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is for Epi. Epidemiology basics for non-epidemiologists. Session V Part I. Epidemiology Specialties Applied. What to Expect. . . . Learn about the application and practice of three epidemiology specialties: Disaster epidemiology Environmental epidemiology Forensic epidemiology.
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is for Epi Epidemiology basics for non-epidemiologists
Session VPart I Epidemiology Specialties Applied
What to Expect. . . Learn about the application and practice of three epidemiology specialties: • Disaster epidemiology • Environmental epidemiology • Forensic epidemiology
Learning Objectives • Be able to distinguish disaster, environmental, and forensic epidemiology specialties • Recognize the common epidemiological methods used among the three featured specialties • Recognize the special considerations or conditions faced by epidemiologists in each specialty • Appreciate how the context of law, media, business, and communities impacts epidemiology practice
Overview • Rapid Needs Assessments (RNAs) • GIS and GPS Technology • Hurricane Isabel: 2003 • RNA methods and lessons learned • Hurricane Charley: 2004 • Evolution of RNA methods and lessons learned
Rapid Needs Assessment After Natural Disasters • Identify need for food, water, power, shelter, access to medical care • Determine the magnitude of the need in order to plan and implement relief efforts. Purpose
Rapid Needs Assessment Background • RNA methodology developed by WHO and CDC • Used after hurricanes and other disasters, e.g., earthquake in Ankara, Turkey (1999), ice storm in Maine (1998), and hurricane in the Dominican Republic (1998) • Two-stage random sampling methodology allows generalization to sample area from only 210 completed surveys
Needs Assessment Sample 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
Rapid Needs Assessment:Hurricane Isabel • Thirty census clusters selected for a survey across 14 counties • Ten assessment teams comprised of • Public Health Regional Surveillance Teams (PHRSTs) • UNC School of Public Health students • State agency volunteers • Organized deployment using incident command system (ICS) structure
Rapid Needs Assessment Objective was to collect data about: • External or flood damage to homes • Access to household utilities • Incidence of hurricane-related illness and injury • Access to food and water • Access to medical care or medication • Immediate needs
Survey Instrument • One-page survey instrument • 24 questionnaire items • 33 data fields • Accompanied by a one-page “explanatory notes” form for interviewers
Interview Process • Assessment teams deployed in official vehicles to assigned census block area • From starting point, moved sequentially along roadways to collect data from seven households per cluster • Data collection was paper-based • Total of 210 interviews completed
Isabel RNA Results • 2% of households flooded • 32% of households damaged • 65% of households had no electricity • 30% of households using a generator
Isabel RNA Results • 43% of households used bottled water • That is 40,000 people • 13% of households no access to 3-day food supply • That is 12,000 people
Lessons Learned • Need for better randomization in second stage • Use of paper questionnaires required double data entry
Can new technologies address these issues? Options: • Perhaps geographic information systems (GIS) could be used in the 2nd stage randomization. • Skip the paper and enter the data directly into a handheld computer.
What is GIS? • Set of tools that collect, store, retrieve, transform, and display 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) – [Epi Map, ArcView] • Map layers share a common coordinate system (e.g., x - y)
GIS Mapping Example: John Snow’s Broad Street Pump Investigation
Field Data Collection EPI Info GIS Wireless: WIFI 802.11 or Bluetooth Field Team 4 Field Team 5 Field Team 1 Field Team 2 Field Team 3 Field data collection using IPAQ Pocket PCs equipped with GPS, GIS software and data collection forms.
Changes in RNA Methodology • Electronic field data collection • Use of GIS to randomly select households for interviews • Use of GIS and GPS to route interviewers to field data collection sites
Hurricane Charley RNA Assessment Area Map made in Arcview 9.0
Selection of Census Block Groups Map made in Arcview 9.0
HP IPAQ Pocket PC running ArcPad GIS software ArcPad Routing Function
ArcPad programmed to automatically insert cluster # in database for complex samples analysis ArcPad form programmed to automatically insert census block group population in survey Assigns a unique case ID or incident #
Field Data Collection EPI Info GIS Wireless: WIFI 802.11 or Bluetooth Field Team 4 Field Team 5 Field Team 1 Field Team 2 Field Team 3 Field data collection using IPAQ Pocket PCs equipped with GPS, GIS software and data collection forms.
Hurricane Charley RNA Results • 203 surveys completed • Training, data collection, analysis, report writing completed in 24 hours • Findings showed little impact from the hurricane • Estimated 1.4% of households without power • 6% of homes damaged but habitable • 2.5% of homes flooded with 1-12 inches water
Lessons Learned • Prepare data collection forms in advance, if possible • Provide mobile GIS training to potential field data collectors • Consider alternatives for second-stage randomization procedure; e.g., tax parcels
Conclusions • RNAs fulfill vital public health function • Use of incident command system (ICS) was vital to rapid deployment of resources • Handheld computers, GIS and GPS adds value to field data collection in RNA • Eliminates double data entry • Provides routing and direction-finding for field teams • Improved randomization through GIS • Ability to quickly analyze and map data
Environmental Health Services • Food Safety Services • Sewage and Water Services • Wastewater Engineering • Marina Program • Sludge • Shellfish Sanitation
Restaurant • Any place where food is prepared for service • Any place where food is served
Three Primary Activities Permitting Inspecting Enforcement
Permits • Method of regulation of operating through the “administrative lifting” of a legislative prohibition
Denial of Permit • Deny if not in compliance • Notify owner • Give reasons why denied • Assess what needs to be done • Owner has right to appeal
Inspections Staple of public health enforcement Similar to searches As often as necessary to ensure compliance Recorded on inspection form
Types of Inspections • Pre-opening • Routine • Critical Procedures • Follow-up • Training • Complaint
Inspections / Sampling Restaurants Milk Investigations Recalls Outbreaks Inspections versus Investigations
Types of Enforcement Action • Permit suspension • Permit revocation • Impoundment
Substantial Public Health Threats • Sewage back-up • Loss of water or contaminated supply • Loss of electrical power • Fire or flood • Communicable disease in foodservice worker • Loss of refrigeration • Other situation deemed by authorities