
ArcPad Routing Function
ARCPad GIS Software on Handheld Computer
Assigns a unique case ID or incident #
ArcPad form programmed to automatically insert census block group population in survey
ArcPad programmed to automatically insert cluster # in database for complex samples analysis
Customized Form
Creating Forms in ArcPad Studio
Example 1: PHRST Tool for CASPER
PHRST Toolbar
created for ArcMap
Site selection toolkit freely available from UNC (cphp.sph.unc.edu/sharpgis/)
Stage 1
Stage 2
Example 2: Hurricane Irene, 2011
Hurricane IreneCASPER Results
• 205 interviews– 27.8% of respondents
evacuated– Only 35% of county
residents knew an evacuation order had been issued
– Evacuation rates highest among those living in 100 year flood plain
Example 3: Community Health Assessments
• Identify factors that affect the health of the population
• Determine the availability of resources to meet identified needs
• Collaborate with community leaders, public health, hospitals, private practitioners, academic partners
• CHA Report– Gives information about the
health of the community – Describes community
capacity to improve the lives of residents
• CASPER – Reduces the number of
surveys needed – Allows for efficient and
more accurate data collection
Community Health Assessments
• Very low household coverage rates (<5%)
• Knowledge of KI positively correlated with:– Age– Length of residence, – EPZ awareness and – White race
• Low levels of concern about nuclear accident
Example 4: KI Distribution Survey, 2010
Disaster Epidemiology Recap…
• CASPERs fulfill vital public health function
• Use of incident command system (ICS) is vital to rapid deployment of resources
• Handheld computers, GIS and GPS adds value to field data collection in rapid needs assessments– Eliminates double data entry– Provides routing and direction-finding for field teams– Improved randomization through GIS– Ability to quickly analyze and map data
Environmental Epidemiology
Mission of Environmental Epidemiology
• Reduce incidence and severity of disease and adverse health conditions due to environmental exposures
• Identify populations at risk of environmental exposures
• Understand and prevent disease and adverse health conditions
Environmental Epidemiology Programs
May exist alone or in combination with other epidemiologic disciplines:• Injury• Chronic• Occupational• Zoonotic• Toxicology
Core Functions of Environmental Epidemiology
• Conduct site-specific assessments
• Conduct health, environmental, and biological surveillance
• Respond to community concerns
• Conduct health professional and community education
Technical Assistance and Partner Relationships
• Cooperation and coordination with EPA and local health departments
• State departments of Environment / Environmental Management / Natural Resources– Chemical release– Planning and public communications– Human-environment interaction
• State-based hazard and pollution programs
Preparedness
• Technical support for response planning and implementation
• Education and outreach– High-risk populations– First responders
• Identify vulnerable populations• Chemical terrorism fact sheets
Other Programs in Environmental Epidemiology
• Toxins, occupational exposures– Blood lead– Asbestosis– Silicosis
• Pesticides• Air pollution• Hazardous waste• Special studies
Summary
• Epidemiology methods can have many applications
• Disaster epidemiology to assess disaster impacts, guide response and prepare for future disasters
• Environmental epidemiology monitors populations for health repercussions of environmental contamination
References• Last JM. A Dictionary of Epidemiology. 3rd ed. New York, NY: Oxford
University Press; 1995.• Law D. Introduction to Geographic Information Systems. Methods in Field
Epidemiology Lecture Series. Department of Epidemiology, University of North Carolina at Chapel Hill School of Public Health; 2005.
• Malilay J, Flanders WD, Brogan D. A modified cluster-sampling method for post-disaster rapid assessment of needs. Bull World Health Organ. 1996;74(4):399-405.
• MacDonald PDM. Methods in Field Epidemiology. Burlington, Mass: Jones & Bartlett Learning; 2012.
• Beitsch LM, Brooks RG, Grigg M, Menachemi N. Structure and Functions of State Public Health Agencies. Am J Public Health. 2006;96(1):167-172. Available at: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1470433/. Accessed December 29, 2011.
• Health Studies Branch - Preparedness and Response for Public Health Disasters. [Web page.] National Center for Environmental Health, Centers for Disease Control and Prevention. Available at: http://www.cdc.gov/nceh/hsb/disaster/. Accessed March 1, 2012.