Public Health Information Network (PHIN)

Series I

is for Epi

Epidemiology basics for non-epidemiologists

Series I Sessions

Title Date

“Epidemiology in the Context of Public Health”

January 12

“An Epidemiologist’s Tool Kit” February 3

“Descriptive and Analytic Epidemiology”

March 3

“Surveillance” April 7

“Epidemiology Specialties Applied” May 5

Session I – V Slides

VDH will post PHIN series slides on the following Web site:

http://www.vdh.virginia.gov/EPR/Training.asp

NCCPHP Training Web site:http://www.sph.unc.edu/nccphp/training

Site Sign-in Sheet

Please submit your site sign-in sheet andsession evaluation forms to:

Suzi SilversteinDirector, Education and Training

Emergency Preparedness & Response Programs

FAX: (804) 225 - 3888

Series ISession V

“Epidemiology Specialties Applied”

What to Expect. . .

TodayLearn about the application and practice of three Epidemiology specialties:

1. Disaster Epidemiology2. Environmental Epidemiology3. Forensic Epidemiology

Session Overview

• Disaster Epidemiology– North Carolina case study: Hurricanes– Impact of natural disasters– Rapid Needs Assessment methods and

technology

• Environmental Epidemiology– Virginia regulations– Environmental investigations

• Restaurant inspections

Session Overview (cont’d.)

• Forensic Epidemiology– Public Health Perspective– Law Enforcement Perspective– Joint Operations

Today’s 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

Today’s PresentersMark Smith, PhD, MS, MADirectorHealth Surveillance and Analysis UnitGuilford County Health Department, NC

Gary Hagy, MSEHDirectorDivision of Food and General Environmental ServicesVirginia Department of Health

Jennifer Horney, MPH, MAAssistant DirectorNC Center for Public Health Preparedness

Disaster Epidemiology

Mark Smith, PhD, MS, MADirector

Health Surveillance and Analysis UnitGuilford County Health Department

North Carolina

Public Health Grand Roundshttp://www.publichealthgrandrounds.unc.edu

• Click on “Archived Programs”• Broadcast title: “Disasters, People, and

Public Health: Are You Ready?”– September 1999, Hurricane Floyd – Immediate and long-term impact– Major components of a disaster response

plan– Mental health aspects for victims and

responders

North Carolina’s Evolving Public Health Response to

Natural Disasters

Rapid Needs Assessments after Hurricane Isabel and Charley

Overview

• NC’s Public Health Regional Surveillance Team (PHRST) Structure

• 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

NC Office of Public Health Preparedness and Response

Public Health Regional Surveillance Teams (PHRST)

Regional Team Members

• Physician-Epidemiologist• Nurse-Epidemiologist• Industrial Hygiene consultant• Administrative Assistant• Veterinarian liaison (NC Dept. Agriculture)• Three Pharmacist consultants shared

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.,

Ankara earthquake (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 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

Hurricane Isabel: September 18, 2003

Rapid Needs Assessment:Hurricane Isabel

• Thirty census clusters selected for a survey sample across 14 counties

• Ten assessment teams comprised of Public Health Regional Surveillance Team (PHRST) staff, UNC Chapel Hill School of Public Health students, and state agency volunteers deployed to “forward base” in Greenville

• 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

Interview ProcessOverview

• 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% flooded (95% CI 0.2 - 4.5)

• 32% damaged (95% CI 23 - 42)

• 65% no electricity

• 30% using a generator

Isabel RNA Results

• 43% bottled water supply

• 13% no access to 3-day food supply

• Household projections– 40,00 using bottled water– 12,000 no access to 3-day food supply

Lessons Learned

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 the computer, 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

                                                                                  

                     

                                                                                     

                                                           

GPS (Global Positioning System)

EPI InfoGIS

Field Team 1 Field Team 2 Field Team 3 Field Team 4 Field Team 5

Field data collection using IPAQ Pocket PCs equipped with GPS, GIS software and data collection forms.

Wireless: WIFI 802.11 or Bluetooth

Field Data Collection

Hurricane Charley: August 9-14, 2004

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

BKG_KEY Population Cumulative Random#371419803002 1281 1281371419803003 736 2017 1811371419803001 1397 3414371419802001 1725 5139 4569371419805001 1470 6609371419804004 1555 8164371419802002 1362 9526371419805002 1179 10705371419804001 714 11419371419804003 1182 12601371419804002 1081 13682 13067371419804005 1347 15029371419805004 1616 16645 15446371419806003 857 17502 17023371419805003 578 18080370479905002 1181 19261 19601371419806001 680 19941371419806002 2684 22625 21047371419802003 1329 23954370479905001 914 24868370479904001 1468 26336371419802004 1136 27472370479905003 532 28004371419802006 1497 29501370479908001 774 30275370479905004 1261 31536371419802005 2462 33998 32902370479903001 909 34907

Using Random Number Generator to Select 30 Geographic Clusters

1st Stage Randomization in Excel

Census Block Group Identifier

Census Block Group map layer has population data

In Excel, create cumulative population field to randomize “proportional to population”

Use random number generator in Excel to generate 30 numbers, select Census Block Groups

Identifying Individual Census Block Groups

Map made in Arcview 9.0

HP IPAQ Pocket PC running ArcPad GIS software

ArcPad Routing Function

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

EPI InfoGIS

Field Team 1 Field Team 2 Field Team 3 Field Team 4 Field Team 5

Field data collection using IPAQ Pocket PCs equipped with GPS, GIS software and data collection forms.

Wireless: WIFI 802.11 or Bluetooth

Field Data Collection

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 in. 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; i.e., tax parcels

Conclusions• RNA’s fulfill vital public health function

• Use of Incident Command System (ICS) 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

Question & Answer Opportunity

Mark Smithmsmith@co.guilford.nc.us

(336) 641 - 6844

Moderator Commentary

Disaster Epidemiology in The Context of The Series

5 minute break

Environmental Epidemiology

Gary Hagy, MSEH Director

Division of Food and General Environmental Services

Virginia Department of Health

Regulating Food Safetyin Virginia

VDH Office of Environmental Health Services

• Onsite Sewage and Water Services• Shellfish Sanitation• Wastewater Engineering

– Marina Program– Sludge

• Food and Environmental Services

• Any place where food is prepared for service…or any place where food is served

Restaurant - §35.1-1 Code of Virginia

Exemptions - §35.1-25• Churches, school,

fraternal organizations…

Administration

• State Board of Health

• State Health Commissioner

• District or Local Health Director

Three Primary Activities

Permitting

Inspecting

Enforcement

Permits

• Method of regulation operating through the “administrative lifting” of a legislative prohibition

• “Ministerial duty”

Denial of Permit

• Deny if not in compliance• Notify owner within 10 days• Reasons why• What needs to be done• 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

Lawful Inspections

• Access

• Recording observations

• Identifying corrective actions

Inspections versus Investigations

Inspections / Sampling• Restaurants• Milk

Investigations• Recalls• Outbreaks

Recording Observations

1. Cite section – 12 VAC 5-421-08202. Describe observation – paint a picture

– “Cooked chicken breast on steam line at 125ºF”

3. Describe corrective action– “Discard and ensure potentially hazardous

foods are hot held at 140ºF or above.” or– “Rapidly reheat the food to 165°F and

maintain at 140°F.”

Types of Violations

• Non-Critical

• Critical

• “Swing”

Enforcement

Types of Enforcement Action

• Permit suspension

• Permit revocation

• Impoundment

Permit Suspension(12 VAC 5-421-3770)

• Substantial or imminent threat• No hearing required• Written notice required• Opportunity for hearing• Owner may request hearing within 10

days• Hearing granted within three days• May end when reasons no longer exist

Substantial or Imminent 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 the Director

Permit Revocation(12 VAC 5-421-3780)

• Flagrant and continuing • 15-day notice • Opportunity for hearing

Impoundment(12 VAC 5-421-3960)

• Food believed to be in violation• Notice• ID• Service• Storage vs. destruction• Hearing

VENIS

VirginiaENvironmentalInformationSystem

Why Post Inspections?

• Public interest

Why Post Inspections?

• Public interest• Public documents

Why Post Inspections?

• Public interest• Public documents• Preempt legislation

Why Post Inspections?

• Public interest• Public documents• Preempt legislation• Enforcement

Scope of the Project

• 34 health districts in Virginia• 30 districts use BOH’s Food Regs• 4 districts use locally adopted codes• 35 different websites

What to Post?

• Grades?• Scores?• Summary?• Actual written report?

Actual Report

• Identifying information• Code citation• Observation and correction statements• Repeat violations identified• Critical violations identified• EHS comments

Public Response

Media Coverage

• Midday news• 6 o’clock news• 11 o’clock news

Day 1Good News

• The website was popular

Day 1Not so Good News

• The website was VERY popular!

May 1, 2003 Stats

• 841,672 hits• 25,627 visits• 557,723 page views• Peak Hour: 6:43 p.m. - 77,667 HPH• Peak Minute: 11:50 p.m. – 8,175 HPM

May 2003 Stats

• 8,496,272 Hits (274,073 HPD)• 446,432 Visits (14,401 VPD)• 5,541,435 Page Views (178,752 PPD)

Website Stats

• Launched May 1, 2003• >42.7 million hits (~60,000 per day)• >1.7 million visits (~2400 per day)• >9.4 million page views (>30,000 per day)• >189 GB of information transferred• Average visit about 11 minutes

Internet Posting of Inspections:Consumer Response

Dear Mr. Hagy,

Providing easy access to food safety inspections is a great service to the public.  I like being able to check out a restaurant's operational history before patronizing it.  In addition, I'm very impressed with and grateful for the thoroughness of the inspections that are conducted.  The potent combination of inspections and public scrutiny should make many foodservice establishments safer places to eat from now on.

Thanks!

G.Fredericksburg, Virginia

Hello – Just wanted to thank you for making this information available to the general public! My husband and I very appreciative of the efforts taken to put this information online. THANK YOU! THANK YOU! THANK YOU! M.M.Loudoun County

Question & AnswerOpportunity

Gary L. Hagygary.hagy@vdh.virginia.gov

(804) 864 - 7455

Moderator Commentary

Environmental Epidemiology in The Context of The Series

5 minute break

Forensic Epidemiology

Jennifer Horney, MPH, MAAssistant Director

NC Center for Public Health PreparednessUNC Chapel Hill

Learning Objectives

• Define Forensic Epidemiology; understand why discipline began, direction it is going, and challenges it faces

• Understand public health’s role in investigating natural outbreaks of disease and that certain unusual or unnatural findings in an investigation may suggest intentional criminal actions

• Understand the goals of public health and law enforcement officials and how these goals influence their investigations

• Understand differences between a law enforcement investigation and a public health investigation

Forensic Epidemiology

• Concept of merging public health methods in a setting of potential criminal investigation

Richard A. Goodman, CDC

What is Epidemiology?

• Study of distribution and determinants of health-related states or events in specified populations, and the application of this study to control of health problems*– Study risk associated with exposures– Identify and control epidemics– Monitor population rates of disease and

exposure

*Last JM, ed

A New Era in Public Health

• Investigation of health-related criminal cases

• Epidemiology can serve as a point of reference– Law, medicine, pharmacy, statistics, city

planning, emergency medical services

Forensic Epidemiology

• Past uses– Courtroom

• Current and future uses– Courtroom– Field-based investigations with law

enforcement

Epidemiology in the Courtroom

• Epidemiologists used to resolve disease-related litigation– Investigative experts– Consulting experts– Testimony experts

• Examples– Silicone breast implants, E. coli, tobacco use,

medical use of marijuana

Difficulties Using Epidemiology in the Courtroom

• Epidemiology studies disease in populations, not individuals

• Science is ever-changing

• Often difficult to prove exposure caused disease

Anthrax Investigations: 2001

• All isolates tested from 17 clinical specimens and 106 environmental samples in FL, D.C., NJ, NYC, and CT were indistinguishable

• Biological and physical evidence will be used to prosecute perpetrator(s)

Jernigan DB, 2002

Health-related Criminal Cases• Rabbit hemorrhagic disease virus; New Zealand,

1997

• Shigella; Dallas, TX, 1996

• Sarin; Japan 1990-95

• Anthrax– Failed release in Japan in early 1990s– Over 105 known hoaxes between 1998-2000

Field-based Forensic Epidemiology

Public HealthLaw

Enforcement

A Sample of Agencies Involved

• CDC• FBI• Local and state health

departments• Local, state, & federal

laboratories • State Highway Patrol • State Bureau of

Investigation• Hospitals and clinics

• Emergency Medical Services

• National Guard • Federal Emergency

Management Agency• United States

Department of Agriculture• Homeland Security• Attorney General’s office• Pharmacists• Media

Public Health and Law Enforcement Goals

Public Health• Make people safer

and healthier• Prevent disease

outbreaks• Conduct disease

surveillance and management

Law Enforcement• Protection of public• Prevention of criminal

acts• Identification,

apprehension, and prosecution of perpetrators

• Safeguarding all involved

Common Goals

• Protecting the public • Preventing or stopping the spread of

disease• Identifying those responsible for a threat or

attack• Protecting employees during response

and investigative phases

Martinez D, 2002, FBI

Mutual Benefits

• Law enforcement offers public health– Criminology expertise– Forensic laboratory collaboration– National and international law enforcement

connections

• Public health offers law enforcement– Medical and laboratory consultation– Collaboration with national and international public

health connectionsMartinez D, 2002, FBI

Differences in Public Health and Law Enforcement Investigations

• Criminal intent• Laws governing investigations• Sample/evidence collection• Confidentiality• Media interaction• Use of sensitive or secure information• Interviewing techniques

Criminal Intent

• Naturally occurring vs. criminally motivated event– Covert action– Overt action

Covert Attack

• Not initially recognized as an attack– Example: 1985 outbreak of gastroenteritis in

Oregon from salad bars initially thought to be from unintentional mishandling of food; found to be caused deliberately

• Public health officials usually recognize unusual signs, symptoms, or disease clusters through surveillance systems– First responders: emergency room, laboratory staff,

astute health care provider

Covert Response

Unusual Symptoms/Disease clusters

Notify state health department; conduct joint, preliminary epidemiologic investigation. If bioterrorist incident, notify FBI and CDC.

Adapted from Butler J, 2002

Preliminary public health

epidemiological, environmental investigation

Covert Attack: When to Notify FBI

• A case of smallpox or pulmonary anthrax• Uncommon agent or disease occurring in person

with no other explanation • Illness caused by a microorganism with

markedly atypical features • Illness due to food or water sabotage• One or more clusters of illnesses that remain

unexplained after a preliminary investigation• Deliberate chemical, industrial, radiation or

nuclear release

Overt Attack• Perpetrator announces responsibility for

something– 1995 sarin attack in Tokyo subway

• Law enforcement will usually detect event first– First responders: Emergency management

and law enforcement

• Often a hoax

Overt Response

Law enforcement identifies biological threat or potential biological materials.

FBI, Fire/Hazmat, local/state law enforcement notified.

Local or state public health notified. CDC notified.

Adapted from Butler J, 2002

Laws Governing an Investigation

• Public health officials have ability to– Examine medical records of person infected,

exposed, or suspected of being infected or exposed

– Implement control measures – Exercise quarantine and isolation authority – Enter premises where entry is necessary to

enforce public health laws• Law enforcement must obtain a search

warrant

Evidence• Law enforcement gathers evidence

• Public health gathers specimens

• Two criteria for specimens from public health investigations to be used in criminal investigations– Obtained as part of a legitimate public health

investigation– Collected and processed with a chain of custody

Legitimate Public Health Investigation

• Samples taken as part of a legitimate investigation of an outbreak or other public health situation may be used in a criminal investigation– Legitimate example: Collection of foods on a

salad bar due to a suspected outbreak– Incorrect example: Evidence found using

public health authority to inspect a hotel kitchen

Chain of Custody

• Required in law enforcement investigations

• Form providing– Name of person collecting evidence– Each person having custody of it– Date item collected or transferred– Agency and case numbers– Victim’s or suspect’s name – Brief description of item

Handling Credible Threat Evidence

• Handle as evidence and establish a chain of custody

• Process evidence through an approved Laboratory Response Network (LRN)

Public Health Laboratory

• Why is the Public Health Laboratory (PHL) Involved?– Mandate by Congress – Experience with biological agents of concern

and outbreak investigations– Link between local laboratory level, State,

CDC and other federal agencies

State Public Health Lab Role

• Disease identification and outbreak investigation• Reference services (additional, definitive testing

on isolates and specimens)• Specialized testing• Direct services• Environmental testing• Rapid testing• Applied research• Support of disease surveillance and

epidemiology investigations

Forensic Laboratory Role

• Conducts forensic examinations of evidence submitted by law enforcement agencies

• Firearms, Latent Evidence, Molecular Genetics, Documents, Drug Chemistry

• Works in partnership with the State Health Lab by educating LEO in proper protocols

• Forensic Lab does not conduct any biological hazard related testing but refers to State Health Laboratory / BSL III Labhttp://bmbl.od.nih.gov/sect3bsl2.htm

Forensic Laboratory Role

• Drug Chemistry and Toxicology• Latent Evidence Section• Trace Evidence Section• Molecular Genetics• Firearm and Toolmark• Documents and Digital Evidence

Working with the Media• Public health

– Open with media– Rely on media to get information to the public for

their protection

• Law enforcement– Not as open about ongoing investigations– Must preserve integrity of the case

• Joint Information Center (JIC)

Confidentiality

• Public health– Confidentiality of patient and medical records

• Law enforcement– Confidentiality of witness or informant

HIPAA

• Protected health information can be disclosed when:– Person exposed or at risk of contracting or

spreading a communicable disease created or caused by a terrorist act

– Weapons of Mass Destruction event causing public health issues

– Pursuant to court order, subpoena or administrative request from

– To identify or locate a suspect, fugitive or missing person

Classified / Sensitive Information

• Some public health officials should hold clearances to communicate with law enforcement when necessary

• Secure equipment should be available– Phone lines– Fax machines

Joint Interviewing

• Joint interviews with victims and witnesses

• Each discipline should be aware of the information counterparts seek– Law enforcement: personal, travel, incident,

safety, criminal investigation– Public health: personal, exposure, travel,

medical history

What’s So Different about Bioterrorism?

• High concentrations of agent dispersed• Large primary cohort exposed• Agent distributed in a well-traveled area• People present to different hospitals• May be second deliberate attack• Widespread panic• Hospitals may become flooded

Review• Forensic Epidemiology is the concept of joint public

health and law enforcement investigations in the setting of a potential criminal investigation

• Forensic Epidemiology was once primarily used in the courtroom, but is now increasingly used in the field to investigate health-related crimes, including bioterrorism

• While differences exist between public health and law enforcement investigations, by understanding the roles and responsibilities of each better, both can be more successful at protecting the public

Question & AnswerOpportunity

Moderator Commentary

Forensic Epidemiology in The Context of The Series

2005 Series II Preview!

“Outbreak Investigation Methods:From Mystery to Mastery”

“Outbreak Investigation Methods: From Mystery to Mastery”

Title Date“Recognizing an Outbreak” June 2

“Risk Communication” July 7

“Study Design” August 4

“Designing Questionnaires” September 1

“Interviewing Techniques” October 6

“Data Analysis” November 3

“Writing and Reviewing Epidemiological Literature”

December 1

Session V Slides

Following this program, please visit the Web site below to access and download a copy of today’s slides if you have not already done so:

http://www.vdh.virginia.gov/EPR/Training.asp

Don’t Forget!

Please submit your site sign-in sheet and session evaluation forms to:

Suzi SilversteinDirector, Education and Training

Emergency Preparedness & Response Programs

FAX: (804) 225 - 3888

References and Resources• Carus WS. Bioterrorism and biocrimes: The illicit use of

biological agents since 1900. Center for Counter proliferation Research, National Defense University, Washington, D.C.

• Centers for Disease Control and Prevention (CDC). http://www.phppo.cdc.gov/od/phlp/ForensicEpi/ForensicEpi.asp

• Jernigan DB, Raghunathan PL, Bell BP, Brechner R, et al. Investigation of bioterrorism-related Anthrax, United States, 2001: Epidemiologic findings. Emerging Infectious Diseases 2002;8:1019-28.

References and Resources• Last JM, ed. A Dictionary of Epidemiology, 3rd Ed,

New York, Oxford Univ Press, Inc., 1995.

• Law, D. (2005) Introduction to Geographic Information Systems. Methods in Field Epidemiology online course. UNC Chapel Hill School of Public Health.

• Martinez D. Presentation entitled Law Enforcement and Forensic Epidemiology at the Forensic Epidemiology Training Course. The Friday Center, Chapel Hill, North Carolina November 2-5, 2002.

References and Resources• Moore J. Responding to biological threats: The public

health system's communicable disease control authority. Health Law Bulletin 2001;78:1-10.

• National Institute of Justice. Accessed at http://www.ncjrs.org/txtfiles1/nij/178280.txt.

• NC Center for Public Health Preparedness (2004). Interviewing Techniques. Public Health Training and Information Network Broadcast.

• NC Center for Public Health Preparedness (2004). Designing Questionnaires. Public Health Training and Information Network Broadcast.

References and Resources• Inglesby, Thomas. Anthrax as a biological weapon.

JAMA 1999;281: 1735-1745.

• Torok, Thomas. A large community outbreak of Salmonellosis caused by intentional contamination of restaurant salad bars. JAMA 1997: 278: 389-395.

• Treadwell, Tracee. Epidemiologic clues to bioterrorism. Public Health Reports 2003; 118: 92-98.