Module 2:
O tb k Determination
Outbreak
D t
i ti
and Investigation
g
Epidemiology Division
Surveillance Branch
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
Module Learning Objectives
„
„
„
„
List steps needed to prepare for an
investigation
Define foodborne outbreak (FBO)
Gather information to determine the
source
Identify means for searching for
additional
ddi i
l cases
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
2
M d l LLearning
Module
i g Objectives
Obj ti
((cont.)
t)
„
„
„
„
„
List three phases of interviewing
Describe methods to ensure
consistency of interview data
List steps for obtaining a case
history
Describe methods for overcoming
b i
barriers
to iinterviewing
i i
Perform group exercise
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
3
Outbreak Determination
Flow Diagram
Generate
termination
report
Collect Food
Samples
Environmental Health
Prepare
Investigation
Take steps to
verify
diagnosis
Get Case
History
Surveillance Staff
NO
Develop initial
case definition
Make
epidemiologic
(time, place,
person)
associations
Obtain Clinical
Specimens
Surveillance & Med Providers
Determine
if an outbreak
occurred
YES
Outbreak
Investigation
Remember the Three-Legged Stool: Epidemiology, Environmental Health, & Laboratory
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
4
Steps to Prepare for Investigation
„
„
„
Follow Foodborne Outbreak (FBO)
Protocol (see Intro Module)
Complete Preliminary Outbreak
Investigation Report
Notify DETECT Team
„
Minimally Field Surveillance Staff (FSS)
and 2 Environmentalists (Env)
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
5
Additional Investigation Preparation
„
Grab your DETECT Kits
„
„
Human & environmental sample
collection kit
Plan and Train:
„
„
„
Team members understand their role
according to protocol
Cannot address every situation
Reduces confusion during the crisis
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
6
Is
I it a ffoodborne
db
outbreak?
tb k?
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
7
Foodborne Illness
Outbreak Definition
CDC and IAFP Definition
persons have the
An outbreak is an incident in which two or more p
same disease, have similar clinical features, or have the same
pathogen – thus meeting the case definition - and there is a time,
place or person association among these persons.
persons
A foodborne outbreak is one that is traceable to ingestion of a
contaminated food.
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
8
Foodborne Illness
Outbreak Definition (cont.)
CDC and IAFP Definition
A single
g case of suspected
p
botulism,, mushroom ppoisoning,
g,
ciguatera or paralytic shellfish poisoning or other rare
disease, or a case of a disease that can be definitely related
to ingestion of a food,
food can be considered an incident of
foodborne illness and warrants further investigation.
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
9
Foodborne Outbreak Definition
Alabama Definition
An incident in which two or more persons from
different households experience a similar illness
resulting from the ingestion of a common food.
Exceptions:
E
ti
botulism
b t li andd chemical
h i l poisoning
i i
(1 case = outbreak).
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
10
Next Steps
„
„
„
Gather
G
th iinformation
f
ti tto d
determine
t
i
source
Search for additional cases
Begin
g Interviews
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
11
Information to
Determine Source
„
„
„
„
„
Preliminary Outbreak Investigation
Report
O tb k
Outbreak-specific
ifi Q
Questionnaires
ti
i
Environmental Inspection Report
Clinical and food specimen test
results
Healthcare provider medical records
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
12
S
Search
h for
f Additi
Additionall Cases
C
„
C
Communicate
i t with
ith C
Community
it
„
„
„
„
Health Care Facilities
Schools
Private Providers
Exposure Location
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
13
Interviewing Objectives
„
To determine source of illness and
means of transmission
„
Minimize repeat interviews
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
14
B gi IInterviews
Begin
t i
„
Central Office Epi Provides
„
„
„
„
„
„
Outbreak-specific Questionnaire
Case Definition
Who to Interview
Outbreak Name
Type of Specimen
Additi
Additional
lC
Consultation
lt ti
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
15
T Ways
Two
W
tto Obt
Obtain
i IInformation
f
ti
„
I t i
Interviewer
Led
L d
„
„
„
In-person
Telephone
Self Administered
„
„
Web-based
Forms distributed
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
16
Self--Administered Questionnaires
Self
„
„
Alternative to in-person or telephone
interviews
Limitations
„
„
„
Poor response rates
Respondent
p
can misinterpret
p or fail to
understand questions
Advantage
„
Reduce resources devoted to gathering
information, esp. with large outbreaks
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
17
Three
Th
Ph
Phases off IInterviewing
t i i g
1. Before
2. During
3. After
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
18
Before
B f
IInterviewing
t i i g
„
„
„
„
Review working case definition
Obtain outbreak-specific
questionnaire
ti
i ffrom Epi
E i
Assess workload
Id tif and
Identify
d train
t i interviewers
i t i
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
19
Develop the Working
Case Definition
Person, Place and Time
„ Laboratory Data
„ Environmental Data
„
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
20
Outbreak Questionnaire Format
„
Demographic information
„
„
Exposure history
„
„
Age, gender, address, other
identifying data
F d consumption
Food
ti
Disease information
„
Symptoms/signs
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
21
O
OpenOpen
-Ended
E d d Questions
Q
ti
„
„
„
„
„
Rarely used
Data gathering
Hypothesis generating
Drawback - difficult to analyze
statistically
Time consuming
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
22
C t i dF
Customized
Forms
Gather
G
th specific
ifi info
i f after
ft
have basic initial information
„ Read all questions in the
order as theyy appear
pp
on
questionnaire
„
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
23
ClosedCl
Closed
d-Ended
E d d Questions
Q
ti
„
„
„
„
Preferred
P
f
d
Gather specific information
Can be restrictive and leading
Can target specific topics
Yes
Yes______
No
No_______
Unknown
Unknown______
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
24
B f
Before
IInterviewing…Remember
t i i g R
b
„
B consistent
Be
i t t in
i interviews
i t i
„
Become familiar
B
f ili with
ith questionnaire
ti
i
before conducting interviews
„
Practice with someone on team
before interviews begin
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
25
A Good
G d IInterview
t i iis a Must
M t
„
Accurate and complete data required
„
Obtain answers for all questions, even
if “unknown”
unknown
„
Interview 3 “not ill” for every 1 “ill”
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
26
Assessing
A
i gW
Workload
kl d
„
Identify and prepare interviewers
„
„
„
Assign interviewers; training for all
Arrange work schedules (24/7 work)
Assess workload
„
„
Number of interviews needed
Types of individuals to interview
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
27
Outbreak Investigation
Interviewing Skills
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
28
Three
Th
Ph
Phases off IInterviewing
t i i g
1. Before
2. During
3. After
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
29
During Interviews
„
„
„
Establish rapport
Identif self and organi
Identify
organization
ation
Reason for investigation
„
„
„
„
Need to indentify source and prevent others
from getting sick
Express empathy
May be contacted multiple times
Start with easy questions
„
“Your name/ address/ occupation?”
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
30
A
Assess
Communication
C
i ti St
Styles
l
„
Identify communication style of
interviewee and adjust your style to
match
„
„
„
„
Action - bottom line / “Just the facts”
Feeling – empathetic
Creative - need to see the big picture
Thinking - want all the details
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
31
C
Consider
id H
Human Dynamics
D
i
„
Anticipate communication
barriers
„
„
„
Demographic or cultural factors
Defensiveness
Identify appropriate sites and
times for interviews
„
„
Privacy
Free from distractions
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
32
Strategies for Food Recall
„
„
„
„
„
„
Ask about food preferences
Rule in/out some foods
Show calendar to identify key days
and jog memory
R i
Review
receipts
i
and/or
d/ checkbook
h kb k
If buffet, clearly describe each food
Show the menu if available
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
33
Restaurants
„
„
Be as specific
p
as
possible
How many
“combination
chicken platters”
can there
th
b
be?
?
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
34
Challenges
g Duringg Interview
„
Information often missed
„
„
„
„
Identify facility locations, extent of exposure,
timeline and specific signs and symptoms
Check for food or clinical samples
p
Consider non-foodborne transmission
Commercial food products
„
Obtain specific dates, locations, lot number and
product descriptions
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
35
Read Labels
Be Specific
„
Hamburger
„
Ground chuck
„
Ground sirloin
„
23% fat content
„
30% fat content
„
Lettuce
„
„
„
Shredded
Chopped
Type- iceberg v
romaine
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
36
I f
Information
ti Oft
Often Missed
Mi d
Location of facility (be specific)
Chain X store in Anytown, AL
„ Chain X store on corner of Main and
Fourth in Anytown, AL
„ Chain X store located at 245 Main
Street in Anytown, AL
„
Anytown
X
Main
Fou
urth
„
245 Main St
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
37
Information
I f
ti Oft
Often Missed
Mi d (cont.)
(
t)
„
Extent of exposure
„
„
„
„
Who else ate the food
Names and contact information of other
persons at event
How much did they eat?
Timeline information
„
„
„
Purchase date/time
Consumption date/time
Symptom onset date/time
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
38
Information
I f
ti Oft
Often Missed
Mi d (cont.)
(
t)
„
Specific signs and symptoms
„
Especially important if no laboratory confirmation
„
Check if food or clinical samples still
available
„
Information needed to assess potential
for non-foodborne routes of
transmission
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
39
Communication Barriers (cont.)
(cont )
„
Last meal bias
„
„
Irate consumer
„
„
Take multi-day food history
Be sensitive, adjust communication style
Cultural Diversity
„
Different cultures have different styles of
communicating
g ((age,
g ,g
gender,, cultural,,
ethnic)
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
40
The Last Meal Bias
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
41
Non-Foodborne Routes
Nonof Disease Transmission
„
„
„
„
Petting Zoos
Day Care Centers
Drinking Water
S i
Swimming
i P
Pools
l
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
42
Before Ending Interview
„
„
„
„
Ask about “Other Food”
A k questions
Ask
ti
as written
itt
Review for completeness and
accuracy
Ask if individuals have
„
„
„
Unanswered questions
Additional information
Thank them
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
43
Three
Th
Ph
Phases off IInterviewing
t i i g
1. Before
2. During
3. After
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
44
After the Interview
„
„
„
„
„
„
Keep track of interviewees and
interviewers
Fax questionnaires to Communicable
Di
Disease
(CD)
(CD), 334
334-206-3734
206 3734
Confirm all information was received
When notified and by whom
Number of possible attendees/patrons
Coordinate reports from others
involved (Area/Local staff)
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
45
“II can give you a six
six-word
word
formula for success. “Think
things through
thro gh – then follo
follow
through”
g
-Sir Walter Scott
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
46
Module Learning Objectives
„
„
„
„
List steps needed to prepare for an
investigation
Define foodborne outbreak (FBO)
Gather information to determine the
source
Identify means for searching for
additional
ddi i
l cases
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services
47
Group Exercise
Fraternity/Sorority Student Interview
Epidemiology Division
Bureau of Clinical Laboratories
Bureau of Environmental Services