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2004 Public Health Training and
Information Network (PHTIN) Series
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Site Sign-in Sheet
Please mail or fax your site’s sign-in sheet to:
Linda WhiteNC Office of Public Health Preparedness and ResponseCooper Building1902 Mail Service CenterRaleigh, NC 27699
FAX: (919) 715 - 2246
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Outbreak Investigation Methods
From Mystery to Mastery
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2004 PHTIN Training Development Team
Jennifer Horney, MPH - Director, Training and Education, NCCPHP
Pia MacDonald, PhD, MPH - Director, NCCPHP
Amy Nelson, PhD
Penny Padgett, PhD, MPH
Sarah Pfau, MPH
Amy Sayle, PhD, MPH
Michelle Torok, MPH, Doctoral Candidate
Drew Voetsch, MPH, Doctoral Candidate
Aaron Wendelboe, MSPH, Doctoral student
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Future PHTIN Sessions
August 17th. . . . . . . . . .“Interviewing Techniques”
September 14th. . . . . . .“Designing Questionnaires”
October 12th. . . . . . . . . “Analyzing Data”
December 14th. . . . . . . “Risk Communication”
Each session will be on a Tuesday from 10:00 am - 12:00 pm
(with time for discussion)
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Session I – VI Slides
After the airing of each session, NCCPHP will post PHTIN Outbreak Investigation Methods series slides on the following two web sites:
NCCPHP Training web site:http://www.sph.unc.edu/nccphp/training/index.html
North Carolina Division of Public Health, Office of Public Health Preparedness and Response
http://www.epi.state.nc.us/epi/phpr/
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Session II
“Study Design”
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Today’s PresentersMichelle Torok, MPHGraduate Research Assistant and Doctoral Candidate, NCCPHP
Amy Sayle, PhD, MPHMellon Writing Fellow, Duke University
Mary CrabtreeWorkplace Safety Manager, Department of Environment, Health,
and Safety, UNC Chapel Hill
Sarah Pfau, MPHModerator
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“Study Design” Learning Objectives
Upon completion of this session, you will:
• Understand what an analytic study contributes to an epidemiological outbreak investigation
• Understand the differences in methodology between cohort and case-control study designs
• Understand how to select cases and controls in a case-control study design
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“Study Design” Learning Objectives (cont’d.)
• Be able to describe the advantages and disadvantages of alternative forms of questionnaire administration in an outbreak investigation
• Know how to interpret odds ratios from case-control study data and risk ratios from cohort study data
• Be able to describe short- and long-term control measures that might be implemented in a food borne illness outbreak investigation
• Understand how to implement long-term control measures such as policy change at an institutional or community level
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Session I Review
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Session I Review
• Detected an outbreak of gastroenteritis at a university in
Texas, based on a March 11 complaint from a student
• Conducted:
– active case finding
– chart reviews
– hypothesis generating interviews
• 75 cases detected by March 12
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Session I Review (cont’d.)
• Collected stool specimens
– All negative for bacterial pathogens
– Assume viral pathogen
• Earliest date of exposure was March 5
• Conducted interviews with 7 of the earliest cases
(all students)
– Only commonality was 6 of 7 reported eating at deli
bar of main campus cafeteria
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Session I Review (cont’d.)
• Developed a leading hypothesis with the main
campus cafeteria as the suspect
– No source food identified
• Interviewed 30 of 31 cafeteria staff members
– Staff member who declined interview worked at deli
bar*
* Today’s session includes a follow up investigation with this staff
member
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Session I Review (cont’d.)
• Closed deli bar on March 12th based on:
– Link between 6 out of 7 interviewed cases
and a common food source
– Several unsanitary food handling practices
identified via an environmental health
investigation
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Basic Steps of an Outbreak Investigation
1. Verify the diagnosis and confirm the outbreak
2. Define a case and conduct case finding
3. Tabulate and orient data: time, place, person
4. Take immediate control measures
5. Formulate and test hypothesis
6. Plan and execute additional studies
7. Implement and evaluate control measures
8. Communicate findings
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Next Step: Analytic Study
• Test current hypothesis:“Main campus cafeteria / deli bar is source of infection”
• What do we know?
• What do we suspect?
• What can we “prove”?
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What do we know?
• We know…
– 75 cases reported by March 12 – all were students
who lived on campus
– All of cases sampled (n=7) reported eating at the
main campus cafeteria
• 6 of 7 at the deli bar
– No illness among off-campus students, faculty, or
community members
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What do we suspect?
• We suspect the main cafeteria is the source of
infection
• We also suspect the deli bar, in particular, may
be the outbreak source
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What can we “prove”?
• Can we “prove” it?
– Need to conduct an analytic study
– Need a testable hypothesis
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What hypothesis will be tested?
• Main cafeteria vs. other dining halls?
• Within the main cafeteria:
– Deli bar vs. grill?
– Salad bar vs. hot entrée?
• Food item vs. food handler at deli bar?
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Our Hypothesis
A viral infection spread by food(s) or beverage(s) served at the university’s main cafeteria between March 5 and 10
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Source Population
Students (12,000)
2400 on campus
2000 meal plan
Town residents (39,000)
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Which Study Design?
• Cohort or case-control?
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Cohort Study
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Definition of a Cohort
In Epidemiology, “Any designated group of
individuals who are followed or traced over
a period of time.”
- Last, JM. A Dictionary of Epidemiology, 3rd ed. New York: Oxford University Press, 1995
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Cohort Study Types
A cohort study analyzes an exposure / disease relationship within the entire cohort.
• Prospective– The Framingham Study
• Retrospective – Usually used in outbreak investigations
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Cohort Study Design
Exposed Not Exposed
Develop Do Not Develop Do NotDisease Develop Disease Develop Disease Disease
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Cohort Study
Steps in a Cohort Study:
1. Identify Cohort
2. Administer Questionnaire
3. Analyze Data
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Cohort Study
Step 1 – Identify cohort
– Entire student body (n=12,000)
– On-campus students (n=2400)
– On campus students with meal plan who mainly ate at cafeteria
(n=2000)
– Sick students (n=75)
Do not select cohort so that either everyone is exposed
or everyone is diseased
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Cohort Study
Step 2 – Administer questionnaire– Step 2a – Determine exposure status
• Main cafeteria• Deli bar• Food item
– Step 2b – Determine disease status• Importance of well-defined case definition
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Cohort Study Example
Dartmouth University: 698 (13.8%) of 5060 students had conjunctivitis in spring 2002
• To identify risk factors... – web-based questionnaire set up
– E-mail sent to 3682 undergraduates
– No data entry-rapid analysis
• 1832 (50%) responded
An outbreak of conjunctivitis due to atypical Streptococcuspneumoniae. N Engl J Med. 2003;348 (12):1112-21.
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Cohort Study
Step 3 – Analyze data
Ill Not Ill Total
Exposed A B A+B
Unexposed C D C+D
Risk Ratio [A/(A+B)]
[C/(C+D)]
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Interpreting a Risk RatioThe risk ratio is the ratio of the risk of disease in exposed individuals to the risk of disease in unexposed individuals
• RR=1.0 = no association between exposure and disease
• RR>1.0 = positive association
• RR<1.0 = negative association
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Interpreting a Risk RatioExample: Outbreak of conjunctivitis at Dartmouth College
• RR = 2.5• Disease = Conjunctivitis• Exposure = Attended a fraternity / sorority party
“Students who attended a fraternity or sorority party had 2.5 times the risk of having conjunctivitis compared to students who did not attend a fraternity or sorority party”
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Cohort Study
• Preferred study design when:
– Members of cohort are easily identifiable
– Members of a cohort are easily accessible
– Exposure is rare
– There may be multiple diseases involved
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Cohort Study Example
• Recent norovirus outbreaks on cruise ships
• Attempt to interview all passengers
• Collect food history information
MMWR: December 13, 2002 / 51(49);1112-1115
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Cohort Study Examples• Shigellosis among swimmers in a Georgia park
– Used park registry to identify park visitors
Iwamoto M, Hlady G, Jeter M et al. Shigellosis among Swimmers in a Freshwater Lake-Georgia, 2003. Presented at the 53rd Annual Epidemic Intelligence Service Conference. Atlanta, GA. April, 2004.
• Whirlpools and Methicillin-Resistant Staphylococcus aureus– Occurred on a college football team
Begier EM, Barrett FK, Mshar PA et al. Body Shaving, Whirlpools, and Football: An Out break of Methicillin-Resistant Staphylococcus aureus Cutaneous Infections in a College Football Team-Connecticut, 2003. Presented at the 53rd Annual Epidemic Intelligence Service Conference. Atlanta, GA. April, 2004.
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Question & Answer Opportunity
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Case Control Study
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Case-Control Study Design
Exposed Not Exposed Exposed Not Exposed
Disease No Disease
“CASES” “CONTROLS”
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Cohort versus Case-Control Study
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Case-Control Study
Steps in a Case-Control Study:
1. Identify the source population2. Establish a case definition and select cases3. Select controls4. Analyze data
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Case-Control Study
Step 1 - Identify source population
• Represents the population that gives rise to the cases; is similar to a cohort study
• In the Texas case study, the source population is: all students who live on-campus
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Case-Control Study
Step 2 – Establish a case definition and select cases
• A standard set of criteria for deciding disease status– Clinical criteria, time, place, and
person
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Case Study Case Definition
Study HypothesisA viral infection spread by food(s) or beverage(s) served at the university’s main cafeteria between March 5 and 10
Case definition• Vomiting or diarrhea (≥3
loose bowel movements during a 24-hour period)
• Onset on or after March 5, 1998
• On-campus student seen at an emergency room or the Student Health Center
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Case-Control Study
Step 3 – Select Controls
• Represent source population
– On-campus students in Texas case study
• Collect same exposure information as for
cases
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Case-Control Study
Step 3 – Select Controls (cont’d.)
• Sources of controls
– Random sample
– Friends
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Case-Control Study
Cases Controls
Exposed A B
Unexposed C D
Odds Ratio (A/C)/(B/D)=(A*D)/(B*C)
Step 4 – Analyze Data
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Interpreting an OR
The odds ratio is interpreted in the same way as a risk ratio:
• OR=1.0 = no association between exposure and disease
• OR>1.0 = positive association
• OR<1.0 = negative association
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Interpreting an ORExample: Hepatitis A outbreak investigation• OR = 12.0• Disease = Hepatitis A• Exposure = Eating at restaurant X in April 2003
“Among those with Hepatitis A, the odds of having eaten at restaurant X in April, 2003 is 12 times greater among the cases than among the controls.”
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Case-Control Study
• Preferred study design when:
– Identifying or accessing the entire cohort would be cost prohibitive or too time consuming
– Disease of interest is rare– There are multiple exposures
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Cohort versus Case-Control
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Cohort versus Case-Control
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Question & Answer Opportunity
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Activity 1 Choose a study design to
investigate the source of the Texas outbreak
Completion time: 5 minutes
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Activity 1Will you conduct a cohort study or a case-
control study? List 2 reasons for your choice.
Recall the TX Case Study scenario:
• Source population = 2,400 on-campus students
• 75 cases of illness reported by March 12
• Hypothesis: Viral infection spread by food(s) or
beverage(s) served at the university’s main cafeteria
between March 5 and 10
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Activity 1 Answer
The TX investigators decided to conduct a
case-control study.
• The disease is rare (only 3% are cases)
• Interested in a single disease
• Exposure of interest (eating in main
cafeteria) is common
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Matching in Case-Control Studies
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Matching in Case-Control Studies
• Makes one or more case and control attributes similar (e.g., age, gender, residence)
• An unmatched study design is usually preferred
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Matching: Points to Consider
• More complex data analysis required
• Inability to assess role of matching factor on disease status– Do not match on exposure factor
• Potential for over-matching
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Texas Dept. of HealthStudy Design
• Matched case-control study conducted among students at the university
CASES CONTROLS
Ill students who could be reached in the dorm room
Roommates who had not become ill
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Hypothesis Testing Results
Texas case study:– Eating at the main cafeteria was not
associated with illness– Eating lunch at the deli bar on March 9 or
March 10 appeared to be associated with illness
• Individual food items could not be evaluated• Conduct a larger, unmatched case-control study to
identify high risk items or practices at deli bar
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Hypothesis Testing:Validity of Results
• Selection / participation bias
– Only 29 of 75 cases interviewed
• Not enough information on deli bar
• Matching on a risk factor
– Can’t evaluate person-to-person transmission
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5 Minute Break
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Refine Hypothesis:Update TX Case Definition
• On-campus student with vomiting or diarrhea (≥3
loose bowel movements during a 24-hour
period)
• Onset of disease on or after March 5, 1998
• Member of the university meal plan
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Test the Refined Hypothesis:Case-Control Study
• 40 cases were randomly selected from those reported to TDH by a local emergency room or the Student Health Center
• 160 controls who did not have nausea, vomiting, or diarrhea since March 5 were randomly selected from the university meal plan list
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Questionnaire Administration
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Questionnaire Administration Options
1. Interviewer administeredA. Face to face interviewB. Telephone interview
2. Self-administeredA. Mail-outB. EmailC. Web-based
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Face-to-Face Interview
• Pros– Higher response rate– Can have more complex skip patterns– More accurate recording of responses
• Cons– Costly– Potential for interviewer bias– Less anonymous than self-administered– Participants less inclined to be honest
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Telephone Interview
• Pros– Similar advantages as face-to-face, but less
costly– Quicker access to participants
• Cons– Similar disadvantages as face-to-face– Unable to capture important visual information
(e.g. Rash, working conditions)
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Self-administered Questionnaire
• Pros– More anonymous – May collect more honest responses– Data collection takes less personnel time– Less expensive
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Self-administered Questionnaire
• Cons– Questionnaire must be simple– Lower response rate– Waiting time to collect completed
questionnaires– Potentially more errors in recording responses
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Activity 2 Choose a method of
questionnaire administration for the TX Case Study
Completion time: 5 minutes
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Activity 2Special Considerations
When choosing a method of questionnaire administration, keep in mind that:
1. You plan to contact 40 cases and 160 controls
2. Spring break is March 13-23. Today is March 13.
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Questionnaire Administration Options
Choose a method below for the TX case study. List 2 reasons for your choice.
1. Interviewer-administeredA. Face-to-face interviewB. Telephone interview
2. Self-administeredA. Mail-outB. EmailC. Web-based
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Activity 2 Answer
The TX investigators decided to administer the
questionnaire by telephone.
• Need for fast responses; subjects likely to be out
of town
• Desire for accurate information, high response
• Anonymity not likely to be an issue
• Take measures to avoid interviewer bias
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Test the Refined Hypothesis:Conduct Case-Control Study
• Texas study questionnaire administered
by telephone March 15 - 23
– Called students at dormitory room or their
home telephone number as recorded in
university records
– Follow-up phone calls were made to students,
when possible or necessary
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Test the Refined Hypothesis:Carry out Case-Control
• 36 cases and 144 controls were enrolled
• Cases included in the study were similar to
all cases with respect to gender, age, year
in college, and date of onset
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Test the Refined Hypothesis:Case-Control Results
Exposure Odds Ratio
Salad Bar Lunch, Mar 9 0.8
Salad Bar Dinner, Mar 9 1.1
Deli Bar Lunch, Mar 9 11.1
Deli Bar Dinner, Mar 9 7.1
Deli Bar Lunch, Mar 10 5.7
28 (78%) of the 36 cases reported eating at the deli bar during at
least one of the implicated meals.
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Test the Refined Hypothesis:Case-Control Results*
Exposure Odds RatioAmerican Cheese 3.40
Swiss Cheese 0.61
Ham 1.50
Turkey 0.95
Mayonnaise 3.10
*Only participants reporting eating at deli bar during Mar 9-10 included
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Interpretation of Analysis Results
• What do we know?
• What do we suspect?
• What can we “prove”?
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What do we know?
• We know that 125 cases of vomiting or diarrhea have been reported – all students
• We know the cases were more likely to have eaten at the deli bar Mar 9 – Mar 10
• We know the pathogen is not bacterial
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What do we suspect?
• We suspect that cases were more likely to have eaten ham, mayonnaise, and American cheese, but results were not statistically significant
• We suspect the pathogen is viral
• We suspect the food was contaminated by cafeteria staff
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What can we “prove”?
• We have “proven” the source came from the deli bar
• We will probably never “prove” which food was the source
• We may yet “prove” the pathogen is viral
• We may yet “prove” the food was contaminated by cafeteria staff
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Interpretation of Analysis Results
What questions do we still have?
– Lab results for viral pathogen
– Missing food handler who worked at deli bar
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Texas Case Study:Additional Investigations
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Additional Investigations:Environmental Sampling Results
• Water and ice samples obtained from the cafeteria on March 12 were negative for fecal coliforms
• Stool cultures and rectal swabs from the 23 food handlers were negative for bacteria
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Additional Investigations:The Missing Food Handler
• The staff member who initially refused to be interviewed worked primarily at the deli bar
• She finally agreed to be interviewed on March 23, and reported slicing ham on March 9 for use at the deli bar during lunch and dinner that day and lunch on March 10– Prepared and served sandwiches for March 9 and 10
meals– Wore gloves while slicing ham and while serving at
the deli bar
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Additional Investigations:The Missing Food Handler
• Denied any gastrointestinal illness during the outbreak period
• Reported her infant had been sick with watery diarrhea since March 7
• Had not thought that hand washing was an important activity because she wore gloves during food preparation and serving
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Additional Investigations:Viral Testing
• Of 18 fresh stool specimens sent to CDC, 9 (50%) had evidence of Norwalk-like virus (NLV) by reverse transcriptase polymerase chain reaction (RT-PCR)
• Of the four deli foods available from the implicated meals, only the March 9 ham sample was positive for the NLV RNA
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Additional Investigations:Viral Testing
• NLV was also detected by RT-PCR in a stool sample from the ill infant of the food handler who prepared the deli sandwiches on March 9
• The sequence of the amplified product was identical to those PCR products from the ill students and the deli ham
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Texas Case Study Conclusions
• The evidence implicates the food handler as the source of the outbreak
• Diarrheal illness in the food handler’s child preceded the outbreak
• Food handler prepared ingredients and sandwiches served at the deli bar during the time that her child was ill
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Texas Case Study Conclusions
• NLV was isolated from the child’s stool and was identical to that obtained from ill students and the deli ham
• The food handler was not necessarily ill or infected– May have transferred contamination directly
from her ill infant
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Control Measures
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Control Measures
• At this point in the investigation, you should consider short-term interventions for the control of the current outbreak.
• Long-term interventions which might prevent the spread of foodborne diseases at the cafeteria in the future should be considered and implemented after the situation is under control.
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Activity 3: Identify potential control measures
Completion time: 5 minutes
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Activity 3
Part A: Please write down 2 suggested short-term control measures for the TX outbreak
Part B:Please write down 2 suggested long-term control measures for the TX outbreak
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Possible Short-Term Control Measures
• Throw away all leftover deli bar foods and
ingredients
• Clean and disinfect all equipment and surfaces in
the deli bar
• Require all food handlers to submit a stool
specimen before allowing them to return to work?
• Quarantine or isolation a necessary consideration
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Possible Long-Term Control Measures
• Education on proper food handling procedures
including:
– hand washing
– hot-holding and cold-holding temperatures
• Develop a sick food handlers policy
• Consider institution’s responsibility to assure
recommended policies and practices are
followed
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Control Measures: Follow Up
The health department should monitor until a safe food handling system has been established
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Control Measures: Follow Up
A food safety specialist and / or sanitarian should return to the university cafeteria in one month and on a quarterly basis for at least the first year
– Make sure no further disease is occurring – Assess the development and implementation of
appropriate policies– Evaluate practice of good food handling procedures
by employees – Assure ongoing oversight by / within the institution
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Control Measures: Policy Change
Develop actions or policies for the campus food service to prevent a recurrence by consulting with:
– University administrators or their representatives
– Supervisors in the cafeteria – Food handlers– Union representatives (if applicable) – Staff from the local health department
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Control Measures
Today’s Guest Expert Lecturer:
Mary Crabtree
Workplace Safety Manager, Department of Environment, Health,
and Safety, UNC Chapel Hill
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UNC Norovirus Outbreak
ehs.unc.edu
962-5507
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Objectives
• General Information• UNC Norovirus Outbreak• Actions taken within UNC• Debriefing within UNC• Attendance at NCSU’s debriefing• Lessons Learned• Recommendations for Other
Institutionsehs.unc.edu
962-5507
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General Information
• In January, EHS implemented a Hand Washing Campaign with Orange County Health Dept.
• Goal: To reduce overall risk of exposure to infectious diseases and food borne illnesses
ehs.unc.edu
962-5507
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General Information
Carolina Dining Services:
• Two full dining facilities • Four snack facilities• Aramark: contractor
for food services• Serve 7,000 meals per
day in full dining halls
ehs.unc.edu
962-5507
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UNC Norovirus Outbreak
Cases Reported:• On January 21, 2004,
66 students reported to Student Health Services
• Symptoms: nausea, vomiting, diarrhea, acute gastroenteritis
ehs.unc.edu
962-5507
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UNC Norovirus Outbreak
ehs.unc.edu
962-5507
Data Sources:
UNC Chapel Hill Student Health Services (“SHS”);
UNC Chapel Hill Housing & Residential Education (“Not Seen”)
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UNC Norovirus Outbreak
• Overall, ~250 students became ill during this outbreak.
ehs.unc.edu
962-5507
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UNC Norovirus Outbreak
Orange County Health Department’s Finding (February 2, 2004):
• Outbreak from a single source• Time limited• Common environmental exposure• 5x more likely in one location of dining hall• 4x more likely if the student ate salad bar• No point to a specific salad item• No procedural problems found with the
Dining Servicesehs.unc.edu
962-5507
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Action Taken Within UNC
Student Health Services• Immediately notified Orange County
Health Dept.• Enacted Disaster Plan and notified
EHS• Assisted with Incident
Communications Plan• Posted “Student Illness Update” on
websitesehs.unc.edu
962-5507
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Action Taken within UNC
Environment, Health, and Safety• Established contact with entities that would be
involved (i.e. Hskpg, UEOHC, Athletics, Housing & Residential Education)
• Coordinated Incident Communications Plan• Prepared clean-up packets for Residential Halls• Met with Housekeeping Zone Managers
- Review Clean-up procedures
- Identification of areas which students exhibit illness
• Discussed clean-up procedures with Athletics (Men’s Basketball Game January 24)
ehs.unc.edu
962-5507
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Action Taken within UNC
ehs.unc.edu
962-5507
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Action Taken within UNC
Housing and Residential Education• Distributed EHS clean-up kits to
residential halls• Assisted with Incident
Communications Plan• Prepared & distributed illness survey
(for students who did not go to SHS for treatment)
ehs.unc.edu
962-5507
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Action Taken within UNC
Carolina Dining and Aramark:• Placed “Hand Wash” tents on
dining tables• Placed additional hand
washing stations throughout dining halls
• Reviewed staff absenteeism records
• Fully assisted health investigators
ehs.unc.edu
962-5507
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Debriefing within UNC
• Debriefing was conducted on March 2• Parties involved:
- Environment, Health & Safety- Student Health Services- Carolina Dining Services (including
Aramark)- Housing & Residential Education- Housekeeping Services
ehs.unc.edu
962-5507
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Debriefing within UNC• Reviewed OCHD Findings• Effectiveness of Communications• Involvement of Key Groups for
decision making• What if any other potential resources
were needed
- Further analysis by School of Public Health
• What other action can be taken to prevent / mitigate reoccurrence
ehs.unc.edu
962-5507
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Attendance at NCSU’s Debriefing
• Collaboration – What could we have done better?
• Paralleled UNC’s case• After 6th case at SHS,
implemented survey• Saw 410 students
from Feb. 9 – Mar. 4
ehs.unc.edu
962-5507
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Lessons Learned
• Initiate medical survey at the time of complaint (to complement the Health Department)
• Immediately review geographic data –who ate where and when
• Continue contingency planning with outside parties
• Implement a stronger Hand Washing Campaignehs.unc.edu
962-5507
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Recommendations for Other Institutions
• Establish emergency communication procedures
• Openly discuss contingency plans and responsibilities internally and with public health officials
• Conduct drills (i.e. table top) to identify needs• Review Contracts of food service and establish
a working partnership• Implement stronger health campaigns• Share Informationehs.unc.edu
962-5507
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Question & Answer Opportunity
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Session II Summary
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Session II Summary
• An analytic study is used to test scientific hypotheses that may help support actions for specific control measures and to help prevent recurrence of problem.
• Risk ratios and odds ratios are used to assess an association between the exposure and illness.
• Risk and risk ratios can be directly calculated from cohort studies, but this design usually demands more resources.
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Session II Summary
• Case-control studies, when conducted properly, are generally adequate and usually more efficient.
• A case definition with specific criteria helps you select your study population, as long as it does not include the hypothesis.
• Controls need to be representative of the source population, and not matched on the exposure factor if matching is used.
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Session II Summary
• Interviewer administered questionnaires are generally higher quality, but more costly and time consuming.
• Self-administered questionnaires are generally more convenient but lower quality.
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Session II Summary
• Short-term control measures help contain an outbreak.
• Long-term control measures help establish preventive measures and future spread of disease.
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Next Session August 17th10:00 a.m. - Noon
Topic: “Interviewing Techniques”
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Session II Slides
Following this program, please visit one of the web sites below to access and download a copy of today’s slides:
NCCPHP Training web site:http://www.sph.unc.edu/nccphp/training/index.html
North Carolina Division of Public Health, Office of Public Health Preparedness and Response
http://www.epi.state.nc.us/epi/phpr/
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Site Sign-in Sheet
Please mail or fax your site’s sign-in sheet to:
Linda WhiteNC Office of Public Health Preparedness and ResponseCooper Building1902 Mail Service CenterRaleigh, NC 27699
FAX: (919) 715 - 2246